Aminoglycosides, deafness, and non-tuberculous mycobacteria

Kavita Prasad and colleagues’ study1Prasad K Borre ED Dillard LK et al.Priorities for hearing loss prevention and estimates of global cause-specific burdens of hearing loss: a systematic rapid review.Lancet Glob Health. 2024; 12: e217-e225Summary Full Text Full Text PDF PubMed Scopus (2) Google Scholar addressing the global burden of deafness is very timely, particularly preventable causes related to anti-infective therapies (32·4 million cases per annum). Appropriate aminoglycoside prescribing is essential for individual clinical benefit, to reduce ototoxicity and, more broadly, to reduce the development of antimicrobial resistance. Ototoxicity monitoring is often neglected when aminoglycosides are used. This is especially true in specific populations, such as those with cystic fibrosis and in low-income and middle-income countries, where audiology services are scarce, making early diagnosis of hearing loss difficult. At least for multidrug-resistant tuberculosis therapy, aminoglycoside use should decline as recent studies showed that aminoglycosides had only modest activity against multidrug-resistant tuberculosis and are being replaced by newer WHO-recommended treatment regimens.2WHOWHO operational handbook on tuberculosis. Module 4: treatment—drug-resistant tuberculosis treatment, 2022 update. World Health Organization, Geneva2022Google Scholar However, one relevant and related group of infections, not considered in the study were those caused by non-tuberculous mycobacteria. This is due to a scarcity of reliable data for incidence and outcomes because there is usually no mandatory reporting of non-tuberculous mycobacteria, unlike tuberculosis, and most laboratories in low-income and middle-income countries are unable to identify non-tuberculous mycobacteria. Nevertheless, global rates of non-tuberculous mycobacteria have increased drastically. Annual incidence of pulmonary non-tuberculous mycobacteria disease increased from 3·13 to 4·73 per 100 000 person-years between 2008 and 2015, with an average increase in yearly incidence of 5·2%.3Seddon P Fidler K Raman S et al.Prevalence of nontuberculous mycobacteria in cystic fibrosis clinics, United Kingdom, 2009.Emerg Infect Dis. 2013; 19: 1128-1130Crossref PubMed Scopus (41) Google Scholar, 4Bhanushali J Jadhav U Ghewade B Wagh P Unveiling the clinical diversity in nontuberculous mycobacteria (NTM) infections: a comprehensive review.Cureus. 2023; 15e48270Google Scholar Guideline-based treatment of non-tuberculous mycobacteria frequently relies on prolonged use of aminoglycosides.5Daley CL Iaccarino JM Lange C et al.Treatment of nontuberculous mycobacterial pulmonary disease: an official ATS/ERS/ESCMID/IDSA clinical practice guideline.Clin Infect Dis. 2020; 71: 905-913Crossref PubMed Scopus (261) Google Scholar Despite mandating audiological testing, this is not always done before aminoglycoside treatment begins and often testing is done only when the patient has clinical symptoms. There is frequently a shortage of audiology capacity or reduced access, as occurred during the COVID-19 pandemic. Estimates of treatment outcomes for non-tuberculous mycobacteria are usually poor5Daley CL Iaccarino JM Lange C et al.Treatment of nontuberculous mycobacterial pulmonary disease: an official ATS/ERS/ESCMID/IDSA clinical practice guideline.Clin Infect Dis. 2020; 71: 905-913Crossref PubMed Scopus (261) Google Scholar but, in practice, the actual success rates are unclear because aminoglycoside doses are reduced or stopped when clinically significant ototoxicity occurs, undermining cure rates. In 2023, we did a survey of doctors who were members of the European Society for Clinical Microbiology and Infectious Diseases Mycobacterial Sub-Group and found that although 62 (85%) of 73 respondents followed national or international treatment guidelines for non-tuberculous mycobacteria, including the use of aminoglycosides, 47 (64%) of 73 would stop aminoglycosides if ototoxicity was reported by the patient, even when it was believed to be an essential drug.5Daley CL Iaccarino JM Lange C et al.Treatment of nontuberculous mycobacterial pulmonary disease: an official ATS/ERS/ESCMID/IDSA clinical practice guideline.Clin Infect Dis. 2020; 71: 905-913Crossref PubMed Scopus (261) Google Scholar If we are to truly understand optimal aminoglycoside therapy, we need to improve audiology services, including implementation of portable digital audiology screening methods6Vijayasingam A Frost E Wilkins J et al.Tablet and web-based audiometry to screen for hearing loss in adults with cystic fibrosis.Thorax. 2020; 75: 632-639Crossref PubMed Scopus (12) Google Scholar and consider the use and further development of otoprotectants to reduce hearing loss. We declare no competing interests. Priorities for hearing loss prevention and estimates of global cause-specific burdens of hearing loss: a systematic rapid reviewThe global burden of preventable hearing loss is large. Hearing loss that is attributable to disease sequelae or ototoxic medications contributes substantially to the global burden of hearing loss. Prevention of these conditions should be a global health priority. Full-Text PDF Open Access