What are Group C Streptococci. How do they differ from other streptococcal groups. What infections can Group C Streptococci cause. How are Group C streptococcal infections diagnosed and treated. What are the potential complications of untreated Group C streptococcal infections.

Types of Streptococci: A Comprehensive Overview

Streptococcus is a diverse class of bacteria that includes both beneficial and pathogenic strains. While many streptococci play important roles in human and animal health, some can cause serious infections. The most medically significant groups are A, B, and D, with groups C and G being less common but still capable of causing illness. Let’s examine each group in detail:

Group A Streptococci (Streptococcus pyogenes)

Group A streptococci are primarily associated with:

• Pharyngitis (strep throat)
• Tonsillitis
• Sinusitis
• Otitis
• Pneumonia with empyema
• Joint or bone infections
• Necrotizing fasciitis
• Meningitis
• Endocarditis

Group B Streptococci (Streptococcus agalactiae)

Group B streptococci are known for causing infections in:

• Newborns (neonatal sepsis, pneumonia)
• Pregnant women
• Elderly individuals

Common manifestations include:

• Meningitis
• Vaginitis
• Puerperal fever
• Urinary tract infections
• Skin infections

Group D Streptococci (Enterococcus faecalis)

Group D streptococci are normally found in the human intestines. However, they can cause infections when they spread to other parts of the body, most commonly resulting in urinary tract infections.

Streptococcus pneumoniae

This type of streptococcus is primarily associated with:

• Pneumococcal pneumonia
• Meningitis
• Occult bacteremia

While S. pneumoniae is typically present in the respiratory tract, external infections can lead to pneumonia and other bacterial infections.

Group C and G Streptococci: The Lesser-Known Strains

Groups C and G streptococci are less common than the other types but are gaining attention due to their potential to cause infections. The most prevalent type in this category is Streptococcus anginosus. However, a strain called Streptococcus dysgalactiae subsp. equisimilis (SDSE) is becoming increasingly common.

SDSE shares similarities with Group A Streptococcus pyogenes and is associated with throat, skin, and soft tissue infections. While the role of Group C and G streptococci in throat infections remains somewhat controversial, they have been found in cultures of both healthy individuals and those with pharyngitis.

Infections Caused by Group C Streptococci

Group C streptococci can cause various infections, including:

Pharyngitis

Pharyngitis, commonly known as strep throat, is a bacterial infection characterized by:

• Sudden onset of sore throat
• High fever
• Pain when swallowing

The exact role of Group C streptococci in pharyngitis remains a subject of debate. While Group G has been clearly linked to pharyngitis outbreaks, the virulence of Group C in human pharyngitis is less clear. Studies have shown a higher presence of these bacteria in individuals with pharyngitis compared to healthy controls, suggesting a potential role in causing the illness.

Bacteremia

Certain Group C streptococci are strongly associated with bacteremia, a serious condition involving bacterial infection in the bloodstream. Bacteremia requires immediate medical attention and can lead to severe complications if left untreated.

Diagnosis and Treatment of Group C Streptococcal Infections

Diagnosing Group C streptococcal infections typically involves:

1. Clinical examination
2. Throat culture or rapid antigen detection test
3. Blood tests (in cases of suspected bacteremia)

Are Group C streptococcal infections treatable. Yes, these infections are generally treatable with antibiotics. The choice of antibiotic may depend on the specific strain and the severity of the infection. Common antibiotics used include:

• Penicillin
• Amoxicillin
• Cephalosporins
• Macrolides (for patients with penicillin allergies)

It’s crucial to complete the full course of antibiotics as prescribed by a healthcare provider to prevent antibiotic resistance and ensure complete eradication of the bacteria.

Potential Complications of Untreated Group C Streptococcal Infections

What happens if Group C streptococcal infections are left untreated. Untreated infections can lead to several complications, including:

• Spread of infection to other parts of the body
• Development of rheumatic fever
• Kidney inflammation (glomerulonephritis)
• Sepsis (in cases of bacteremia)

These potential complications underscore the importance of timely diagnosis and treatment of Group C streptococcal infections.

