Levels of tumour necrosis factor-alpha and IL-1alpha in newly diagnosed and multidrug resistant tuberculosis

Abstract

Background: The pro-inflammatory cytokines tumour necrosis factor (TNF)-alpha and IL-1alpha play key roles in host defence against tuberculosis (TB) but there is little knowledge of their levels in multidrug resistant TB (MDR-TB). The aim of the present study was to investigate the levels of TNF-alpha and IL-1alpha and their relationship with the levels of T helper (CD4+), T suppressor (CD8+) and total lymphocytes (CD45+) in newly diagnosed TB (N-TB) and MDR-TB.

Methodology: This study assessed 19 N-TB patients (M/F : 17/2) and 11 MDR-TB patients (M/F : 10/1). Serum TNF-alpha and IL-1alpha were assessed by ELISA. Lymphocyte expression of CD45, CD4, CD8, CD3, CD23, CD19 and CD95 were determined by flow cytometry.

Results: The levels of TNF-alpha, IL-1alpha, and CD4, CD4/CD8, CD45, CD19, CD23 and CD95 positive lymphocytes were lower in MDR-TB than in N-TB patients (P < 0.05). Statistically, there was a positive correlation between TNF-alpha and IL-1alpha (r = 0.92) for both MDR-TB and N-TB. For both groups, both TNF-alpha and IL-1alpha correlated with CD4+ lymphocytes (r = 0.48). TNF-alpha and IL-1alpha showed negative correlations with CD8+ lymphocytes (r = -0.81, r = -0.73) (P < 0.01) in MDR-TB patients.

Conclusion: The lower levels of cytokines and numbers of T helper lymphocytes in MDR-TB compared with N-TB implies that the immune profiles of the two groups are different, and may be important in the natural history of the disease.