Polivkova Sylvia, Krutova Marcela, Petrlova Katarina, Benes Jiri, Nyc Otakar
Department of Infectious Diseases, 3rd Faculty of Medicine, Bulovka Teaching Hospital, Prague, Czech Republic.
Department of Medical Microbiology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic; DNA Laboratory, Department of Paediatric Neurology, Charles University, 2nd Faculty of Medicine and Motol University Hospital, Prague, Czech Republic.
Anaerobe. 2016 Aug;40:35-40. doi: 10.1016/j.anaerobe.2016.05.002. Epub 2016 May 4.
The objective of this survey was to determine the incidence of Clostridium difficile infections (CDI) at the Department of Infectious Diseases, Bulovka Hospital, and to evaluate clinical and epidemiological data on CDI patients together with a detailed molecular characterisation of C. difficile isolates. The patient outcomes were correlated to causative C. difficile PCR-ribotype.
The twelve-month study (2013) comprised patients two years of age and older with CDI. CDI severity was estimated using ESCMID criteria and ATLAS scoring. C. difficile isolates were further characterized using ribotyping, Multiple-Locus Variable Tandem-Repeats analysis (MLVA) and investigation of antibiotic-resistance determinants (gyrA, gyrB, rpoB, ermB).
A total of 619 diarrhoeal stools were investigated. Seventy-two stool samples were GDH and toxin A/B positive, and 39 samples were GDH positive only and subsequently toxigenic C. difficile was cultured. In total, 111 C. difficile isolates were characterized, of which 64 (57.7%) belonged to PCR-ribotype 176. MLVA analysis of PCR-ribotype 176 isolates revealed 11 clonal complexes. Seventy-two isolates (64.9%) showed amino acid substitution Thr82Ile in the GyrA, and sixty-two isolates (55.9%) showed amino acid substitutions Arg505Lys together with His502Asn, or Asp492Glu together with Arg505Lys in the RpoB. Twelve isolates (10.8%) were ermB positive. Severe CDI according to the ESCMID criteria was recorded in forty-two patients (37.8%), and sixteen patients (14.4%) had ATLAS score ≥ 6. Twenty-nine patients (26.1%) had recurrent CDI and twenty-four patients (21.6%) died during the study period.
A higher rate of severe CDI, recurrences and mortality in association with PCR-ribotype 176 infections were observed. The high incidence of PCR-ribotype 176 in the study, and the presence of clonal relatedness between PCR-ribotype 176 isolates, indicate its higher capacity to spread in a hospital setting, which in turn highlights the need to implement strict epidemic measures when PCR-ribotype 176 occurs.
本次调查的目的是确定布洛夫卡医院传染病科艰难梭菌感染（CDI）的发病率，并评估CDI患者的临床和流行病学数据，同时对艰难梭菌分离株进行详细的分子特征分析。将患者的预后与致病性艰难梭菌的PCR核糖体分型相关联。
这项为期12个月的研究（2013年）纳入了年龄在2岁及以上的CDI患者。使用欧洲临床微生物与感染性疾病学会（ESCMID）标准和ATLAS评分评估CDI的严重程度。使用核糖体分型、多位点可变串联重复序列分析（MLVA）以及对抗生素耐药决定因素（gyrA、gyrB、rpoB、ermB）的研究对艰难梭菌分离株进行进一步特征分析。
共调查了619份腹泻粪便样本。72份粪便样本谷氨酸脱氢酶（GDH）和毒素A/B呈阳性，39份样本仅GDH呈阳性，随后培养出产毒艰难梭菌。总共对111株艰难梭菌分离株进行了特征分析，其中64株（57.7%）属于PCR核糖体分型176。对PCR核糖体分型176分离株的MLVA分析揭示了11个克隆复合体。72株分离株（64.9%）在GyrA中显示苏氨酸82位异亮氨酸氨基酸替代，62株分离株（55.9%）在RpoB中显示精氨酸505位赖氨酸氨基酸替代以及组氨酸502位天冬酰胺，或天冬氨酸492位谷氨酸与精氨酸505位赖氨酸同时出现。12株分离株（10.8%）ermB呈阳性。根据ESCMID标准，42例患者（37.8%）记录为严重CDI，16例患者（14.4%）的ATLAS评分≥6。29例患者（26.1%）发生复发性CDI，24例患者（21.6%）在研究期间死亡。
观察到与PCR核糖体分型176感染相关的严重CDI、复发和死亡率较高。本研究中PCR核糖体分型176的高发病率以及PCR核糖体分型176分离株之间存在克隆相关性，表明其在医院环境中具有较高的传播能力，这反过来凸显了在出现PCR核糖体分型176时实施严格防疫措施的必要性。
