[Amikacin concentration in the severely obstructed urinary tract]

Area of Science:

• Pharmacology
• Nephrology
• Urology

Context:

• Severely unilateral ureteral obstruction can impact drug pharmacokinetics.
• Understanding antibiotic concentrations in urine is crucial for effective treatment.
• Amikacin is an antibiotic commonly used for serious infections.

Purpose:

• To determine urinary amikacin concentrations in patients with severe unilateral ureteral obstruction.
• To compare amikacin levels in obstructed versus normal urinary tracts.
• To provide dosing recommendations for amikacin in obstructed urinary systems.

Summary:

• Urinary amikacin concentrations were measured in 9 patients with severe unilateral ureteral obstruction following intravenous infusion.
• The average concentration in the obstructed tract was 118.9 mcg/ml at 6 hours, while the normal kidney showed concentrations of 155.9, 98.8, and 83.3 mcg/ml over 6 hours.
• Urinary excretion from the obstructed tract was approximately one-third of that from a normal system.

Impact:

• Findings suggest that 100 mg of intravenous amikacin may offer prophylactic urinary levels in obstructed tracts.
• Higher doses (≥200 mg IV) are recommended for treating active infections in severely obstructed urinary tracts.
• This research aids in optimizing amikacin dosing strategies for patients with ureteral obstruction.