Persistent Low-Grade Fever in Kids and Adults: Causes and Treatme

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Long lasting low-grade fevers can occur with viral or bacterial infections, stress, or certain medications. Other health conditions like thyroid issues or autoimmune diseases can also cause this symptom.

What is a low-grade fever?

A fever is when a person’s body temperature is higher than normal. For most people, normal is roughly 98.6° Fahrenheit (37° Celsius).

“Low-grade” means that the temperature is slightly elevated — between 98.7°F and 100.4°F (37.05°C and 38.0°C) — and lasts for more than 24 hours. Persistent (chronic) fevers are typically defined as fevers lasting more than 10 to 14 days.

A fever can mean a lot of different things, but most low-grade and mild fevers are nothing to worry about. Most often, an increase in body temperature is a normal response to an infection, like a cold or the flu. But there are many other less common causes of a persistent low-grade fever that only a doctor can diagnose.

A fever alone may not be a reason to call a doctor. Yet, there are some situations where you should get medical advice, especially if a fever lasts more than a few days. The presence of a fever can mean different things for adults, infants, and children.

Adults

For an adult, a fever isn’t usually a cause for concern unless it goes above 103°F (39.4°C). You should see a doctor if you have a fever higher than this.

If your fever is lower than 103°F, but lasts for more than three days, you should also visit a doctor.

You should seek immediate medical attention if any of these signs or symptoms accompanies a fever:

• strange rash that rapidly worsens
• confusion
• persistent vomiting
• seizures
• pain when urinating
• stiff neck
• severe headache
• throat swelling
• muscle weakness
• difficulty breathing
• hallucinations

Infants

For infants under 3 months old, even a slightly higher than normal temperature can mean a serious infection.

Call your pediatrician for a low-grade fever if your baby seems unusually irritable, lethargic, or uncomfortable or has diarrhea, a cold, or a cough. In the absence of other symptoms, you should also see a doctor if a fever lasts continuously for more than three days.

Children

If your child is still making eye contact with you, drinking fluids, and playing, then a low-grade fever isn’t likely a cause for alarm. But you should still visit a doctor if a low-grade fever lasts for more than three days.

Also call your child’s pediatrician if your child:

• is irritable or appears very uncomfortable
• has poor eye contact with you
• vomits repeatedly
• has severe diarrhea
• has a fever after being in a hot car

Viral infections, like the common cold, are the most common cause of a persistent low-grade fever, but there are other less common causes to consider.

Respiratory infections

Your body naturally raises its body temperature to help kill the bacteria or virus causing an infection. Colds or the flu are caused by viruses. Colds in particular can cause a low-grade fever that lasts more than a few days.

Other symptoms of a cold include:

• stuffy or runny nose
• sore throat
• sneezing
• cough
• fatigue
• lack of appetite

Viral pneumonia and bronchitis are two other types of respiratory infections that can also cause a low-grade fever. Along with a fever, chills, and a sore throat, pneumonia and bronchitis come with a cough that persists for weeks.

In children, it’s common to experience “back-to-back” viral infections. This can make it seem like the fever is lasting longer than it should be.

Treatment for viral infections involves rest and fluids until your body takes care of the infection. You can take acetaminophen for reducing a fever if your symptoms are really bothersome. Fevers are important in helping your body fight off certain infections, so sometimes it’s best to wait it out.

If the infection is more serious, your doctor may prescribe antibiotics, antiviral drugs, or other medications to help treat the infection.

Urinary tract infections (UTIs)

Persistent fever can signal a hidden urinary tract infection in both children and adults. A UTI is caused by a bacterial infection. Other symptoms include pain and burning while urinating, frequent urination, and bloody or dark urine.

A doctor can examine a sample of urine under a microscope to diagnose a UTI. Treatment involves a course of antibiotics.

Medications

A low-grade fever can occur about 7 to 10 days after starting a new medication. This is sometimes called drug fever.

