Associations of HLA class II alleles with pulmonary tuberculosis in Thais

Tuberculosis is an important infectious disease in Thailand. Susceptibility to tuberculosis is influenced not only by the environment but also by host genetic factors. In this study, we investigated HLA alleles in 82 patients with tuberculosis from Bangkok and in 160 normal controls. HLA‐DRB1, DQA1 and DQB1 genotyping was performed by the PCR‐SSO method. The frequency of HLA‐DQB1*0502 was increased in tuberculosis patients compared to the normal controls (P = 0.01, OR = 2.06). In contrast, the frequencies of DQA1*0601 and DQB1*0301 were decreased in tuberculosis patients compared to the controls (P = 0.02 and P = 0.01, respect­ively). Our results suggest that HLA‐DQB1*0502 may be involved in the development of pulmonary tuberculosis, whereas HLA‐DQA1*0601 and DQB1*0301 may be associated with protection against tuberculosis.     

Association of Fcgamma receptor IIb and IIIb polymorphisms with susceptibility to systemic lupus erythematosus in Thais

We recently reported association of a newly identified polymorphism of Fcgamma receptor (FcgammaR) IIb, I232T, with systemic lupus erythematosus (SLE) in Japanese. To date, information on FcgammaR genotypes and their association with SLE is limited in South-east Asian populations. To gain further insight into the role of FcgammaR polymorphisms in the genetic predisposition of SLE, association of FcgammaRIIa-H131R, IIb-I232T, IIIa-F176V and IIIb-NA1/NA2 (HNA-1a/1b) polymorphisms with SLE was analyzed in the Thai population, using case-control association analysis. FcgammaRIIb-232T/T and IIIb-NA2/NA2 genotypes were associated with SLE with the odds ratio of 2.55. Genotype relative risk analysis revealed significant association of IIb-232T/T and IIIb-NA2/NA2, and a tendency of association of the IIIa-176F/F genotype. Moreover, carriers of FcgammaRIIa-131R were significantly increased in patients with lupus nephritis. Significant linkage disequilibrium was present among FcgammaRIIb, IIIa and IIIb, and two-locus analyses suggested that the tendency of association of FcgammaRIIIa could derive from linkage disequilibrium with IIb and IIIb. These results provided evidence that FcgammaR polymorphisms may be an important predisposing factor also in Thais in a complex manner.     

Associations of HLA class II alleles with pulmonary tuberculosis in Thais.

Tuberculosis is an important infectious disease in Thailand. Susceptibility to tuberculosis is influenced not only by the environment but also by host genetic factors. In this study, we investigated HLA alleles in 82 patients with tuberculosis from Bangkok and in 160 normal controls. HLA-DRB1, DQA1 and DQB1 genotyping was performed by the PCR-SSO method. The frequency of HLA-DQB1*0502 was increased in tuberculosis patients compared to the normal controls (P = 0.01, OR = 2.06). In contrast, the frequencies of DQA1*0601 and DQB1*0301 were decreased in tuberculosis patients compared to the controls (P = 0.02 and P = 0.01, respectively). Our results suggest that HLA-DQB1*0502 may be involved in the development of pulmonary tuberculosis, whereas HLA-DQA1*0601 and DQB1*0301 may be associated with protection against tuberculosis.     

Factors associated with tuberculosis treatment default among HIV-infected tuberculosis patients in Thailand

Ensuring completion of tuberculosis (TB) treatment remains a major public health problem. In HIV-infected patients, TB is the most common severe opportunistic infection. Few studies have evaluated risk factors for TB treatment default in HIV-infected patients. We conducted a prospective, observational study of HIV-infected TB patients in Thailand. Patients underwent standardised evaluations at the beginning of TB treatment, at the end of the intensive phase and at the end of TB treatment. TB treatment outcomes were assessed according to WHO guidelines. The analysis was limited to patients who defaulted or who had treatment success. Of the 554 patients analysed, 61 (11%) defaulted. In multivariate analysis, factors associated with TB treatment default included incarceration history [adjusted odds ratio (AOR) 2.0, 95% CI 1.1-3.7), smoking (AOR 2.3, 95% CI 1.3-4.1) and having a symptom complaint score >15 (AOR 3.4, 95% CI 1.4-8.0); one marker of wealth, namely owning a refrigerator, was protective (AOR 0.4, 95% CI 0.2-0.8). Default during TB treatment was a significant problem in HIV-infected patients. Reducing default may require enhancing services for patients with a history of incarceration or smoking and designing patient-centred systems to address poverty and patient wellness.     

