Among the 18 species and 8 related groups of bacteria classified as the most important human pathogens, streptococci play a special role. By medical significance, they rank second after staphylococci. The number of streptococci pathogenic to humans since the mid-1980s. In the twentieth century, in many countries of the world, the incidence of β-hemolytic group A streptococci (BHCA, S. pyogenes ) increases.

Group A beta-hemolytic streptococcus (pyogenic streptococcus, BHCA S. pyogenes) is a non-spore-forming, stationary, Gram-positive microorganism. It grows on blood agar, has a pronounced hemolytic activity, negative catalase, sensitive to bacitracin. It is found everywhere, often colonizes the skin and mucous membranes of a person. The main routes of transmission are air, contact and food. The pathogenesis of diseases is associated with the production of toxins: hemolysin, streptolysin, streptokinase A and B, deoxyribonuclease, hyaluronidase. The main nosoforms are superficial (tonsillitis, pharyngitis, impetigo, erysipelas), invasive (necrotizing fasciitis, myositis, meningitis, endocarditis, pneumonia, postpartum septicemia) and toxic mediated infections (scarlet fever, toxic shock syndrome). The occurrence of neurological disorders in children with obsessive-compulsive disorder (PANDAS syndrome) is also associated with streptococcal infection.

Streptococcus pyogenes remains 100% sensitive to β-lactam antibiotics (penicillins, cephalosporins, carbapenems). They remain the only class of antibiotics to which S. pyogenes has not developed resistance. An urgent problem is resistance to macrolides, which in some regions of the world exceeds 30%. A multicenter study of the resistance of S.pyogenes clinical strains, carried out in 2000-2001, allowed us to study the prevalence of resistance, mainly to macrolides, in different regions of USA. The frequency of resistance to erythromycin varied and reached 11.4%, while no strain resistant to telithromycin, representative of a new class of antibiotics, ketolides, was found. In almost 90% of cases, resistance to macrolides was due to the methylation of ribosomes, in other cases, it was associated with the active elimination (efflux) of the antibiotic from the cell.

Streptococcal tonsillopharyngitis (sore throat) is an acute general infectious disease with a predominant lesion of the lymphoid and pharyngeal mucosa caused by GBSA. By recurrent streptococcal tonsillopharyngitis, we have to understand several episodes of the disease over several months with positive results of bacteriological methods and / or rapid diagnosis for HBAS, negative research results between episodes of disease and an increase in anti-streptococcal antibody titers after each case of disease.

Etiology: Among the bacterial pathogens of acute tonsillopharyngitis, GBSA is of the utmost importance.

Epidemiology. In the United States, 1 to 1.4 million cases of tonsillopharyngitis of BHCA etiology are diagnosed each year. Transmission is carried out by airborne droplets, by contact and by food. The sources of infection are the patients, less often the asymptomatic carriers. The probability of infection increases with high seeding and close contact. HBAS can cause large outbreaks of tonsillopharyngitis in organized groups. Most often, children aged 5 to 15 are sick. The highest incidence is in the winter-spring period.

Clinical picture: The incubation period is from several hours to 2-4 days. A sudden onset is characteristic with an increase in body temperature to 37.5-39 ° C, general intoxication is expressed. The sore throat is so severe that the patient is swallowed. On examination, redness of the palatal arches, tongue and posterior pharyngeal wall is revealed. The tonsils are hyperemic, swollen, often with a purulent coating of yellowish white color. The coating is loose, porous, easily removed with a spatula from the surface of the tonsils without bleeding defect. All patients have regional lymphadenitis.

Blood: leukocytosis, a shift in the leukocyte formula to the left, an increase in ESR, the appearance of a C-reactive protein.

The duration of the peak period (without treatment) is 5 to 7 days. In the future, in the absence of complications, the main clinical manifestations of the disease quickly disappear.

