Mast cells in histoid lepromatous lesions.

Ten patients with histoid lesions among the lepromatous leprosy cases, of both sexes in the age group of 35-65 years, were included in this study. Skin biopsy from the nodule with surrounding healthy skin of histoid lesion was taken. The biopsies were fixed in Susa solution and processed for light microscopy. 5-7 mu thick sections were cut and stained with haematoxylin and eosin, Toluidine blue and Fite Faraco. Observations were made on the dermis to locate the mast cells and bacilli. Proliferation of mast cells and their degranulation were seen in the histoid nodule as compared to surrounding normal healthy skin where the cells were mainly intact. The study further investigates the role of mast cells in the histopathogenesis of the disease.