Morphological indices and patterns of acid-fast bacilli from multiple sites were not correlated with IL-10, PGE2, and IL-35 levels in multibacillary leprosy patients

Abstract

Multibacillary leprosy is characterized by a high bacterial load and a tolerogenic immune profile involving interleukin-10 (IL-10), prostaglandin E2 (PGE2), and interleukin-35 (IL-35). Previous studies relied solely on the aggregate bacterial index, without accounting for bacillary distribution across body sites or viability, reflected in the morphological index. This study analyzed relationships between the morphological index and acid-fast bacilli (AFB) patterns at six sites and serum IL-10, PGE2, and IL-35 levels in multibacillary leprosy patients in Banyuasin Regency, South Sumatra, using a cross-sectional design. The morphological index and AFB grade at both ears, hands, and feet were examined via skin scraping. IL-10 and PGE2 levels were measured in 30 patients, and IL-35 levels in 29 patients. Five bacteriological metrics were correlated with the three immune markers using Spearman's correlation, with P values corrected using the Benjamini-Hochberg method. Of the fifteen pairs tested, none were significant after correction (corrected P 0.96-0.97). The strongest correlation was between the number of positive smear sites and PGE2 (rho -0.27, P = 0.16), with a confidence interval crossing zero. The morphological index and multisite AFB patterns were not associated with IL-10, PGE2, or IL-35. Larger studies are needed to confirm these associations.