Frequency and mortality rate following antimicrobial-resistant bloodstream infections in tertiary-care hospitals compared with secondary-care hospitals.

There are few studies comparing proportion, frequency, mortality and mortality rate following antimicrobial-resistant (AMR) infections between tertiary-care hospitals (TCHs) and secondary-care hospitals (SCHs) in low and middle-income countries (LMICs) to inform intervention strategies. The aim of this study is to demonstrate the utility of an offline tool to generate AMR reports and data for a secondary data analysis. We conducted a secondary-data analysis on a retrospective, multicentre data of hospitalised patients in Thailand. Routinely collected microbiology and hospital admission data of 2012 to 2015, from 15 TCHs and 34 SCHs were analysed using the AMASS v2.0 (www.amass.website). We then compared the burden of AMR bloodstream infections (BSI) between those TCHs and SCHs. Of 19,665 patients with AMR BSI caused by pathogens under evaluation, 10,858 (55.2%) and 8,807 (44.8%) were classified as community-origin and hospital-origin BSI, respectively. The burden of AMR BSI was considerably different between TCHs and SCHs, particularly of hospital-origin AMR BSI. The frequencies of hospital-origin AMR BSI per 100,000 patient-days at risk in TCHs were about twice that in SCHs for most pathogens under evaluation (for carbapenem-resistant Acinetobacter baumannii [CRAB]: 18.6 vs. 7.0, incidence rate ratio 2.77; 95%CI 1.72-4.43, p<0.001; for carbapenem-resistant Pseudomonas aeruginosa [CRPA]: 3.8 vs. 2.0, p = 0.0073; third-generation cephalosporin resistant Escherichia coli [3GCREC]: 12.1 vs. 7.0, p<0.001; third-generation cephalosporin resistant Klebsiella pneumoniae [3GCRKP]: 12.2 vs. 5.4, p<0.001; carbapenem-resistant K. pneumoniae [CRKP]: 1.6 vs. 0.7, p = 0.045; and methicillin-resistant Staphylococcus aureus [MRSA]: 5.1 vs. 2.5, p = 0.0091). All-cause in-hospital mortality (%) following hospital-origin AMR BSI was not significantly different between TCHs and SCHs (all p>0.20). Due to the higher frequencies, all-cause in-hospital mortality rates following hospital-origin AMR BSI per 100,000 patient-days at risk were considerably higher in TCHs for most pathogens (for CRAB: 10.2 vs. 3.6,mortality rate ratio 2.77; 95%CI 1.71 to 4.48, p<0.001; CRPA: 1.6 vs. 0.8; p = 0.020; 3GCREC: 4.0 vs. 2.4, p = 0.009; 3GCRKP, 4.0 vs. 1.8, p<0.001; CRKP: 0.8 vs. 0.3, p = 0.042; and MRSA: 2.3 vs. 1.1, p = 0.023). In conclusion, the burden of AMR infections in some LMICs might differ by hospital type and size. In those countries, activities and resources for antimicrobial stewardship and infection control programs might need to be tailored based on hospital setting. The frequency and in-hospital mortality rate of hospital-origin AMR BSI are important indicators and should be routinely measured to monitor the burden of AMR in every hospital with microbiology laboratories in LMICs.

External quality assessment program for human papillomaviruses DNA testing in Thailand.

Background: Since 2020, the National Health Security Office includes the human papillomavirus DNA testing for cervical cancer screening in the government's healthcare schemes. HPV DNA testing has become primary screening in many laboratories in Thailand. External quality assurance scheme is crucial for assessment of laboratory performance. Objectives: The aim of this study was to develop a pilot program using LBC samples for the EQA of molecular methods and to review the methods used by participants to detect the presence of high risk HPV genotypes. Study design: Four pilot distributions were shipped between December 2021 and May 2023, six months apart of two panels, each consisting of five different specimens. Results: All participants achieved 100 % accuracy in correctly identifying the presence or absence of high-risk genotypes in all 5 EQA samples. The most used HPV DNA test for detecting the presence of high-risk HPV DNA was the two specific high-risk genotypes and 12 other high-risk HPV genotypes. There was an observed increase in the use of assays that could detect 14 HPV HR genotypes. It suggests expanding testing methods to include a broader range of high-risk HPV genotypes, which could improve the comprehensiveness of the testing. Conclusions: The HPV DNA testing scheme provides a standardised, homogeneous and characterised clinical specimen. These results indicate that the LBC samples are suitable for utilisation in an EQA scheme. EQA of HPV molecular screening programme is essential for monitoring the performance of laboratory networks.

