Microbiological Study Of Clostridium Difficile Infection In Hospitalized Patients

Purpose: C. difficile infection (CDI) is associated with an array of clinical manifestations, ranging from asymptomatic colonization to mild diarrhea or more severe pseudomembranous colitis that may progress to toxic megacolon, intestinal perforation, sepsis and death. The aim of this study was to determine the incidence of C. difficile infection among children with hospital acquired diarrhea and to evaluate different microbiological methods for diagnosing CDI. Methods & Materials: The study was conducted among children with healthcare-associated diarrhea who were inpatients at a university hospital in Cairo between May 2013 and June 2015. CDI was defined as the presence of diarrhea (three or more stools in 24 h), a stool culture positive for toxigenic C. difficile (TC) and a positive stool toxin assay (Enzyme Immunoassay EIA; or Cytotoxicity assay CTA). Healthcare-associated diarrhea was defined as symptom onset >48 h after admission to hospital. All stool specimens (465) were processed by TC, only specimens showed positive results were subjected to other methods (CTA and EIA). Results: C. difficile was isolated in 51 of 465 (11%) stool specimens. Of the 51 C. difficile isolates, 51 (100%) gave positive result by TC, 44 (86.3%) gave positive result by EIA and 50 (98%) gave positive result by CTA. All patients in this study were under antibiotic therapy. Antimicrobial classes with broad-spectrum activity, including 4th generation cephalosporins (P = 0.001), aminoglycosides (P < 0.001), levofloxacin (P = 0.032), meropenems (P = 0.012) and vancomycin (P = 0.002), were associated with CDI. The majority of patients received aggressive antibiotic therapy with more than one antibiotic during the hospitalization period (P < 0.001). Conclusion: This study showed that antibiotic therapy remains the main risk factor for developing CDI in children. We found that the toxin EIA test is not suitable as a stand-alone test because of low sensitivity. CTA was found to be better correlated to clinical outcome compared with the TC method. We propose the use of TC as a gold standard for detection of toxigenic C. difficile, as it provides high sensitivity and specificity.