The new fluorinated quinolones for antimicrobial prophylaxis in neutropenic cancer patients.

Fluoroquinolones are the most attractive agents for prophylactic use in neutropenic cancer patients, due to their broad antimicrobial spectrum, high concentration in the faeces, systemic bactericidal activity, uncommon emergence of resistant strains and good tolerability. They have proved to be more effective than placebo, oral non-absorbable antibiotics or cotrimoxazole in the prevention of Gram-negative infections. In a prospective, randomised multicentre study performed by the GIMEMA infection program, ciprofloxacin was demonstrated to be more effective than norfloxacin for the reduction of febrile episodes, use of systemic antibiotics, and Gram-negative infections in neutropenic patients with haematological malignancies. The greater efficacy may be related to its better systemic or greater antibacterial activity. The potential problems related to the prophylactic use of fluoroquinolones are the increasing prevalence of Gram-positive infections caused by streptococci and coagulase-negative staphylococci; the reported emergence and nosocomial spread of resistant strains, especially among coagulase-negative staphylococci; the lack of their usefulness as empirical therapy in febrile neutropenic patients. Fluoroquinolones are today the better choice for preventing Gram-negative infections in neutropenic patients and ciprofloxacin should probably be preferred. More information on their efficacy and their relationship to the overall susceptibility of micro-organisms in patients with cancer would be valuable, and careful monitoring of patients treated with these drugs is therefore warranted.