Impact of Omicron variant sublineage BA.2.75 on the OnSite COVID-19 Ag Rapid Test: the applicability of rapid antigen test with universal transport media.

BACKGROUND: Rapid antigen testing (RAT) is one of the most powerful tools for SARS-CoV-2 detection. The OnSite COVID-19 Ag Rapid Test is an antigen-based, point-of-care test approved by the WHO for Emergency Use Listing. The Nucleocapsid (N) gene mutations found in the emerging Omicron sublineages lead to the question of RAT performance. OBJECTIVE: To ensure the diagnostic performance of the study RAT during rapidly mutated Omicron variants. RESULTS: We independently evaluated the performance of this assay in 1098 archived samples collected in Thailand during October 2022-February 2023, which were 798 and 300 COVID-19 real-time RT-PCR positive and negative, respectively. The assay performed with 100% sensitivity and 100% specificity using a cycle threshold (Ct) of <20 for the RT-PCR. The sensitivity decreased to 88% when using Ct <30. Most of the SARS-CoV-2 found were Omicron BA.2 (99%), harboring six known N mutations (P13L, E31del, S33del, R203K, G204R and S413R). Eight samples containing hybrid variants (XBB.1*, XBB.2 and XBJ) were detected by the study RAT. This RAT detects all Omicron sublineages known to be circulating in Thailand. CONCLUSIONS: These results confirmed the good performance of the study RAT for detecting Omicron variants and its appropriateness for individual diagnosis and for genomic surveillance.

SARS-CoV-2 Seroprevalence in Unvaccinated Adults in Thailand in November 2021.

Between the first case of COVID-19 in January 2020 and the end of 2021, Thailand experienced four waves of the epidemic. The third and fourth waves were caused by the alpha and delta strains from April 2021 to November 2021. Serosurveillance studies provide snapshots of the true scale of the outbreak, including the asymptomatic infections that could not be fully captured by a hospital-based case detection system. We aimed to investigate the distribution of SARs-CoV-2 seroprevalence in unvaccinated adults after the delta wave outbreak. From November to December 2021, we conducted a cross-sectional survey study in 12 public health areas (PHAs) across Thailand. A total of 26,717 blood samples were collected and tested for SARs-CoV-2 antibodies (anti-S IgG) using a qualitative immunoassay. The results showed that seropositive prevalence in this cohort was 1.4% (95% CI: 1.24 to 1.52). The lowest prevalence was in the northern region (PHA 1) and in central Thailand (PHA 3) at 0.4% (95% CI: 0.15 to 0.95), while the highest was in the southern region of Thailand (PHA 12) at 5.8% (95% CI: 4.48 to 7.29). This seropositive prevalence was strikingly lower than the reports from other countries. Our serosurveillance results suggest that the vaccination of unvaccinated groups should be accelerated, especially in the public health areas with the lowest seroprevalence.

External quality assessment scheme for HbA1c assays in Thailand: A 5-year experience.

Background: Thailand National External Quality Assessment Scheme (NEQAS) for HbA1c was established to evaluate the quality of HbA1c assays in Thailand in 2016. Methods: HbA1c results from participating laboratories were compared to the target value assigned by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) reference system. Results: The pass rates of participating laboratories during 2016-2020 were72-88%. The mean bias ranged between -0.19 and 0.20% of HbA1c. SD ranged from 0.30 to 1.08% of HbA1c. The overall coefficients of variation ranged from 4.46-15.66%. Conclusions: Performance evaluation using IFCC assigned values indicated that different assay methods had an effect on HbA1c results. Participation in external quality assessment programs for HbA1c analysis is essential for improving laboratory quality and benefiting patient management.

The Association of HLA-B*35 and GSTT1 Genotypes and Hepatotoxicity in Thai People Living with HIV.

