The role of the gut microbiota in triggering autism is a rapidly emerging field of research. Gut microbiota have been incriminated because autistic children often have gastrointestinal symptoms. Pathogenic gut bacteria in children with autism spectrum disorders (ASD) have been reported. The present study aimed to assess Clostridium difficile in the stool of children with ASD and its relation to gastrointestinal (GI) comorbidities, autism severity, and sensory impairment. The study included 58 ASD patients, 45 of their neurotypical siblings, and 45 unrelated controls. Childhood Autism Rating Scale (CARS) was used to assess the severity of autism. Sensory problems were evaluated using the Short Sensory Profile (SSP). GI symptoms were assessed with a modified six-item GI Severity Index (6-GSI) questionnaire. Quantitative real-time PCR was done for the detection and quantitation of C. difficile and its toxins A and B. C. difficile was detected in 25.9%, 40%, and 15.6% of ASD cases, siblings, and unrelated control respectively. Regarding toxin A and B production, 73.3%, 77.8%, and 71.4% of C. difficile in positive ASD, siblings, and unrelated control cases respectively were toxigenic. There was no statistically significant difference between the three groups as regards C. difficile qualitative, quantitative, and toxin production results. In conclusion,C. difficile is not specifically prevalent in the gut of children with ASD. Although most of the strains are toxigenic, there were no GI symptoms in the control groups and no statistically significant association with GI Severity Index in autistic cases. Gastrointestinal dysfunction and sensory impairment are common comorbidities in ASD.

肠道微生物群在引发自闭症中的作用是一个迅速兴起的研究领域。肠道微生物群被认为是有罪的，因为自闭症儿童经常有胃肠道症状。已经报道了自闭症谱系障碍 (ASD) 儿童体内的致病性肠道细菌。本研究旨在评估艰难梭菌在 ASD 儿童的粪便中及其与胃肠 (GI) 合并症、自闭症严重程度和感觉障碍的关系。该研究包括 58 名 ASD 患者、45 名他们的神经典型兄弟姐妹和 45 名不相关的对照。儿童自闭症评定量表（CARS）用于评估自闭症的严重程度。使用短感官概况 (SSP) 评估感官问题。GI 症状通过改进的六项 GI 严重程度指数 (6-GSI) 问卷进行评估。对艰难梭菌及其毒素进行了定量实时 PCR 检测和定量。在 ASD 病例、兄弟姐妹和无关对照中分别检测到 25.9%、40% 和 15.6% 的艰难梭菌。关于毒素 A 和 B 的产生，艰难梭菌分别为 73.3%、77.8% 和 71.4%在阳性 ASD 中，兄弟姐妹和不相关的对照病例分别是有毒的。在艰难梭菌定性、定量和毒素产生结果方面，三组之间没有统计学上的显着差异。总之，艰难梭菌在 ASD 儿童的肠道中并不特别普遍。尽管大多数菌株是有毒的，但对照组中没有胃肠道症状，并且与自闭症病例中的胃肠道严重程度指数没有统计学上的显着关联。胃肠功能障碍和感觉障碍是 ASD 常见的合并症。