Pharmacokinetic analysis of amikacin twice and single daily dosage in immunocompromised pediatric patients

Ten children received amikacin twice daily and 13 were treated using the si ngle daily protocol, All had fever and neutropenia on admission, and receiv ed a total daily dose of 20 mg/kg when included in the study, Individual ph armacokinetic parameters were calculated using a one-compartment model for two blood amikacin samples, The mean (+/- SD) of elimination half-life (h), amikacin clearance (l/h/kg), volume of distribution (l/kg), peak concentra tion (mu g/ml) and trough concentration (mu g/ml) were: 2.51 (0.74) and 2.8 5 (0.32) h; 0.26 (0.16) and 0.115 (0.02) l/h/kg; 0.74 (0.44) and 0.47 (0.11 ) l/kg; 19.1 (12.3) and 42.6 (12.6) mu g/ml; 0.85 (0.74) and 0.18 (0.24) mu g/ml with twice and single daily dosage schedules, respectively. A single daily dose of amikacin had a significantly longer elimination half-life, lo wer clearance, higher peak concentration and lower trough concentration in comparison to the twice-daily schedule. The use of amikacin 20 mg/kg daily delivered in a single daily dose is recommended for immunocompromised pedia tric patients with fever and neutropenia, in spite of the measured pharmaco kinetic differences.