Capnocytophaga bacteremia: clinical features of patients and antimicrobial susceptibility of isolates.

Capnocytophaga has been recognized as an opportunistic pathogen causing systemic infections in immunocompromised individuals with granulocytopenia and oral ulceration. Treatment of Capnocytophaga infection is often empiric. We retrospectively analyzed the clinical features of all patients with Capnocytophaga bacteremia seen at the National Taiwan University Hospital between January 1981 and December 1996 and the antimicrobial susceptibility of the isolates recovered from these patients. All the patients had underlying diseases, namely neoplastic disease (9 patients), hyperthyroidism (1), and bronchiectasis and tetralogy of Fallot (1). The clinical features of these patients were primary bacteremia (10) and pneumonia (1). Nine patients had nosocomial bacteremia and 10 patients had monomicrobial bacteremia. None had septic shock. All the patients responded well to appropriate antimicrobial therapy and survived. All isolates were susceptible to amoxicillin-clavulanate, imipenem, ciprofloxacin, erythromycin, clindamycin, tetracycline, and chloramphenicol but resistant to aminoglycosides and sulfamethoxazole-trimethoprim. The susceptibilities to penicillin, ampicillin, piperacillin, cephalosporins, and aztreonam were variable. Capnocytophaga bacteremia should be included in the differential diagnosis of febrile neutropenia in immunocompromised patients, especially in the presence of oral mucositis and ulceration.