Drugs associated with a low-grade fever include:

• beta-lactam antibiotics, such as cephalosporins and penicillins
• quinidine
• procainamide
• methyldopa
• phenytoin
• carbamazepine

If your fever is related to a medication, your doctor may adjust your dosage or recommend a different drug. The fever should disappear once the medication is stopped.

Teething (infants)

Teething usually occurs between 4 and 7 months of age. Teething can occasionally cause mild irritability, crying, and a low-grade fever. If the fever is higher than 101°F, it’s not likely caused by teething and you should bring your infant to see a doctor.

Stress

A persistent fever can be caused by chronic, emotional stress. This is called a psychogenic fever. Psychogenic fevers are most common in young women and people with conditions often exacerbated by stress, such as chronic fatigue syndrome and fibromyalgia.

Fever-reducing drugs like acetaminophen don’t actually work against fevers caused by stress. Instead, anti-anxiety drugs are the therapy used to treat a psychogenic fever.

Tuberculosis

Tuberculosis (TB) is a highly infectious disease caused by a bacterium called Mycobacterium tuberculosis. Though TB is more common in developing countries, thousands of cases are reported in the United States each year.

The bacteria can remain inactive in your body for years and cause no symptoms. When your immune system is weakened, however, TB can become active.

Symptoms of active TB include:

• coughing up blood or sputum
• pain with coughing
• unexplained fatigue
• fever
• night sweats

TB can cause a persistent, low-grade fever, especially at night, which can result in night sweats.

A doctor can use a test called the purified protein derivative (PPD) skin test to determine if you’re infected with the TB bacteria. People diagnosed with active TB disease have to take several medications for six to nine months in order to cure the infection.

Autoimmune diseases

Body temperature has been found to be elevated in some people with chronic autoimmune disease, such as multiple sclerosis and rheumatoid arthritis.

In one study, researchers learned that participants with a form of MS called relapsing MS who complained of fatigue also had a low-grade fever.

A low-grade fever is also a common symptom of RA. It’s thought to be caused by inflammation of the joints.

Diagnosing RA and MS can take time and may require multiple lab tests and diagnostic tools. If you’ve already been diagnosed with RA or MS, your doctor will want to first rule out another viral or bacterial infection as the potential cause of your fever.

In case of RA- or MS-related fever, a doctor will likely recommend that you drink plenty of fluids, remove extra layers of clothing, and take a nonsteroidal anti-inflammatory drugs (NSAIDs) or acetaminophen until the fever passes.

Thyroid issues

Subacute thyroiditis is an inflammation of the thyroid gland. It can cause a low-grade fever in some cases. Thyroiditis may be caused by infection, radiation, trauma, autoimmune conditions, or medications.

Other symptoms include:

• muscle pain
• fatigue
• tenderness near the thyroid gland
• neck pain that often radiates up to the ear

A doctor can diagnose thyroiditis with an examination of the neck and a blood test that measures thyroid hormone levels.

Cancer

Certain cancers — lymphomas and leukemias in particular — can cause a persistent and unexplained low-grade fever. Keep in mind that a cancer diagnosis is rare and a fever is a nonspecific symptom of cancer. Having a persistent fever doesn’t usually mean you have cancer, but it can alert your doctor to run certain tests.

Other common symptoms of leukemia or lymphoma include:

• chronic fatigue
• bone and joint pain
• enlarged lymph nodes
• headaches
• unexplained weight loss
• night sweats
• weakness
• breathlessness
• loss of appetite

Depending on the type and stage of the cancer, a doctor may recommend a combination of chemotherapy, radiation, surgery, or other treatments.

Fevers will usually go away on their own. Over-the-counter (OTC) medications can help to lower a fever, but sometimes it’s better to ride out a low fever with fluids and rest.

If you decide to take an OTC medication, you can choose between acetaminophen and nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, aspirin, and naproxen.

For infants younger than 3 months, call your doctor first before giving them any medication.

