Pharmacokinetic of ceftazidime‐avibactam in a critically ill patient under high‐volume continuous venovenous haemodiafiltration: A first paediatric case report

Abstract

Ceftazidime‐avibactam is a novel cephalosporin/B‐lactamase inhibitor developed in the context of increasing resistance. This case reports the pharmacokinetics of ceftazidime‐avibactam in a critically ill children under continuous renal replacement (CRRT) therapy for fluid overload. Patient was a 6 months old female with sepsis due to bloodstream infection to Stenotrophomonas maltophilia following stem cell transplantation for severe combined immunodeficiency. CRRT was started on day 2. Concentrations have been monitored using liquid chromatography‐tandem mass spectrometry. Treatment was given every 8 hours with a 2 hours infusion of 30‐7,5 mg/kg and didn’t reach pharmacokinetic/pharmacodynamic targets. Total clearance was respectively 1.7 and 3.02 L/h and the part of CRRT clearance was respectively 28.8 to 60% for ceftazidime and 14 to 33% for avibactam. Those clearance are higher than reported in adult literature leading to a risk of treatment failure and emerging resistance. This support the benefit to monitor antimicrobial therapy under CRRT and the necessity to asses higher dosing or continuous infusion of ceftazidime‐avibactam.