123例腹泻患儿粪便中艰难梭菌毒素基因特征及感染危险因素分析

探讨腹泻患儿粪便中艰难梭菌毒素基因特征, 并分析产毒艰难梭菌感染的危险因素。

采集2019年1月至2021年3月嘉兴市第二医院儿科收治的腹泻患儿的粪便标本共123份, 其中社区获得性腹泻患儿60例, 医院获得性腹泻患儿63例。标本进行厌氧培养, 采用实时荧光PCR鉴定艰难梭菌tpi基因, 并检测tcd A、tcd B毒素基因。收集患儿临床资料, 采用Logistic回归分析产毒艰难梭菌感染的危险因素。

123例粪便标本共检出艰难梭菌tpi基因阳性35例(28.46%), 毒素基因中tcd A⁺ B⁺为19例(15.45%), tcd A⁺B^-为3例(2.44%), tcd A^-B⁺为2例(1.63%), tcd A^-B^-为11例(8.94%)。社区获得性腹泻患儿中tcd A/B产毒艰难梭菌感染率为28.33%, 高于医院获得性腹泻患儿的11.11%(P < 0.05)。产毒艰难梭菌感染腹泻患儿与非产毒艰难梭菌感染腹泻患儿的性别、年龄、居住地、是否早产、有无先天性疾病、既往有无胃肠道手术、抗生素应用种类、近1个月内有无机械通气、临床症状、血液白细胞计数、血红蛋白、粪便白细胞计数、血清C反应蛋白、血清白细胞介素-6、血清白蛋白、血肌酐、血清总胆红素水平比较差异无统计学意义(均P > 0.05)。产毒艰难梭菌感染腹泻患儿中的非母乳喂养、近1个月内抗生素用药史、抗生素持续用药时间 > 7 d、近1个月内糖皮质激素用药史、近1个月内抑酸药用药史、近1个月内肠内营养者的比例显著高于非产毒艰难梭菌感染腹泻患儿(均P < 0.05)。非母乳喂养(OR=2.433)、近1个月内抗生素用药史(OR=3.040)、近1个月内肠内营养(OR=2.330)是腹泻患儿产毒艰难梭菌感染的独立危险因素(均P < 0.05)。

嘉兴地区儿童艰难梭菌毒素基因主要为tcd A/B基因, 患儿以社区获得性腹泻为主, 非母乳喂养、抗生素用药史、肠内营养的儿童更容易感染艰难梭菌。

Toxin gene characteristics of Clostridium difficile in stool specimens from 123 children with diarrhea and the risk factors

ObjectiveTo investigate the toxin gene characteristics of Clostridium difficile in stool of children with diarrhea, and analyze the risk factors of toxigenic Clostridium difficile infection.MethodsA total of 123 stool specimens were collected from children with diarrhea admitted to the Pediatric Department of our hospital between January 2019 and March 2021, including 60 children with community-acquired diarrhea and 63 with hospital-acquired diarrhea. The specimens were collected for anaerobic culturing. Real-time fluorescent PCR method was used to identify tpi gene of Clostridium difficile, and tcd A and tcd B toxin genes were detected. The clinical data of the children were collected, and logistic regression analysis was performed to screen the risk factors of toxigenic Clostridium difficile infection.ResultsOf the 123 stool specimens, 35(28.46%) were positive for tpi gene of Clostridium difficile. Toxin gene characteristics were as follows: tcd A+B+ in 19 cases(15.45%), tcd A+B- in 3 cases(2.44%), tcd A-B+ in 2 cases(1.63%), and tcd A-B- in 11 cases(8.94%). The infection rate of tcd A/B toxigenic Clostridium difficile in children with community-acquired diarrhea was 28.33%, higher than the 11.11% in children with hospital-acquired diarrhea(P < 0.05). There were no significant differences between diarrhea children with toxigenic Clostridium difficile infection and those with nontoxigenic Clostridium difficile infection in terms of gender, age, place of residence, premature birth, congenital diseases, previous history of gastrointestinal surgery, type of antibiotics used, mechanical ventilation in the past month, clinical symptoms, white blood cell count, hemoglobin, stool white blood cell count, serum C-reactive protein, serum interleukin-6, serum albumin, serum creatinine, and serum total bilirubin levels(all P > 0.05). The proportions of non-breastfeeding, history of antibiotic use in the past month, time of using antibiotics > 7 d, history of glucocorticoid use in the past month, history of acid inhibitor use in the past month and enteral nutrition in the past month in diarrhea children with toxigenic Clostridium difficile infection were significantly higher than those in children with nontoxigenic Clostridium difficile infection(all P < 0.05). Non-breastfeeding(OR=2.433), history of antibiotic use in the past month(OR=3.040), and enteral nutrition in the past month(OR=2.330) were independent risk factors for toxigenic Clostridium difficile infection in children with diarrhea(all P < 0.05).Conclusiontcd A/B toxin genes of Clostridium difficile are dominant in children with diarrhea in Jiaxing area, and community-acquired diarrhea is more common. Children who are not breastfed, have history of antibiotic use and enteral nutrition are more prone to Clostridium difficile infection.