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Published on: January 9, 2019
Auditory function after a prolonged course of ciprofloxacin-dexamethasone otic suspension in a murine model
Katherine R Kavanagh1, Kourosh Parham, Scott R Schoem
1Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA.
Objective:
To test for ototoxicity after prolonged ototopical fluoroquinolone use in the middle ear space using a murine model.
Design:
Nonrandomized controlled trial.
Subjects:
Twelve CBA/J mice.
Interventions:
The mice received daily intratympanic injections of ciprofloxacin-dexamethasone otic suspension for 21 days. The contralateral ear received daily intratympanic injections of sterile isotonic sodium chloride solution (saline) as a control.
Main Outcome Measures:
Click-evoked auditory brainstem response (ABR) thresholds were obtained before injection and 10 days and 3 months after injection.
Results:
Mean (SEM) preinjection ABR thresholds were 47.17 (2.74) dB peak equivalent sound pressure level (peSPL) in ciprofloxacin-dexamethasone-treated ears and 45.08 (1.56) dB peSPL in saline-treated ears (P = .38). Mean (SEM) postinjection ABR thresholds in ciprofloxacin-dexamethasone-treated ears were 44.25 (1.25) dB peSPL after 10 days and 43.00 (1.51) dB peSPL after 3 months. Mean (SEM) postinjection ABR thresholds in saline-treated ears were 48.00 (1.51) dB peSPL after 10 days and 45.92 (1.79) dB peSPL after 3 months. There were no significant differences in ABR thresholds for ciprofloxacin-dexamethasone-treated ears (P = .29, P = .10) or saline-treated ears (P = .07, P = .59).
Conclusion:
Ciprofloxacin-dexamethasone suspension did not cause either immediate or delayed ototoxicity after 21 days of intratympanic administration in the CBA/J mouse model.
Insights
This study found that ciprofloxacin-dexamethasone ear drops did not cause hearing damage (ototoxicity) in mice after 21 days of use. The results indicate no immediate or delayed ototoxic effects in this animal model.
Area of Science:
- Otolaryngology
- Pharmacology
- Toxicology
Background:
- Ototopical fluoroquinolones are frequently used for middle ear infections.
- Concerns exist regarding potential ototoxicity with prolonged use.
Purpose of the Study:
- To evaluate the ototoxic potential of ciprofloxacin-dexamethasone otic suspension after prolonged intratympanic administration in a murine model.
Main Methods:
- A nonrandomized controlled trial was conducted using twelve CBA/J mice.
- Mice received daily intratympanic injections of ciprofloxacin-dexamethasone or saline (control) for 21 days.
- Auditory brainstem response (ABR) thresholds were measured before, and at 10 days and 3 months after, injections.
Main Results:
- No significant differences in ABR thresholds were observed between the ciprofloxacin-dexamethasone treated ears and the saline-treated control ears at any time point.
- Mean ABR thresholds remained stable in both groups throughout the study period.
- Neither immediate nor delayed ototoxicity was detected based on ABR measurements.
Conclusions:
- Twenty-one days of intratympanic ciprofloxacin-dexamethasone administration did not result in ototoxicity in the CBA/J mouse model.
- The findings suggest that this otic suspension is safe for middle ear use in terms of hearing function in this model.
- Further research may explore long-term effects or different administration routes.
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