Kato H, Kato N, Watanabe K, Ueno K, Sakata Y, Fujita K
Institute of Anaerobic Bacteriology, Gifu University, School of Medicine, 40 Tsukasa-machi, Gifu 500, Japan.
Curr Microbiol. 1996 Oct;33(4):220-3. doi: 10.1007/s002849900103.
Immunoblotting and pulsed-field gel electrophoresis of Clostridium difficile isolates were employed to differentiate reinfection by a newly acquired strain from relapse by an original strain in a 10-year-old patient with four episodes of C. difficile-associated colitis. Immunoblot typing demonstrated subserogroup K-1 of serogroup K for the first and second organisms, subserogroup A-1 of serogroup A for the third organism, and subserogroup G-4 of serogroup G for the fourth organism. PFGE analysis revealed consistent results with immunoblot analysis except that the strains from the fourth episode, whose DNA constantly degraded, were nontypable by this method. Five separate isolates of C. difficile from a specimen of each episode showed identical PFGE patterns, indicating that infections of multiple strains probably did not occur in this patient. These typing results suggested that the second episode after a 17-day course of vancomycin therapy represented a relapse by the strain causing the first episode, and that the third and fourth episodes after tapering vancomycin therapy were reinfections by other strains. Both immunoblot and PFGE typing systems are promising tools for analyzing recurrence of C. difficile infection.
对艰难梭菌分离株进行免疫印迹和脉冲场凝胶电泳，以区分一名10岁患有4次艰难梭菌相关性结肠炎的患者是新获得菌株导致的再感染还是原始菌株导致的复发。免疫印迹分型显示，第一株和第二株菌属于血清型K的K-1亚群，第三株菌属于血清型A的A-1亚群，第四株菌属于血清型G的G-4亚群。脉冲场凝胶电泳（PFGE）分析结果与免疫印迹分析一致，只是第四株菌的DNA持续降解，无法用该方法进行分型。从每一次发作的标本中分离出的5株独立的艰难梭菌显示出相同的PFGE图谱，表明该患者可能未发生多种菌株感染。这些分型结果表明，在万古霉素治疗17天疗程后的第二次发作是由导致第一次发作的菌株复发引起的，而在万古霉素治疗逐渐减量后的第三次和第四次发作是由其他菌株导致的再感染。免疫印迹和PFGE分型系统都是分析艰难梭菌感染复发情况的有前景的工具。
