Elevated anti-tuberculous glycolipid antibody titres in healthy adults and tuberculosis patients in Thailand.

OBJECTIVE: To evaluate immunoglobulin G (IgG) and immunoglobulin A (IgA) responses to tuberculous-glycolipid antigen (TBGL-IgG and -IgA) in pulmonary tuberculosis (TB) patients and healthy controls in Thailand. DESIGN: Anti-TBGL antibody titres and other TB related markers were measured in the serum samples of 24 adults with pulmonary TB (PTB), 28 healthy adults (HA), 23 children with TB (CTB) and 24 healthy children (HC). RESULT: Both TBGL-IgG and -IgA titres were significantly higher only in adult PTB cases compared to controls (P 0.05). Serum IgG and IgA levels were not correlated with TBGL-IgG or -IgA levels (P > 0.05). KL-6 and leptin levels were normal and were not different between HA+ and HA-, indicating absence of active TB in HAs. CONCLUSION: Enhanced TBGL-IgG+IgA responses in HAs could indicate latent TB infection. Careful follow-up studies in HAs could clarify the significance of elevated TBGL antibodies as early disease markers.