Killer cell immunoglobulin-like receptors in Thai patients with leukemia and diffuse large B-cell lymphoma

Natural killer (NK) cells are key components of the innate immune system that have been implicated in the immune response against tumor cells. Killer cell immunoglobulin-like receptors (KIR) regulate NK cell activity by interaction with specific human leukocyte antigen (HLA) class I. In this study, KIR gene polymorphisms and their HLA ligands were investigated in Thai patients with chronic myelogenous leukemia (CML) (n = 60), acute myelogenous leukemia (AML) (n = 60), acute lymphoblastic leukemia (ALL) (n = 55), and diffuse large B-cell lymphoma (DLBCL) (n = 60) compared with 150 healthy controls. The frequency of KIR3DL1 with HLA-Bw4 was significantly lower in DLBCL patients than in controls (P = 0.0006, Pc = 0.02), whereas no significant differences were seen in KIR gene frequencies and their ligands between leukemia patients and controls. This study suggest a role of inhibitory KIR with its ligand in the protection against DLBCL.     

Sedative use: its association with harmful alcohol use,harmful tobacco use and quality of life among health care workers in Thailand

Background: Health care workers (HCWs) may be at higher risk for sedative misuse due to potential access and self-medication behavior.

Objectives: To examine risk factors for harmful sedative use (HSedU) and its association with harmful alcohol use (HAlcU), harmful tobacco use (HTobU) and quality of life (QoL).

Methods: A survey was conducted in 2013 at an urban university hospital in Northern Thailand. Risk of harm was measured using The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST). Harmful substance use defined as having at least moderate risk of harm. QoL was measured using SF-36 questionnaire.

Results: A sample of 3204 HCWs (59.7% response) participated. The prevalence of HSedU in past 3 months was 4.2%. Health professionals involved with prescribing or dispensing medication were at higher risk of HSedU (OR 1.80, 95% CI 1.21–2.67). Adjusting for confounders, HSedU was associated with HAlcU (OR 3.35, 95% CI 1.81–6.20) but not associated with HTobU. HSedU was associated with lower QoL score which was 7.78 and 5.52 points lower for physical (95% CI ?10.4 to ?5.18) and mental QoL (95% CI ?7.11 to ?3.93), respectively.

Conclusions: HCWs were at higher risk of HSedU. HSedU was associated with HAlcU and associated with lower physical and mental health QoL.     

Killer cell immunoglobulin-like receptors and response to antiviral treatment in Thai patients with chronic hepatitis C virus genotype 3a

Genetic factors of the host have been shown to influence the outcome of treatment for hepatitis C virus (HCV) infection. Killer cell immunoglobulin‐like receptors (KIR) regulate natural killer (NK) cell activity by interaction with specific human leukocyte antigen (HLA) class I. In this study, KIR gene polymorphisms and their HLA ligands were investigated in 110 Thai patients with chronic HCV genotype 3a. Seventy‐six patients were sustained virological responders and 34 patients were virological non‐responders. KIR typing and HLA‐C typing were performed using PCR‐SSP (polymerase chain reaction with sequence specific primer). The frequency of HLA‐C1C2 was significantly higher in sustained responders than in non‐responders (P = 0.04). However, the frequencies of KIR2DL2/2DL3 genotype and KIR2DL2/2DL3‐HLA‐C1C1 genotype were significantly higher in non‐responders than in sustained responders (P = 0.02, 0.004, respectively). In summary, this study showed the association of KIR genes and ligands with the outcome of antiviral treatment in chronic hepatic C virus genotype 3a infection. J. Med. Virol. 83:1733–1737, 2011. © 2011 Wiley‐Liss, Inc.