Quinolone resistance in neutropenic patients: the effect of prescribing policy in the UK and Pakistan.

Quinolones are increasingly used as prophylaxis in neutropenic patients to prevent serious Gram-negative septicaemias but practice is not uniform because of the controversial evidence as to their effectiveness. It is unclear if they are of real benefit in patients with short episodes of neutropenia such as those resulting from treatment for solid tumours and lymphomas. The concern over the use of ciprofloxacin in such settings is the increasing development of quinolone resistant Gram-negative bacteria. We have retrospectively analysed our bacterial isolate resistance patterns in the Queen Elizabeth Hospital (QE) and in the Haematology Department of the Aga Khan Hospital (AKU), Pakistan where all patients would receive ciprofloxacin prophylaxis when neutropenic. Seven out of 57 (12.2%) and 18 out of 55 (32.7%) Gram-negative organisms isolated from blood cultures at the QE and AKU Haematology Departments, respectively, were resistant to ciprofloxacin (P < 0.01). In the Birmingham community this was significantly lower (P < 0.01) (55 out of 6423: 0.85%). We also showed a higher level of E. coli resistance at the AKU (18 out of 31: 58%) where ciprofloxacin use was more widespread than at the QE (1 out of 11, P < 0.01). We conclude that ciprofloxacin should not be used indiscriminately.