Poor agreement between diagnostic tests for latent tuberculosis infection among HIV-infected persons in Hong Kong.

Background And Objective: The tuberculin skin test (TST), T-Spot.TB (T-Spot) and QuantiFERON-TB Gold-In Tube (QFT) were compared in diagnosing latent tuberculosis infection (LTBI) among human immunodeficiency virus (HIV)-infected persons.

Methods: Human immunodeficiency virus-infected persons without previous history of tuberculosis or LTBI were simultaneously tested by TST, T-Spot and QFT annually and followed up for tuberculosis.

T-Spot.TB outperforms tuberculin skin test in predicting development of active tuberculosis among household contacts.

Background And Objective: In Hong Kong, neonatal Bacillus Calmette-Guerin (BCG) vaccination is practiced with 99% coverage. This study was to compare the performance of T-Spot.TB and tuberculin skin test (TST) in predicting tuberculosis (TB) among household contacts.

Spirometry is underused in the diagnosis and monitoring of patients with chronic obstructive pulmonary disease (COPD).

Spirometry is important in the diagnosis and management of chronic obstructive pulmonary disease (COPD), yet it is a common clinical observation that it is underused though the extent is unclear. This survey aims to examine the use of spirometry in the diagnosis and management of COPD patients in a district in Hong Kong. It is a cross-sectional survey involving four clinic settings: hospital-based respiratory specialist clinic, hospital-based mixed medical specialist clinic, general outpatient clinic (primary care), and tuberculosis and chest clinic.

WHO group 5 drugs and difficult multidrug-resistant tuberculosis: a systematic review with cohort analysis and meta-analysis.

It is often necessary to include WHO group 5 drugs in the treatment of extensively drug-resistant tuberculosis (XDR-TB) and fluoroquinolone-resistant multidrug-resistant tuberculosis (MDR-TB). As clinical evidence about the use of group 5 drugs is scarce, we conducted a systematic review using published individual patient data. We searched PubMed and OvidSP through 7 April 2013 for publications in English to assemble a cohort with fluoroquinolone-resistant MDR-TB treated with group 5 drugs.

Can intermittent dosing optimize prolonged linezolid treatment of difficult multidrug-resistant tuberculosis?

We evaluated treatment with linezolid, dosed at 800 mg once daily for 1 to 4 months as guided by sputum culture status and tolerance and then at 1,200 mg thrice weekly until ≥ 1 year after culture conversion, in addition to individually optimized regimens among 10 consecutive patients with extensively drug-resistant tuberculosis or fluoroquinolone-resistant multidrug-resistant tuberculosis. All achieved stable cure, with anemia corrected and neuropathy stabilized, ameliorated, or avoided after switching to intermittent dosing. Serum linezolid profiles appeared better optimized.

Association of polymorphisms in the Chr18q11.2 locus with tuberculosis in Chinese population.

A GWAS study has reported that two single nucleotide polymorphisms (SNPs) were associated with predisposition to tuberculosis (TB) in African populations. These two loci represented the long-waited GWAS hits for TB susceptibility. To determine whether these two SNPs are associated with TB in Chinese population, we attempted an replication in a cohort of over one thousand Chinese TB patients and 1,280 healthy controls using melting temperature shift allele-specific genotyping analysis.

Transmission of multidrug-resistant and extensively drug-resistant tuberculosis in a metropolitan city.

Multidrug-resistant (MDR)- tuberculosis (TB) and extensively drug resistant (XDR)-TB reportedly lead to increased household transmission. This is a retrospective cohort study of active TB occurring among household contacts exposed to MDR-TB. Of 704 contacts in 246 households, initial screening identified 12 (1.

Pyrazinamide may improve fluoroquinolone-based treatment of multidrug-resistant tuberculosis.

The role of pyrazinamide in the current treatment of multidrug-resistant (MDR) tuberculosis (TB) is uncertain. From a territory-wide registry of MDR-TB cases diagnosed between 1995 and 2009, we assembled a cohort of 194 patients with MDR pulmonary TB given fluoroquinolone-containing regimens. Stratified by pyrazinamide use and susceptibility, there were 83 users with pyrazinamide-susceptible MDR-TB (subgroup A), 24 users with pyrazinamide-resistant MDR-TB (subgroup B), 40 nonusers with pyrazinamide-susceptible MDR-TB (subgroup C), and 47 nonusers with pyrazinamide-resistant MDR-TB (subgroup D).

A strong tuberculin reaction in primary school children predicts tuberculosis in adolescence.

Background: In Hong Kong, neonatal bacillus Calmette-Guerin vaccination coverage has been around 99% since 1970. Children younger than 14 years of age appear to have a relatively low risk of tuberculosis (TB), but the risk of TB increases rapidly after 15 years of age to a secondary peak in young adulthood.

