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

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.

Territory-wide population-based study of chronic hepatitis C infection and implications for hepatitis elimination in Hong Kong.

BACKGROUND: To study the epidemiology of chronic hepatitis C virus infection in Hong Kong and to estimate the service gap for achieving the WHO hepatitis elimination targets of attaining a diagnosis rate of 90%, treatment rate of 80% and 65% reduction in mortality rate by 2030. METHODS: From January 2005 to March 2017, patients who were tested positive for anti-HCV were retrospectively retrieved from all public hospitals in Hong Kong. The epidemiological data of 15 participating hospitals were analysed. RESULTS: A total of 11 309 anti-HCV+ patients were identified and the estimated diagnosis rate was 50.9%. Our HCV-infected patients were ageing (median age 59). The all-cause mortality rate increased from 26.2 to 54.8 per 1000 person-years over the last decade. Our estimated treatment rate was 12.4%. Among the treated patients, 93.6% had received pegylated interferon/ribavirin (Peg-IFN/RBV) but only 10.8% had received interferon-free direct-acting antivirals (DAAs). In a cohort of 1533 patients, 39% already had advanced liver fibrosis or cirrhosis. The sustained virological response rate for Peg-IFN/RBV and DAAs were 74.8% and 97.2% respectively. However, more than 70% of patients were not subjected to interferon treatment for various reasons. Patients who achieved SVR were associated with a significantly lower risk of HCC (4.7% vs 9.6%, P = 0.005) and death (1.7% vs 23.8%, P < 0.001). CONCLUSION: Our diagnosis rate, treatment rate and mortality rate reduction were still low, particularly the Peg-IFN outcomes, making it difficult to meet the WHO hepatitis elimination targets. A more generalized use of DAAs is urgently needed to improve the situation.

Real-life efficacy and safety of paritaprevir/ritonavir, ombitasvir, and dasabuvir in chronic hepatitis C patients in Hong Kong.

BACKGROUND AND AIM: In registration studies, combination therapy of paritaprevir/ritonavir, ombitasvir, and dasabuvir (PrOD) with and without ribavirin for 12-24 weeks can achieve > 90% sustained virological response (SVR) for genotype 1 hepatitis C virus (HCV) infection. However, data in Asia is scanty. We aimed to study the efficacy and safety of this combination therapy in chronic hepatitis C patients in Hong Kong. METHODS: We retrospectively analyzed data from six local hospitals that have prescribed PrOD with and without ribavirin to patients with genotype 1 chronic HCV infection as part of a global compassionate program. RESULTS: Among 41 patients treated, 35 (85%) patients had genotype 1b HCV infection, 6 (15%) had co-infection with human immunodeficiency virus, 35 (85%) failed previous peginterferon and ribavirin therapy, 25 (61%) had compensated liver cirrhosis, and 3 (7%) had liver transplantation. Thirty-five (85%) patients received 12-week treatment and six patients received 24-week treatment; 26 (63%) patients received ribavirin combination. Thirty-nine (95%; 95% confidence interval 88.5-100%) patients had undetectable HCV RNA at 12-week post-treatment, that is, SVR. The two patients who did not develop SVR discontinued treatment prematurely; both of them were treatment experienced with liver cirrhosis complicated by acute renal failure unrelated to the treatment of PrOD and ribavirin. No patient had hepatic decompensation. CONCLUSIONS: Paritaprevir/ritonavir, ombitasvir, and dasabuvir with or without ribavirin is effective and safe in patients with genotype 1 HCV infection in real-life clinical setting in Hong Kong.