Background: Alterations in serum lipids, especially cholesterol, are known to occur in bacterial infections like tuberculosis. However, relationship between serum levels of cholesterol and extent of tuberculosis and smear positivity has not been studied in detail.
Objective: To determine the levels of serum cholesterol, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) in patients of pulmonary tuberculosis and analyze its correlation with severity of disease and sputum positivity.
Methods: Fifty patients of pulmonary tuberculosis were included in the study. Levels of serum cholesterol, LDL, and HDL were determined in this group and compared in the different subjects, depending on the radiological extent and sputum positivity.
Results: Levels of serum cholesterol, HDL, and LDL were found to be significantly lower in smear-positive group when compared with the smear-negative group, the values being cholesterol (141.29 ± 26.49 vs 177.5 ± 33.0, P < 0.05), HDL (31.45 ± 3.5 vs 37.32 ± 4.27, P < 0.05) and LDL (101.52 ± 15.06 vs 119.37 ± 12.69, P < 0.05). Similarly, the levels of these lipids were found to be significantly lower in the advanced tuberculosis(stage III) group as compared with stages II and I, the values being cholesterol (133.16 ± 22.59 vs 159.36 ± 16.94 vs 190.79 ± 29.02, P < 0.05), HDL (31.36 ± 3.89 vs 34.36 ± 4.2 vs 37.29 ± 4.29, P < 0.05), and LDL (97.60 ± 13.92 vs 119.36 ± 4.11 vs 122.64 ± 13.86, P < 0.05).
Discussion: Serum cholesterol, HDL, and LDL levels can be used as an indirect marker of severity of tuberculosis, with lower levels indicating advanced disease. This may have implications in tuberculosis control programs, especially in countries with high prevalence.