Complications. Complications of streptococcal tonsillopharyngitis are particularly dangerous, which are divided into:

Diagnostics. It is extremely important to establish the etiology of tonsillopharyngitis in a timely manner, because, with rare exceptions, only angina pectoris of streptococcal etiology requires antibacterial therapy. The diagnosis includes a microbiological examination of the smear from the surface of the tonsils and / or the posterior pharyngeal wall. Abroad, rapid diagnostic methods based on direct detection of the streptococcal antigen in smears from the surface of the tonsils and / or posterior pharyngeal wall are widely used. Modern test systems allow you to obtain the result after 15-20 minutes with a high specificity (95-100%), but less than the sensitivity during cultural studies (60-95%), and therefore a negative result of the rapid test must always be confirmed by cultural research.

The goal of antibiotic therapy for acute streptococcal tonsillitis is the eradication of HBSA, which not only eliminates symptoms of infection, but also prevents early and late complications, and also prevents the spread of infection.

Choice of antibiotics. First-line drugs for the treatment of acute streptococcal tonsillitis are penicillin (phenoxymethylpenicillin), aminopenicillins, and oral cephalosporins. In patients with a proven allergy to β-lactam antibiotics, macrolides should be used and with an intolerance to them - lincosamides.

BSAA transport. On average, around 20% of school-aged children are carriers of HS in spring and winter. Given the low risk of developing purulent and non-purulent complications, as well as an insignificant role in the spread of HBSA, chronic carriers, as a rule, do not need antibiotic therapy.

Rheumatic fever (ARF) can occur both after tonsillopharyngitis with a typical clinical picture and after asymptomatic infection or with mild symptoms. ENT occurs only after infections of the pharynx, and never after infections of the skin and soft tissues. A possible explanation for this phenomenon is the difference in immune response to skin and pharyngeal infections and in the absence of rheumatological potential in the strains causing skin infections. The risk of developing an ENT after untreated tonsillopharyngitis is 1%. Streptococcus rheumatogen M serotypes include 1, 3, 5, 6, 18, 19, 24.

Currently, in developed countries, rheumatic fever occurs with a frequency of 0.5 per 100,000 school-age children. In developing countries, the incidence is 100 to 200 per 100,000 school-age children, each year 10 to 15 million new cases of acute respiratory infections, which is the leading cause of death from cardiovascular disease.

It should be noted that an unjustified delay in the restoration of disability, weakness, unstable subfebrile state, arthralgia, palpitations and a slightly elevated ESR persisting after tonsillitis, in combination with an increase in anti-streptococcal antibody titers (anti-streptolysin O, anti-streptokinase, anti-streptokinase, anti-streptogialuronovidase onset of rheumatic fever.

In accordance with WHO recommendations for the diagnosis of rheumatic fever, the Jones criteria, as revised by the American Heart Association in 1992 (see table), are applied as international criteria. The presence of two major criteria, or one large and two small, in combination with data documenting previous HCVI infection, indicates a high probability of acute respiratory infections. However, not a single diagnostic criterion is strictly specific to RAD; therefore, difficulties in early recognition of the disease and differential diagnosis with other nosologies remain.

Rheumatic heart disease - the main syndrome of acute respiratory infections. It is characteristic: a chronological link with a BSA infection of the pharynx (sore throat), a latency period of 2 to 4 weeks, the young age of the patient, mainly with an acute or subacute onset, polyarthritis or acute arthralgia at onset of disease, "passive" nature of heart problems, the presence of valvulitis in association with myocarditis or pericarditis, high mobility of symptoms of carditis, correlation of biological and clinical signs of disease activity.