Prevention Strategies for Group C Streptococcal Infections

While it’s not always possible to prevent Group C streptococcal infections, certain measures can help reduce the risk:

• Practice good hand hygiene
• Avoid close contact with individuals who have strep throat or other streptococcal infections
• Strengthen your immune system through a healthy diet, regular exercise, and adequate sleep
• Avoid sharing personal items like toothbrushes or eating utensils

In healthcare settings, proper infection control measures are crucial to prevent the spread of streptococcal infections.

Group C Streptococci in Animal Populations

Group C streptococci are not limited to human infections. These bacteria are also found in various animal species and can cause infections in livestock and domestic animals. Some key points about Group C streptococci in animals include:

• Common in horses, causing respiratory infections and “strangles”
• Can infect cattle, leading to mastitis
• Found in pigs, potentially causing arthritis and meningitis
• Occasionally isolated from dogs and cats with various infections

The zoonotic potential of Group C streptococci, meaning their ability to spread from animals to humans, is an area of ongoing research. While direct transmission is rare, it’s important for individuals working closely with animals to practice good hygiene and take appropriate precautions.

Emerging Research on Group C Streptococci

As our understanding of Group C streptococci evolves, researchers are focusing on several key areas:

Antibiotic Resistance

Is antibiotic resistance a concern with Group C streptococci. Like many bacteria, some strains of Group C streptococci have shown increasing resistance to certain antibiotics. Researchers are monitoring this trend and investigating new treatment options to combat resistant strains.

Virulence Factors

Scientists are studying the specific mechanisms that allow Group C streptococci to cause infections. Understanding these virulence factors could lead to new strategies for prevention and treatment.

Genomic Analysis

Advanced genomic sequencing techniques are being used to better understand the genetic makeup of Group C streptococci. This research could reveal new insights into the bacteria’s evolution and potential targets for future therapies.

Vaccine Development

While there are currently no vaccines available for Group C streptococci, researchers are exploring the possibility of developing vaccines to prevent infections, particularly in high-risk populations.

Group C Streptococci in Special Populations

Certain groups may be at higher risk for Group C streptococcal infections or may experience more severe outcomes. These populations include:

Elderly Individuals

Older adults may be more susceptible to Group C streptococcal infections due to weakened immune systems and other age-related factors. They may also be at higher risk for complications such as bacteremia.

Immunocompromised Patients

People with weakened immune systems, such as those undergoing chemotherapy or with HIV/AIDS, may be more vulnerable to Group C streptococcal infections and may experience more severe symptoms.

Pregnant Women

While Group B streptococci are more commonly associated with infections in pregnant women, Group C streptococci can also cause complications during pregnancy and childbirth.

Individuals with Chronic Diseases

People with conditions such as diabetes, heart disease, or chronic lung diseases may be at increased risk for Group C streptococcal infections and related complications.

Healthcare providers should be aware of these higher-risk groups and consider Group C streptococci as a potential cause of infection in these populations.

Diagnostic Challenges and Advances

Accurately diagnosing Group C streptococcal infections can be challenging due to several factors:

• Similarity to other streptococcal infections
• Presence of the bacteria in healthy individuals
• Limitations of traditional culture methods

How are diagnostic techniques for Group C streptococci improving. Recent advances in diagnostic technologies are helping to address these challenges:

Molecular Diagnostics

Polymerase chain reaction (PCR) and other molecular techniques can quickly and accurately identify Group C streptococci, even in small quantities.

MALDI-TOF Mass Spectrometry

This technology allows for rapid identification of bacteria based on their protein profiles, helping to distinguish between different streptococcal groups.

Improved Culture Techniques

Enhanced culture media and methods are being developed to better isolate and identify Group C streptococci from clinical samples.

These diagnostic advances are crucial for timely and accurate identification of Group C streptococcal infections, enabling prompt and appropriate treatment.

The Global Impact of Group C Streptococci

While Group C streptococci are less common than some other streptococcal groups, their impact is felt worldwide. Some key points about the global presence of Group C streptococci include:

• Prevalence varies by region, with some areas reporting higher rates of infection
• Outbreaks have been documented in various settings, including hospitals and long-term care facilities
• The economic burden of Group C streptococcal infections, while not as well-studied as other streptococcal groups, is likely significant

Global surveillance efforts are ongoing to monitor the spread and evolution of Group C streptococci. These efforts are crucial for understanding the changing epidemiology of these bacteria and developing effective control strategies.

