Occurrence and risk of cochleotoxicity in cystic fibrosis patients receiving repeated high-dose aminoglycoside therapy.
Cystic fibrosis (CF) patients receive repeated courses of aminoglycoside therapy. These patients would consequently be expected to be more susceptible to cochleotoxicity, a recognized side effect with single courses of aminoglycoside therapy. The primary aim of this retrospective study was to establish the incidence and severity of auditory deficit in CF patients. Standard (0.25- to 8-kHz) and high-frequency (10- to 16-kHz) pure-tone audiometry was carried out in 70 CF patients, and the results were compared with the results from 91 control subjects. These subjects were further divided into pediatric and adult groups. Of 70 CF patients, 12 (1 pediatric) displayed hearing loss considered to be caused by repeated exposure to aminoglycosides. There was a nonlinear relationship between the courses of therapy received and the incidence of hearing loss. The severity of the loss did not appear to be related to the number of courses received. Assuming the risk of loss to be independent for each course, preliminary estimates of per course risk of hearing loss were less than 2%. Upon comparison with previous clinical studies and experimental work, these findings suggest that the incidence of cochleotoxicity in CF patients is considerably lower than would be expected, suggesting that the CF condition may confer protection against aminoglycoside cochleotoxicity.
Mulheran
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MRC Toxicology Unit, University of Leicester, Leicester LE1 9HN, United Kingdom. mm22@le.ac.uk
Degg
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Burr
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Morgan
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Stableforth
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D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood / Q000627:therapeutic use; D001301:Audiometry, Pure-Tone; D002648:Child; D003550:Cystic Fibrosis / Q000097:blood / Q000188:drug therapy*; D003638:Deafness / Q000139:chemically induced*; D062787:Drug Overdose; D004359:Drug Therapy, Combination; D004363:Drug Utilization / Q000639:trends; D005839:Gentamicins / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood / Q000627:therapeutic use; D006309:Hearing / Q000187:drug effects; D006801:Humans; D011846:Radio Waves; D014031:Tobramycin / Q000008:administration & dosage / Q000009:adverse effects* / Q000097:blood / Q000627:therapeutic use
D000900:Anti-Bacterial Agents; D005839:Gentamicins; D014031:Tobramycin