Gentamicin serum concentration measurement in children

Area of Science:

• Pediatric Infectious Diseases
• Clinical Pharmacology
• Pharmacokinetics

Background:

• Gentamicin is a critical antibiotic for serious pediatric infections.
• Standard practice in Norway involves measuring pre-dose (trough) serum gentamicin concentrations to monitor toxicity risk.
• The clinical utility of this monitoring in pediatric populations in Norway has not been previously assessed.

Purpose of the Study:

• To evaluate the clinical significance of routine pre-dose serum gentamicin concentration measurements in pediatric patients in Norway.
• To determine the frequency of elevated trough gentamicin levels in children treated according to Norwegian guidelines.

Main Methods:

• A retrospective study analyzing routine pre-dose serum gentamicin samples from pediatric patients (1 month to 17 years) across four Norwegian hospitals.
• Clinical data were extracted from electronic medical records for patients receiving intravenous gentamicin at 7 mg/kg once daily.
• Analysis included 1,288 treatment episodes for serum gentamicin levels and data from 353 episodes for treatment duration.

Main Results:

• The most common indications for gentamicin treatment were febrile urinary tract infection, febrile neutropenia, and suspected sepsis.
• In 95% of 1,288 treatment episodes, pre-dose serum gentamicin concentrations were below 0.6 mg/L.
• Only 7 episodes (0.5%) showed elevated pre-dose gentamicin concentrations (>1.0 mg/L).

Conclusions:

• Routine pre-dose serum gentamicin monitoring in pediatric patients is infrequently associated with elevated levels.
• This monitoring may be best reserved for children undergoing long-term gentamicin therapy, those with renal impairment, or those concurrently using nephrotoxic/ototoxic medications.