For children, acetaminophen and ibuprofen are generally safe for reducing fever. Don’t give aspirin to children under 12 years old who are recovering from flu-like symptoms because it can cause a serious disorder called Reye’s syndrome.

If your child is younger than 12 years of age, talk to your doctor before giving them naproxen.

For teenagers and adults, acetaminophen, ibuprofen, naproxen, and aspirin are generally safe to use according to the instructions on the label.

Shop for acetaminophen and NSAIDs to help lower a fever.

Most low-grade and mild fevers are nothing to worry about.

However, you should call your doctor if you’ve had a fever for more than three days straight, or your fever is accompanied by more troublesome symptoms such as vomiting, chest pain, rash, throat swelling, or a stiff neck.

It’s hard to know when you should call a doctor for a baby or young child. In general, seek medical care if your baby is less than three months old and has any fever at all. If your baby is older than that, you don’t have to see a doctor unless the fever runs above 102°F (38.9°C) or lasts continuously for more than three days.

Continue to monitor your child’s temperature throughout the day. Rectal temperatures are usually the most accurate. Call your pediatrician’s office if you’re not sure what to do.

What Is a Low-Grade Fever? Causes, Symptoms, Treatment │ Vicks

Achy, tired, warm skin, and just not feeling right? You may have a low-grade fever. Before you figure out how to treat your low-grade fever, understand where it might have come from and what role it plays in your body.

Your body is a complex and smart system that constantly works to keep you feeling your best, including maintaining the optimum internal temperature. Your internal temperature is subject to hormonal and brain activity and adapts to conditions of your environment. For your body to work properly, your optimum body temperature is 98.6°F (37°C).¹ Sometimes, though, your body needs to elevate its temperature above that ideal level to, for example, fight off a cold or flu virus. In those cases, you might experience a low-grade fever.

Fevers are common, and they occur for a variety of reasons, often signaling that the body is working to protect itself.^2,4,5

Fevers happen for a variety of reasons and at different severity levels. Depending on your specific temperature, your fever may be categorized as low-grade fever, regular fever, or high-grade fever. The use of these terms highlights the importance of monitoring a fever.

What is a Low-Grade Fever?

A low-grade fever refers to a temperature slightly above what is considered a normal temperature. There is no standard for the specific temperature range corresponding to low-grade fever.

Regardless of the specific range that may be used to define a low-grade fever, the unifying factor for all low-grade fevers is that they represent temperatures above the ideal temperature but below what would be considered a fever.⁸

Some experts define a low-grade fever as a temperature that falls between 99. 5°F (37.5°C) and 100.3°F (38.3°C).^6,7 According to the U.S. Centers for Disease Control and Prevention (CDC), a person with temperature at or above 100.4°F (38°C) is considered to have a fever.³

What Causes a Low-Grade Fever?

Low-grade fevers can occur for several reasons and may be accompanied by other symptoms.⁹Colds and flus, for instance, are major contributors to fevers. Fevers occur more often in those who suffer from flus than in those who suffer from colds.¹⁰ However, fevers that occur in colds are more likely to be low-grade fevers, whereas fevers that occur with the flu can be low-grade or more severe.

Signs and Symptoms of Low-Grade Fever

The easiest way to determine if you have a low-grade fever—or any fever—is to simply take your temperature. However, in addition to a raised temperature, there are other signs of fever, like:³

• Warm skin
• A flushed face
• Glassy eyes
• Chills or Shivering
• Sweating
• Headache
• Muscle Aches

Depending on the underlying cause of the low-grade fever, the fever may also present with other symptoms, such as symptoms that commonly occur with fever-causing viruses like colds and flus. These symptoms—which may include coughs, sore throats, headaches, or other symptoms—can be used to help determine the reason for the fever and the best way to treat it.