Glutathione s-transferase (GST) is a family of drug-metabolizing enzymes responsible for metabolizing and detoxifying drugs and xenobiotic substances. Therefore, deletion polymorphisms of GSTs can be implicated in developing several pathological conditions, including antiretroviral drug-induced liver injury (ARVDILI). Notably, GST polymorphisms have been shown to be associated with ARVDILI risk. However, data on GST polymorphisms in the Thai population are limited. Therefore, this study investigated possible associations between GST genetic polymorphisms and ARVDILI development. A total of 362 people living with HIV (PLHIV) and 85 healthy controls from multiple centers were enrolled. GSTM1 and GSTT1 genetic polymorphisms were determined using polymerase chain reactions. In addition, HLA genotypes were determined using a sequence-based HLA typing method. After comparing GST genotypic frequencies, there was no significant difference between PLHIV and healthy volunteers. However, while observing the PLHIV group, GSTT1 wild type was significantly associated with a 2.04-fold increased risk of ARVDILI (95%CI: 1.01, 4.14; p = 0.045). Interestingly, a combination of GSTT1 wild type and HLA-B*35:05 was associated with a 2.28-fold higher risk of ARVDILI (95%CI: 1.15, 4.50; p = 0.02). Collectively, GSTT1 wild type and a combination of GSTT1 wild type plus HLA-B*35:05 were associated with susceptibility to ARVDILI in the Thai population.

The Pilot Study of Immunogenicity and Adverse Events of a COVID-19 Vaccine Regimen: Priming with Inactivated Whole SARS-CoV-2 Vaccine (CoronaVac) and Boosting with the Adenoviral Vector (ChAdOx1 nCoV-19) Vaccine.

In response to the SARS-CoV-2 Delta variant, which partially escaped the vaccine-induced immunity provided by two doses of vaccination with CoronaVac (Sinovac), the National Vaccine Committee recommended the heterologous CoronaVac-ChAdOx1 (Oxford−AstraZeneca), a prime−boost vaccine regimen. This pilot study aimed to describe the immunogenicity and adverse events of the heterologous CoronaVac-ChAdOx1 regimen, in comparison with homologous CoronaVac, and homologous ChAdOx1. Between May and August 2021, we recruited a total of 354 participants from four vaccination groups: the CoronaVac-ChAdOx1 vaccinee (n = 155), the homologous CoronaVac vaccinee (n = 32), the homologous ChAdOx1 vaccinee (n = 47), and control group of COVID-19 patients (n = 120). Immunogenicity was evaluated by measuring the level of IgG antibodies against the receptor-binding domain (anti-SRBD) of the SARS-CoV-2 spike protein S1 subunit and the level of neutralizing antibodies (NAbs) against variants of concern (VOCs) using the plaque reduction neutralization test (PRNT) and pseudovirus neutralization test (pVNT). The safety profile was recorded by interviewing at the 1-month visit after vaccination. The anti-SRBD level after the second booster dose of the CoronaVac-ChAdOx1 group at 2 weeks was higher than 4 weeks. At 4 weeks after the second booster dose, the anti-SRBD level in the CoronaVac-ChAdOx1 group was significantly higher than either homologous CoronaVac, the homologous ChAdOx1 group, and Control group (p < 0.001). In the CoronaVac-ChAdOx1 group, the PRNT50 level against the wild-type (434.5 BAU/mL) was the highest; followed by Alpha variant (80.4), Delta variant (67.4), and Beta variant (19.8). The PVNT50 level was also found to be at its highest against the wild-type (432.1); followed by Delta variants (178.3), Alpha variants (163.9), and Beta variant (42.2), respectively. The AEs in the CoronaVac-ChAdOx1 group were well tolerated and generally unremarkable. The CoronaVac-ChAdOx1 heterologous regimen induced higher immunogenicity and a tolerable safety profile. In a situation when only CoronaVac-ChAdOx1 vaccines are available, they should be considered for use in responding to the Delta variant.

Deficiency of mannose-binding lectin is a risk of Pneumocystis jirovecii pneumonia in a natural history cohort of people living with HIV/AIDS in Northern Thailand.

