Prevalence of Group A b-Hemolytic Streptococcus Among Children with Tonsillopharyngitis in Kyrgyzstan: The Difficulty of Diagnostics and Therapy

Rheumatic fever (RF) is well known disease as a result of frequent complication of the group A- b hemolytic streptococcal (GABHS) tonsillopharyngitis, have noticeably grown for the last 15 years among young generation in the Kyrgyz Republic. It is important to hold a study about the prevalence of RF and GABHS and their susceptibility to antibiotics in the Kyrgyz Republic.

We have studied 200 children with chronic tonsillopharyngitis at the National Center of Pediatrics and Child Surgery in Bishkek (the Kyrgyz Republic) from August till September 2008. 188 (48 out of them are with RF) out of total 200 children are Kyrgyz and 12 are Russian (2 out of them are with RF). 111 out of total are female (34 out of them are with RF) and 89 are male (17 out of them are with RF). The average age of the subjects is 10.9±6.0 (from 3 to 17 years old). The presence of GABHS was assessed using two ways: by the rapid antigen detection test (RADT) for outcrop of streptococcus antigen in smear from mucosal surface of tonsils, and by bacterial culture analysis (BA). RADT was used to determine its specificity and sensitivity in order to recommend practitioners its further wide use. Furthermore, the discovered culture of GABHS have been investigated on susceptibility to antibiotics by disc-diffusion method.

GABHS antigen was positive in 72 (36.0 %) subjects from RADT and in 80 (40.0%) subjects from BA out of 200 total subjects. In the patients with RF (n=51), GABHS was positive in 18 (35.2%) subjects by RADT and in 24 (47.0%) subjects by BA. In the subjects without RF (n=149), GABHS was positive in 54 (36.2%) subjects by RADT and in 56 (37.5%) by BA. Among 80 GABHS positive results sensitive to antibiotics were: to penicillin only 10 (12.5%), to ampicillin-29 (36.2%), to amoxicillin-36 (45.0%), to ceftriaxon - 31 (38.7%), to roxithromycin - 21 (26.2%), to erythromycin- 19 (23.7%). It is noted that 21 (26.2%) GABHS positive results were absolutely resistant for all these tested antibiotics. RADT showed that its specificity is 85% as well as its sensitivity is equal to 67.5%.

In this study the sensitivity of RADT was low; therefore, the negative results of RADT don’t exclude presence of GABHS. High prevalence of GABHS antigen demonstrates not only in patients with RF, but also among healthy children (without RF) of the Kyrgyz Republic. The high prevalence of GABHS at children with RF (47.0%), probably, presents a low sensitivity to antibiotics and irregular secondary prophylaxis. Significant presence of GABHS among healthy children (37.5%) requires improvement of primary prevention to prevent further spread of RF and Rheumatic Heart Disease (RHD) in the country.