Carriage and colonization of C-difficile in preterm neonates: A longitudinal prospective study
Carriage and colonization of C-difficile in preterm neonates: A longitudinal prospective study
复制标题
DOI：
10.1371/journal.pone.0212568
复制
发表时间：
2019-02-20
期刊：
影响因子：
3.7
通讯作者：
Aires, Julio
中科院分区：
文献类型：
--
作者：
Ferraris, Laurent;Couturier, Jeanne;Aires, Julio
早产儿（PN）存在多个高频率和高水平C定植的危险因素。很难，但关于这一特定儿科人群的数据缺失。在这里，我们调查了PN C。difficile carriage and colonization dynamics，analysed impact of perinatal determinants on colonization，and characterized the isolates. MethodsA one year longitudinal monocentric prospective cohort study was performed on 121 PN. C.采用PCR（tpi管家基因、tcdA和tcdB以及二元毒素基因）、毛细管凝胶电泳PCR-核糖体分型和多位点可变数目串联重复序列分析（MLVA）对从选择性培养基上的粪便样品中分离的艰难梭菌菌株进行鉴定和表征。艰难梭菌培养阳性，C.艰难梭菌定植随时间显著降低（P =.027）。住院期间，C.艰难梭菌定殖频率增加至61%，其中95%的菌株属于两种非同源性PCR-核糖体型（RT）FR 082（35%）和032（60%）。出院后，如果观察到RT的多样性较高，则RT FR 082和032仍占主导地位（分别为40%和28%）。MLVA在每个FR 082和032 RT内显示克隆关系。共分离出10株（5%）产酶菌株，除1株tcdA（-）/tcdB（+）外，其余均为tcdA（+）/tcdB（+），且均为住院后获得。在1周时，发现与C频率较高相关的唯一因素。艰难梭菌定植与孕龄、出生体重有关（P = 0.006、P = 0.016）。PN中的艰难梭菌定植遵循特定模式。C.艰难梭菌定植在出生后迅速发生，具有低多样性的非致突变性RT。住院后，非致突变性RT的多样性增加。住院后观察到散在携带致病菌株。
BackgroundPremature neonates (PN) present multiple risk factors for high frequencies and high levels of colonization by C. difficile, yet data is missing about this specific pediatric population. Here, we investigated PN C. difficile carriage and colonization dynamics, analyzed the impact of perinatal determinants on colonization, and characterized the isolates.MethodsA one year longitudinal monocentric prospective cohort study was performed on 121 PN. C. difficile strains isolated from fecal samples on selective medium were identified and characterized by PCR (tpi housekeeping gene; tcdA and tcdB, and binary toxin genes), capillary gel-based electrophoresis PCR-ribotyping, and Multi-Locus Variable-number tandem repeat Analysis (MLVA).ResultsOf the 379 samples analyzed, 199 (52%) were C. difficile culture positive with the mean levels of C. difficile colonization decreasing significantly (P = .027) over time. During hospitalization, C. difficile colonization frequency increased up to 61% with 95% of the strains belonging to both non-toxigenic PCR-ribotypes (RTs) FR082 (35%) and 032 (60%). After hospital discharge, if a higher diversity in RTs was observed, RTs FR082 and 032 remained predominant (respectively 40% and 28%). MLVA showed clonal relationship within each FR082 and 032 RTs. Ten toxigenic strains (5%) were isolated, all tcdA(+)/tcdB(+) except for one tcdA(-)/tcdB(+), and all being acquired after hospitalization. At 1 week, the only factors found to be linked with a higher frequency of C. difficile colonization were a higher gestational age (P = 0.006) and a higher birth weight (P = 0.016).ConclusionThe dynamics of C. difficile colonization in PN followed a specific pattern. C. difficile colonization rapidly occurred after birth with a low diversity of non-toxigenic RTs. After hospitalization, non-toxigenic RTs diversity increased. Sporadic carriage of toxigenic strains was observed after hospitalization.