Changes in the epidemiology and clinical manifestations of human immunodeficiency virus-associated tuberculosis in Hong Kong.

INTRODUCTION: Human immunodeficiency virus (HIV)-associated tuberculosis (TB) remains an important health challenge worldwide. Although TB prevalence has decreased in the general population, there is limited information regarding temporal trends in the incidence of HIV-associated TB in Hong Kong. There are also insufficient data regarding changes in clinical manifestation patterns among HIV-associated TB patients over time. This study aimed to describe temporal trends in the epidemiology and clinical manifestations of HIV-associated TB in Hong Kong. METHODS: We retrospectively reviewed data regarding HIV-associated TB patients that were reported to the TB-HIV Registry of the Department of Health during the period 2007 to 2020. Trends of TB as a primary acquired immunodeficiency syndrome (AIDS)-defining illness, as well as changes in demographic features and clinical manifestations of HIV-associated TB during this period were examined using Cochran-Armitage trend test. RESULTS: A decreasing trend was observed in the proportion of all reported cases of AIDS in which TB was a primary AIDS-defining illness during the study period. The proportions of female patients and patients with extrapulmonary involvement significantly increased, whereas the proportions of ever-smokers and patients with sputum smear positivity significantly decreased during the same period. A decreasing trend was observed in the proportion of patients with pulmonary TB in which the lower zone was the predominant site of lung parenchymal lesions. Among patients with a diagnosis of HIV infection before TB, an increasing trend was observed in the proportion of patients receiving antiretroviral therapy. CONCLUSION: Important temporal changes were observed in the epidemiology and clinical manifestations of HIV-associated TB. These results highlight the need for continued surveillance regarding the patterns of demographic features and clinical manifestations to inform policymakers when planning control strategies for HIV-associated TB.

Delayed diagnosis of tuberculosis: risk factors and effect on mortality among older adults in Hong Kong.

OBJECTIVE: To assess the risk factors and effects of delayed diagnosis on tuberculosis (TB) mortality in Hong Kong. METHODS: All consecutive patients with TB notified in 2010 were tracked through their clinical records for treatment outcome until 2012. All TB cases notified or confirmed after death were identified for a mortality survey on the timing and causes of death. RESULTS: Of 5092 TB cases notified, 1061 (20.9%) died within 2 years of notification; 211 (4.1%) patients died before notification, 683 (13.4%) died within the first year, and 167 (3.3%) died within the second year after notification. Among the 211 cases with TB notified after death, only 30 were certified to have died from TB. However, 52 (24.6%) died from unspecified pneumonia/sepsis possibly related to pulmonary TB. If these cases are counted, the total TB-related deaths increases from 191 to 243. In 82 (33.7%) of these, TB was notified after death. Over 60% of cases in which TB diagnosed after death involved patients aged ≥80 years and a similar proportion had an advance care directive against resuscitation or investigation. Independent factors for TB notified after death included female sex, living in an old age home, drug abuse, malignancy other than lung cancer, sputum TB smear negative, sputum TB culture positive, and chest X-ray not done. CONCLUSIONS: High mortality was observed among patients with TB aged ≥80 years. Increased vigilance is warranted to avoid delayed diagnosis and reduce the transmission risk, especially among elderly patients with co-morbidities living in old age homes.

Immigrants and tuberculosis in Hong Kong.

OBJECTIVE: To examine the impact of immigrant populations on the epidemiology of tuberculosis in Hong Kong. DESIGN: Longitudinal cohort study. SETTING: Hong Kong. PARTICIPANTS: Socio-demographic and disease characteristics of all tuberculosis notifications in 2006 were captured from the statutory tuberculosis registry and central tuberculosis reference laboratory. Using 2006 By-census population data, indirect sex- and age-standardised incidence ratios by place of birth were calculated. Treatment outcome at 12 months was ascertained from government tuberculosis programme record forms, and tuberculosis relapse was tracked through the notification registry and death registry up to 30 June 2013. RESULTS: Moderately higher sex- and age-standardised incidence ratios were observed among various immigrant groups: 1.06 (Mainland China), 2.02 (India, Pakistan, Bangladesh), 1.59 (Philippines, Thailand, Indonesia, Nepal), and 3.11 (Vietnam). Recent Mainland migrants had a lower sex- and age-standardised incidence ratio (0.51 vs 1.09) than those who immigrated 7 years ago or earlier. Age younger than 65 years, birth in the Mainland or the above Asian countries, and previous treatment were independently associated with resistance to isoniazid and/or rifampicin. Older age, birth in the above Asian countries, non-permanent residents, previous history of treatment, and resistance to isoniazid and/or rifampicin were independently associated with poor treatment outcome (other than cure/treatment completion) at 1 year. Birth outside Hong Kong was an independent predictor of relapse following successful completion of treatment (adjusted hazard ratio=1.76; 95% confidence interval, 1.07-2.89; P=0.025). CONCLUSION: Immigrants carry with them a higher tuberculosis incidence and/or drug resistance rate from their place of origin. The higher drug resistance rate, poorer treatment outcome, and excess relapse risk raise concern over secondary transmission of drug-resistant tuberculosis within the local community.

Chest radiograph screening for tuberculosis in a Hong Kong prison.

SETTING: Long-stay prisoners are not regularly screened for TB in Hong Kong. OBJECTIVE: To evaluate tuberculosis (TB) screening in prison. METHOD: All prisoners in a maximum security prison as of 31 October 2001 were screened by chest radiograph (CXR), except for those being followed up for TB or examined by CXR in the last 6 months. RESULTS: A total of 814 male prisoners aged 34.6 +/- 9.6 (mean +/- SD) years were successfully screened. Of 53 cases (6.51%) with radiographic abnormalities, 10 active TB cases (8 culture-negative, 2 culture-positive) were diagnosed, giving an overall yield of 1.23% (95%CI 0.59-2.26). There was no statistical difference in age, ethnicity, place of birth or residency status between those with and those without TB (all P > 0.05). Incarceration > or = 2 years, being in current prison > or = 2 years and not having CXR in last 2 years were associated with TB in univariate analysis (all P < 0.05), but only the last remained an independent predictor in multiple logistic regression (OR 16.8, 95%CI 2.1-132.9, P = 0.008). In that group, the yield was 3.1% (95%CI 1.42-5.89). No further cases were detected in the subsequent 2 years. CONCLUSION: CXR screening of long-stay prisoners gave a high yield in this study.