Selective oral antimicrobial prophylaxis for the prevention of infection in acute leukaemia-ciprofloxacin versus co-trimoxazole plus colistin. The EORTC-Gnotobiotic Project Group.

230 leukaemic patients were entered into a randomised, prospective, multicentre trial of either ciprofloxacin (1 g/day) or co-trimoxazole (1920 mg/day) plus colistin (800 mg/day) for the prevention of infection during granulocytopenia. Bacteraemia due to resistant gram-negative rods occurred only in the co-trimoxazole-colistin group though both regimens were effective for selective gastrointestinal tract decontamination. However, there were fewer patients without any infective complications (31% vs. 18%: P = 0.02), fewer febrile days [mean (S.D.) 5.9 (1.1) vs. 8.2 (1.4): P = 0.0242], a lower proportion of infective events (0.9 (0.16) vs. 1.2 (0.18): P = 0.005) and fever occurred later (median 19 vs. 14 days: 0.025 less than P less than 0.05) in the co-trimoxazole-colistin group. The choice of prophylactic regimen therefore appears to depend upon whether or not protection against gram-negative infection is required or better systemic prophylaxis overall.