Leukocytosis as a harbinger and surrogate marker of Clostridium difficile infection in hospitalized patients with diarrhea

OBJECTIVES: Clostridium difficile is the etiological agent of antibiotic-as sociated diarrhea and pseudomembranous colitis and is a leading cause of no socomial diarrhea. The objective of the study was to examine if leukocytosi s could be a harbinger and surrogate marker of C. difficile infection in ho spitalized patients. METHODS: We retrospectively examined the medical records of 70 hospitalized patients who presented with diarrhea of variable severity and who underwen t stool examination for enteric pathogens, including C. difficile. We speci fically recorded the white blood cell count and the pattern and severity of leukocytosis in two groups of patients-those who were C. difficile-positiv e and those who were negative. RESULTS: Leukocytosis was common in C. difficile-positive patients, compare d to in C. difficile-negative patients (mean 15,800/mm(3) vs 7700/mm(3), p < 0.01). Review of the 35 C. difficile-positive patients revealed three pat terns: Pattern A) sudden WBC increase coinciding with the onset of symptoms suggestive of C. difficile; Pattern B) unexplained leukocytosis preceding the appearance of C. difficile-related diarrhea and serving as a harbinger of the infection; and Pattern C) worsening of pre-existing leukocytosis as a surrogate marker of C. difficile infection. Treatment with metronidazole led to amelioration of symptoms and normalization of the leukocyte count in all cases. CONCLUSIONS: Infection with C. difficile should be considered in the differ ential diagnosis of sudden onset of leukocytosis in hospitalized patients p reviously or concurrently treated with antibiotics. Doing so may obviate th e need for expensive and time-consuming tests fur other etiologies. (C) 200 0 by Am. Cell. of Gastroenterology).