The resistance level of Streptococcus pyogenes to erythromycin in Kraljevo during 2011

Objective. Streptococcus pyogenes is one of the most common and most severe cause of bacterial infections of the throat in humans. It requires antibiotic therapy, usually penicillin preparations. In case of need of using other antibiotics (due to allergies), macrolides (erythromycin) are most commonly used. The sensitivity of these bacteria to erythromycin is high, but the resistance to it is growing. Aim of the study was determination of level of resistance of Streptococcus pyogenes to erythromycin in Kraljevo, during 2011. Methods. The database of the department of clinical microbiology of Public Health Institute in Kraljevo was used as a source of data collected in 2011. Data were analyzed using the method of descriptive statistics, and computer program as tool for this analysis. Results. During 2011, on the territory of the city of Kraljevo 5040 samples of throat swab taken from adults were analyzed. In 4885 samples physiological flora was found (96.9%), and 155 samples were with pathological findings. In 46 patients streptococcus pyogenes was isolated (that is 0.9% of all surveyed, and 29.7% of those where some type of a bacterial infection was isolated). In 40 findings with streptococcus pyogenes the sensitivity to erythromycin was examined, sensitivity existed in 28 cases, intermediate result was obtained in 6 cases, and resistance to erythromycin was discovered in 6 cases (15%) also. Conclusion. Erythromycin is effective in the therapy of infections caused by β-hemolytic streptococcus of group A. It is one of the primary choices in the therapy of these infections when it is necessary to apply some other antibiotic instead of penicillin. Uncontrolled usage of macrolides has caused significant increase of resistance of streptococcus pyogenes to it, so its restrictive and targeted application in treatment should be an imperative in the future.