Background: Antibiotics have been widely and efficaciously used for febrile neutropenia in pediatric patients. However, reports are scant regarding the risk factors for recurrent fever after discontinuation of antibiotics in a neutropenic state. Here, we investigated these factors using data from our previously reported randomized study regarding meropenem and piperacillin/tazobactam for pediatric patients with febrile neutropenia. Procedure: We analyzed a total of 170 febrile episodes where first line antibiotic treatment was effective and discontinued before neutrophil recovery. Results: Recurrent fever was observed in 31 episodes (18%). The median interval from antibiotics discontinuation to recurrent fever was 5 days (0–27 days). Risk factors for recurrent fever were: incomplete remission of original disease; and high white blood cell count, neutrophil count, and C reactive protein levels at start of antibiotics. Moreover, lower neutrophil count at discontinuation of antibiotics, duration of neutropenia, and onset day of febrile neutropenia from start of neutropenia were also risk factors of recurrent fever. In multivariate analysis, neutrophil count at discontinuation of antibiotics
