Risk of nephrotoxicity with combination vancomycin-aminoglycoside antibiotic therapy

Area of Science:

• Clinical Pharmacy
• Nephrology
• Pharmacokinetics

Background:

• Concurrent vancomycin and aminoglycoside therapy is common for severe infections.
• Nephrotoxicity is a known adverse effect of these antibiotic classes.
• Clinical pharmacokinetics services aim to optimize drug dosing and minimize toxicity.

Purpose of the Study:

• To retrospectively evaluate the incidence of nephrotoxicity in patients receiving concurrent vancomycin and aminoglycoside therapy.
• To identify risk factors associated with the development of nephrotoxicity in this patient population.

Main Methods:

• Retrospective review of 105 patients receiving at least 5 days of concurrent vancomycin and aminoglycoside therapy.
• Therapeutic drug monitoring of vancomycin and aminoglycoside serum concentrations by a clinical pharmacokinetics service.
• Logistic regression analysis to identify associations between patient factors and nephrotoxicity.

Main Results:

• Nephrotoxicity occurred in 28% of patients.
• Twenty-two patients (79%) with nephrotoxicity had other known risk factors for renal failure.
• Neutropenia and peritonitis were identified as novel risk factors associated with increased nephrotoxicity risk.

Conclusions:

• Concurrent vancomycin and aminoglycoside therapy is associated with a significant risk of nephrotoxicity.
• Factors such as age, sex, drug serum concentrations, therapy duration, and specific comorbidities (e.g., liver disease, neutropenia, peritonitis) influence this risk.
• Close monitoring of renal function and drug serum concentrations is crucial for patients receiving this combination therapy, especially those with identified risk factors.