Mast Cells in Non-neoplastic Skin Lesions.

ABSTRACT

Background: Mast cells are found in tissues throughout body, particularly in proximity to surfaces that interface with the external environment. They are found at all levels of dermis, where they are grouped around blood vessels, nerves and appendages. Increase in mast cell number have been reported in various cutaneous diseases. Aims: We aim to identify and analyse the morphological aspects of distribution of mast cells and their value in non-neoplastic skin lesions. Material and Methods: Ninety seven biopsies of various skin lesions were studied for mast cells by Toluidine Blue at pH 3.9. Result: All the skin lesions showed significant increase in mast cell number. Psoriasis showed maximum number of mast cells (127/mm2) followed by Lichen planus (108/mm2). Among the cases of cutaneous bacterial infections, mast cells were maximum in leprosy cases (99/mm2) and lowest in cutaneous tuberculosis. A comparative decrease in number of mast cells was seen from lepromatous leprosy to tuberculoid leprosy. A wide range of morphological alterations of mast cells were observed in these skin lesions. Psoriasis and bullous pemphigoid cases showed maximum spindle cell morphology. Conclusion: Tissue mast cell number, distribution and morphology vary in different skin lesions depending on the degree of mast cell activation. This may have a bearing on diagnosis and management.