<i>Capnocytophaga</i> Bacteremia in Neutropenic Patients: Report of Two Cases

Dr. Salut Brunet, Departament d’Hematologia, Hospital de la Santa Creu i Sant Pau, Av. Sant Antoni Maria Claret, 167, E08025 Barcelona (Spain) Recently, several cases of blood-borne infections by Capnocytophaga species have been reported in immuno-compromised patients [1-5]. Although these microorganisms are an infrequent cause of bacteremia in neutropenic patients, we have recently observed two such infections, which occurred in our department within a short time period. The first patient was a 63-year-old male with acute nonlympho-blastic leukemia, diagnosed in October 1991, who entered complete remission after appropriate induction chemotherapy. The patient’s condition was complicated by invasive pulmonary aspergillosis (IPA) successfully treated with itraconazole. His leukemia relapsed in February 1993, and salvage chemotherapy was delivered, using a protocol which includes intermediate-dose cytarabine, intermediate-dose methotrexate, vindesine, mitoxantrone and cyclophosphamide [6]. This treatment was further complicated by severe oral mucositis (grade IV according to the WHO classification), diarrhea (grade II) and severe vomiting (grade III). During the period of severe neutropenia (absolute neutrophil count < 0.5 × 109/1), which lasted 21 days, three blood cultures drawn from a peripheral vein (n = 1) and a central venous catheter (n = 2) during an initial febrile episode were positive for Escherichia coli and Capnocytophaga sp. Empirical antibiotic treatment with meropenem was instituted, with rapid clinical improvement and no further positive blood cultures. Fever later reappeared due to reactivation of the IPA, which again resolved with oral itraconazole and recovery of the neutrophil count. In vitro susceptibility testing showed that Capnocytophaga was sensitive to penicillin, cephalosporins, imipenem, meropenem, fluo-roquinolones, chloramphenicol and tetracyclines whereas it was resistant to aminoglycosides, vancomycin and trimethoprim-sulfameth-oxazole. The second patient was a 61-year-old female who suffered from advanced-stage low-grade nonHodgkin’s lymphoma since 1980, and had received outpatient treatment with combination chemotherapy and involved-field