Future Directions in Group C Streptococci Research and Management

As our understanding of Group C streptococci continues to grow, several areas are likely to be focal points for future research and clinical management:

One Health Approach

Given the presence of Group C streptococci in both humans and animals, a One Health approach that considers the interconnections between human, animal, and environmental health may provide valuable insights.

Personalized Treatment Strategies

As we learn more about the genetic diversity of Group C streptococci, there may be opportunities to develop more targeted, personalized treatment approaches based on the specific strain causing an infection.

Improved Rapid Diagnostics

Continued development of rapid, point-of-care diagnostic tests could help healthcare providers quickly identify Group C streptococcal infections and initiate appropriate treatment.

Novel Therapeutics

Research into new antibiotics and alternative treatment strategies (such as bacteriophage therapy) may provide additional options for managing Group C streptococcal infections, particularly in cases of antibiotic resistance.

By advancing our understanding of Group C streptococci and developing new strategies for prevention, diagnosis, and treatment, we can better manage these infections and reduce their impact on human and animal health.

What Is Group C Streptococci?

Content

• Overview
• What are the types of streptococci?
• What infections are caused by group C streptococci?
• Does strep group C need to be treated?
• The lowdown
• FAQs

Nearly everyone has heard of strep throat and the bacteria that causes it—streptococci. But did you know that there are different types of streptococci bacteria, or they can cause other types of infection too? Group C is one of the more elusive forms of streptococci and among two strains we know little about.

In this post, we’ll explain what you need to know about group C streptococci.

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Streptococcus¹ is an entire class of organisms. Many of these bacteria play an important role in both animals and humans. Several of them, however, cause illnesses that need medical treatment. The most well-known of these medically significant groups of streptococci are groups A, B, and D, with groups C and G causing less common illnesses. Below is a breakdown of each of these types of streptococci bacteria.

Group A

Also known as streptococcus pyogenes, group A streptococci are most commonly associated with pharyngitis and tonsillitis. Streptococcal pharyngitis is the medical term for strep throat. Although other forms of streptococci can lead to the condition, group A is the most common culprit.

This group can also be responsible for sinusitis, otitis, mastoiditis, pneumonia with empyema, joint or bone infections, necrotizing fasciitis or myositis, meningitis, and endocarditis.

Group B

This group of streptococci, otherwise known as streptococcus agalactiae², is most commonly associated with neonatal infections. Its effect on susceptible populations, such as pregnant women, newborns, and the elderly, remains a high source of mortality in those groups.

While group A is commonly associated with pharyngitis, group B more commonly manifests as meningitis, neonatal sepsis, pneumonia in infants and vaginitis, puerperal fever, urinary tract infection, or skin infection in adults.

Group D

An example of streptococci that are a normal part of the microbial flora in the human body is enterococcus faecalis³, or group D streptococci. This type of bacteria normally lives in your intestines, where they pose no threat.

However, when the bacteria make their way to other parts of the body, they can cause serious infections. The most common form of infection caused by group D streptococci is urinary tract infection.

Streptococcus pneumoniae

As the name implies, streptococcus pneumoniae is most commonly associated with pneumococcal pneumonia. It can also cause meningitis and occult bacteremia. Like group D streptococci, S. pneumoniae is a normal part of the microbial flora in the body.

This type is normally present in the respiratory tract. However, infection from the outside can cause pneumonia and other bacterial infections.

Groups C and G

Streptococci groups C and G are rarer than the other types. The most common type is streptococcus anginosus, though one form of them — the streptococcus dysgalactiae subsp. equisimilis (SDSE) — is becoming more common. This strain of bacteria is similar to the group A Streptococcus. pyogenes, commonly associated with throat, skin, and soft tissue infections.

Although the relation of group C and G streptococci to skin and soft tissue infections is clear, there is some doubt about their role in throat infections. While the bacteria have shown up in cultures of people with pharyngitis, they also show up in the throats of healthy people.

Group C streptococci can cause a variety of infections, including the following:

Pharyngitis

Pharyngitis is a type of sore throat caused by a bacterial infection. Infection from streptococci bacteria is typically referred to as strep throat.

