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Organisms that cause pneumonia: Causes of Pneumonia | CDC

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What Causes Pneumonia? | American Lung Association

Pneumonia can be caused by a wide variety of bacteria, viruses and fungi in the air we breathe. Identifying the cause of your pneumonia can be an important step in getting the proper treatment.

Bacteria

The most common type of bacterial pneumonia is called pneumococcal pneumonia. Pneumococcal pneumonia is caused by the Streptococcus pneumoniae germ that normally lives in the upper respiratory tract. It infects over 900,000 Americans every year.

Bacterial pneumonia can occur on its own or develop after you’ve had a viral cold or the flu. Bacterial pneumonia often affects just one part, or lobe, of a lung. When this happens, the condition is called lobar pneumonia. Those at greatest risk for bacterial pneumonia include people recovering from surgery, people with respiratory disease or viral infection and people who have weakened immune systems.

Some types of bacteria cause what is known as “atypical” pneumonia, including:

  • Mycoplasma pneumoniae, a tiny wide-spread bacterium that usually infects people younger than 40 years old, especially those living and working in crowded conditions. The illness is often mild enough to go undetected and is sometimes referred to as walking pneumonia.
  • Chlamydophila pneumoniae, which commonly causes upper respiratory infections year-round, but can also result in a mild form of pneumonia.
  • Legionella pneumophila, which causes a dangerous form of pneumonia called Legionnaire’s disease. Unlike other bacterial pneumonias, Legionella is not passed from person to person. Outbreaks of the disease have been linked to exposure to contaminated water from cooling towers, whirlpool spas, and outdoor fountains.

These bacteria are referred to as “atypical” because pneumonia caused by these organisms might have slightly different symptoms, appear different on a chest X-ray, or respond to different antibiotics than the typical bacteria that cause pneumonia. Even though these infections are called “atypical,” they are not uncommon.

Viruses

Viruses that infect the upper respiratory tract may also cause pneumonia.  The influenza virus is the most common cause of viral pneumonia in adults. Respiratory syncytial virus (RSV)  is the most common cause of viral pneumonia in young children. Most viral pneumonias are not serious and last a shorter time than bacterial pneumonia.

Viral pneumonia caused by the influenza virus may be severe and sometimes fatal. The virus invades the lungs and multiplies; however, there are almost no physical signs of lung tissue becoming filled with fluid. This pneumonia is most serious in people who have pre-existing heart or lung disease and pregnant women. Read about the connection between the flu and pneumonia.

Viral pneumonias may be complicated by a secondary invasion of bacteria, with all the typical symptoms of bacterial pneumonia.

Fungi

Fungal pneumonia is most common in people with chronic health problems or weakened immune systems, and in people who are exposed to large doses of certain fungi from contaminated soil or bird droppings.

Pneumocystis pneumoniais a serious fungal infection caused by Pneumocystis jirovecii. It occurs in people who have weak immune systems due to HIV/AIDS or the long-term use of medicines that suppress their immune systems, such as those used to treat cancer or manage organ transplants.

The following are three fungi that occur in the soil in some parts of the United States and can cause some people to get pneumonia.

  • Coccidioidomycosis. This fungus is found in Southern California and the desert Southwest. It is the cause of valley fever.
  • Histoplasmosis. This fungus is found in the Ohio and Mississippi River Valleys.
  • Cryptococcus. This fungus is found throughout the United States in bird droppings and soil contaminated with bird droppings.

Learn About Pneumonia | American Lung Association

Pneumonia is a common lung infection caused by bacteria, a virus or fungi. It is often spread via coughing, sneezing, touching or even breathing, and those who don’t exhibit symptoms can also spread the illness.

What Is Pneumonia?

Pneumonia is an infection of the lungs that may be caused by bacteria, viruses, or fungi. The infection causes the lungs’ air sacs (alveoli) to become inflamed and fill up with fluid or pus. That can make it hard for the oxygen you breathe in to get into your bloodstream. The symptoms of pneumonia can range from mild to severe, and include cough, fever, chills, and trouble breathing.

Many factors affect how serious a case of pneumonia is, such as the type of germ causing the lung infection, the person’s age, and their overall health. The people most at risk are infants and young children, adults 65 or older, and people who have other health problems.

Pneumonia is a leading cause of hospitalization in both children and adults. Most cases can be treated successfully, although it can take weeks to fully recover. Tens of thousands of people in the U.S. die from pneumonia every year, most of them adults over the age of 65.

What Causes Pneumonia?

Pneumonia can be caused by a wide variety of bacteria, viruses and fungi in the air we breathe. Identifying the cause of your pneumonia can be an important step in getting the proper treatment.

Learn more about what causes pneumonia.

What Are the Risk Factors?

Anyone can get pneumonia, but many factors can increase your chances of getting sick and having a more severe illness. One of the most important factors is your age. People age 65 and over are at increased risk because their immune system is becoming less able to fight off infection as years go by. Infants and children two years of age or younger are also at increased risk because their immune systems are not yet fully developed.

Other risk factors can be grouped into three main categories: medical conditions, health behaviors, and environment.

Medical conditions

  • Chronic lung diseases such as COPD, bronchiectasis, or cystic fibrosis that make the lungs more vulnerable.
  • Other serious chronic illnesses, such as heart disease, diabetes and sickle cell disease.
  • A weakened immune system due to HIV/AIDs, an organ transplant, chemotherapy or long-term steroid use.
  • Difficulty swallowing, due to stroke, dementia, Parkinson’s disease, or other neurological conditions, which can result in aspiration of food, vomit or saliva into the lungs that then becomes infected.
  • Recent viral respiratory infection—a cold, laryngitis, influenza, etc.
  • Hospitalization, especially when in intensive care and using a ventilator to breathe.

Health behaviors

  • Cigarette smoking, which damages the lungs.
  • Drug and alcohol abuse, which increase the risk of aspiration pneumonia.

Environment

  • Exposure to certain chemicals, pollutants or toxic fumes, including secondhand smoke.

Pneumonia | Johns Hopkins Medicine

What is pneumonia?

Pneumonia is an infection of one or both of the lungs caused by bacteria, viruses, or fungi. It is a serious infection in which the air sacs fill with pus and other liquid.

What causes pneumonia?

There are more than 30 different causes of pneumonia, and they’re grouped by the cause. The main types of pneumonia are:

  • Bacterial pneumonia. This type is caused by various bacteria. The most common is Streptococcus pneumoniae. It usually occurs when the body is weakened in some way, such as by illness, poor nutrition, old age, or impaired immunity, and the bacteria are able to work their way into the lungs. Bacterial pneumonia can affect all ages, but you are at greater risk if you abuse alcohol, smoke cigarettes, are debilitated, have recently had surgery, have a respiratory disease or viral infection, or have a weakened immune system.

  • Viral pneumonia. This type is caused by various viruses, including the flu (influenza), and is responsible for about one-third of all pneumonia cases. You may be more likely to get bacterial pneumonia if you have viral pneumonia.

  • Mycoplasma pneumonia. This type has somewhat different symptoms and physical signs and is referred to as atypical pneumonia. It is caused by the bacterium Mycoplasma pneumoniae. It generally causes a mild, widespread pneumonia that affects all age groups.

  • Other pneumonias. There are other less common pneumonias that may be caused by other infections including fungi.

Who is at risk for pneumonia?

Anyone can get pneumonia. However, the following groups are at the highest risk:

What are the symptoms of pneumonia?

The symptoms of bacterial pneumonia include:

  • Bluish color to lips and fingernails

  • Confused mental state or delirium, especially in older people

  • Cough that produces green, yellow, or bloody mucus

  • Fever

  • Heavy sweating

  • Loss of appetite

  • Low energy and extreme tiredness

  • Rapid breathing

  • Rapid pulse

  • Shaking chills

  • Sharp or stabbing chest pain that’s worse with deep breathing or coughing

  • Shortness of breath that gets worse with activity

Early symptoms of viral pneumonia are the same as those of bacterial pneumonia, which may be followed by:

Mycoplasma pneumonia has somewhat different symptoms, which include a severe cough that may produce mucus.

How is pneumonia diagnosed?

Diagnosis is usually made based on your recent health history (such as surgery, a cold, or travel exposures) and the extent of the illness. Based on these factors, your healthcare provider may diagnose pneumonia simply on a thorough history and physical exam. The following tests may be used to confirm the diagnosis:

  • Chest X-ray. This test takes pictures of internal tissues, bones, and organs, including the lungs.

  • Blood tests. This test may be used to see whether infection is present and if infection has spread to the bloodstream (blood cultures). Arterial blood gas testing checks the amount of oxygen in your bloodstream.

  • Sputum culture. This test is done on the material that is coughed up from the lungs and into the mouth. It’s often used to see if there’s an infection in the lungs.