BACKGROUND: Mannose-binding lectin (MBL) plays a pivotal role in innate immunity; however, its impact on susceptibility to opportunistic infections (OIs) has not yet been examined in a natural history cohort of people living with HIV/AIDS. METHODS: We used archived samples to analyze the association between MBL expression types and risk of major OIs including Pneumocystis jirovecii pneumonia (PCP), cryptococcosis, talaromycosis, toxoplasmosis, and tuberculosis in a prospective cohort in Northern Thailand conducted from 1 July 2000 to 15 October 2002 before the national antiretroviral treatment programme was launched. RESULTS: Of 632 patients, PCP was diagnosed in 96 (15.2%) patients, including 45 patients with new episodes during the follow-up period (1006.5 person-years). The total history of PCP was significantly associated with low MBL expression type: high/intermediate (81/587, 13.8%), low (10/33, 30.3%) and deficient (5/12, 41.7%) (p = 0.001), whereas the history of other OIs showed no relation with any MBL expression type. Kaplan-Meier analysis (n = 569; log-rank p = 0.011) and Cox's proportional hazards model revealed that deficient genotype dramatically increased the risk of PCP, which is independent upon sex, age, CD4 count, HIV-1 viral load and hepatitis B and C status (adjusted hazard ratio 7.93, 95% confidence interval 2.19-28.67, p = 0.002). CONCLUSIONS: Deficiency of MBL expression is a strong risk factor determining the incidence of PCP but not other major OIs.

Implementation of an active case management network to identify HIV-positive infants and accelerate the initiation of antiretroviral therapy, Thailand 2015 to 2018.

INTRODUCTION: Early initiation of antiretroviral therapy (ART) can reduce HIV-related morbidity and mortality in HIV-positive infants. We implemented an Active Case Management Network to promote early ART initiation Aiming for Cure (ACC) in August 2014. We describe ACC implementation, early infant diagnosis (EID) coverage and ART initiation during August 2014 to July 2018 compared with a national EID survey during October 2007 to September 2011 (pre-ACC). METHODS: Thailand's 2014 HIV Treatment Guidelines recommend that HIV-exposed infants have HIV polymerase chain reaction (PCR) testing at birth, one month and at two to four months. Testing is done at 14 national HIV PCR laboratories. When an HIV-positive infant (HIV PCR+) is identified, PCR laboratory staff send the result to the hospital staff responsible for the infant's care and to the national laboratory case manager (CM). As part of ACC, the national laboratory CM alerts a regional CM who contacts the hospital staff caring for the infant to offer technical support with ART initiation and ART adherence. CMs enter clinical, demographic and laboratory data into the national ACC database. We analysed the ACC data from August 2014 to July 2018 to assess the ACC's impact on EID coverage, ART initiation and time-to-ART initiation. RESULTS: The uptake of EID increased from 64% (pre-ACC) to >95% in 2018 (ACC). The number of HIV-positive infants born declined from 429 cases (pre-ACC) to 267 cases (ACC). Median age at the first-positive PCR declined from 75 days (pre-ACC) to 60 days (ACC); P < 0.001. Among 429 infants diagnosed before ACC was started, 241 (56%) received ART; during ACC, 235 (88%) of 267 HIV-positive infants received ART. The median age at ART initiation declined from 282 days before ACC to 83 days during ACC (P < 0.001) and the median time from blood collection to ART initiation declined from 168 days before ACC to 23 days during ACC (P < 0.001). CONCLUSIONS: An innovative case management network (ACC) has been established in Thailand and results suggest that the network is promoting EID and early ART initiation. The ACC model, using case-managed PCR notification and follow-up, may speed ART initiation in other settings.

Impact of HLA Allele-KIR Pairs on Disease Outcome in HIV-Infected Thai Population.

