Clostridium tertium septicemia in patients with neutropenia.

Eighteen adult patients with hematologic malignancy developed bacteremia due to Clostridium tertium while neutropenic. Fifteen had accompanying abdominal pain, colonic bleeding, or diarrhea, and three had perianal cellulitis. Fourteen recovered with antibiotic therapy alone; no patient was treated by surgery. C. tertium is an unusual Clostridium because it is resistant to many beta-lactam antibiotics and to metronidazole but is susceptible to vancomycin, trimethoprim-sulfamethoxazole, and ciprofloxacin. It is possible that use of third-generation cephalosporins (cefotaxime, ceftizoxime, ceftazidime) for treating febrile episodes in the absence of any selective intestinal decontamination with trimethoprim-sulfamethoxazole or ciprofloxacin may have resulted in selection for C. tertium in our patients.