Once-daily dose administration of aminoglycoside in adults is effective and economical. However, its value in febrile neutropenic children, especially in Thailand, is less well researched. In the area where Pseudomonas aeruginosa prevalence in febrile neutropenic children is low, the combination of cloxacillin and amikacin is an appropriate approach. This study would like to compare the efficacy and safety including cost between these two amikacin administrations (once-daily or twice-daily) in combination with cloxacillin as an empirical therapy in febrile neutropenic children.

Hypothesis: Once-daily amikacin plus cloxacillin can be used to treat febrile neutropenic children in Khon Kaen, Thailand.

Fever: a single oral temperature of >/= 38.3 degrees C; or >/= 38.0 degrees C for >/= 1 hour.

Neutropenia: neutrophil count, < 500/cu mm or <1,000/cu mm with a predicted decrease to <500/mm3.

Inclusion Criteria:

• Aged 1 year - 14 years
• A single oral temperature of >/= 38.3 degrees C; or >/= 38.0 degrees C for >/= 1 hour.
• Neutropenia: neutrophil count, < 500/cu mm or <1,000/cu mm with a predicted decrease to <500/mm3.
• During the course of chemotherapy

Exclusion Criteria:

• History of amikacin or cloxacillin allergy
• Creatinine clearance < 30 ml/min/m2
• Central nervous system infection: meningitis or brain abscess
• History of hearing abnormality
• Severely ill: shock
• Chronic liver diseases or SGPT > 10 times of upper normal limit
• Received aminoglycoside within 14 days prior to enrolment
• Received any intravenous antibiotics within 7 days
• Cancer which is newly diagnosed or relapsed