How to Treat a Low-Grade Fever

The recommendations for treating a fever vary, and in the case of a low-grade fever, there are several things you can do to make yourself feel better if you are uncomfortable.¹¹ Some of these options are to:

• Rest¹²
• Drink fluids¹²
• Call a doctor if your fever is accompanied by a severe headache, stiff neck, shortness of breath, or other unusual signs or symptoms.
• Place a cold, damp washcloth on your forehead or the back of your neck while you’re resting.
• Take over-the-counter medication to treat the symptoms associated with your fever. Many over-the-counter cold and flu medicines treat multiple symptoms. Identify what other symptoms you are experiencing with a low-grade fever, if any, so you can choose a medicine that gives the relief you need. Medicines that contain acetaminophen help reduce fever. Some medicines with this active ingredient include:
• DayQuil and NyQuil: These liquid multi-symptom products also treat symptoms associated with the cold or flu, like cough, sore throat, and more. They also come in LiquiCap™ form.
• DayQuil and NyQuil SEVERE: For relief of even more symptoms, try NyQuil SEVERE, which can also help with nasal congestion, or DayQuil SEVERE, which contains an expectorant to help loosen mucus and make coughs more productive.
• FluTherapy Day and Night: Drink in tasty honey lemon flavor and breathe in the soothing Vicks Vapors. Cold and flu symptom relief—including fever—can come as a comforting medicated hot drink, too, with Vicks FluTherapy.

Consult your doctor if you are experiencing any of the below:¹³

• If your temperature reaches 104° F or higher.
• If you have fever or cough symptoms that improve, then get worse.
• If your fever is accompanied by a severe muscle pain, mental confusion, or any other out-of-the ordinary symptoms.

Low-grade fevers can come from common viruses like a cold or the flu. Taking your temperature is the easiest and most direct way to determine if you have a low-grade fever, but other signs and symptoms can also point to an increased likelihood that you are experiencing a low-grade fever.

Maintaining your health through good habits such as getting enough rest and fluids can help to minimize a fever or to reduce its duration by, for instance, supporting your immune system. In the case that you opt for medication to help relieve symptoms and reduce a low-grade fever, consider appropriate options that contain acetaminophen, a fever reducer, like DayQuil, NyQuil, and FluTherapy.

Take care of yourself, and feel better soon!

1. How is body temperature regulated and what is fever? nih.gov. https://www.ncbi.nlm.nih.gov/books/NBK279457/. Published 2009. Accessed June 11, 2020.

2. Soszyński D. [The pathogenesis and the adaptive value of fever]. Postepy Hig Med Dosw. 2003;57(5):531-554.

3. Reporting: Symptoms definitions. cdc.gov. https://www.cdc.gov/quarantine/air/reporting-deaths-illness/definitions-symptoms-reportable-illnesses.html. Accessed June 11, 2020.

4. Torreggiani S, Filocamo G, Esposito S. Recurrent Fever in Children. Int J Mol Sci. 2016;17(4):448. doi:10.3390/ijms17040448

5. Moltz H. Fever: causes and consequences. Neurosci Biobehav Rev. 1993;17(3):237-269. doi:10.1016/s0149-7634(05)80009-0

6. Thompson HJ. Fever: a concept analysis. J Adv Nurs. 2005;51(5):484-492. doi:10.1111/j.1365-2648.2005.03520.x

7. Affronti M, Mansueto P, Soresi M, et al. Low-grade fever: how to distinguish organic from non-organic forms. Int J Clin Pract. 2010;64(3):316-321. doi:10.1111/j.1742-1241.2009.02256.x

8. Chughtai AA, Wang Q, Dung TC, Macintyre CR. The presence of fever in adults with influenza and other viral respiratory infections. Epidemiol Infect. 2017;145(1):148-155. doi:10.1017/S0950268816002181

9. McGregor AC, Moore DA. Infectious causes of fever of unknown origin. Clin Med. 2015;15(3):285-287. doi:10.7861/clinmedicine.15-3-285

10. The difference between cold and flu. CDC.gov. https://www.cdc.gov/flu/symptoms/coldflu.htm. Accessed June 9, 2020.

11. El-Radhi ASM. Fever management: Evidence vs current practice. World J Clin Pediatr. 2012;1(4):29-33. doi:10.5409/wjcp.v1.i4.29

12. Fever treatment: Quick quide to treating a fever. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/fever/in-depth/fever/art-20050997. Accessed June 11, 2020.

