Kalayanee Atamasirikul

The role of serum cryptococcal antigen screening for the early diagnosis of cryptococcosis in HIV-infected patients with different ranges of CD4 cell counts

OBJECTIVE To determine the role of serum cryptococcal antigen (SCA) for the screening of cryptococcosis in HIV-infected patients with different ranges of CD4 cell counts. METHODS A retrospective cohort study was conducted in antiretroviral-naïve HIV-infected patients who had no symptom and had been screened with SCA in a tertiary-care hospital. Prevalence of positive SCA at different ranges of CD4 cell counts, risk factor of positive SCA, and incidence of cryptococcosis during one-year follow-up period after negative SCA were determined. RESULTS There were 131 patients with a mean age of 38.5 years; 61.8% were male. Median (range) CD4 was 62 (3-590) cells/mm(3). The overall prevalence of positive SCA was 9.2%. This prevalence in patients with CD4 < 100, 100-199, and >or=200 cells/mm(3) were 12.9%, 3.6%, and 0%, respectively (P = 0.041). In multivariate analysis, CD4 < 100 cells/mm(3) was associated with positive SCA (OR = 6.69; 95% CI, 1.03-23.56). Four (33.3%) of 12 patients with positive SCA had cryptococcosis whereas one (0.8%) of 119 patients with negative SCA developed meningitis at one-year follow-up. CONCLUSIONS SCA screening has a substantial role for the early detection of cryptococcal infection in HIV-infected patients with low CD4 cell counts. Routine screening with SCA should be performed in patients with CD4 < 100 cells/mm(3).

Clinical presentations of newly diagnosed HIV-infected patients at a university hospital in Bangkok, Thailand.

Background: Epidemiology and clinical features of newly diagnosed HIV-infected patients vary and depend on period of time and geographical area. Methods: A retrospective review was conducted in adults with positive HIV antibody testing between January and December 2006 at a university hospital setting. Results: Prevalence of HIV infection was 1.0%. There were 221 patients with a median age of 35.5 (range, 15.8-72.3) years, and 57% were males. The most common risk of HIV acquisition was heterosexual (63.8%). The most common reason for HIV testing was preoperative screening (41.2%). Of all, 52.9%, 37.1%, and 10% were diagnosed as AIDS, asymptomatic, and symptomatic patients, respectively. Median CD4 count at HIV diagnosis was 260 (range, 6-1284) cells/mm3. AIDS-defining illnesses were found in 35.7%. Overall mortality rate was 1.8%. Conclusions: More than half of newly diagnosed HIV-infected patients have advanced HIV disease and are unaware of their HIV status. These results reflect inadequate education of HIV risks and voluntary HIV testing in Thailand.

Late and Low Compliance with Hepatitis B Serology Screening Among HIV-Infected Patients in a Resource-Limited Setting: An Issue to Improve HIV Care

Although hepatitis B serology screening has been recommended for HIV care, it has not been routinely performed. We aimed to assess compliance and timing of hepatitis B serology screening among HIV-infected patients in a resource-limited setting. A cross-sectional study was conducted in Thailand. Compliance, timing of hepatitis B serology screening, and factors associated with no HBsAg screening were determined. A total of 416 HIV-infected patients with 61% males were enrolled. Median (range) age at HIV diagnosis was 34 (16-75) years and 92% had heterosexual risk. Proportion of HBsAg screening and prevalence of positive HBsAg were 69.2% and 9.0%, respectively. There was no difference in the proportion of no HBsAg screening during the period 1990-2008 (p = 0.865). Proportion of anti-HBs and anti-HBc screening were 40.9% and 21.2%, respectively. HBsAg was screened before or on the day of anti-HIV testing in 9.1% and before antiretroviral therapy (ART) initiation in 27.2%. By Kaplan-Meier analysis, median time from anti-HIV testing to HBsAg screening was 55.9 (95% confidence interval [CI] 43.9, 68.3) months. By multivariate logistic regression, duration of HIV infection (odds ratio [OR] 1.14; 95% CI 1.07, 1.21), no anti-HBs screening (OR 1.65; 95% CI 1.4-2.63), and no anti-HCV screening (OR 2.60; 95% CI 1.62, 4.17) were associated with no HBsAg screening before ART initiation. In conclusion, compliance with hepatitis B serology screening was relatively low and late. Educational program regarding hepatitis B serology screening, identification of barriers, and interventions to eliminate these barriers in resource-limited settings are crucial to improve HIV care.

Semiquantitative human immunodeficiency virus antibody tests in diagnosis of vertical infection.

OBJECTIVE This study evaluated the roles of semiquantitative anti-HIV antibody tests for early diagnosis of vertical HIV-1 infection in infants. METHODS The study included 0- to 18-month-old children of HIV-1-infected mothers. They were regularly followed up, and blood was obtained for semiquantitative anti-HIV tests using a particle agglutination (PA) test and a microparticle enzyme immunoassay (MEIA). RESULTS One hundred forty-six children of HIV-1-infected mothers, including 104 infected and 42 uninfected infants, were studied. Using anti-HIV titer of < or = 1:100 by PA and optical values of < or = -3 by MEIA for diagnosis of not being infected, approximately 69 and 53% of the uninfected cases at age 7 to 8 months, 76 and 67% at age 9 months and 100% at age 12 months could be diagnosed. By comparison with the diagnosis by qualitative tests the figures were 16%, 8 and 11%, 70 and 74% at the same ages. All asymptomatic HIV-infected cases had persistently high PA titers and MEIA values of at least 1:5000 and 6, respectively, but 7 cases with AIDS-related manifestation at the time of tests had low anti-HIV titers. One severely ill, HIV-infected infant had a transient negative anti-HIV test at the age of 7 months. Two asymptomatic infected children, who had been breast-fed, had transient decrease in anti-HIV titers after the age of 6 months, and transient seroreversion occurred in one. CONCLUSION. Semiquantitative anti-HIV tests between the age of 6 to 12 months were very useful in diagnosis of HIV-1 infection in infants born of HIV-1-infected mothers. Interpretation must be accompanied by information about AIDS-related manifestation and history of breast-feeding.

C677T methylenetetrahydrofolate reductase and plasma homocysteine levels among Thai vegans and omnivores.

Hyperhomocysteinemia among vegetarians and vegans is caused mostly by vitamin B12 deficiency. A C-to-T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene results in a thermolabile MTHFR, which may affect homocysteine (Hcy) levels. The importance of this gene mutation among populations depends on the T allele frequency. Blood Hcy, vitamin B12, folate, vitamin B6, and MTHFR C677T mutation status were determined in 109 vegans and 86 omnivores aged 30 - 50 years. The vegans had significantly higher Hcy levels than the omnivores, geometric means (95 % CI) 19.2 (17.0 - 21.7) µmol/L vs. 8.53 (8.12 - 8.95) µmol/L, p < 0.001. A C-to-T mutation in the vegans increased plasma Hcy, albeit insignificantly; geometric means 18.2 µmol/L, 20.4 µmol/L, and 30.0 µmol/L respectively in CC, CT, and TT MTHFR genotypes. There was also a significant decrease in serum folate; geometric means 12.1 ng/mL, 9.33 ng/mL, and 7.20 ng/mL respectively, in the CC, CT, and TT mutants, p = 0.006, and particularly, in the TT mutant compared with the CC wild type, 7.20 ng/mL vs. 12.1 ng/mL, p = 0.023. These findings were not seen in the omnivores. It was concluded that hyperhomocysteinemia is prevalent among Thai vegans due to vitamin B12 deficiency. C-to-T MTHFR mutation contributes only modestly to the hyperhomocysteinemia.