  • Pulse oximetry. An oximeter is a small machine that measures the amount of oxygen in the blood. A small sensor is taped or clipped onto a finger. When the machine is on, a small red light can be seen in the sensor. The test is painless and the red light does not get hot.

  • Chest CT scan. This imaging procedure uses a combination of X-rays and computer technology to produce sharp, detailed horizontal, or axial, images (often called slices) of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed than regular X-rays.

  • Bronchoscopy. This is direct exam of the bronchi (the main airways of the lungs) using a flexible tube (called a bronchoscope). It helps to evaluate and diagnose lung problems, assess blockages, and take out samples of tissue and/or fluid for testing,

  • Pleural fluid culture. In this test, a sample of a fluid sample is taken from the pleural space. This is the space between the lungs and chest wall. A long, thin needle is put through the skin between the ribs and into the pleural space. Fluid is pulled into a syringe attached to the needle. It is sent to the lab where it’s tested to find out which bacteria is causing the pneumonia.

How is pneumonia treated?

Treatment depends on the type of pneumonia you have. Most of the time, pneumonia is treated at home, but severe cases may be treated in the hospital. Antibiotics are used for bacterial pneumonia. Antibiotics may also speed recovery from mycoplasma pneumonia and some special cases. Most viral pneumonias don’t have specific treatment. They usually get better on their own.

Other treatment may include eating well, increasing fluid intake, getting rest, oxygen therapy, pain medicine, fever control, and maybe cough-relief medicine if cough is severe.

Can pneumonia be prevented?

Check with your healthcare provider about getting immunizations. The flu is a common cause of pneumonia. Because of that, getting a flu shot every year can help prevent both the flu and pneumonia.

There is also a pneumococcal vaccine. It will protect you from a common form of bacterial pneumonia. Children younger than age 5 and adults ages 65 and older should get this shot.

The pneumococcal shot is also recommended for all children and adults who are at increased risk of pneumococcal disease due to other health conditions.

What are the complications of pneumonia?

Most people with pneumonia respond well to treatment, but pneumonia can be very serious and even deadly.

You are more likely to have complications if you are an older adult, a very young child, have a weakened immune system, or have a serious medical problem like diabetes or cirrhosis. Complications may include:

  • Acute respiratory distress syndrome (ARDS). This is a severe form of respiratory failure.

  • Lung abscesses. These are pockets of pus that form inside or around the lung. They may need to be drained with surgery

  • Respiratory failure. This requires the use of a breathing machine or ventilator.

  • Sepsis. This is when the infection gets into the blood. It may lead to organ failure.

Key points about pneumonia

  • Pneumonia is an infection of one or both of the lungs caused by bacteria, viruses, or fungi.

  • There are more than 30 different causes of pneumonia, and they’re grouped by the cause. The main types of pneumonia are bacterial, viral, and mycoplasma pneumonia.

  • A cough that produces green, yellow, or bloody mucus is the most common symptom of pneumonia. Other symptoms include fever, shaking chills, shortness of breath, low energy, and extreme tiredness.

  • Pneumonia can often be diagnosed with a thorough history and physical exam. Tests used to look at the lungs, blood tests, and tests done on the sputum you cough up may also be used.

  • Treatment depends on the type of pneumonia you have. Antibiotics are used for bacterial pneumonia. It may also speed recovery from mycoplasma pneumonia and some special cases. Most viral pneumonias don’t have a specific treatment and just get better on their own. Other treatment may include a healthy diet, more fluids, rest, oxygen therapy, and medicine for pain, cough, and fever control.

  • Most people with pneumonia respond well to treatment, but pneumonia can cause serious lung and infection problems. It can even be deadly.

Which gram-positive bacteria can cause bacterial pneumonia?

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  • Pneumonia

    Pneumonia is a form of acute respiratory infection that affects the lungs. The lungs are made up of small sacs called alveoli, which fill with air when a healthy person breathes. When an individual has pneumonia, the alveoli are filled with pus and fluid, which makes breathing painful and limits oxygen intake.

    Pneumonia is the single largest infectious cause of death in children worldwide. Pneumonia killed 808 694 children under the age of 5 in 2017, accounting for 15% of all deaths of children under five years old. Pneumonia affects children and families everywhere, but is most prevalent in South Asia and sub-Saharan Africa. Children can be protected from pneumonia, it can be prevented with simple interventions, and treated with low-cost, low-tech medication and care.

    Causes

    Pneumonia is caused by a number of infectious agents, including viruses, bacteria and fungi. The most common are:

    • Streptococcus pneumoniae – the most common cause of bacterial pneumonia in children;
    • Haemophilus influenzae type b (Hib) – the second most common cause of bacterial pneumonia;
    • respiratory syncytial virus is the most common viral cause of pneumonia;
    • in infants infected with HIV, Pneumocystis jiroveci is one of the most common causes of pneumonia, responsible for at least one quarter of all pneumonia deaths in HIV-infected infants.

    Transmission

    Pneumonia can be spread in a number of ways. The viruses and bacteria that are commonly found in a child’s nose or throat, can infect the lungs if they are inhaled. They may also spread via air-borne droplets from a cough or sneeze. In addition, pneumonia may spread through blood, especially during and shortly after birth. More research needs to be done on the different pathogens causing pneumonia and the ways they are transmitted, as this is of critical importance for treatment and prevention.

    Presenting features

    The presenting features of viral and bacterial pneumonia are similar. However, the symptoms of viral pneumonia may be more numerous than the symptoms of bacterial pneumonia. In children under 5 years of age, who have cough and/or difficult breathing, with or without fever, pneumonia is diagnosed by the presence of either fast breathing or lower chest wall indrawing where their chest moves in or retracts during inhalation (in a healthy person, the chest expands during inhalation). Wheezing is more common in viral infections.

    Very severely ill infants may be unable to feed or drink and may also experience unconsciousness, hypothermia and convulsions.

    Risk factors

    While most healthy children can fight the infection with their natural defences, children whose immune systems are compromised are at higher risk of developing pneumonia. A child’s immune system may be weakened by malnutrition or undernourishment, especially in infants who are not exclusively breastfed.

    Pre-existing illnesses, such as symptomatic HIV infections and measles, also increase a child’s risk of contracting pneumonia.

    The following environmental factors also increase a child’s susceptibility to pneumonia:

    • indoor air pollution caused by cooking and heating with biomass fuels (such as wood or dung)
    • living in crowded homes
    • parental smoking.

    Treatment

    Pneumonia should be treated with antibiotics. The antibiotic of choice is amoxicillin dispersible tablets. Most cases of pneumonia require oral antibiotics, which are often prescribed at a health centre. These cases can also be diagnosed and treated with inexpensive oral antibiotics at the community level by trained community health workers. Hospitalization is recommended only for severe cases of pneumonia.

    Prevention

    Preventing pneumonia in children is an essential component of a strategy to reduce child mortality. Immunization against Hib, pneumococcus, measles and whooping cough (pertussis) is the most effective way to prevent pneumonia.

    Adequate nutrition is key to improving children’s natural defences, starting with exclusive breastfeeding for the first 6 months of life. In addition to being effective in preventing pneumonia, it also helps to reduce the length of the illness if a child does become ill.

    Addressing environmental factors such as indoor air pollution (by providing affordable clean indoor stoves, for example) and encouraging good hygiene in crowded homes also reduces the number of children who fall ill with pneumonia.

    In children infected with HIV, the antibiotic cotrimoxazole is given daily to decrease the risk of contracting pneumonia.

    Economic costs

    The cost of antibiotic treatment for all children with pneumonia in 66 of the countdown to 2015 countries for maternal, newborn and child survival is estimated at around US$ 109 million per year. The price includes the antibiotics and diagnostics for pneumonia management.

    WHO response

    The WHO and UNICEF integrated Global action plan for pneumonia and diarrhoea (GAPPD) aims to accelerate pneumonia control with a combination of interventions to protect, prevent, and treat pneumonia in children with actions to:

    • protect children from pneumonia including promoting exclusive breastfeeding and adequate complementary feeding;
    • prevent pneumonia with vaccinations, hand washing with soap, reducing household air pollution, HIV prevention and cotrimoxazole prophylaxis for HIV-infected and exposed children;
    • treat pneumonia focusing on making sure that every sick child has access to the right kind of care — either from a community-based health worker, or in a health facility if the disease is severe — and can get the antibiotics and oxygen they need to get well;

    A number of countries including Bangladesh, India, Kenya, Uganda and Zambia have developed district, state and national plans to intensify actions for the control of pneumonia and diarrhoea. Many more have integrated diarrhoea and pneumonia specific action into their national child health and child survival strategies. For many countries the post Millenium Development Goal agenda has explicitly included ending preventable diarrhoea and pneumonia deaths as a priority action.

