CD4+ cell counts in patients with different clinical manifestations of tuberculosis

Abstract

Tuberculosis is the prototype of infections that require a cellular immune response for their control. It has been shown that CD4+ T-lymphocytes are most important in the protective response against Mycobacterium tuberculosis. CD8+ T-lymphocytes are also important for effective T-cell immune response. This study compares CD4+ and CD8+ baseline values in patients with different manifestations of tuberculosis. CD4+ and CD8+ in three groups of patients with tuberculosis (pulmonary, lymphadenitis, meningitis/milliary involvement) and a group of healthy volunteers were enumerated using flowcytometry. Twenty-six patients with pulmonary tuberculosis, 10 with adenitis, 16 with meningitis or milliary tuberculosis and 16 healthy volunteers entered the study. Mean CD4 in meningitis/milliary group was significantly lower than all other groups (p<0.05). Mean CD4 counts of patients with pulmonary tuberculosis was also significantly lower than control group (p=0.01). Mean CD8 in meningitis/milliary group was significantly lower than control group (p=0.02). No relation was found between results of TSTs and CD4 values in three groups. CD4 depletion is an expectable phenomenon in patients with tuberculosis. This study shows that patients with more severe form of disease had the lowest number of both CD4 and CD8 cells which can be a sign of suppressed cellular immunity in these patients. © 2008 by The Brazilian Journal of Infectious Diseases and Contexto Publishing. All rights reserved.