Pharyngitis⁴ is associated with a sudden onset of sore throat, high fever, and pain when swallowing. As a bacterial infection, it’s typically spread through direct person-to-person contact.

As mentioned earlier, the exact role of group C streptococci in pharyngitis remains controversial. Although group G has been clearly linked⁵ to outbreaks of pharyngitis, the virulence of group C in human pharyngitis remains unclear.

While studies have shown the bacteria to be present in healthy people and people with pharyngitis, they are found at a higher rate in those with the illness than in the control group. The bacteria’s similarity to group A lends further evidence to its role in virulence.

Bacteremia

Certain streptococci bacteria in group C are highly associated with bacteremia⁶. This is a dangerous condition that refers to an infection of bacteria in the blood. Bacteremia requires the urgent administration of antibiotics, as a delay in treatment increases the mortality risk of people with it.

People most susceptible to bacteremia infection from group C streptococci are those who already have certain underlying conditions. Depending on the series of bacteria, up to 70% of patients have malignancy, cardiovascular disease, diabetes mellitus, or immunosuppression.

Maternal and neonatal infections

Several types of group C streptococci bacteria can be found as a normal part of a woman’s genitourinary flora. Despite this, the bacteria has been attributed to several outbreaks of puerperal fever.

Also known as postpartum infection⁷, puerperal fever caused by group C streptococci is rare. The known incidents were believed to have been caused by environmental factors because the bacteria was traced back to a toilet seat and a bathtub plug.

Infection in infants is also rare. There have been a few cases of meningitis in newborns caused by group C streptococci, but infections of this sort are not common.

Infections of the skin and soft tissue

Many skin and soft tissue infections can be caused by group C streptococci, including pyoderma, cellulitis, erysipelas, surgical wound infections, abscesses, necrotizing soft tissue infections, and pyomyositis. Among these, cellulitis and erysipelas are particularly common, with group C being responsible in equal or greater frequency than group A.

Group C streptococci can also cause more serious skin infections. These infections include necrotizing fasciitis, Fournier’s gangrene, and necrotizing myositis. Here, the dangers of group C clearly outweigh those of group A. Group C is associated with a 33% mortality rate compared to only 11% for group A. These more dangerous infections typically occur in older people with comorbidities.

Streptococcal arthritis

Bacteria in the streptococci family can also cause an infection in the joints, which results in infectious arthritis. More specifically, streptococcal arthritis. According to the John Hopkins Arthritis Center⁵, streptococcal arthritis goes away when the underlying infection that’s causing it clears up. Although this usually happens within 3–12 months, it can last longer for most.

A group of hospitals in France published the occurrence of various streptococci strains in infectious arthritis patients. SDSE was found in 12% of patients and S. anginosus in 11%. These incident rates were second only to the group B type S. agalactiae.

As we’ve seen, several members of group C streptococci are normal parts of the human microbial flora. So their presence does not mean a course of treatment must be pursued. However, treatment is recommended if the bacteria has caused an infectious illness.

The typical treatment for group C streptococci is the antibiotic penicillin. The need for treatment grows more urgent when the bacteria is causing life-threatening conditions, such as bacteremia or one of the deadly skin infections.

Although less common as a cause of illness than some other groups, infection with strep group C can cause various adverse medical conditions. Some of these conditions can be life-threatening, particularly in older or immunocompromised patients. Group C infections can be treated with prescription antibiotics, most commonly penicillin.

If you believe you may have one of the conditions described above, make an appointment with your doctor. They’ll be able to help determine the cause of your illness and which, if any, strep groups are playing a role in it.

Is strep C serious?

Strep group C can cause a range of different illnesses. Some of the infections that the group can cause are quite serious. These include infection of the blood, known as bacteremia, and several skin infections that can be deadly. If you aren’t feeling well, it’s always best to see a doctor to rule out serious illness.

Is strep group C contagious?

Yes. Strep group C can spread from person to person as a bacterial infection. Although most forms of group C are spread this way, it’s also possible for the bacteria to spread to humans through animal contact, such as contaminated meat products.

What does C mean on a strep test?

Streptococci bacteria can be split into several groupings. The groupings are differentiated by letter. If you see the letter C on a strep test, the bacteria causing your infection comes from streptococci in group C.