BACKGROUND: Class I human leukocyte antigen (HLA) molecules contribute to HIV control through antigen presentation to both cytotoxic T lymphocytes and natural killer cells. Contribution of cytotoxic T lymphocytes to HIV clinical outcome by HLA alleles has been well studied. However, reports about the role of natural killer cells in HIV clinical outcome, particularly, about the effect of HLA-killer immunoglobulin-like receptor (KIR) pairs, remain incomplete. METHODS: The effects of HLA allele-KIR pairs on HIV clinical outcome were statistically analyzed in a Thai cohort of treatment-naive chronically infected population (n = 209). RESULTS: Five HLA allele-KIR pairs scored significantly in viral load (VL) differences. Among them, opposing effects on VL were identified among subjects expressing KIR2DL2 ligands within the HLA-C1 group: higher VL in individuals expressing HLA-B*46:01+KIR2DL2+ compared with individuals without KIR (HLA-B*46:01+KIR2DL2-) (5.0 vs 4.6 log10 copies/mL, P = 0.02), in HLA-C*01:02+KIR2DL2+ (5.0 vs 4.6 log10 copies/mL; P = 0.02), and lower VL in HLA-C*12:03+KIR2DL2+ (4.3 vs 5.6 log10 copies/mL; P = 0.01). In the longitudinal analysis of a ten-year follow-up, HLA-B*46:01+KIR2DL2+ve subjects also had a higher mortality rate compared with the subjects without that pair, independent of variables including antiretroviral treatment, as well as CD4 T-cell count, sex, and age (adjusted hazard ratio 5.9, P = 0.02). CONCLUSION: We identified several HLA allele-KIR pairs associated with clinical outcome differences including opposing effects on VL within 1 HLA group with the same KIR. Among them, HLA-B*46:01 emerged in Southeast Asia about 50,000 years ago and is now the most prevalent HLA-B allele in that area. These findings highlight that each endemic area has unique features of anti-HIV innate immunity that impact clinical outcome.

Regional Differences in the Prevalence of Major Opportunistic Infections among Antiretroviral-Naïve Human Immunodeficiency Virus Patients in Japan, Northern Thailand, Northern Vietnam, and the Philippines.

To identify regional differences in the distribution of opportunistic infections (OIs) among human immunodeficiency virus (HIV)-infected patients in Asia, the medical records of antiretroviral therapy (ART)-naïve patients who attended the following tertiary hospitals from 2003 to 2011 were reviewed: Nagoya Medical Center (NMC, Nagoya, Japan), Lampang Hospital (LPH, Lampang, northern Thailand), Bach Mai Hospital (BMH, Hanoi, northern Vietnam), and Philippine General Hospital (PGH, Manila, Philippines). Logistic regression analyses were performed to identify associations between country of origin and risk of major OIs. In total, 1,505 patients were included: NMC, N = 365; LPH, N = 442; BMH, N = 384; and PGH, N = 314. The median age was 32 years, and 73.3% of all patients were male. The median CD4 count was 200 cells/µL. Most patients at NMC and PGH were men who have sex with men. Injection drug users were most common at BMH (35.7%). Mycobacterium tuberculosis (TB) was most common at PGH (N = 75) but was rare at NMC (N = 4). Pneumocystis pneumonia (PCP) prevalence was highest at NMC (N = 74) and lowest at BMH (N = 13). Multivariable logistic regression showed increased odds of TB at PGH (adjusted odds ratio [aOR] = 42.2, 95% confidence interval [CI] = 14.6-122.1), BMH (aOR = 12.6, CI = 3.9-40.3), and LPH (aOR = 6.6, CI = 2.1-21.1) but decreased odds of PCP at BMH (aOR = 0.1, CI = 0.04-0.2) and LPH (aOR = 0.2, CI = 0.1-0.4) compared with those at NMC. The cryptococcosis risk was increased at LPH (aOR = 6.2, CI = 0.9-41.0) compared with that at NMC. Cytomegalovirus (CMV) retinitis prevalences were similar in all countries. OI prevalence remained high among ART-naïve patients in our cohort. The risks of TB, PCP, and cryptococcosis, but not CMV retinitis, differed between countries. Improved early HIV detection is warranted.

The effect of KIR2D-HLA-C receptor-ligand interactions on clinical outcome in a HIV-1 CRF01_AE-infected Thai population.