13. Flu: What to Do if You Get Sick. cdc.gov. https://www.cdc.gov/flu/treatment/takingcare.htm. Accessed June 26, 2020.

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Subfebrile temperature – what is dangerous? What to do? Where to go in Kazan? MC Health Formula

36.6 is not a constant body temperature of a healthy person, if you monitor it during the day, then this value will fluctuate slightly. The lowest result, about 36 degrees, will be at the time of morning sleep. If a person is hot after exercise, the temperature may rise slightly

Body temperature is affected by heat, humidity, too warm clothing. In women, there is a slight jump in temperature (by half a degree) on certain days of the menstrual cycle. But it will be a one-time increase. An increase in temperature from 37.2 to 37.9 may be a cause for concern.in a period of more than a month – this is subfebrile temperature.

If subfebrile temperature lasts for more than two weeks, and it is accompanied by symptoms such as fatigue, poor sleep, shortness of breath, then the therapist should not be postponed. Often, low-grade fever signals a malfunction in the body when other symptoms have not yet appeared.

Picture taken from stock.adobe.com in the free section stock.adobe.com/en/free

Causes of subfebrile temperature

There are diseases that provoke a slight increase in temperature over a long period.

• Chronic infectious process (tuberculosis, chronic diseases of the nasopharynx, pancreatitis, cholecystitis, prostatitis, adnexitis, bacterial endocarditis, chlamydia, syphilis, HIV infection).
• Inflammatory process
• Oncology
• Autoimmune diseases (rheumatism, ulcerative colitis, drug allergy, arthritis, postinfarction syndrome)
• Parasites
• Pathologies of the endocrine system (thyrotoxicosis, severe menopause)
• Thermoneurosis (vegetative dysfunction affecting heat transfer)

If the cause of fever is an infection, then it is characterized by:

• decrease after taking an antipyretic;
• poor tolerance;
• there are fluctuations throughout the day.

But there are reasons when a healthy person has a subfebrile temperature:

• overheated
• under stress
• when taking certain drugs
• hereditary factor when a child is born and lives with a fever
• with activation of the hypothalamus
• during pregnancy
• before menstruation.

Such a temperature is not amenable to the action of antipyretic drugs, is easily tolerated and does not have pronounced daily fluctuations.

Examination will help to find out the cause.

Analyzes and studies at subfebrile temperature.

You should always start with a general practitioner. It is the general practitioner who will refer you for primary tests, and then, after the results obtained, will recommend the appointment of a narrow specialist: an endocrinologist, a cardiologist, a gynecologist, an otolaryngologist, an infectious disease specialist.

Fever for more than two weeks?

Need to submit:

• General analysis of blood and urine (increased leukocytosis, protein in urine)
• Blood for hepatitis B and C, HIV and syphilis
• Sputum culture for Mycobacterium tuberculosis
• Urine culture (genital infections) and blood culture (sepsis).

Do:

• Chest x-ray (tuberculosis, lung abscess)
• Electrocardiogram (bacterial endocarditis)
• Pelvic ultrasound (inflammatory diseases)
• Abdominal ultrasound

If, after the results obtained, the cause is not established, then the patient is sent to take a blood test:

• for hormones
• for rheumatoid factor
• for tumor markers.

Therapist of the highest category, cardiologist, gastroenterologist.
Menzhevitskaya Tatyana Ivanovna

causes and what is subfebrile temperature

01/29/2020Updated on 07/14/2021

The normal average body temperature is 36.6°C degrees Celsius. If the deviation on the temperature scale exceeds 0.5 ° C, in one direction or the other, this is not a critical indicator.