    Bacterial Pneumonia: Symptoms, Causes, Treatment, Prevention

    Bacterial pneumonia is an infection of your lungs caused by certain bacteria. The most common one is Streptococcus (pneumococcus), but other bacteria can cause it too. If you’re young and basically healthy, these bacteria can live in your throat without causing any trouble. But if your body’s defenses (immune system) become weak for some reason, the bacteria can go down into your lungs. When this happens, the air sacs in your lungs get infected and inflamed. They fill up with fluid, and that causes pneumonia.

    You have a higher risk of getting bacteria pneumonia if you:

    • Are 65 or older
    • Have other conditions like asthma, diabetes, or heart disease
    • Are recovering from surgery
    • Don’t eat right or get enough vitamins and minerals
    • Have another condition that weakens your body’s defenses
    • Smoke
    • Drink too much alcohol
    • Have viral pneumonia

    People who have a weakened immune system also have an increased risk for bacterial pneumonia. These include those who recently had an organ transplant. People who are HIV positive, or who have leukemia, lymphoma, or severe kidney disease also stand a greater chance of developing the infection.

    Symptoms

    The symptoms can come on fast and furious, or they can creep up on you over a few days. Common symptoms are:

    • High fever up to 105 F
    • Coughing out greenish, yellow, or bloody mucus
    • Chills that make you shake
    • Feeling like you can’t catch your breath, especially when you move around a lot
    • Feeling very tired
    • Low appetite
    • Sharp or stabby chest pain, especially when you cough or take a deep breath
    • Sweating a lot
    • Fast breathing and heartbeat
    • Lips and fingernails turning blue
    • Confusion, especially if you’re older

    Prevention

    There are two kinds of shots for bacterial pneumonia:

    PCV13 (Prevnar 13) is for:

    • People 65 or older
    • Kids under 5 years
    • People who have a high risk of bacterial pneumonia

    PPSV23 (Pneumovax) is for:

    • People 65 or older
    • Children older than 2 who have a high risk of bacterial pneumonia
    • People between 19 and 64 who smoke or have asthma

    Talk to your doctor to find out if you or your child should get a shot.

    Besides getting shots, you can lower your risk of getting bacterial pneumonia by doing these things:

    Diagnosis

    Your doctor might be able to tell if you have bacterial pneumonia just by examining you and asking questions about your symptoms and general health. They’ll probably listen to your lungs with a stethoscope. That will allow them to hear sounds that show there’s fluid in your lungs. But if they are not sure, you might have to get a chest X-ray.

    Some people may need extra tests. These might include:

    • Pulse oximetry (a small gizmo clipped to your finger that checks for enough oxygen in your blood)
    • Blood tests
    • Tests of the gunk you cough up (“sputum”)
    • CT scan to look more closely at your lungs

    Treatment

    Your doctor probably will prescribe antibiotics. It’s very important that you finish all of these. Otherwise the bacteria may not all be killed and you could get sick all over again. Your doctor might also suggest medication for pain and fever.

    Other things you can do to help yourself get better:

    • Get lots of rest.
    • Drink plenty of fluids (they’ll loosen up the gunk in your lungs so you can cough it out).
    • Use a humidifier or take a warm bath (more gunk-loosening).
    • Don’t smoke.
    • Stay home until your fever goes down and you aren’t coughing anything out.
    Continued

    Most people who are treated for bacterial pneumonia start feeling better in a few days, but it can take a few weeks before you feel 100% better. Make sure you keep your follow-up appointments so your doctor can check your lungs.

    If the pneumonia is stubborn or severe, you might have to go to the hospital. If you go to the hospital you might get:

    • Oxygen treatment
    • IV fluids and medications
    • Treatments to help loosen up the gunk

    Community-Acquired Pneumonia in Adults | Cedars-Sinai

    Not what you’re looking for?

    What is community-acquired pneumonia?

    Pneumonia is a type of lung infection. It can cause breathing problems and other symptoms.
    In community-acquired pneumonia (CAP), you get infected in a community setting. It
    doesn’t happen in a hospital, nursing home, or other healthcare center.

    Your lungs are part of your
    respiratory system. This system supplies fresh oxygen to your blood and removes carbon
    dioxide, a waste product. When you breathe in air through your nose and mouth, it
    reaches the tiny air sacs of the lung (alveoli) through a series of tubes. From here,
    oxygen flows into your blood. Carbon dioxide flows out from the blood into the alveoli
    and you then breathe it out.

    Many germs can grow inside your
    body and cause disease. Specific types of germs can cause lung infection and pneumonia
    when they invade. This can cause your respiratory system to work poorly. For example,
    oxygen may not be able to get into your blood as easily. That can cause shortness
    of
    breath. If your body can’t get enough oxygen to survive, pneumonia may lead to
    death.

    Sometimes these germs can spread
    from person to person. When someone infected with one of these germs sneezes or coughs,
    you might breathe the germs into your lungs. If your immune system doesn’t kill the
    germs first, the germs might grow and cause pneumonia.

    CAP can result from infection with many types of germs. These include bacteria, viruses,
    fungi, or parasites. Symptoms from pneumonia can range from mild to severe. Certain
    types of germs are more likely to lead to serious infection.

    CAP is more common during the
    winter months, in older adults. But it can affect people of any age. It can be very
    serious especially in older adults, young children or people with other health
    problems.

    What causes community-acquired pneumonia?

    Many different types of germs can
    cause pneumonia. But certain types cause CAP more often. Worldwide, Streptococcus
    pneumoniae is a bacteria that is most often responsible for CAP in adults. Some other
    common bacteria that cause CAP are:

    • Haemophilus influenzae
    • Mycoplasma pneumoniae
    • Chlamydia pneumoniae
    • Legionella
    • Gram-negative bacilli
    • Staphylococcus aureus

    The flu (influenza) virus is the
    major viral cause of CAP. Having the flu also makes you more likely to get bacterial
    pneumonia. This type is often worse than viral pneumonia. Other types of viruses can
    also cause CAP, such as parainfluenza virus, echovirus, adenovirus, and coxsackievirus.
    In fact, viruses are likely responsible for most episodes of CAP. Fungi and parasites
    may also cause CAP.

    Who is at risk for community-acquired pneumonia?

    Certain things may raise your risk for CAP. Some of these are:

    • Smoking
    • Weak immune system, such as from drug
      treatment or a health problem like diabetes, cancer, or HIV
    • Other lung problems such as chronic obstructive pulmonary disease
    • Other health problems such as kidney failure
    • Use of certain medicines, including proton-pump inhibitors
    • Heavy alcohol use

    You also have a higher risk if you come into contact with other people who have pneumonia.

    What are the symptoms of community-acquired pneumonia?

    Symptoms of CAP often develop quickly. These symptoms may include:

    • Shortness of breath
    • Coughing
    • Heavy sputum
    • Fever and chills
    • Chest pain that is worse when you breathe or cough
    • Upper belly (abdomen) pain with
      nausea, vomiting, or diarrhea

    Your healthcare provider might
    notice other signs. These are a fast heartbeat, fast breathing rate, or certain sounds
    on a lung exam.

    How is community-acquired pneumonia diagnosed?

    Your healthcare provider will ask about your more recent symptoms and your past health
    problems. He or she will also do a physical exam, including a careful exam of your
    lungs.

    Lab tests can be very helpful in diagnosing CAP. Some tests you might need are:

    • Chest X-ray, which often confirms the diagnosis
    • Blood tests to check for infection and oxygen status of your blood
    • Blood culture tests to see if a germ is growing in your bloodstream
    • Tests of your sputum to see if a germ is present there

    How is community-acquired pneumonia treated?

    Your treatment may vary based on your symptoms and the type of germ causing the pneumonia.
    If you have severe pneumonia, you will likely need to stay in the hospital for some
    time. If you only have mild symptoms, you can probably get treatment at home.

    Antibiotics are a key treatment for
    bacterial CAP. Your healthcare provider will likely start you on this medicine even
    before identifying the type of bacteria (or other germ). The type of antibiotic can
    vary
    based on the germs known to be in your community, as well as your other health problems.
    Your healthcare provider will want to treat you with an antibiotic that is likely
    to
    kill whatever germ is causing your illness. But antibiotics don’t help in treating
    viral
    pneumonia and can often cause more harm than good.

    If you are getting treatment at
    home, you will probably take an antibiotic by mouth for 5 to 7 days. In most cases,
    you
    will start to feel better a few days after you start treatment.

