Department of Gastroenterology and Hepatology, The Jikei University Kashiwa Hospital, Kashiwa 277-8567, Chiba, Japan.
Jpn J Infect Dis. 2013;66(2):109-14. doi: 10.7883/yoken.66.109.
Fusobacterium varium is an elusive pathogenic factor in ulcerative colitis (UC); conventional methods of fecal culture rarely recover F. varium. We have developed a nested culture method to recover Fusobacterium and we used it to investigate whether F. varium could be isolated from UC patients. We enrolled 50 consecutive patients in this study; 26 received combination antibiotic therapy that included amoxicillin, tetracycline, and metronidazole (ATM) for 2 weeks and were thus assigned to the ATM group, and the remaining 24 were assigned to the non-ATM group and did not receive any antibiotics. Stool samples were added to 10 ml of GAM broth that contained neomycin and crystal violet. The samples were vortexed and incubated under anaerobic conditions. The preincubated broth was streaked onto a Fusobacterium-selective agar plate and then incubated under anaerobic conditions. The species of the colonies isolated were identified using the Vitek Automated system and PCR analysis. We recoverd F. varium from 7 of the 24 non-ATM patients (29.2%) and none from the ATM patients (0%) (P = 0.0035). All of the F. varium isolates were susceptible to ATM. This study suggests that the recovery of F. varium is related to UC, which aligns with results from previous studies that used mucosal culture, immunostaining, real-time PCR, and serological studies.
脆弱拟杆菌是溃疡性结肠炎（UC）中一种难以捉摸的致病因素；常规粪便培养方法很少能恢复脆弱拟杆菌。我们开发了一种嵌套培养方法来回收梭杆菌，并用它来研究是否可以从 UC 患者中分离出脆弱拟杆菌。我们招募了 50 名连续患者进行这项研究；26 名患者接受了包括阿莫西林、四环素和甲硝唑（ATM）在内的联合抗生素治疗 2 周，因此被分配到 ATM 组，其余 24 名患者被分配到非-ATM 组，没有接受任何抗生素治疗。粪便样本被添加到含有新霉素和结晶紫的 10ml GAM 肉汤中。将样品涡旋并在厌氧条件下孵育。将预孵育的肉汤划线接种到脆弱拟杆菌选择性琼脂平板上，然后在厌氧条件下孵育。使用 Vitek 自动化系统和 PCR 分析鉴定分离出的菌落的种类。我们从 24 名非-ATM 患者中的 7 名（29.2%）中恢复了脆弱拟杆菌，而从 ATM 患者中没有恢复（0%）（P=0.0035）。所有脆弱拟杆菌分离株均对 ATM 敏感。这项研究表明，脆弱拟杆菌的恢复与 UC 有关，这与之前使用黏膜培养、免疫染色、实时 PCR 和血清学研究的结果一致。