The Different Types of Streptococci (Strep Bacteria)

Although strep throat is a common form of infection from streptococcal bacteria, it is not the only kind. Streptococcal infections are any type of infection caused by the streptococcal, or “strep” group of bacteria.

There are a number of different streptococci, which create symptoms ranging from a mild throat infection to a life-threatening infection of the blood or organs. Anyone can be affected, from babies and small children to older adults.

Most strep infections can be treated with antibiotics.

Streptococci infections are divided into several groups: Group A streptococcus, Group B streptococcus, Group C streptococcus, and Group G streptococcus.

Group A Streptococcus

Group A strep, sometimes called GAS, tends to affect the throat and the skin. People may carry GAS in these areas yet not show any symptoms of illness. Most group A strep infections cause relatively mild illness, but on rare occasions, these bacteria can lead to severe and even life-threatening disease.

Group A strep infections spread through direct contact with mucus from the nose or throat of infected persons or through contact with infected wounds or sores. (1) Illnesses from group A strep infection include:

Strep Throat In general, strep throat is a mild illness, but it can be very painful. Symptoms include sore throat that comes on very quickly, pain when swallowing, fever, red and swollen tonsils (sometimes with white patches or streaks of pus), small red spots on the roof of the mouth, and swollen lymph nodes in the front of the neck. Strep throat may also be accompanied by headache, abdominal pain, nausea, or vomiting, especially in children. Illness typically manifests two to five days after exposure.

A doctor cannot tell if someone has strep throat just by looking, so a diagnostic test is needed. A rapid strep test involves swabbing the throat and running a lab test to see if GAS is the cause of the illness.

While most sore throats are caused by viruses, strep throat is caused by bacteria and therefore can only be treated with antibiotics.

While anyone can get strep throat, it’s more common among school-aged children 5 through 15. Parents and adults who are often in contact with children of these ages are more likely to get strep throat than adults who are not. (2)

Scarlet Fever Also referred to as scarlatina, scarlet fever is a relatively mild illness characterized by a very red sore throat, a red rash that has a sandpaper feel, and a “strawberry,” or red and bumpy, tongue. Other symptoms can include fever, swollen glands in the neck, whitish coating on the tongue, and bright red skin in the underarm, elbow, or groin.

The illness typically begins with a fever and sore throat. The rash — caused by a toxin made by group A strep bacteria — usually appears a day or two later, although it can begin before the illness or up to seven days later.

Scarlet fever is highly contagious. It can be spread from person to person when someone who is infected coughs or sneezes: the bacteria travels in small droplets in the air. You can get sick by breathing in those droplets or by touching something that the droplets have landed on and touching your nose or mouth. Drinking from the same glass or eating from the same plate as an infected person can also spread the illness. It is also possible to get scarlet fever sores on the skin caused by GAS.

Scarlet fever is treated with a course of antibiotics. Complications sometimes occur and can include abscesses around the tonsils, swollen lymph nodes in the neck, and sinus and ear infections. Other, more rare complications can affect the heart, including rheumatic fever and kidney disease.

Like strep throat, scarlet fever is more common in children than adults, particularly those ages 5 through 15. Close contact with someone who has the infection is the biggest risk factor for getting the illness. There is no vaccine for scarlet fever, but people can protect themselves by practicing good hygiene, including using a tissue to cover your mouth when sneezing or coughing, washing hands frequently, using alcohol-based hand sanitizer if soap and water are unavailable, and coughing or sneezing into your upper sleeve or elbow rather than your hands if a tissue is not available. (3)

Impetigo This is an infection of the top layers of skin that typically starts when bacteria gets into a cut, scratch, or insect bite. It is usually caused by the bacteria Staphylococcus aureus but can also be caused by group A strep. It is most common among children ages 2 to 6.

Symptoms begin as itchy red or pimple-like sores surrounded by red skin, usually on the face, arms, or legs, that are filled with pus. Impetigo is contagious and can be spread by contact with sores or nasal discharge of an infected person. It can be treated with a round of antibiotics. (4)

Post-Streptococcal Glomerulonephritis Also referred to as PSGN, this is a kidney disease that can develop after a GAS infection — but PSGN is not a GAS infection of the kidneys. It’s a result of the body’s immune system fighting off the group A strep infection. PSGN usually occurs 10 days after strep throat or scarlet fever and about three weeks after a GAS skin infection.

