Serum mannan-binding lectin in patients with pulmonary tuberculosis: Its lack of a relationship to the disease and response to treatment.

Background: Lectin pathway mediates complement activation, which is activated by many microorganisms. This study aimed at determining the serum levels of mannose-binding lectin (MBL) in patients with pulmonary tuberculosis, assessing its relationship to antiuberculosis treatment response, and comparing them with a control group. Methods: This cross-sectional study was conducted on patients with pulmonary tuberculosis during 2012 and 2013 in South West of Iran. PPD-ST-negative individuals were selected as controls from healthy relatives of patients. Serum MBL levels were measured using ELISA kit (Human MBL HK323, Hycultbiotech Company, Netherlands). All patients were followed- up for response to treatment. We applied Mann-Whitney and Fisher's exact tests and used SPSS Version 17 software for statistical analysis. Results: The study included 62 patients as the case group and 63 noninfected TB patients as the control group. The MBL (ng/mL) in patients with pulmonary tuberculosis (median = 1012) was significantly (p= 0.037) higher than that of the control group (median= 296.2). No significant difference was found in the MBL level (ng/mL) between patients with response to antituberculosis treatment (median= 1012) and patients with treatment failure (median= 798.9) (p= 0.84). Conclusion: MBL may be involved in the pathogenesis of tuberculosis and in the low values that are protective against tuberculosis, and it seems that it has no effect on the antituberculosis treatment response.