Orphanet Journal of Rare Diseases (Mar 2023)

Mitochondrial diseases in Hong Kong: prevalence, clinical characteristics and genetic landscape

  • Tsz-sum Wong,
  • Kiran M. Belaramani,
  • Chun-kong Chan,
  • Wing-ki Chan,
  • Wai-lun Larry Chan,
  • Shek-kwan Chang,
  • Sing-ngai Cheung,
  • Ka-yin Cheung,
  • Yuk-fai Cheung,
  • Shuk-ching Josephine Chong,
  • Chi-kwan Jasmine Chow,
  • Hon-yin Brian Chung,
  • Sin-ying Florence Fan,
  • Wai-ming Joshua Fok,
  • Ka-wing Fong,
  • Tsui-hang Sharon Fung,
  • Kwok-fai Hui,
  • Ting-hin Hui,
  • Joannie Hui,
  • Chun-hung Ko,
  • Min-chung Kwan,
  • Mei-kwan Anne Kwok,
  • Sung-shing Jeffrey Kwok,
  • Moon-sing Lai,
  • Yau-on Lam,
  • Ching-wan Lam,
  • Ming-chung Lau,
  • Chun-yiu Eric Law,
  • Wing-cheong Lee,
  • Han-chih Hencher Lee,
  • Chin-nam Lee,
  • Kin-hang Leung,
  • Kit-yan Leung,
  • Siu-hung Li,
  • Tsz-ki Jacky Ling,
  • Kam-tim Timothy Liu,
  • Fai-man Lo,
  • Hiu-tung Lui,
  • Ching-on Luk,
  • Ho-ming Luk,
  • Che-kwan Ma,
  • Karen Ma,
  • Kam-hung Ma,
  • Yuen-ni Mew,
  • Alex Mo,
  • Sui-fun Ng,
  • Wing-kit Grace Poon,
  • Richard Rodenburg,
  • Bun Sheng,
  • Jan Smeitink,
  • Cheuk-ling Charing Szeto,
  • Shuk-mui Tai,
  • Choi-ting Alan Tse,
  • Li-yan Lilian Tsung,
  • Ho-ming June Wong,
  • Wing-yin Winnie Wong,
  • Kwok-kui Wong,
  • Suet-na Sheila Wong,
  • Chun-nei Virginia Wong,
  • Wai-shan Sammy Wong,
  • Chi-kin Felix Wong,
  • Shun-ping Wu,
  • Hiu-fung Jerome Wu,
  • Man-mut Yau,
  • Kin-cheong Eric Yau,
  • Wai-lan Yeung,
  • Hon-ming Jonas Yeung,
  • Kin-keung Edwin Yip,
  • Pui-hong Terence Young,
  • Gao Yuan,
  • Yuet-ping Liz Yuen,
  • Chi-lap Yuen,
  • Cheuk-wing Fung

DOI
https://doi.org/10.1186/s13023-023-02632-6
Journal volume & issue
Vol. 18, no. 1
pp. 1 – 11

Abstract

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Abstract Objective To determine the prevalence of mitochondrial diseases (MD) in Hong Kong (HK) and to evaluate the clinical characteristics and genetic landscape of MD patients in the region. Methods This study retrospectively reviewed the phenotypic and molecular characteristics of MD patients from participating public hospitals in HK between January 1985 to October 2020. Molecularly and/or enzymatically confirmed MD cases of any age were recruited via the Clinical Analysis and Reporting System (CDARS) using relevant keywords and/or International Classification of Disease (ICD) codes under the HK Hospital Authority or through the personal recollection of treating clinicians among the investigators. Results A total of 119 MD patients were recruited and analyzed in the study. The point prevalence of MD in HK was 1.02 in 100,000 people (95% confidence interval 0.81–1.28 in 100,000). 110 patients had molecularly proven MD and the other nine were diagnosed by OXPHOS enzymology analysis or mitochondrial DNA depletion analysis with unknown molecular basis. Pathogenic variants in the mitochondrial genome (72 patients) were more prevalent than those in the nuclear genome (38 patients) in our cohort. The most commonly involved organ system at disease onset was the neurological system, in which developmental delay, seizures or epilepsy, and stroke-like episodes were the most frequently reported presentations. The mortality rate in our cohort was 37%. Conclusion This study is a territory-wide overview of the clinical and genetic characteristics of MD patients in a Chinese population, providing the first available prevalence rate of MD in Hong Kong. The findings of this study aim to facilitate future in-depth evaluation of MD and lay the foundation to establish a local MD registry.

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