Methods: We followed prospectively 19,383 students who were 6 to 10 years of age participating in the 1999/2000 bacillus Calmette-Guerin revaccination program by cross-matching with the territory-wide TB registry until December 31, 2010, using the identity card number as a unique identifier.

T-Spot.TB outperforms tuberculin skin test in predicting tuberculosis disease.

Rationale: Silicosis is a well-recognized risk factor for tuberculosis (TB).

Objectives: To compare T-Spot.TB with tuberculin skin test (TST) in predicting the development of TB.

CISH and susceptibility to infectious diseases.

Background: The interleukin-2-mediated immune response is critical for host defense against infectious pathogens. Cytokine-inducible SRC homology 2 (SH2) domain protein (CISH), a suppressor of cytokine signaling, controls interleukin-2 signaling.

Methods: Using a case-control design, we tested for an association between CISH polymorphisms and susceptibility to major infectious diseases (bacteremia, tuberculosis, and severe malaria) in blood samples from 8402 persons in Gambia, Hong Kong, Kenya, Malawi, and Vietnam.

The transmission dynamics of tuberculosis in a recently developed Chinese city.

Background: Hong Kong is an affluent subtropical city with a well-developed healthcare infrastructure but an intermediate TB burden. Declines in notification rates through the 1960s and 1970s have slowed since the 1980s to the current level of around 82 cases per 100 000 population. We studied the transmission dynamics of TB in Hong Kong to explore the factors underlying recent trends in incidence.

Choice of spirometric reference values for compensation assessment.

Background And Objective: Two sets of local reference values are available for spirometry in Hong Kong, but it is uncertain how well they work in the assessment of occupational lung diseases. This study examined their relative performance in the compensational assessment of silicosis.

Methods: Local reference values published in 1982 and 2006 were compared in two different populations comprising normal construction/quarry workers and silicosis patients.

Treatment of multidrug-resistant and extensively drug-resistant tuberculosis: current status and future prospects.

Drug resistance in Mycobacterium tuberculosis arises from the man-made selection of mutants that result from spontaneous chromosomal alterations. Preventing the development of drug-resistant TB through a good control program based on directly observed treatment, short-course, is of paramount importance. Established multidrug-resistant (MDR)-TB requires alternative specific chemotherapy, comprising drugs with higher cost and greater toxicity delivered on a programmatic basis.

Genetic association between a chemokine gene CXCL-10 (IP-10, interferon gamma inducible protein 10) and susceptibility to tuberculosis.

Background: Previous studies showed that activation of CXCL-10 and other chemokines were prominent in many infectious diseases. These chemokines are components of innate immune response to respiratory tract pathogens. We examined the promoter variants of CXCL-10 and their role in predisposition to tuberculosis (TB).

Comparison of intracellular cytokine flow cytometry and an enzyme immunoassay for evaluation of cellular immune response to active tuberculosis.

A prospective cross-sectional blinded study of 28 patients (21 male and 7 female patients; mean age, 44 years) with suspected active tuberculosis (TB) attending a TB and chest clinic is described. Blood was taken for immune cell enumeration, a whole-blood enzyme-linked immunosorbent assay (ELISA) for the detection of gamma interferon (IFN-gamma) by the QuantiFERON-TB Gold (QFT-G) assay, and intracellular cytokine flow cytometry (ICC) analysis; and sputum was simultaneously taken for bacteriological culture for Mycobacterium tuberculosis. Twelve healthy subjects were included as controls.

Sputum cytology examination followed by autofluorescence bronchoscopy: a practical way of identifying early stage lung cancer in central airway.

Background: The prognosis of early stage lung cancer was superior to that of late stages. We hypothesize that by using sputum cytology as the first screening method followed by autofluorescence bronchoscopy could detect early stage lung cancer in the central airway.

Methods: During 18-month recruitment period, subjects at high risk for lung cancer (ever smoker accumulated more than 20 pack-year and above 40 years) followed up at Chest Clinics were invited to submit sputum for cytological examination.

[A retrospective cohort study on mortality among silicotic workers in Hong Kong with emphasis on lung cancer].

Objective: To investigate the relationship between silica or silicosis and lung cancer in a large cohort of silicotic workers in Hong Kong.

Methods: All workers with silicosis in Hong Kong diagnosed between 1981 and 1998 were followed up till the end of 1999 to ascertain their vital status and causes of death, using the corresponding mortality rates of Hong Kong males of the same period as external comparison. Standardized mortality ratios (SMR) for lung cancer and other major causes of death were calculated.