Effect of dextran on gentamicin-induced ototoxicity

Area of Science:

• Ototoxicity research
• Pharmacology
• Auditory science

Background:

• Gentamicin (GM) is an aminoglycoside antibiotic with known nephrotoxic and ototoxic potential.
• Low-molecular-weight dextran (DX) is sometimes used in medical contexts.
• The combined effects of GM and DX on ototoxicity require investigation.

Purpose of the Study:

• To investigate the impact of low-molecular-weight dextran (DX) on gentamicin (GM)-induced ototoxicity.
• To evaluate cochlear damage and kidney function in a guinea pig model.

Main Methods:

• Guinea pigs received intramuscular gentamicin (100 mg/kg) for 10, 12, or 14 days, with or without dextran.
• Cochlear damage was assessed using compound action potential thresholds.
• Histological evaluation of cochlear hair cell loss after osmium tetroxide fixation.

Main Results:

• Combined administration of GM and DX significantly increased the percentage of missing outer hair cells.
• No significant difference in blood urea nitrogen levels was observed between groups.
• DX potentiated the ototoxic effects of GM without affecting nephrotoxicity markers.

Conclusions:

• Co-administration of aminoglycoside antibiotics like gentamicin with dextran may increase the risk of ototoxicity.
• Clinicians should be aware of the potential for enhanced hearing damage when using these agents together.
• Monitoring for ototoxicity is crucial in patients receiving combined GM and DX therapy.