Norfloxacin prophylaxis for neutropenic patients undergoing bone marrow transplantation.

To prevent bacterial infections in the neutropenic post-transplant period, norfloxacin 400mg twice daily was administered as oral prophylaxis to 44 marrow recipients isolated in laminar airflow rooms (LAFRs). Patients had a mean age of 30 years (8-50) and a male/female ratio of 29/15. The mean duration of prophylaxis was of 41 days (20-80), that of neutropenia (PMN less than 1000 x 10(6)/l) of 31 days (6-76) and that of severe neutropenia (PMN less than 100 x 10(6)/l) of 19 days (10-55). All but two patients developed one or more febrile episodes (total episodes: 71), 33 of which were documented infections. Eighteen bacteraemias occurred and all were caused by Gram-positive cocci: five by coagulase-negative staphylococci (three methicillin resistant), four by coagulase-positive (one methicillin resistant), seven by streptococci (four S. sanguis, one S. milleri, one group B, one group C), and two by enterococci. All streptococcal and enterococcal strains, but only one MR coagulase-positive staphylococcus, proved to be resistant to norfloxacin. Norfloxacin was well tolerated and no prophylactic course had to be interrupted because of side effects. In conclusion, norfloxacin adequately prevents infections caused by Gram-negative bacilli in bone marrow recipients isolated in LAFRs, but Gram-positive infections still remain a problem in these patients indicating the need for improving this prophylactic regimen.