    If you need to stay in the hospital, you will also need antibiotics specific to your
    case. In some cases, you may need to take these by IV (intravenously). Your healthcare
    provider might first start you on a certain antibiotic and then switch you to another
    one as your blood tests show what kind of germ is causing your infection. You may
    also need extra support, such as:

    • Extra oxygen
    • Fluids, if you are dehydrated
    • Breathing treatments
    • Respiratory support such as with a ventilator, for a severe case

    Most people start responding to treatment within a few days. A small portion of people
    who are treated in the hospital don’t respond to treatment within this time. If your
    symptoms don’t end, you may need a different antibiotic or treatment for complications
    from CAP.

    What are possible complications of community-acquired
    pneumonia?

    Lung abscess and, rarely, empyema are possible complications of CAP. In empyema, a
    collection of pus builds in the space between the lung and the chest wall. You usually
    need antibiotics and drainage to treat it. A CT scan can often help diagnose these
    problems.

    Respiratory failure and death are
    other possible complications. These are more likely to happen in older adults or those
    with other health problems.

    What can I do to prevent community-acquired pneumonia?

    You can lower your chances of
    getting CAP by having a yearly flu shot. The pneumococcal vaccines protect against
    S.
    pneumoniae and may help in preventing CAP. Healthcare providers advise this shot for
    all
    people older than 65. You may need it before this time if you have:

    • Chronic heart, lung, liver, or kidney
      disease
    • Diabetes
    • Alcoholism
    • HIV
    • Weak immune system

    Smokers and people living in
    long-term care facilities should also get this shot before age 65. There are
    two2vaccines against S. pneumoniae. Your healthcare provider may advise that you get
    both. You may need booster shots of the vaccine if you have your first pneumococcal
    vaccine before age 65 or if you have a weakened immune system.

    Practicing good hygiene can also
    help you lower your risk for CAP. That includes frequent handwashing.

    When should I call my healthcare provider?

    Get treatment right away if you
    have symptoms of pneumonia. If you are being treated for CAP as an outpatient, call
    your
    healthcare provider if your symptoms don’t improve in a few days after starting
    treatment, or they get worse.

    Key points about community-acquired pneumonia

    • Pneumonia is a type of lung infection. It can cause breathing problems and other symptoms.
      In CAP, infection occurs outside of a healthcare setting.
    • CAP is a leading cause of death in older adults. Most healthy young adults recover
      from CAP without a problem.
    • CAP can cause shortness of breath, fever, and cough.
    • You might need to stay in the hospital to be treated for CAP.
    • Most cases of CAP are caused by viruses and don’t require treatment with antibiotics.
    • Antibiotics are the key treatment for most types of CAP caused by bacteria.
    • Getting your vaccines as advised can
      help lower your risk for CAP.

    Next steps

    Tips to help you get the most from a visit to your healthcare provider:

    • Know the reason for your visit and what you want to happen.
    • Before your visit, write down questions you want answered.
    • Bring someone with you to help you ask questions and remember what your provider tells
      you.
    • At the visit, write down the name of a new diagnosis, and any new medicines, treatments,
      or tests. Also write down any new instructions your provider gives you.
    • Know why a new medicine or treatment is prescribed, and how it will help you. Also
      know what the side effects are.
    • Ask if your condition can be treated in other ways.
    • Know why a test or procedure is recommended and what the results could mean.
    • Know what to expect if you do not take the medicine or have the test or procedure.
    • If you have a follow-up appointment, write down the date, time, and purpose for that
      visit.
    • Know how you can contact your provider if you have questions.

    Not what you’re looking for?

    PNEUMONIA | Encyclopedia Around the World

    Contents of the article

    PNEUMONIA, pneumonia due to various causes, including infectious agents, chemical irritants and autoimmune reactions. Inflammation of the lungs can be accompanied by various infectious diseases, such as influenza, tuberculosis, histoplasmosis. Sometimes the term “pneumonia” is used more narrowly, in relation only to infectious pneumonia; inflammation caused by other factors is referred to in such cases as pneumonitis.

    Infectious pneumonia.

    The most common cause of pneumonia is a bacterial infection; the main pathogens include Streptococcus pneumoniae , Staphylococcus aureus , Klebsiella pneumoniae , Pseudomonas aeruginosa , Haemophylus influenzae and some species Legionella (causing severe pneumonia) Common pathogens are also special forms of bacteria that were not previously classified as bacteria, for example, mycoplasma, chlamydia and rickettsia.Mycobacterium tuberculosis ( Mycobacterium ), affecting mainly the lungs, can also cause pneumonia.

    Quite often, pneumonia is of a viral nature. It can be provoked by myxoviruses that cause influenza types A and B, as well as paramyxoviruses (parainfluenza viruses), adenoviruses and respiratory syncytial viruses.

    Another source of lung infections and pneumonia is microscopic fungi. Among the population living along the banks of the St.Lawrence, Mississippi and a number of other large rivers of North America, the fungus Histoplasma capsulatum is widespread, causing histoplasmosis ( see also MYCOSES).

    The cause of pneumonia is more and more opportunistic microorganisms, i.e. causing disease only when the immune system is weak. Thus, the unicellular fungus Pneumocystis carinii becomes the causative agent of pneumonia in infants and people with immunodeficiency. Immunodeficiency can occur with certain blood diseases, as a result of infection with HIV (human immunodeficiency virus), or as a result of anticancer chemotherapy.It is the development of Pneumocystis pneumonia that is the first manifestation of AIDS in most HIV-infected people.

    In persons with immunodeficiency, parasitic worms such as roundworms ( Ascaris lumbricoides ) and intestinal acne ( Strongyloides stercoralis ) sometimes enter the lungs.

    Pneumonia caused by chemicals.

    Inflammation of the lungs is the result of chemical irritation. For this effect, in particular, the use of chemical warfare agents, such as mustard gas, was calculated.Hundreds of chemical compounds, both natural and industrial, can cause pneumonia, including even nasal drops and liquid paraffin if they enter the lungs. Inflammation caused by exposure to chemicals develops either as a result of direct damage to lung tissue, or as a protective reaction of the body to these substances.

    Autoimmune pneumonia.

    In autoimmune diseases, such as systemic lupus erythematosus, the body produces antibodies against its own tissues; lung tissue exposure to these autoantibodies can lead to pneumonia.

    Development of pneumonia.

    Pathogenic microorganisms most often enter the lungs when infected droplets of saliva and mucus are inhaled, either from their own nose and mouth, or from other people who scatter droplets of saliva in the air when they cough, sneeze or talk. The human body has a number of defense mechanisms against infection. Due to the curvature and tortuosity of the upper airways, most droplets are usually trapped in them and do not penetrate into the lungs. The microbes still in the lungs are enveloped in a sticky secretion, and the synchronous vibrations of the smallest flexible cilia push them in the opposite direction (to the oral cavity).Other protective factors are antibodies produced by the immune system and white blood cells that kill microorganisms.

    Pneumonia occurs when microbes overcome the body’s defenses. In healthy people, this occurs in the case of a high virulence of the pathogen or its massive invasion (introduction). However, against the background of reduced resistance, even those microorganisms that rarely cause illness in people of good health can become the cause of extremely severe pneumonia (for example, Pneumocystis carinii ). When an infection enters the lungs, the body’s immune system is activated, and when it manages to suppress the growth of the pathogen, pneumonia ends.

    Symptoms.

    Symptoms and course of pneumonia depend on the type of pathogen and the activity of the body’s defense systems. The most common symptoms are fever, cough and shortness of breath. The cough is often accompanied by the secretion of phlegm – colorless, yellowish, greenish or even bloody, if lung tissue decays.Some microbes multiply extremely quickly, causing an acute course of the disease. Others (such as mycobacteria and fungi) grow much more slowly, causing chronic infection.

    Treatment.

    If it is established that a bacterial infection is the cause of pneumonia, then specific antimicrobial agents are used, primarily antibiotics. For viral infections, antibiotics are ineffective. Before the discovery and widespread use of antibiotics, pneumonia often led to the death of the patient.And now it is often fatal in the elderly or seriously ill people, as well as in those who suffer from impaired immune systems. Some strains of bacteria are so virulent that even physically fit people can die in less than a day after infection. Antibiotic treatment for bacterial infections usually lasts up to 2 weeks. Tuberculosis treatment requires 6-18 months. If there is a high risk of contracting pneumonia, vaccination is used to reduce the likelihood of developing a certain infection.

    The best way to deal with pneumonia caused by chemical irritants is to prevent further exposure to these substances. Autoimmune pneumonias are currently treated with agents that suppress the immune system (i.e., reduce its reactivity). However, this approach may increase susceptibility to infectious pneumonia.