Symptoms of PSGN include dark, reddish-brown urine, swelling in the face, hands and feet, decreased amount of urine or decreased need to urinate, and fatigue.

The condition is treated by managing symptoms, including limiting salt and water intake or prescribing medication to reduce swelling. Antibiotics can also help kill any strep A bacteria left in the body.

Most people with PSGN recover within a few weeks, but in rare instances long-term kidney damage, including kidney failure, can occur. (5)

Group B Streptococcus

Group B streptococcus, also known as group B strep or GBS, is a type of bacteria that can cause illness in people of all ages, though it can be particularly severe in newborns, most commonly causing sepsis, pneumonia, and meningitis. In adults, the most common health issues caused by GBS include urinary tract infections, skin infections, bloodstream infections, pneumonia, skin and soft-tissue infections, and bone and joint infections.

In babies, group B strep infections occur as either early-onset or late-onset. Early-onset occurs in babies younger than 1 week old, and the infection is most often passed from mother to baby during labor. Symptoms of GBS infection in newborn babies usually develop within the first few hours or days of giving birth and include being floppy or unresponsive, poor feeding, grunting when breathing, and unusually fast or slow breathing and heartbeat.

Antibiotics given to the mother during labor can help prevent the spread of the infection to the baby.

Late-onset group B strep infection in babies can occur at 1 week through 3 months old. A GBS infection is sometimes passed from mother to baby, but it can also come from another source.

Early-onset used to be the most common type of group B strep infection in newborns, but because of prevention efforts, both early-onset and late-onset occur at similar low rates, according to the Centers for Disease Control and Prevention (CDC).

In adults, group B strep infection occurs less frequently than in babies, but it can affect anyone. The sources of disease caused by GBS in adults are unknown, but the bacteria are present in both the gastrointestinal and genitourinary tracts, and may be the source of infection.

If the infection leads to sepsis or pneumonia, it can be fatal. On average, 1 in 20 nonpregnant adults with an invasive strep B infection dies, the CDC reports. The chance of GBS infection increases with age. Younger adults who do not have any other medical conditions have a lower risk of death from GBS. (6)

Group C and G Streptococci

Group C and G streptococci are much less understood than strep A and B because the diseases caused by these bacteria are far less common.

Group C and G strep most commonly live in animals such as horses and cattle and can spread to humans through raw milk or contact with these animals. The bacteria can also live in people’s throats and on human skin, particularly in areas damaged by conditions like eczema or on mucous surfaces, such as the vagina or bowel.

Infections can be treated with antibiotics, but severe infections can be fatal, especially when they have entered the bloodstream. (7)

Resources We Love

1. Centers for Disease Control and Prevention
2. Mayo Clinic
3. Cleveland Clinic
4. Familydoctors.org

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Serogroup B streptococci (GBS) have long been known to cause mastitis in cattle and small cattle and have been named Streptococcus agalactiae . Previously, until 1937 inclusive, this microorganism was considered as a commensal of the human body. Since the 60s, this species, as a human pathogen, has occasionally begun to be isolated in a variety of nosological forms of infection: endocarditis, pyelonephritis, meningitis, pneumonia, abscess, peritonitis, generic sepsis, neonatal sepsis, pharyngitis, etc. Within 1970s–1980s GBS is becoming one of the most common causative agents of purulent-septic infections in newborns and mothers in the United States and Western Europe. In the early 90s, the first publications about the role of this type of streptococcus in the pathology of pregnancy and pyoinflammatory diseases of newborns also appeared in our country. To date, official registration of diseases caused by this microorganism in the Russian Federation has not been carried out.

Streptococci of this species, according to the modern nomenclature according to the Bergay determinant, are included in the genus Streptococcus family Sreptococcaeae species S.agalactiae . The modern classification of streptococci is based on the division into serological groups according to the Lensfield classification. S.agalactiae are assigned to serogroup B and are its only representatives. GBS is a heterogeneous population consisting of a number of serotypes and their combinations. Currently, 9 serotypes have been identified, designated by Roman numerals: I, II, III, IV, V, VI, VII, VIII. Type I is divided into subtypes Ia and Ib.