OBJECTIVE: Class I human leukocyte antigen (HLA) alleles interact with both cytotoxic T lymphocytes through their T-cell receptors, and natural killer cells through their killer immunoglobulin-like receptors (KIRs). Compared with the reported protective effect of KIR3DL1/S1-HLA-Bw4 interactions in HIV-infected patients, the effect of KIR2D-HLA-C combinations on HIV control remains unclear. Here, we investigate the effect of KIR2D-HLA-C combinations on HIV disease progression. DESIGN: We performed a cross-sectional and longitudinal analysis of a Thai HIV cohort. METHODS: Two hundred and nine HIV-1 CRF01_AE-infected, treatment-naive Thai patients (CD4 T-cell counts of >200/µl) and 104 exposed seronegatives were studied. The effect of KIR-HLA receptor-ligand combinations on viral transmission and survival rate was statistically analyzed. RESULTS: We found the following results: higher frequency of patients expressing both KIR2DL3 and HLA-C1 among infected patients compared with exposed seronegative (odds ratio 4.8, P = 0.004), higher viral load in patients expressing HLA-C1 with KIR2DL3 compared with those without this receptor-ligand combination (median 4.8 vs. 4.2 log copies/ml, P = 0.033), higher numbers of KIR2DL3-HLA-C1 interactions was associated with a higher viral load (ß = 0.13, P = 0.039 by linear regression model), and higher mortality rate in carriers of the KIR2DL3-HLA-C1 combination (adjusted hazard ratio 1.9, P = 0.012 by Cox hazard model). CONCLUSION: We have identified a deleterious effect of the KIR2DL3-HLA-C1 receptor-ligand combination on HIV clinical outcomes in a Thai cohort. Further investigation into mechanisms underlying this susceptibility may aid the understanding of the role of natural killer cells in HIV disease control and pathogenesis.

Incidence and predictors of regimen-modification from first-line antiretroviral therapy in Thailand: a cohort study.

BACKGROUND: Antiretroviral therapy markedly reduced mortality in HIV-infected individuals. However, in the previous studies, up to 50% of patients are compelled to modify their regimen in middle and low-income countries where salvage drug is still limited. This cohort study aimed to investigate the incidence and predictors of regimen modification from the first-line antiretroviral regimen in northern Thailand. METHODS: All HIV-infected patients starting antiretroviral therapy (ART) with generic drug (GPOvir®; stavudine, lamivudine and nevirapine) at a governmental hospital in northern Thailand from 2002 to 2007 were recruited. Baseline characteristics and detailed information of regimen modification until the end of 2010 were ascertained from cohort database and medical charts. As a potential genetic predictor of regimen modification, HLA B allele was determined by bead-based array hybridization (WAKFlow® HLA typing kit). We investigated predictors of the regimen modification using Cox's proportional hazard models. RESULTS: Of 979 patients, 914 were eligible for the analysis. The observed events of regimen modification was 377, corresponding to an incidence 13.8/100 person-year-observation (95% CI:12.5-15.3) over 2,728 person years (PY) follow up. The main reasons for regimen modification were adverse effects (73.5%), especially lipodystrophy (63.2%) followed by rash (17.7%). Sixty three patients (17.1%) changed the regimen due to treatment failure. 2% and 19% of patients had HLA-B*35:05 and B*4001, respectively. HLA-B*35:05 was independently associated with rash-related regimen modification (aHR 7.73, 95% CI:3.16-18.9) while female gender was associated with lipodystrophy (aHR 2.11, 95% CI:1.51-2.95). Female gender (aHR 0.54, 95% CI: 0.30-0.96), elder age (aHR 0.56, 95% CI: 0.32-0.99) and having HLA-B*40:01 (aHR 0.29, 95% CI: 0.10-0.82) were protective for treatment failure related modification. CONCLUSION: HLA-B*35:05 and female gender were strong predictors of regimen modification due to rash and lipodystrophy, respectively. Female gender, elder age, and having HLA-B*40:01 had protective effects on treatment failure-related regimen modification. This study provides further information of regimen modification for future tailored ART in Asia.

Efficacy and safety of topical Trikatu preparation in, relieving mosquito bite reactions: a randomized controlled trial.