However, if the body temperature systematically rises to 37.1°C for no apparent reason, this is a reason to go to the doctor for a detailed clarification of the circumstances.

Usually, subfebrile temperature is called when the mark on the thermometer rises to 38 ° C and stays at this border. And often this is a temperature of 37.1 ° C.

In fact, an increase in body temperature does not occur from scratch.

The leading therapist of the R + Medical Network private clinic will tell you how to recognize low-grade fever and what are the most common reasons for this in medical practice.

Despite the fact that the causes of subfebrile temperature can be very different. Our doctors will still try to detail and convey the most important information to you so that you can pay attention to the hidden symptoms of the pathology in a timely manner and seek medical help. Usually, subfebrile temperature is called when the mark on the thermometer rises to 38 ° C and stays at this border. And often this is a temperature of 37.1 ° C.

What is subfebrile temperature?

Being informed is important. Especially when it comes to your own well-being or the health of loved ones.

So, body temperature can change throughout the day, depending on how you feel, climatic conditions, time of day. Therefore, deviations in the temperature regime of 0.5-1°C are not considered a pathology.

Therefore, if the temperature stays at 37.1°C for a long period, then returns to normal, and then rises again, make an appointment with a specialist. Since the real problem can be detected only after a thorough diagnosis of the body.

Causes of subfebrile temperature can be identified using a complete blood count, fluorography, ultrasound, MRI, etc. Therefore, if the temperature is 37.1 ° C for a long period, then it returns to normal, and then rises again – sign up for a consultation with specialist. Since the real problem can be detected only after a thorough diagnosis of the body.

An increase in temperature is most often an immune reaction to an inflammatory process in the body or an infection.

Thus, the immune system is actively involved in the fight against the “enemy” and signals that a failure has occurred. A virus or a focus of the inflammatory process has appeared in the body.

Therefore, it is very important not to delay the visit to the doctor, but to do it as soon as possible at the first signs of the disease. After all, any disease is always easier to prevent than to treat in the last stages of pathology.

The main causes of subfebrile temperature

The most common causes due to which the body can give temperature alarms are:

1. Anemia.
2. Intestinal parasites
3. Tuberculosis.
4. AIDS/HIV.
5. Toxoplasmosis, sepsis.
6. Oncological diseases.
7. Diseases of the thyroid gland.
8. Viral hepatitis, intestinal infection.
9. Autoimmune diseases (allergies, arthritis, ulcerative colitis, rheumatism).
10. Hormonal disorders (in pregnant women, as a variant of the norm).

By the way, the causes of a temperature of 37 ° C in women may well lie in the natural ovulation period, so if you are approaching or having your period, you should not worry about this.

Subfebrile temperature in a child. What to do?

If a teenager or young child has a subfebrile temperature, first and foremost, make sure that this is not a “temperature tail” (the result of a cold or a viral illness).

Many parents start to panic when their child has a temperature of 37°C, but at the same time they forget that the child has just recently had SARS, flu or tonsillitis.

After ARVI, a child may have subfebrile temperature for 5-14 days. And that would be the norm.

However, if the child has a subfebrile temperature and he cannot explain his condition to you, it is important to contact a competent doctor who will diagnose and determine the exact cause of the temperature increase for further correct treatment.

Normal temperature range for people of different ages

These temperature ranges can be observed in most people of all ages. Balancing these boundaries remains the norm if the temperature changes under the influence of external factors or characteristics of the organism (this should be clarified with the doctor).

However, if low-grade fever causes discomfort or is accompanied by symptoms of an unknown etiology, your task is to find the cause as soon as possible and begin effective treatment.

R+Medical Network premium class private clinic in Goloseevsky and Pechersky districts of Kyiv is distinguished by the fact that we provide patients with an integrated approach to both diagnosis and treatment of diseases.

We are not satisfied with a single indicator of tests, we are interested in a detailed analysis of the root cause of subfebrile temperature and its immediate elimination .