    90,000 Don’t miss the first signs of pneumonia

    Pneumonia or pneumonia is a lung disease of predominantly infectious origin with damage to the end portions of the lungs – alveoli and impaired gas exchange at their level.The alveoli fill with fluid or purulent material, causing coughing up phlegm, less often hemoptysis, fever, chills, and shortness of breath. A variety of microorganisms can cause pneumonia, including bacteria, viruses, and fungi.

    Pneumonia can range from mild to life-threatening, and is most dangerous for infants and young children, people over 65, and people with weakened immune systems.

    Symptoms of pneumonia

    Signs and symptoms of pneumonia range from mild to severe, depending on factors such as the type of germ causing the infection, age, and general health.Mild signs and symptoms are often similar to those of a cold or flu, but they last longer.

    Signs and symptoms of pneumonia may include:

    • Chest pain when breathing or coughing
    • Cough with phlegm
    • Shortness of breath (shortness of breath) with less exertion, talking, at rest
    • Fatigue
    • Body temperature below normal (in adults over 65 years of age and people with a weak immune system)
    • Changes in mood, appetite, physical activity in the elderly (in combination with other factors)
    • Nausea, vomiting or diarrhea (in rare cases)

    Neonates and infants may show no signs of infection. There may be vomiting, fever and coughing, restlessness, fatigue and lack of energy, and trouble breathing and eating.

    When to see a doctor

    See your doctor if you have trouble breathing, chest pain, persistent fever (38.5 C) or higher, cough, especially if you cough up phlegm.

    It is important that people from risk groups see a doctor:

    • Adults over 65 years old
    • Children under 2 years of age with signs and symptoms
    • Patients with exogenous intoxication (alcohol, drugs)
    • People with poor and satisfactory health conditions or weakened immune systems
    • Patients with chronic diseases, especially in the stage of decompensation (obstructive bronchitis, heart failure, diabetes mellitus, liver cirrhosis)
    • People receiving chemotherapy or drugs that suppress the immune system
    • Long lying in bed

    For some older adults and people with heart failure or chronic lung disease, pneumonia can quickly become a life-threatening condition.

    Causes of pneumonia

    Many microorganisms can cause pneumonia. The most common are bacteria and viruses in the air we breathe, especially in indoor air. human immunity usually prevents these microorganisms from contracting the lungs. But sometimes these microbes can suppress the immune system, even if your health is generally good.

    Pneumonia is classified according to the types of microorganisms that cause it and the location of the infection.

    Community-acquired pneumonia

    Community-acquired pneumonia is the most common type of pneumonia. This happens outside of hospitals or other health care facilities. This could be caused by:

    Bacteria: The most common cause of bacterial pneumonia is pneumococcus (Streptococcus pneumoniae). This type of pneumonia can occur on its own or after you have a cold or flu. May affect one part (lobe) of the lung.

    Bacterial-like organisms. Mycoplasma pneumoniae can also cause pneumonia. It usually causes milder symptoms than other types of pneumonia. Walking pneumonia is the informal name for this type of pneumonia, which is usually not severe enough to warrant bed rest.

    Fungi or mold: This type of pneumonia is most common in people with chronic health problems or weakened immune systems, and in people who have inhaled large doses of organisms.The fungi that cause it can be found in soil or bird droppings and vary by geographic location.

    Viruses. Certain viruses, influenza virus, herpes viruses, adenoviruses that cause the common cold, can also cause pneumonia. Viruses are the most common cause of pneumonia in children under 5 years of age. Viral pneumonia is usually mild. But in some cases it can get very serious.

    Nosocomial pneumonia

    Some people get pneumonia during their hospital stay due to another illness.Hospital pneumonia can be serious because the bacteria that cause it can be more resistant to antibiotics and because the people who get it are already sick and weakened. People who are on breathing apparatus (ventilators), often used in intensive care units, are at a higher risk of this type of pneumonia.

    Pneumonia associated with medical intervention

    This is a bacterial infection that occurs in people who are in long-term care facilities or are treated on an outpatient basis, including kidney dialysis centers.Like hospital-acquired pneumonia, it can be caused by bacteria that are more resistant to antibiotics.

    Aspiration pneumonia

    Aspiration pneumonia occurs when a patient inhales food, drink, vomit, or saliva into the lungs. Aspiration is more likely if something interferes with normal gag or cough reflexes, such as brain damage, excessive alcohol or drug use.

    Risk factors

    Pneumonia can affect anyone. But in two age groups, the risk is increased:

    1. Children 2 years old or younger
    2. 90,081 People aged 65 and over

    Other risk factors include:

    • Hospital stay: increases the risk of pneumonia, especially in intensive care units of hospitals, especially with mechanical ventilation.
    • Chronic disease. Risks of getting pneumonia are increased with bronchial asthma, chronic obstructive pulmonary disease (COPD) or chronic heart disease, diabetes mellitus, liver cirrhosis.
    • Smoking. Smoking interferes with the body’s natural defenses against bacteria and viruses.
    • Weakened or suppressed immune system. People with HIV / AIDS who have undergone organ transplants, have tuberculosis and are receiving chemotherapy or long-term steroid use.

    Complications of pneumonia

    Even with treatment, some people with pneumonia, especially in high-risk groups, may experience complications, including:

    • Bacteria in the bloodstream (bacteremia). Bacteria that enter the bloodstream from the lungs can spread the infection to other organs, which can lead to dysfunction of these organs and further progression of the disease.
    • Difficulty breathing (shortness of breath). In severe pneumonia, especially in the presence of chronic lung disease, it is difficult to get enough oxygen.Hospitalization and use of a breathing apparatus (ventilator) may be required during treatment.
    • Accumulation of fluid around the lungs (pleural effusion). Pneumonia can cause fluid to accumulate in the thin space between the layers of tissue that line the lungs and chest cavity (pleura).
    • Lung abscess. An abscess occurs when pus builds up in the lungs. An abscess is usually treated with antibiotics. Sometimes surgery or drainage is required to remove the pus with a long needle or tube placed in the abscess.

    If you suspect pneumonia, you must consult a doctor!

    Not timely treatment, self-medication lead to late diagnosis, antibiotic resistance, various complications and even death.

    90,000 Pneumonia: Dangers, Symptoms, Prevention and Treatment – Biographies and References

    TASS-Dossier. Pneumonia (or pneumonia) is an acute respiratory infection that causes damage to the lung tissue. Although the disease is ubiquitous, children and families in South Asia and Africa (south of the Sahara Desert) are most affected, according to the World Health Organization (WHO).

    According to WHO statistics, this disease is the cause of death of 15% of children under 5 years of age worldwide (99% of deaths occur in poorly and moderately developed countries of the world).

    World Pneumonia Day was established to raise awareness of this issue. It has been held on November 12 with the support of WHO, since 2009. On this day, health institutions organize preventive measures, conduct medical examinations, volunteers tell people about pneumonia, distribute information leaflets and booklets.

    Symptoms

    The manifestations of the disease largely depend on the causative agent and the extent of the lesion of the lung tissue. However, almost all types of pneumonia are characterized by general symptoms: weakness and fatigue, headache, chills, a sharp rise in temperature (in the acute form of the disease), cough (in the first days – dry, then becomes wet with abundant sputum with an admixture of blood), pain in the chest (on the side of the damaged lung), shortness of breath (the larger the focus of inflammation, the stronger it is), blue skin.

    Course of the disease, complications

    Pneumonia can occur in acute, subacute (protracted) or chronic forms, in severe cases, death is possible. Mixed viral-bacterial infection aggravates the course of the disease. Depending on the involvement of the lungs in the inflammatory process, unilateral (when one lung is affected) and bilateral (both lungs) pneumonia are distinguished.

    The disease can lead to complications such as pleurisy, edema or lung abscess, acute cardiopulmonary failure, myocarditis, endocarditis, meningoencephalitis, meningitis, sepsis, infectious toxic shock, etc.

    Pathogens

    Pneumonia can be caused by various microorganisms: mainly bacteria (pneumococci, Haemophilus influenzae, staphylococci, streptococci, etc.), viruses (influenza, respiratory syncytial virus, rhinoviruses, adenoviruses, etc.), rarely fungi and parasites (ascaris, others, strongyloids and .).

    Recently, there has been a tendency to an increase in the number of atypical pneumonia caused by uncharacteristic (atypical) pathogens: for example, viruses and intracellular bacteria legionella, mycoplasma, chlamydia.

    The pathogen most often enters the lungs by inhalation, and can also penetrate the blood or lymph from other foci of infection in the body. In addition, microbes can be carried into the lungs with food particles and vomit that accidentally enter the respiratory tract.

    Risk group

    The likelihood of pneumonia increases with hypothermia, respiratory diseases, stress, overwork.

