Nosocomial Infection Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Microbiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
BMC Infect Dis. 2019 Apr 30;19(1):361. doi: 10.1186/s12879-019-3965-8.
Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that is widely identified worldwide. This study aimed to investigate the phenotypic characterization and molecular typing of Clostridium difficile isolates among patients with UC at an inflammatory bowel disease clinic in Iran.
In this cross-sectional study, conducted from April 2015 to December 2015, 85 UC patients were assessed for C.difficile infection (CDI). C. difficile isolates were characterized based on their toxin profile and antimicrobial resistance pattern. Multi-locus sequence typing analysis (MLST) and PCR ribotyping were performed to define the genetic relationships between different lineages of toxigenic strains.
The prevalence of C. difficile isolates was 31.8% (27/85) in patients, of those 15 patients (17.6%) had CDI. Three different sequence types (STs) identified based on MLST among the toxigenic isolates, that is ST54 (33.3%), ST2 (53.3%), and ST37 (13.6%). C. difficile strains were divided into four different PCR-ribotypes (012, 014, 017 and IR1). The most common ribotype was 014 accounting for 48.3% (7/15) of all strains. The strains isolated during the first episode and recurrence of CDI usually belonged to PCR ribotype 014 (ST2). A high rate of CDI recurrence (14.1%, 12/85) experienced in UC patients. Colonization of the gastrointestinal tract with non-toxigenic C. difficile strains was frequent among patients with mild disease. All C. difficile isolates were susceptible to metronidazole, and vancomycin, 86 and 67% of isolates were resistant to clindamycin and erythromycin respectively. There was no correlation between the toxin type and antibiotic resistance (p > 0.05).
Overall CDI is rather prevalent in UC patients. All patients with CDI experienced moderate to severe disease and exposed to different antimicrobial and anti-inflammatory agents. Close monitoring and appropriate management including early detection and fast treatment of CDI will improve UC outcomes.
溃疡性结肠炎（UC）是一种在全球范围内广泛存在的炎症性肠病（IBD）。本研究旨在探讨伊朗炎症性肠病诊所中 UC 患者中艰难梭菌分离株的表型特征和分子分型。
在这项横断面研究中，于 2015 年 4 月至 2015 年 12 月对 85 例 UC 患者进行了艰难梭菌感染（CDI）评估。根据毒素谱和抗生素耐药模式对艰难梭菌分离株进行特征描述。进行多位点序列分型分析（MLST）和 PCR 核糖体分型，以定义产毒株不同谱系之间的遗传关系。
85 例患者中艰难梭菌分离株的患病率为 31.8%（27/85），其中 15 例（17.6%）患有 CDI。基于 MLST 从产毒分离株中鉴定出 3 种不同的序列型（ST），即 ST54（33.3%）、ST2（53.3%）和 ST37（13.6%）。艰难梭菌菌株分为 4 种不同的 PCR-核糖体型（012、014、017 和 IR1）。最常见的核糖体型是 014，占所有菌株的 48.3%（7/15）。首次发作和 CDI 复发时分离的菌株通常属于 PCR 核糖体型 014（ST2）。UC 患者中 CDI 复发率较高（14.1%，12/85）。胃肠道定植非产毒艰难梭菌菌株在轻度疾病患者中较为常见。所有艰难梭菌分离株均对甲硝唑敏感，86%和 67%的分离株分别对克林霉素和红霉素耐药。毒素型与抗生素耐药性之间无相关性（p>0.05）。
总体而言，UC 患者中 CDI 较为普遍。所有 CDI 患者均患有中重度疾病，并接触过不同的抗生素和抗炎药物。密切监测和适当管理，包括早期发现和快速治疗 CDI，将改善 UC 结局。
