영아에서의 침습 B군 사슬알균 감염증 및 혈청형 분석: 2개 대학병원 연구

목적: 침습 B군 사슬알균(group B streptococcus [GBS]) 감염증에서 분리된 균의 혈청형과 임상적 특징의 관계를 분석하고자 하였다. 방법: 가천대 길병원과 삼성서울병원에 입원한 GBS 감염 환자 데이터를 후향적으로 수집하고 슬라이드 응집법으로 혈청형을 정하였다. 결과: 총 37명 중 만삭아 22명, 미숙아 15명이었고, 조발형 15명(40.5%), 지발형 19명(51.4%), 늦은 지발형 3명(8.1%)이었다. 조발형이 미숙아에서 더 많이 발생하였다(P =0.17). 임상 양상은 균혈증(70.3%)이 가장 흔했고, 수막염, 화농관절염 순이었다. 혈청형 분석이 가능했던 24 균주 중 III형이 가장 흔했고 (41.7%), V (16.7%), Ia, Ib, II (각각 12.5%), non-typeable (4.2%)였다. III형은 만삭아에서 더 많았던 반면, V형은 미숙아에서 더 흔했다. 페니실린 내성균은 없었고 에리트로마이신과 클린다마이신 내성은 각각 64.9%였다. 결론: GBS는 미숙아와 만삭아에게 모두 중요한 병원체이며 혈청형 분포에서도 미숙아와 만삭아 간에 차이가 있을 수 있다. 조발형 질환의 발생을 과소평가하지 않고 적절한 예방 대책을 마련하기 위해 미숙아를 포함한 GBS 질환의 전국적인 역학을 감시하는 것이 필요하다. Purpose: This study was aimed at analyzing the serotypes of group B streptococcus (GBS) isolated from Korean infants with invasive disease and evaluating their association with disease manifestation. Methods: Data were retrospectively collected from invasive GBS infections at Gachon University Gil Medical Center from January 2006 to June 2012 and at Samsung Medical Center from April 2010 to November 2012. Serotypes were determined by slide agglutination test. Results: A total of 37 cases were identified, which included 22 full-term infants and 15 preterm infants. Fifteen cases (40.5%) were early-onset, 19 (51.4%) was late-onset, and three (8.1%) was very late-onset. Early-onset diseases among preterm infants were higher than those among full-term infants (60.0% [9/15] vs. 27.3% [6/22], P =0.17). The most common manifestation was bacteremia (70.3%), followed by meningitis and septic arthritis. Among 24 isolates retrievable for serotyping, serotype III (41.7%) was most common, followed by V (16.7%), Ia, Ib, and II (12.5%, respectively), and non-typeable (4.2%). Serotype III was more common in isolates from full-term infants (10/22) than from preterm infants (0/15), whereas serotype V was more common in isolates from preterm infants (4/15) than from full-term infants (0/22) (P =0.002). No penicillin-resistant strain was detected, and resistance to erythromycin and clindamycin were both 64.9%. Conclusions: GBS is an important pathogen in both preterm and full-term infants, and serotype distribution of GBS causing invasive diseases can differ between preterm and full-term infants. It is necessary to monitor the nationwide epidemiology of GBS diseases, including in preterm infants, in order to prepare preventive measures without underestimating early-onset diseases.