    The risk group includes small children (under 5 years old), the elderly (over 65 years old), people with a weakened immune system (for example, patients with diabetes mellitus, AIDS, cancer, etc.), with congenital defects of the bronchopulmonary system, with chronic diseases (heart disease, pyelonephritis, etc.), asthmatics, bedridden patients, as well as smokers and alcohol abusers.

    Treatment

    The main treatment for the disease is medication. Antibiotics are prescribed in the form of tablets, intramuscularly or intravenously (depending on the severity of the disease), antibacterial and antifungal drugs (if a bacterial or fungal infection is detected). If necessary, the patient is prescribed immunostimulants, mucolytic and expectorant drugs, vitamins.If necessary, oxygen inhalation may be prescribed. In most cases, with pneumonia, the patient must be admitted to a hospital – the department of therapy or pulmonology.

    During the acute period of the illness, it is recommended to stay in bed, consume warm drinks up to 1.5-2 liters per day (in the form of tea with lemon, fruit drinks, juices), exclude fatty foods and confectionery from the diet.

    Prevention

    There is no universal vaccination against pneumonia.However, there are vaccines that act against certain microorganisms: against pneumococcus, some types of streptococcus, measles and pertussis (in childhood), etc. Given that pneumonia often occurs as a complication after influenza, annual influenza vaccinations are indicated.

    For prevention, you should lead a healthy lifestyle with adequate nutrition and rest, avoid stress.

    90,000 Pneumonia Overview – Summary of Relevant Conditions

    Cough is a common respiratory symptom that can be problematic for diagnosis as it accompanies a number of diseases.[35] Madison JM, Irwin RS. Cough: a worldwide problem. Otolaryngol Clin North Am. 2010 Feb; 43 (1): 1-13, vii.
    http://www.ncbi.nlm.nih.gov/pubmed/20172252?tool=bestpractice.com
    A cough can be classified by its duration. An acute cough that lasts less than 3 weeks and is most often caused by a viral upper respiratory tract infection. A subacute cough lasts 3–8 weeks and is usually post-infectious. [36] Kwon NH, Oh MJ, Min TH, et al. Causes and clinical features of subacute cough.Chest. 2006 May; 129 (5): 1142-7.
    http://www.ncbi.nlm.nih.gov/pubmed/16685003?tool=bestpractice.com
    If the cough lasts longer than 8 weeks, a systematic approach to finding out the cause and choosing the most optimal treatment is necessary. Common causes of chronic cough (a cough that lasts> 8 weeks) in nonsmoking adults with normal chest radiographs who are not taking ACE inhibitors are upper respiratory tract cough syndrome, asthma, gastroesophageal reflux disease, and asthmatic eosinophilic bronchitis.[37] Irwin RS, French CL, Chang AB, et al. Classification of cough as a symptom in adults and management algorithms: CHEST guideline and expert panel report. Chest. 2018 Jan; 153 (1): 196-209.
    https://journal.chestnet.org/article/S0012-3692(17)32918-5/fulltext

    http://www.ncbi.nlm.nih.gov/pubmed/29080708?tool=bestpractice.com
    [38] Irwin RS, Baumann MH, Bolser DC, et al. Diagnosis and management of cough executive summary: ACCP evidence-based clinical practice guidelines. Chest.2006 Jan; 129 (1 Suppl): 1-23S.
    https://journal.chestnet.org/article/S0012-3692(15)52825-0/fulltext

    http://www.ncbi.nlm.nih.gov/pubmed/16428686?tool=bestpractice.com
    Patients with a chronic cough (usually with phlegm), fever, general malaise, chest pain and dullness of the percussion sound, weakening of breathing sounds, and wheezing on physical examination should be evaluated for pneumonia.

    Biologists have discovered one of the ways to protect cells from bacteria that cause pneumonia

    Lung inflammation (or pneumonia) can have a variety of causes and is associated with a wide range of diseases.Among them, Legionellosis is a ubiquitous infectious disease caused by the bacteria Legionella pneumophila. These microorganisms live in water, including air conditioning fluids, boilers and showers, and can parasitize some amoebas. When a person inhales infected vapors, bacteria penetrate into the lung macrophages – cells that absorb and digest pathogenic organisms. However, Legionella settle in membrane vesicles (vacuoles), which do not fuse with digestive lysosomes, and therefore are not rendered harmless by macrophages.In addition, they are able to trigger cell death, as a result of which lung damage develops with complications in all organs, which can lead to death.

    “In this work, we focused on studying the mechanisms by which macrophages respond to bacteria located both in the internal environment of the cell, in the cytoplasm, and in vacuoles. This could have been done on the model of such a socially significant disease as pneumonia, ”says Alexander Poltorak, a leading researcher at Petrozavodsk State University.

    In response to the penetration into the cytoplasm of bacteria and especially fragments of their cell wall – lipopolysaccharides – the enzyme caspase 11 is activated in the cell. It triggers a cascade of reactions leading to the rupture and death of the macrophage. Thus, the cell sacrifices itself to prevent bacteria from multiplying. In the case of pathogens living inside vacuoles, caspase 11 is not triggered; however, this is compensated for by a different mechanism. It is based on the activation of a macrophage by interferons – proteins secreted by a cell infected with viruses as a warning signal.In response, its neighbors activate their defense mechanisms in advance. In the event of a bacterial invasion, this also helps. Thus, specific guanylate-binding proteins (GBPs) begin to actively work in macrophages, which are capable of finding legionella in vacuoles and destroying them by “setting” caspase 11 on them. This is the scenario of events suggested earlier.

    Using a variety of approaches to the study of proteins and DNA and RNA, as well as microscopic methods, scientists have established that the synthesis and activity of GBPs (as well as caspase 11) are regulated by the macrophage itself.This process occurs independently of the interferons released during infection. Moreover, the last cell produces at a high level and in the absence of danger. As a result, GBPs are constantly present in the cytoplasm and are always ready to meet pathogenic bacteria. Scientists have also found that GBPs help macrophages detect and neutralize Legionella by creating leaks of their hereditary material from the vacuole, where they are inaccessible to defense systems. After such an exit, special sensory pathways are launched, and the macrophage can begin a full-fledged struggle.

    “Legionella is a convenient model for studying this group of pathologies, and a detailed examination of the mechanisms of the cell’s response to the causative agent of the infection will make it possible to choose adequate methods of treatment,” concludes Alexander Poltorak.

    The work was carried out by employees of Petrozavodsk State University together with colleagues from Tufts University (USA), Research Center on Human Nutrition and Aging (USA), Duke University Medical Center (USA), Osaka University (Japan), and Howard Hughes Medical Institute (USA).

    90,000 Our uneasy

    The death toll from the disease COVID-2019 caused by the new coronavirus SARS-CoV-2 has exceeded seven thousand people worldwide. As a rule, all of these people died from the symptoms of pneumonia, an acute respiratory illness that has been known for almost two centuries. At the request of N + 1 , the pulmonologist Vasily Shtabnitsky told about what pneumonia is, how it happens, how it proceeds and what exactly threatens the body.

    What kind of pneumonia are there?

    “Classical”, or bacterial, pneumonia was scientifically described back in the 19th century, and about the same time the first known pathogens – pneumococci – were isolated.With such pneumonia – it is also called “typical pneumonia” – an infection in the lower respiratory tract provokes inflammation and accumulation of fluid in the alveoli, exudate is formed, and respiratory failure occurs.

    Closer to the middle of the twentieth century, SARS was described, which can be provoked by many pathogens – chlamydia, mycoplasma, legionella and viruses. It does not give a clinical picture characteristic of the “classic”, it may not be accompanied by high fever, wheezing, sputum with blood.In its course, general signs of intoxication and dry cough may prevail. On radiographs, as a rule, only a fuzzy infiltration is visible.

    A discussion began among doctors, which continues to this day, on the question of whether the virus can cause pneumonia. The classical mechanism of pneumonia is associated with certain properties of bacteria, with the substances they release and with the immune response that they provoke. Against this background, viruses either do not cause pneumonia at all, or, if they do, then atypical.

    Pneumonia of this type can be called interstitial, since fluid is formed not in the alveoli, but in the interstitium, that is, in the connective tissue space between them. This contributes to the formation of a nonspecific picture when “everything is fine” in the alveoli. Such inflammation can only be seen with the help of a computed tomogram – the so-called “frosted glass” or some other interstitial pattern can be seen there.

    The gray area in the CT scan in the lower left area is the so-called “frosted glass” resulting from the COVID-2019 disease

    Department of Radiology, University of Michigan Health System

    An outbreak of Severe Acute Respiratory Syndrome (SARS) in the early 2000s, followed by the h2N1 influenza pandemic in 2009-10, caused many deaths.People were dying from what was called viral pneumonia and in some cases from acute respiratory distress syndrome (ARDS).

    What is this syndrome?