INTRODUCTION: Trikatu is composed of dried fruits of Piper nigrum L and Piper retrofractum Vahl, and dried rhizomes of Zingiber officinale R. Although this preparation has been used to relieve pruritis, pain, and inflammation for a long time, there is no clinical evidence to confirm its efficacy and safety. Therefore, we performed a double-blind, within person-randomized controlled study of 30 healthy volunteers to determine efficacy and safety of topical Trikatu on mosquito bite reactions. METHODS: All subjects were bitten by Aedes aegypti laboratory mosquitoes on their forearms and they were randomly assigned arms to apply either Trikatu or reference product on the mosquito bite papule. The main outcome was the difference of papule size reduction at 30 min, measured by a caliper, between the Trikatu and reference arms. Pruritis, redness, pain, and patient satisfaction were assessed at 15, 30, 60, 180, and 360 min as secondary outcomes. RESULTS: There were no significant differences between treatment and reference arms on any outcome at any time of measurement. CONCLUSION: Trikatu did not show additional effects for relieving mosquito bite reaction as compared with the reference product containing camphor, menthol, and eucalyptus. For further study, it is very important to consider a proper selection of subjects, comparator product, and concentration of extract when Trikatu preparation is investigated.

HLA-B*35: 05 is a protective allele with a unique structure among HIV-1 CRF01_AE-infected Thais, in whom the B*57 frequency is low.

OBJECTIVE: To identify protective human leukocyte antigen (HLA) alleles in an HIV-infected south-east Asian population, in whom HLA-B*57 prevalence is lower than other ethnic groups, and HIV-1 CRF01_AE is the dominant circulating subtype. DESIGN: Cross-sectional study of Thai patients with chronic HIV infection. METHODS: Five hundred and fifty-seven HIV-1 CRF01_AE-infected Thais were recruited. Their HLA type and viral load were determined to statistically analyze the association of each allele in viral control. In-silico molecular dynamics was also used to evaluate the effect of HLA structure variants on epitope binding. RESULTS: HLA-B*35:05 was identified as the most protective allele (P=0.003, q=0.17), along with HLA-B*57:01 (P=0.044, q=0.31). Structurally, HLA-B*35:05 belonged to the HLA-B*35-PY group of HLA-B*35 alleles; however, unlike the other HLA-B*35 alleles that carry Arg (R) at residue 97, it has unique sequences at T94, L95, and S97, located within the peptide-binding groove. Analysis of the three-dimensional HLA structure and molecular dynamics indicates that S97 in HLA-B*35:05 leads to less flexibility in the groove, and shorter distances between the α-helixes compared with the disease-susceptible HLA-B*35-PY allele, HLA-B*35:01. CONCLUSION: These data indicate the existence of a protective effect of HLA-B*57 across ethnic groups and highlight HLA-B*35:05 as an allele uniquely protective in subtype CRF01_AE-infected Thais. The divergence of HLA-B*35:05 from conventional HLA-B*35-PY structural sequences at the peptide-binding groove is consistent with previous studies that have identified HLA residue 97 as strongly influential in shaping HLA impact on immune control of HIV, and that a more restricted peptide-binding motif may be associated with improved control.

Changing burden of HIV/AIDS to clinical settings in Northern Thailand over 15 years.

We conducted a hospital-based descriptive study to describe the changing pattern of patient numbers, characteristics, and mortality rates among human immunodeficiency virus (HIV)-infected patients in northern Thailand over 15 years. The survival status on October 31, 2010 of all HIV-infected adults who attended an HIV center in a government hospital between 1995 and 2010 was ascertained. In total, 3,706 patients were registered, 2,118 (57.2%) of which were male. The survival status of 3,439 patients (92.9%) was available. In addition, 1,543 deaths were identified out of 12,858 person-year-observations (PYO) resulting in a mortality rate of 12.4 deaths/100 PYO (95% confidence interval [CI], 11.3-13.0). An initial decline in mortality rates was observed prior to 1999, probably because of an increase in the proportion of less symptomatic patients. After the introduction of the national highly active antiretroviral therapy (HAART) program, a profound decline in mortality rates was observed, reaching 2.0 deaths/100 PYO (95% CI, 1.4-2.9) in 2010. Simultaneously, the number of patients on follow-up increased by nearly fourfold. Although HAART has drastically improved the survival of HIV-infected patients, the number of patients receiving therapy at this HIV clinic has substantially increased. While referral of HIV patients to general physicians' care should be urged, we cannot overemphasize the importance of preventing new HIV infections.

Impact of the National Access to Antiretroviral Program on the incidence of opportunistic infections in Thailand.

