Options and limitations of long-term oral ciprofloxacin as antibacterial prophylaxis in allogeneic bone marrow transplant recipients.

The efficacy and safety of ciprofloxacin as long-term antibacterial prophylaxis after allogeneic bone marrow transplantation were assessed prospectively. Eighty-nine recipients of lymphocyte-depleted marrow grafts were each given ciprofloxacin orally, 500 mg twice daily. Fever developed in 71 out of 78 evaluable patients (91%) and was accompanied by positive blood cultures in 42 cases (59%). 'Viridans' streptococci, all but one with reduced in vitro susceptibility to ciprofloxacin, accounted for 35 episodes of bacteraemia. Thirty-three episodes occurred in patients given anthracyclines compared with only two episodes in other patients (chi 2 = 5.58: p less than 0.05). All bacteraemic fevers occurred within 11 days post-transplant. Gram-negative sepsis did not occur in any patient. Sixteen patients died but none due to a bacterial cause. Allergy to ciprofloxacin was registered in three out of 76 assessable cases (4%).