    ARDS is a nonspecific damage to the lungs that can develop in response to various stimuli – to infection, to injury, to inhalation of a substance, for example, a poisonous gas, say, chlorine, used in the First World War.

    To explain its effect, it is necessary to talk about the structure of the lungs.It is a system that transports oxygen from the air into a liquid, that is, into the blood. It is necessary to drive oxygen into the aquatic environment, and at the same time prevent the fluid from filling the alveoli. For this, there are structures in the lungs – the endothelium and the alveolar-capillary membrane, which restrain the fluid from passing into the alveoli.

    With ARDS, these structures begin to collapse, they cease to hold back the fluid, and it immediately, along the pressure gradient, fills the alveoli. The so-called noncardiogenic pulmonary edema is formed.

    Acute Respiratory Distress Syndrome (ARDS)

    With ARDS, extensive pneumonia develops, against the background of which severe respiratory failure occurs.This condition does not appear only with pulmonary pathologies, it can be the result of many life-threatening conditions.

    The conditions that have a direct damaging effect on the lungs include pneumonia, lung injury. With them, the integrity of the epithelium of the bronchi and alveoli is disrupted. This contributes to the blockage of the bronchi, collapse of areas of the lung, the development of pulmonary edema (alveolar and interstitial).

    The most common conditions in which the lungs are indirectly affected are severe infections (sepsis, peritonitis), acute pancreatitis, severe trauma, massive blood transfusions.With them, the epithelium of the pulmonary capillaries is damaged, which leads to the release of plasma and blood cells into the interstitium. As a result, the interalveolar septa become thicker, and gas exchange becomes more difficult. In the future, severe disturbances in the microcirculation of the lungs develop, the fluid goes out into the alveoli.

    Symptoms of ARDS include feeling short of breath, frequent wheezing, cyanosis, tachycardia, arterial hypertension, often accompanied by anxiety and agitation. ARDS develops within a few hours or days after exposure to a damaging factor.It is usually accompanied by a malfunction of other organs (multiple organ failure).

    Source

    In this case, the direct damaging effect of the virus plays some role. It appears to multiply in the alveolar epithelium, and the infected cells cease to function. In addition, apoptosis, programmed cell death is activated in cells, they can be destroyed by macrophages.

    But the body’s immune response also plays a very important role.The virus does not just multiply in cells, it leaves its antigen on the surface of the cell. For this antigen, the cells of the immune system recognize it as sick. The massiveness of cell damage to viruses is also important here, as well as, perhaps, the absence of some other, more targeted immunity tools. When more targeted immunity fails, “heavy artillery” is activated to help the virus destroy the lungs.

    This does not mean that if we turn off the immune system, the patient will be fine, and this does not mean that, for example, people with immunodeficiency will not suffer from such severe viral pneumonia.But, in general, the mechanism is mainly associated with the immune response.

    This happens not only in the case of pneumonia, but also, for example, in sepsis and septic shock. The severity of a person’s condition can be influenced not only by infection of the blood with bacteria, but by the reverse immune response of our body.

    ARDS with sepsis on the image of the lungs obtained using a computed tomogram

    Paolo Pelosi / Università degli Studi di Genova

    Now, if possible, explain step by step: bacteria enter the respiratory system and begin to multiply there, and then?

    Bacteria enter the lungs and continue to multiply there.Inside the alveoli in the lungs there are so-called alveolar macrophages. They get the bacteria, destroy it and expose its antigens to other immune cells that begin to study them, and at the same time release a lot of mediators that attract other cells.

    Other macrophages come to the focus of inflammation, neutrophils come there – this is already the “atomic weapon” of the immune system, destroying everything to zero. B- and T-lymphocytes come to the focus of inflammation. B-lymphocytes produce immunoglobulins that bind to bacterial antigens, which helps attract other immune cells to attack.The role of T cells here is slightly less, they are able to destroy bacteria directly.

    Bacteria are destroyed, toxic substances are released, and this leads to an increase in temperature. The arachidonic acid system is activated, prostaglandins are formed, which increases blood flow to the site of inflammation, and the rate of biochemical reactions increases. Further, if the body is strong, then it destroys it all by itself and does not allow the infection to spread.

    If the body is not strong, bacteria can multiply and transfer to other organs.Sepsis can develop: this is a condition in which bacteria enter the bloodstream. A massive release of some bacterial toxins can lead to the development of a systemic reaction: to the development of hypotension, shock.

    This is how pneumonia, provoked by a bacterial infection, works. But the mechanism is roughly the same in the case of viruses. However, compared to bacteria, the virus is more generalized, it affects many tissues, and viruses are more difficult to fight, they do not have a cell wall that can be destroyed.

    Above – healthy lungs, below – affected by “classic pneumonia”

    The virus constantly infects new cells, and they themselves become the source of the new virus. Therefore, several other mechanisms of immunity work here – just T cells, macrophages, antibodies.

    Is it true that in severe pneumonia, the lungs cease to saturate the blood with oxygen and a person dies of suffocation?

    In the case of bacterial pneumonia, structures are destroyed, the alveoli are filled with an infiltrate containing cell debris, bacteria, and cells of the immune system.Essentially, the lung turns into a liquid-filled sponge. The more part of the lung is occupied by the infiltrate, the worse the person breathes. At some point, he simply develops critical respiratory failure.

    This may be accompanied by a violation of cardiac activity, cerebral edema may form. But a decrease in the concentration of oxygen in the blood is inevitable, and it can fall to a level that is incompatible with life.

    Diagram showing the penetration of the infiltrate into the alveoli in pneumonia

    And this process can be stopped by antibiotics?

    Yes, with drugs that kill all bacteria.The immune system will simply have to clean out these dead fields with macrophages, and the patient will wait for the lungs to clear.

    But antibiotics do not give a 100% guarantee against ARDS. I myself have seen similar situations many times: with intensive antibiotic treatment, a large number of bacteria can be destroyed, which leads to the release of large amounts of toxins into the blood.

    And how does this work in the case of viruses, when there are no foreign cells?

    There are cells infected with a virus.Each virus exposes its antigens to the surface of the cell, and it becomes a target for our immune system. The immune system begins to fight with this cell, to destroy it.

    It so happens that a virus in the lungs has infected many cells, but the immune system worked weakly at first. Then, in response to massive infection, the body can overreact and destroy too many cells. From such “atomic war” at the level of the immune system, ARDS can also develop.

    It is not entirely clear why ARDS occurs more often with some viruses than with others, but the “old” SARS virus and the avian influenza virus, and even more so the new coronavirus, are capable of causing such a reaction.

    You mentioned that viral pneumonia has a different picture, that it is interstitial pneumonia. What’s the difference?

    The lungs consist of air “sacs” – alveoli, and between the groups of these sacs there is an interstitium. It can be compared to bunches of grapes, each packed in a separate bag. If you cut the tangerine, then between the slices we will find large partitions – just like between the alveoli there is this intermediate interstitial space.

    In bacterial pneumonia, the infiltrate can fill the alveoli, and in viral pneumonia, it enters the interstitial space, and this can cause serious respiratory failure. In this case, nothing can be seen on X-ray, but on CT there will be some slight changes. With coronavirus pneumonia, this is what happens: severe shortness of breath, signs of respiratory failure – and mild changes on computed tomography.

    Is there any way to stop the slide into pneumonia in the early stages? In the case of a bacterial infection, you can drink antibiotics, but in the case of a virus?

    This is a different case.There are no proven ways to prevent pneumonia, drugs for specific antiviral therapy in Russia, and we cannot recommend anything yet.

    The Chinese have described the use of chloroquine, an antimalarial drug that they claim has antiviral effects. But this data needs to be investigated. Antibiotics prophylactically, I think, should be prescribed, because no one has canceled the secondary bacterial infection. But, apparently, it does not play a big role.

    The hormones don’t seem to be working.Antiviral drugs are likely to not work either, although different options have been tried – both anti-influenza drugs and drugs for HIV infection. (For more details on the attempts of Chinese doctors to use these and other drugs, read our material “At the Bottom of the First Aid Kit.” – Note N + 1 .)

    What happens in an emergency when the lungs stop working? The ventilator can be turned on, but the lungs themselves need to absorb oxygen. What if they are filled with liquid?

    To combat hypoxemia, patients have many different methods: you can manually inflate the lungs, you can even straighten stuck together alveoli.All this works for the time being. But, probably, one of the best for today is ECMO, extracorporeal membrane oxygenation.

    We create a special membrane through which blood passes. The membrane allows oxygenation of the blood just as it is saturated when it passes through the lungs. That is, we kind of create artificial lungs, such gills.

    This can save a person, although not always. One of the randomized ECMO trials ended just last year and showed no reduction in the risk of death in patients with ARDS, although previous studies have shown it.And yet, some patients recover very quickly from ARDS; it does not give one hundred percent mortality.

