{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T07:22:40Z","timestamp":1787642560841,"version":"build-2736575974"},"reference-count":27,"publisher":"AOSIS","issue":"1","license":[{"start":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:00:00Z","timestamp":1788134400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:p>Background:\u00a0South Africa has a high burden of multidrug-resistant tuberculosis (MDR-TB) and rifampicin-resistant tuberculosis (RR-TB). At the time of this study, kanamycin formed part of the South African MDR\/RR-TB treatment regimen. Although treatment has shifted towards shorter all-oral regimens, aminoglycoside-related ototoxicity remains clinically relevant.\nObjectives:\u00a0This study investigated the association between two mitochondrial variants, m.15312T&gt;C (I189T in\u00a0MT-CYB [mitochondrially encoded cytochrome b]) and m.10114T&gt;C (I19T in\u00a0MT-ND3 [mitochondrially encoded NADH]), and susceptibility to cochleotoxicity in South African patients receiving kanamycin-based MDR\/RR-TB treatment.\nMethod:\u00a0A prospective cohort study was conducted in Cape Town, South Africa. Hearing thresholds from 0.25 kHz to 16 kHz were monitored at baseline and at 4 weeks, 8 weeks and 12 weeks after treatment initiation. Cochleotoxicity was defined using the American Speech-Language-Hearing Association\u2019s significant threshold shift criteria. Mitochondrial variants were identified using polymerase chain reaction and Sanger sequencing. Fisher\u2019s exact tests were used to explore associations between variants and cochleotoxicity.\nResults:\u00a0Hearing data were analysed for 102 participants. Cochleotoxicity developed in 84 participants (82.4%). The m.15312T&gt;C variant was detected in three of 78 successfully sequenced participants, and m.10114T&gt;C in four of 80. All variant carriers had cochleotoxicity. Statistically significant associations were not demonstrated for m.15312T&gt;C (p\u00a0= 1.000) or m.10114T&gt;C (p\u00a0= 1.000).\nConclusion:\u00a0The variants were observed only among participants who developed cochleotoxicity, but no statistically significant associations were observed. The findings are exploratory and require validation before clinical screening.\nContribution:\u00a0This study supports future genetic-susceptibility research in African aminoglycoside-exposed populations.<\/jats:p>","DOI":"10.4102\/sajcd.v73i1.1180","type":"journal-article","created":{"date-parts":[[2026,8,25]],"date-time":"2026-08-25T07:07:59Z","timestamp":1787641679000},"update-policy":"https:\/\/doi.org\/10.4102\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Genetic susceptibility to aminoglycoside cochleotoxicity in South African multidrug-resistant and rifampicin-resistant tuberculosis patients"],"prefix":"10.4102","volume":"73","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9267-3146","authenticated-orcid":false,"given":"Nazanin","family":"Ghafari","sequence":"first","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03p74gp79","id-type":"ROR","asserted-by":"publisher"}],"name":"University of Cape Town"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9109-9103","authenticated-orcid":false,"given":"Lebogang","family":"Ramma","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03p74gp79","id-type":"ROR","asserted-by":"publisher"}],"name":"University of Cape Town"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7927-6506","authenticated-orcid":false,"given":"Richard","family":"Court","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03p74gp79","id-type":"ROR","asserted-by":"publisher"}],"name":"University of Cape Town"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0518-338X","authenticated-orcid":false,"given":"Noluthando","family":"Manyisa","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03p74gp79","id-type":"ROR","asserted-by":"publisher"}],"name":"University of Cape Town"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0982-6226","authenticated-orcid":false,"given":"Helen","family":"McIlleron","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03p74gp79","id-type":"ROR","asserted-by":"publisher"}],"name":"University of Cape Town"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9385-4731","authenticated-orcid":false,"given":"Lucretia","family":"Petersen","sequence":"additional","affiliation":[{"id":[{"id":"https:\/\/ror.org\/03p74gp79","id-type":"ROR","asserted-by":"publisher"}],"name":"University of Cape Town"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2580","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"key":"ref0","unstructured":"American Speech-Language-Hearing Association (ASHA). 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