The habitat of the pathogen is the human body, large and small cattle, the possibility of its transmission from animals to humans and vice versa has not been proven. The localization of GBS in humans is the gastrointestinal tract (colon), vagina, urethra, sometimes the microorganism can colonize the pharynx. Pathogenicity factors: the ability to adhere and invade, resistance to phagocytosis, hemolysin, hyaluronidase, peptidase (impairs the chemotaxis of polymorphonuclear leukocytes to the site of GBS infection).

GBS can cause severe infections in people. The most sensitive to them are newborns, pregnant women, diabetics, chronic patients, children with dystrophy, the elderly, people with reduced immunity. Spontaneous abortions, preterm labor, chorioamnionitis, pyelonephritis, urinary tract infections, endocarditis, sepsis, as well as complications after caesarean section, meningitis, mastitis and endometritis in puerperas can be associated with GBS. In neonates, GBS mainly causes sepsis, meningitis, and pneumonia. Transmission of the pathogen to the newborn can occur intranatally and postnatally. According to foreign sources, in recent years there has been a relative increase in the number of diseases caused by GBS in the elderly against the background of a slight decrease in the incidence among newborns. The observed phenomenon is associated, on the one hand, with the active prevention of this infection in maternity hospitals, and, on the other hand, with an increase in the number of elderly patients with reduced immunity. In the latter, GBS usually causes infection of the skin and bones, sepsis without a clear source of its origin, urosepsis, pneumonia, and peritonitis. Often these infections occur repeatedly in such patients.

An important role in the development of GBS infections in newborns is played by factors predisposing to the disease, the so-called “risk factors”, which can be conditionally divided into two groups:

• associated with the peculiarities of childbirth or colonization of mothers with GBS;
• directly related to newborns.

The first group includes the presence of GBS on the mucous membrane of the cervix in pregnant women, the massiveness of colonization (isolation of the pathogen simultaneously from several examined loci), cases of GBS infections in children in anamnesis in parturient women, preterm labor, prolonged anhydrous period, fever during childbirth, chorioamnionitis, bacteriuria due to GBS.

The second group includes the fact and massive colonization of newborns with GBS, prematurity and low birth weight, birth by caesarean section, intrauterine instrumental examination of the fetus, lasting more than 12 hours.

Penicillin is still the most effective and widely used drug for the treatment of infections caused by streptococci. Along with serogroup A streptococci, GBS retain their sensitivity to this antibiotic, although GBS strains in a small number of cases are resistant to penicillin G. In addition to penicillin, streptococci have been found to be highly sensitive to ampicillin, erythromycin, clindamycin, lincomycin, oxacillin and meroponem. The first three generations of cephalosprins, with the exception of cefoxitin and moxalactam, have a wider spectrum of activity than penicillin. The high sensitivity of GBS to a number of relatively new drugs with a wide spectrum of activity was also noted: thienamycin, mezlocillin, azlocillin and piperacillin. GBS strains have been found to be frequently resistant to aminoglycoses, nalidixic acid, tetracycline, chloramphenicol, bacitracin, trimethoprim, and metromnidazole. Nevertheless, the combined use of aminoglycosides with penicillin or ampicillin in experimental studies on laboratory animals revealed a synergistic effect of such combinations. In recent years, foreign literature reports on the isolation of GBS strains resistant to beta-lactam antibiotics. The nature of this phenomenon is associated with the appearance in the cells of microorganisms of the genes responsible for the synthesis of penicillin-binding proteins (PBPs). According to a number of foreign researchers, the number of GBS strains resistant to erythromycin can range from 5.9up to 32.0% and the number of strains resistant to clindamycin from 6.9 to 14.3%. The use of therapeutic bacteriophages for the prevention and treatment of GBS infection is currently impossible due to the lack of active specific bacteriophages.

Indications for examination. Birth of a child with a history of GBS infection in a woman in labor, GBS bacteriuria during this pregnancy, threatened preterm labor, fever during labor (≥ 38°C), waterless period lasting more than 18 hours.

Material for research. Blood, CSF, sputum, fetal fluid, joint fluid, tissue fragments, oropharyngeal swabs, vaginal swabs/scrapes, rectal swabs.