    In general, you need to understand: when a patient has such a critical condition that ECMO is required, then, as a rule, the situation is not limited to the lungs alone. He develops multiple organ failure. We’re saving his lungs, but his kidneys are failing. Saving the kidneys – brain loss begins.

    Can the lungs recover, can a person return after ECMO?

    We have stem cells that are capable of restoring the lungs to one degree or another.There are, of course, certain “buts”. New lungs cannot grow, but the epithelium can change, the membrane can be restored.

    There are several ARDS scenarios. When favorable, the cells begin to regenerate. But in an unfavorable scenario, the basement membrane dies and instead of regeneration, fibrosis begins, when connective tissue begins to grow instead of cells. This is not fatal, but with fibrosis, the function of the lungs is impaired due to the fact that the architecture of the alveoli, the pulmonary lobe, is lost.

    But at the stage when it is necessary to apply mechanical ventilation, recovery of health is still possible?

    Perhaps, of course. According to statistics, at least 50 percent of patients survive. In some centers, I think, with super-examination, super-developed protocols, mortality is no more than 20-25 percent of cases.

    How long can a person live on mechanical ventilation?

    This period is not limited – if there is no damage to the lungs, a person can live their whole life on a ventilator.But usually there is a regeneration in about a month.

    That is, in the absence of antiviral agents in the fight against viral pneumonia, we can only rely on our own immune system? Hope that she crushes the infection in time and does not kill her master in the process?

    Yes. But the scenario for most cases of new coronavirus infection is as follows: 80 percent of patients suffer from it in a mild form, 15 percent in a moderately severe form. In both situations, as a rule, mechanical ventilation is not required.And only due to the most severe cases – this is 5 percent of cases – mortality is mainly increasing.

    Are these people whose immune system is not working properly – at the wrong time or too much?

    Apparently, the matter is in age. The role of angiotensin receptors is debated, because in hypertensive patients the density of these receptors in the lungs is greater, and they are a target for the virus – with a large number of these receptors, the effect of the virus increases. But this is only a theory, and the discussion about why hypertensive patients are at risk continues.Maybe this is due to comorbidity, concomitant diseases, or maybe, indeed, because of these receptors.

    From the point of view of a doctor, how important is it to know if a patient is infected with a coronavirus or not? Does this change anything in the practice of treatment?

    I think not in general. It is clear that all sorts of epidemiological measures will have to be taken. Correct triage and isolation of patients is very important. But this changes the tactics of treatment slightly.

    After a negative test for bacterial infection, we may not prescribe antibiotics in order to reduce the burden on the body.We can prepare a ventilator for the patient. Early intubation, connection to a ventilator is one of the methods of preventing severe ARDS. It is believed that ARDS flows easier in this case than if you give it a few days of spontaneous breathing.

    What advice would you give to people who begin to feel that something is wrong with them? When they don’t have a high fever, but they cough. Either they stay at home, or run for fluorography, or something else. What is the correct way to behave in this situation?

    If a person does not have risk factors associated with coronavirus infection – this is the age of 60-65 years and older, hypertension, cardiovascular diseases, diabetes mellitus, a number of other concomitant diseases – if this is, in general, a healthy young person and he feels relatively well, then he is likely to have symptoms like a common cold.

    You can notify the polyclinic. Call, say: I have a cold, consult. If they say to come, come. But I wouldn’t.

    Because now staying at home is an additional measure to prevent the spread of infection. That is, if a person feels sick, he should self-isolate as much as possible. It is most important. I cannot insist that everyone calls the clinic and demanded the arrival of a doctor. Because doctors’ resources are very limited, especially during an epidemic.

    But it would be right to notify the clinic and learn about the red flags. This is increasing shortness of breath, constantly high fever, weakness that does not allow movement, sputum with blood. These bad symptoms are a reason to call an ambulance to go to the hospital.

    But in 8 out of 10, even in 9 out of 10 people, the disease will be mild. And you just need to isolate yourself, try not to infect anyone, remember that most of the sick – according to Chinese data – are clusters in the family.When one person in a family gets sick, the whole family gets sick. Isolating the family is difficult because the person is contagious even before symptoms appear. But, for example, if guests, weddings, and other family events are planned, it is better to postpone them until the post-epidemic threshold.

    Wash your hands, wash your face, minimize meetings with people, work remotely, if possible, do not use public transport, walk, or now you can take a bike, or take a car or taxi. Don’t shake hands.Just stop all handshakes altogether. Well, and try not to use common things, such as a common mug somewhere in the office. Everything should be individual.

    Well, at the first signs of ARVI, stay at home and do not go anywhere in any case until a negative result for coronavirus infection is obtained.

    The text was prepared by Andrey Ukrainsky

    Mycoplasma pneumonia – mon-crb

    – atypical pulmonary infection caused by Mycoplasma pneumoniae.The disease is accompanied by catarrhal and respiratory manifestations (nasal congestion, sore throat, attacks of obsessive unproductive cough), intoxication syndrome (low-grade fever, weakness, headache, myalgia), dyspepsia (gastrointestinal discomfort). Mycoplasma etiology of pneumonia is confirmed by X-ray and CT of the lungs, serological and PCR studies. With mycoplasma pneumonia, macrolides, fluoroquinolones, bronchodilators, expectorants, immunomodulators, physiotherapy, massage are indicated.

    Causes of mycoplasma pneumonia

    Mycoplasma pneumonia is caused by highly virulent strains of anaerobic microorganisms of the genus Mycoplasma – M. pneumoniae. The causative agent is represented by small (in size comparable to viral particles), which do not have a cell wall (similar to the L-forms of bacteria), prokaryotic organisms. Mycoplasmas are easily adsorbed on the surface receptors of target cells (epithelial cells of the trachea and bronchi, alveolocytes, erythrocytes, etc.)) and parasitize on the membrane or inside the host cell. The integration of mycoplasma into the cell membrane or its penetration into the cell turns the latter into immunologically foreign, which provokes the development of autoimmune reactions. It is autoantibody formation that causes non-respiratory manifestations of mycoplasma infection.

    Mycoplasmas are able to persist for a long time in epithelial cells and lymphopharyngeal ring; easily transmitted by airborne droplets from sick and asymptomatic carriers with mucus from the nasopharynx and respiratory tract.Mycoplasmas are unstable in external conditions: they are sensitive to pH drops, heating and drying, ultrasound and UV radiation, they do not grow on insufficiently moist nutrient media.

    In addition to mycoplasma pneumonia, microorganisms can also cause acute inflammation of the upper respiratory tract (pharyngitis), bronchial asthma, exacerbations of chronic obstructive bronchitis and the development of non-respiratory pathology (pericarditis, otitis media, encephalitis, meningitis, hemolytic anemia) in apparently healthy people.

    The absence of a cell membrane provides mycoplasmas with resistance to β-lactam antibiotics – penicillins, cephalosporins. With mycoplasma infection, the development of local inflammation with a pronounced immunomorphological reaction, local antitelogenesis (all classes of immunoglobulins – IgM, IgA, IgG), activation of cellular immunity is noted. The symptoms of mycoplasma pneumonia are predominantly due to an aggressive inflammatory response of the host (post-infectious hypersensitivity mediated by T-lymphocytes).

    Symptoms of mycoplasma pneumonia

    The incubation period for mycoplasma pneumonia can last 1-4 weeks (usually 12-14 days). The onset of the disease is usually gradual, but may be subacute or acute. There are respiratory, non-respiratory and generalized manifestations of mycoplasma pneumonia.

    In the initial period, there is a lesion of the upper respiratory tract, which occurs in the form of catarrhal nasopharyngitis, laryngitis, less often acute tracheobronchitis.There is nasal congestion, dryness in the nasopharynx, sore throat, hoarseness. The general condition worsens, the temperature gradually increases to subfebrile values, weakness and sweating appear. In acute cases, symptoms of intoxication occur on the first day of the disease, with gradual development – only on days 7-12.

    Characterized by a prolonged (at least 10-15 days) unproductive paroxysmal cough. During an attack, the cough is very violent, debilitating, with the release of a small amount of viscous mucous phlegm.The cough can become chronic, persisting for 4-6 weeks due to airway obstruction and bronchial hyperresponsiveness. The spectrum of manifestations of mycoplasma pneumonia may include signs of acute interstitial pneumonia.

    Of the extrapulmonary symptoms for mycoplasma pneumonia, the most characteristic rashes on the skin and eardrums (like acute myringitis), myalgia, gastrointestinal discomfort, sleep disturbance, moderate headache, paresthesias. The accession of non-respiratory manifestations aggravates the course of mycoplasma pneumonia.