Correlation of the detection of Clostridium difficile toxins in stools and presence of the clostridia in tissues of children
ABSTRACT Clostridium difficile toxin is frequently found in the stool of children; however, pseudomembranous colitis is rare. Studying the usefulness of Clostridium difficile toxin assays in pediatrics is required. We performed a correlation between presence of Clostridium difficile toxin in stool and evidence of Clostridium difficile in gastrointestinal pediatric tissue samples using immunohistochemistry (with a pan-clostridial antibody) and polymerase chain reaction (with primers for toxin genes). We studied 11 patients with a median age of 8 years (range, 4 weeks to 17 years); 4 (36%) were female. The median time between detection of Clostridium difficile toxin in stool and obtaining tissue was 3 days. Ten patients survived. Endoscopy was performed in 8 survivors and showed normal mucosa in 2, pseudomembranes in 2, erythema and friability in 1, aphthae in 1, increased mucous production in 1, and colitis in 1. Two survivors underwent laparotomy for either obstruction or resection of necrotic bowel. Histopathologic studies in these 10 surviving patients showed necrosis in 2 samples, granulomatous inflammation in 1, moderate colitis in 1, and mild to minimal pathology in 7. There was no antigenic or molecular evidence of clostridia in the tissue of these patients. Histopathologic evidence of pseudomembranes and immunohistochemical evidence of clostridia were present in postmortem intestinal tissues of the only patient that died. Our findings indicate that Clostridium difficile toxin in stool does not correlate with the presence of clostridia and may not contribute to pathology in intestinal tissues of children. Clostridial antigens were only observed with histopathologic evidence of pseudomembranes.
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