The National Access to Antiretroviral Program caused a decline in HIV mortality in Thailand, but its impact on opportunistic infections (OI) remains unknown. The aim of this study was to compare the incidence of different OIs before and after the initiation of highly active antiretroviral therapy (HAART). Data from a prospective cohort at a hospital in northern Thailand were analysed. In total, 704 patients enrolled from July 2000 to October 2002 and not on HAART were followed up until October 2004. In addition, 409 patients who started HAART between April 2002 and January 2004 were followed up for 24 months. The impact of HAART on OIs was analysed using Cox proportional hazard models. HAART was associated with a strong reduction in OIs. The reduction appeared to vary by type: tuberculosis (TB), adjusted hazard ratio (AHR) = 0.2 (95% CI 0.1-0.5); pneumocystis pneumonia (PCP), AHR = 0.03 (95% CI 0.007-0.1); cryptococcal meningitis, AHR = 0.2 (95% CI 0.1-0.5); and penicilliosis, AHR = 0.1 (95% CI 0.06-0.3). In conclusion, HAART was very effective in reducing OIs, especially PCP. TB and cryptococcal meningitis remained frequent in the early phase of antiretroviral drug therapy. More attention to prophylaxis as well as earlier diagnosis and starting treatment for these OIs is recommended.

TIM1 haplotype may control the disease progression to AIDS in a HIV-1-infected female cohort in Thailand.

OBJECTIVE: To investigate association of TIM1 sequence variations with HIV/AIDS progression. INTRODUCTION: : HIV-1 infected individuals have wide variations in disease progression including AIDS. T cell immunoglobulin and mucin 1 (TIM1) is a cell surface protein involved in the regulation of Th1/Th2 immune response. MATERIALS AND METHODS: We sequenced the highly polymorphic exon 4 of TIM1 from 246 individuals of HIV-1 infected Thai female cohort to determine their TIM1 haplotypes. Associations of TIM1 haplotypes with baseline clinical data (sero-status, plasma viral load, CD4 cell count, and symptomatic AIDS) and survival status during 3 years of follow-up were evaluated. RESULTS: Seven TIM1 haplotypes, D3-A, D4, D3-C, D1, W-A, W-C, and D3-C*, were found in the cohort. Patients possessing the D3-A haplotype showed trends towards higher CD4 cell count (P = 0.06) and lower proportion of AIDS-related symptoms (P = 0.022) than the other patients at the baseline. Kaplan-Meier analysis demonstrated that patients carrying the D3-A haplotype had a better survival rates (P = 0.019) than the others. D3-A haplotypes was tightly linked to the lower expression levels of TIM1. CONCLUSION: TIM1 D3-A haplotype is associated with the delay of disease progression to AIDS in the HIV-1 infected Thai females.

Drug-resistant mutation patterns in CRF01_AE cases that failed d4T+3TC+nevirapine fixed-dosed, combination treatment: Follow-up study from the Lampang cohort.

HIV/AIDS patients are treated in Thailand's national antiretroviral treatment (ART) program with a generic combination tablet of stavudine, lamivudine, and nevirapine (GPOvir). To determine GPOvir-resistant mutations, HIV-1 sequences of 59 GPOvir-failure cases from the Lampang cohort were compared with sequences from 76 randomly selected ART-naïve cases. The GPOvir-failure cases had not only known stavudine-, lamivudine- and nevirapine-resistant mutations, but also V118I, G196E, and H221Y. Among the 59 GPOvir-failure cases, 29 were ART-naïve prior to GPOvir (naïve group), and 30 had previous ART (exposed group). To clarify the effect of previous ART in drug-resistant acquisition pathways, naïve and exposed groups were compared. The exposed group had predominantly thymidine analogue-related mutations, whereas the naïve group had a higher prevalence of Q151M and K103N mutations. M184V lamivudine resistance was most frequent in both naïve and exposed groups. To identify which mutations in CRF01_AE pol were polymorphisms, the connection and RNase domains were also analyzed. CRF01_AE-specific polymorphisms were found in 19 residues, and GPOvir-failure cases had significantly higher frequency of N348I, E399D, P537S, and I542M. Our results expand identification of mutations in CRF01_AE pol that are polymorphisms by also analyzing the connection and RNase H domains.