Imipenem-cilastatin versus piperacillin-tazobactam as monotherapy in febrile neutropenia

Background: In view of the recent trend toward monotherapy in the treatment of febrile neutropenia, we evaluated the clinical efficacy and safety of imipenem-cilastatin versus piperacillin-tazobactam as an empiric therapy for febrile neutropenia in children with malignant diseases. Methods: Febrile neutropenic patients received either imipenem-cilastatin or piperacillin-tazobactam randomly. Improvement without any changes in the initial antibiotic treatment was defined as "success" and improvement with modification of the initial treatment and death was defined as "failure". Results: Over 12 months, 99 febrile neutropenic episodes were treated with monotherapy in 63 patients with a median age of 5 years. At admission, median absolute neutrophil count was 50/mm3 and in 67% of episodes, neutrophil count was under 100/mm3. Median duration of neutropenia was 5 days. In 22% of episodes, neutropenia persisted for more than 10 days. Piperacillin-tazobactam was used in 52 episodes and imipenem-cilastatin was used in 47 episodes. There was no difference between groups in terms of age, sex, primary diseases, neutrophil count or duration of neutropenia. In the whole group, the success rate was 67% and the failure rate was 33%, whereas in the piperacillin-tazobactam group, the rates were 71% and 29%; and in the imipenem-cilastatin group they were 62% and 38%, respectively (P > 0.05). There were no deaths. No major adverse effects were seen in either group. Conclusions: Although failure was slightly higher in the imipenem-cilastatin group, this was statistically insignificant. Both of these antibiotics can be used safely for initial empirical monotherapy of febrile neutropenia.