儿童炎症性肠病艰难梭菌感染及其易感因素分析

OBJECTIVE

To investigate the incidence rates of Clostridium difficile colonization and Clostridium difficile infection (CDI) in children with inflammatory bowel disease (IBD) and the susceptibility factors for CDI in children with IBD.

METHODS

A total of 62 children diagnosed with IBD were enrolled as the IBD group. Forty-two children who attended the hospital due to persistent or chronic diarrhea and were excluded from IBD were enrolled as the non-IBD group. The incidence rate of CDI was compared between the two groups. According to the presence or absence of CDI, the IBD group was subdivided into two groups:IBD+CDI (n=12) and non-CDI IBD (n=50), and the clinical data were collected from the two groups to analyze the susceptibility factors for CDI.

RESULTS

The IBD group had a significantly higher incidence rate of CDI[19% (12/62) vs 2% (1/42); P < 0.05] than the non-IBD group (P < 0.05). Compared with the non-CDI IBD group, the IBD+CDI group had a significantly longer disease course (P < 0.05), and a significantly higher proportion of children with fever, diarrhea, or abdominal pain (P < 0.05). The IBD+CDI group had significantly higher activity indices of pediatric Crohn's disease, C-reactive protein levels and erythrocyte sedimentation rate than the non-CDI IBD group (P < 0.05). The univariate analysis showed that compared with the non-CDI IBD group, the IBD+CDI group had a significantly higher proportion of children with moderate-to-severe disease, use of glucocorticoids, or treatment with broad-spectrum antibiotics for more than 14 days before diagnosis (P < 0.05).

CONCLUSIONS

The children with IBD have a higher incidence of CDI than those without IBD. Severe disease conditions and use of broad-spectrum antibiotics or glucocorticoids may be associated with an increased incidence of CDI in children with IBD.

[Efficacy of real-time PCR for detecting Clostridium difficile infection: comparison with enzyme-linked fluorescent spectroscopy-based approaches]

OBJECTIVE

To evaluate the diagnostic efficacy of real?time polymerase chain reaction (q?PCR) for Clostridium difficile infection (CDI) in comparison with routine culture and enzyme?linked fluorescent spectroscopy?based aprroaches.

METHODS

Stool samples were collected from suspected CDI cases in General Hospital of Guangzhou Military Command of PLA between May and December in 2016. All the samples were examined with 3 methods, namely enzyme?linked fluorescent spectroscopy for detecting Clostridium difficile toxin A/B (CDAB), detection of glutamate dehydrogenase (GDH), and q?PCR for amplification of Clostridium difficile?specific gene tpi and toxin gene (tcdA/tcdB), with the results of fecal culture as the reference for evaluating the diagnostic efficacy of the 3 methods.

RESULTS

Of the total of 70 fecal samples, 13 (18.57%) were found to be positive for Clostridium difficile, including toxin?producing strains in 6 (8.57%) samples. The sensitivity, specificity, positive predictive value, negative predictive value and diagnostic coincidence rate of q?PCR for tpi were 92.31%, 91.23%, 70.59%, 98.11% and 91.43%, respectively, which were significantly higher than those of GDH test (84.62%, 84.21%, 55.00%, 96.00%, and 84.29%, respectively; Χ²=24.881, P<0.001). The sensitivity of q?PCR for tcdA/cdB was significantly higher than that of enzyme?linked fluorescent spectroscopy for CDAB in detecting CDI (66.67% vs 33.33%; Χ²=35.918, P<0.001).

CONCLUSION

Both CDAB detection and q?PCR have a high specificity in detecting CDI, but GDH detection has a good sensitivity, and all these 3 methods have a high negative predictive value. Compared with other detection methods, amplification of tpi and tcdA/tcdB using q?PCR allows more rapid, sensitive and specific detection of CDI.