INFECTION PREVENTION IN SEVERELY MYELOSUPPRESSED PATIENTS - A COMPARISON BETWEEN CIPROFLOXACIN AND A REGIMEN OF SELECTIVE ANTIBIOTIC MODULATION OF THE INTESTINAL FLORA

Purpose: To study whether oral ciprofloxacin would be as effective in preventing bacterial infections in severely myelosuppressed patients a s selective antibiotic modulation of the gut flora with neomycin/polym yxin B sulfate/nalidixic acid (NPN). Patients and methods: One hundred and five patients undergoing allogeneic or autologous bone marrow tra nsplant, or induction therapy for acute leukemia in 1988 and 1989 were studied. Patients were stratified according to the type of therapy, a nd randomized in a ratio of 2:1 to either oral ciprofloxacin 500 mg BI D, or a combination of oral neomycin 250 mg QID, polymyxin-B 100 mg QI D, and oral nalidixic acid 1,000 mg BID. Treatment began on admission and continued until the absolute granulocyte count was greater than 50 0/mm(3) for 3 consecutive days. Results: The 96 evaluable patients wer e evenly distributed over the 3 treatment groups; 63 patients received ciprofloxacin and 33 received NPN. Fever developed in 92% of patients on ciprofloxacin and in 97% of patients on NPN (P = 0.66), 6.6 +/- 5. 8 and 7.2 +/- 5.3 days from the start of prophylaxis, respectively. Tw enty=five patients on ciprofloxacin developed 29 microbiologically doc umented infections, fewer than the 26 infections in the 22 patients on NPN (P = 0.02). Patients on ciprofloxacin had fewer bacteremias (33%) than did the NPN patients (55%) (P = 0.05). Gram-negative bacteremias were very rare (2 cases; no Enterobacteriaceae), but streptococcal ba cteremias were frequent in both arms (27 cases). Side effects were not significantly different, but compliance with ciprofloxacin was better . Conclusions: Ciprofloxacin is at least as effective as the combinati on of neomycin/polymyxin/ nalidixic acid in the prophylaxis of bacteri al infections in myelosuppressed patients, and is better tolerated. Ad ditional agents to prevent streptococcal infections are needed.