Establishment of T-lymphocyte subset reference intervals in a healthy adult population in Chennai, India.

Estimation of CD4+ T-lymphocytes continues to be an important aspect for monitoring HIV disease progression and response to antiretroviral therapy. Most of the diagnostic laboratories often rely on western text books for CD4+ T-lymphocyte reference values, which could, often be unreliable for usage in local settings. Therefore, we attempted to establish the reference values for T-lymphocyte subsets among healthy adults in a cross-sectional study carried out at the YRG Centre for AIDS Research and Education (YRG CARE) in Chennai, south India, in 213 (84 female and 129 male) healthy, HIV-1/2 seronegative adults as volunteers. Whole blood specimens were processed for CD4+, CD8+ T-lymphocyte estimation and haematological parameters. The established range of CD4+ T-lymphocyte counts for men and women were 383-1347 cells/microl (mean 865 and median 845 cells/microl) and 448-1593 cells/microl (mean 1021 and median 954 cells/microl), respectively. Women had significantly higher absolute CD4+ Tlymphocyte counts (P<0.001) and CD4+:CD8+ T-lymphocyte ratio as compared to men. The established normal range of CD4+ T-lymphocyte % was 21-59 (mean 40.2 and median 40.1). The influence of age was not observed in any of the parameters except CD4+/CD8+ T-lymphocyte ratio with the >45 yr age group. Further studies with greater sample size may be required to define the staging of HIV disease in relation to the normal CD4 T-lymphocyte count in the general population.

Colonization of mycoplasma in the upper respiratory tract of AIDS patients with pulmonary symptoms in Chennai, India.

BACKGROUND & OBJECTIVE: Mycoplasmas have been implicated in causing minor to severe respiratory infections in man. Mycoplasmas are considered to act as cofactors in patients with AIDS. A preliminary study was conducted to isolate mycoplasmas from sputum specimens of AIDS patients and non-HIV patients with underlying pulmonary symptoms and signs. METHODS: A total of 130 sputum samples (100 from AIDS patients and 30 from non-HIV) were cultured on standard pleuropneumonia-like organisms (PPLO) glucose agar up to 3 wk. The plates were examined for the presence of fried-egg colonies characteristic of Mycoplasma. Subsequently the plates were stained using Diene's stain. Sputum specimens from the AIDS patients were also screened for other bacterial pathogens. RESULTS: Mycoplasmas were detected from 36 (36%) of the AIDS patients and only 5 (16.6%) of the non HIV control individuals with underlying pulmonary symptoms. Data on the detection rates of other microorganisms from the AIDS cases were also analysed. INTERPRETATION & CONCLUSION: This preliminary study provided supportive evidence that mycoplasma colonized in upper respiratory tract of individuals with AIDS to a larger extent than that of the non HIV subjects with pulmonary symptoms. Further studies need to be done to characterize mycoplasma isolates to species level.