T-Lymphocyte subpopulation in tuberculosis

Tuberculosis is associated with both qualitative and quantitative defects in the cell \nmediated immune response. The changes that occur in the lymphocyte profile in blood in children \nwith tuberculosis are not well understood. Design: Prospective study. Setting: Referral hospitals. \nMethods: Lymphocyte subpopulations were determined by flow cytometry in 17 healthy tuberculin \npositive children, in 22 children with newly diagnosed pulmonary tuberculosis and in 8 of these \nchildren after antituberculosis therapy, Results: Absolute numbers and percentages of CD3+ and \nCD4+ T cells were reduced in children with tuberculosis, compared to controls. CD4+ counts \nincreased significantly following antituberculosis treatment, compared to baseline values. In contrast, \nthe proportion of T cells expressing the gd T cell receptor was similar in tuberculosis patients and \ncontrots. Conclusion: Children with tuberculosis have a systemic decrease in the proportion and \nnumber of CD3+ and CD4+ T cells which reverses during therapy.