Pharmacokinetics of Metronidazole During Prolonged Intermittent Kidney Replacement Therapy

Acute kidney injury is a common complication present in critically ill patients and is often managed by kidney replacement therapy. Prolonged intermittent kidney replacement therapy (PIKRT) is a modality of kidney replacement therapy often utilized in intensive care settings, but dosing recommendations and pharmacokinetic data for antimicrobial removal during PIKRT are limited. Metronidazole, a 5-nitroimidazole agent, is commonly prescribed for anaerobic and protozoal infections. Although generally well tolerated, adverse effects including severe neurotoxicity have been reported in association with prolonged or high cumulative dosing, particularly in the setting of kidney or hepatic impairment. In this case study, we describe and discuss the pharmacokinetics of metronidazole and the hydroxy-metabolite (hydroxy-metronidazole) concentrations in a critically ill patient undergoing PIKRT.