Etiological diagnosis includes isolation of the pathogen and identification of its DNA.

Comparative characteristics of laboratory diagnostic methods. Isolation of the pathogen in the diagnosis of GBS infections is the “gold standard” and is an important step in a series of diagnostic measures. A standard culture is used using, for example, 5% blood agar. Timely isolation of the pathogen with the determination of sensitivity to antibiotics largely determines the effectiveness of the treatment and prevention of this disease.

If an infection is suspected, a variety of biological material is examined. In the case of determining the carriage of GBS in pregnant women, smears from the mucous membrane of the vagina and rectum are examined for 35–37 weeks. pregnancy. If it is not possible to inoculate immediately, transport media may be used. The time needed to isolate and identify GBS is usually 4 to 5 days.

Identification of a specific DNA fragment S.agalactiae by PCR is carried out in the study of various biological material. Scrapings of epithelial cells from the side walls of the vagina, perianal smears at 34–36 weeks of gestation are examined to detect colonization of the vagina and/or rectum by S.agalactiae; blood, CSF of a newborn – for the diagnosis of septic conditions; swabs from the oropharynx – in newborns with clinical symptoms of pneumonia to confirm the diagnosis. The advantage of this study is that it allows testing within a few hours and thereby accelerates clinical decision-making on the prevention and treatment of the disease. The diagnostic sensitivity of the study is 81%, the diagnostic specificity is 97.6%. Detection of S.agalactiae DNA by PCR can be performed in a qualitative and quantitative format. The quantitative format of the test allows the study to be used to assess the degree of GBS colonization of a selected locus. However, the detection of a specific DNA fragment S.agalactiae by PCR does not allow the detection of viable microorganisms and, accordingly, their sensitivity to antibiotics.

Group A streptococci in children: how the infection is transmitted and when to contact the pediatrician

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Group A Streptococcus (GAS), also known as Streptococcus A or Streptococcus pyogenes , is a common bacterium. It is usually found in the throat and on the skin and may be present without causing symptoms.

Group A streptococcus is responsible for common infections such as pharyngitis, scarlet fever, impetigo and cellulitis which are easily treated with antibiotics. Rarely, this bacterium enters the lungs, blood or skin, infecting deep areas of the muscles, causing serious infections known as invasive GAS infection . In exceptional cases, the disease can lead to deaths.

Although GAS infections are rare, in recent months there have been increased cases in the United Kingdom, the Netherlands, France, Ireland and Sweden , especially among children under 10 years of age and, unfortunately, in some cases with a fatal outcome. Until now, the reason for this increase in the number of cases of streptococcal infections is unknown.

How is group A streptococcal infection transmitted?

CHA infection is spread by direct (close) contact with an infected person, by coughing and sneezing, or by contact with broken skin.

Some people can carry the bacteria without getting sick or showing symptoms of the infection, and although they can pass the infection on to others, this is less of a risk than when a person has a GAS infection.

Mild group A streptococcal infections

CHA infection causes skin and respiratory problems. The most frequent infections are pharyngitis, tonsillitis, scarlet fever, impetigo and cellulitis. These infections may cause discomfort and be accompanied by fever and malaise, but rarely cause complications. With 90,067 antibiotic treatment, 90,068 people with mild disease stop being contagious within 24 hours of starting treatment and get better within 24-72 hours.

In a person from GAS pharyngitis or tonsillitis Sore throat, often accompanied by fever.

Scarlet fever is a skin rash consisting of very small, pinkish bumps that usually start on the chest and abdomen and then spread throughout the body. They don’t usually itch, but make the skin rough, like sandpaper.

Invasive streptococcal infection (group A)

When the bacterium enters the bloodstream, lungs, or deep under the skin, it can cause a serious infection. This infection is known as Invasive GAS infection (iSGA). The most common manifestations of iSGA are necrotizing fasciitis, pneumonia, sometimes accompanied by pleural effusion and lung necrosis, streptococcal toxic shock and streptococcal sepsis.

When to go to the pediatrician?

You should contact your pediatrician if your child has some of the signs and symptoms of suspected CHA infection:

• high fever and sore throat without sputum or cough.