Rheumatoid arthritis is characterized by high quality, short duration and volatility of the lesion of mainly large and medium joints with rapid reverse development (2-3 weeks) of inflammatory changes, especially under the influence of modern anti-inflammatory therapy (for several hours or days))

Rheumatic chorea (small chorea, Sydenham chorea) develops mainly during childhood and less often in adolescence. The main clinical syndrome is choric hyperkinesis, most pronounced in the muscles of the distal extremities and the facial muscles of the face. They can be associated with muscular hypotension, coordination disorders, mental and autonomous disorders. The duration of an ENT attack in the form of small chorea is 3 to 6 months, however, the residual effects may persist for up to 1 year.

Annular (annular) erythema in recent years has been fairly rare (4-17% of cases), mainly in the pediatric population of patients with acute respiratory infections. Clinically, erythema is a pale pink annular rash of variable size, located mainly on the trunk and proximal members (but not on the face). The rashes are transient in nature, are not itchy or induction, and turn pale under pressure.

Treatment: antibacterial drugs, NSAIDs, glucocorticoids (prednisone, methylprednisolone) are used.

Prevention: Prompt diagnosis and proper treatment of streptococcal infections are of paramount importance. When invasive procedures are performed, patients with rheumatic heart disease receive prophylactic antibiotics.

Erysipelas is an infectious disease characterized by focal serous or serous-hemorrhagic inflammation of the skin, fever and intoxication.

Etiology. Most often, BSA causes erysipelas, but there are also group B, C and D streptococci. Wounds, abrasions, psoriatic, eczematous and herpetic foci can serve as entry points for infection.

Epidemiology. The disease is not officially registered, information on the incidence is based on sampling data: 140 to 220 cases per 100,000 inhabitants. People with insufficient lymphatic drainage and venous insufficiency are predisposed to a recurrent course of erysipelas. The incidence among this contingent is higher than 4,000 per 100,000. In people with chronic tonsillopharyngitis, erysipelas occurs 5 to 6 times more often.

Pathogenesis: following exposure to toxins, serous or haemorrhagic inflammation develops, complicated by purulent infiltration and necrosis.

Clinic: incubation period of several hours to 5 days. The diagnosis, as a rule, does not cause difficulties due to local characteristics (the focus of the lesion is strongly limited, hyperemic, rises above the surrounding unaffected skin, with a shiny stretched surface, painful when palpation; vesicles, bubbles often develop; regional lymphadenopathy is sometimes noted) and general (body fever, general malaise). The lower limbs are more often affected, although the hands and face may also be affected. More common in young patients aged 50 to 60 years.

Laboratory diagnosis: leukocytosis (more than 15,000), detection of antistreptolysin O, antistreptogialuronidase, antistreptokinase. It is not easy to isolate the pathogen from the focus of the lesion; it is sometimes possible to obtain a blood culture. A microbiological examination is not required for diagnosis in the classic form of erysipelas.

Choice of antimicrobial drugs: Medications of choice: for moderate infections, adults and children over 10 years old use phenoxymethylpenicillin, for severe cases, benzylpenicillin , followed by a switch to phenoxymethylpenicillin (treatment in stages). Alternative medicines: for allergies to β-lactams - macrolides, lincosamides. Duration of therapy: at least 14 days. With frequent relapses of erysipelas, benzathine benzylpenicillin is administered prophylactically once a month.

In order to prevent, it is recommended to follow the rules of personal hygiene. But due to the widespread prevalence of the pathogen in the population, these measures do not give the desired result. Great hopes are placed on the creation of a vaccine containing fragments of B-HSA M proteins which do not cross-react with tissue antigens in the human body.

A registered vaccine against GBSA infection has not yet been created. Only one drug is in the clinical trial phase (phase II). StreptAvax from ID Biomedical consists of M protein sections of the 26 most common BHCA serotypes, causing acute tonsillopharyngitis, acute respiratory infections, necrotizing fasciitis and toxic streptococcal shock syndrome.

Although the vaccine will not prevent all infections, it will significantly reduce the incidence, carriage and, therefore, the prevalence of the pathogen in the population.

Prevention of upper respiratory tract infection in people with tonsillopharyngitis should be done with a tomicide.