International Journal of Science and Research (IJSR) ISSN: 2319-7064 ResearchGate Impact Factor (2018): 0.28 | SJIF (2018): 7.426 Volume 9 Issue 1, January 2020 www.ijsr.net Licensed Under Creative Commons Attribution CC BY Histopathological Spectrum of Cutaneous Granulomatous Lesions Utkarsh N Pattar 1 , Hilda Fernandes 2 , Vasudev Prabhu 3 1, 3 Post Graduate Resident, Department of Pathology, Father Muller Medical College, Mangalore, Karnataka, India 2 Professor and Ex Head, Department of Pathology, Father Muller Medical College, Mangalore, Karnataka, India (Correspondence) Abstract: Background : Cutaneous granulomatous lesions often pose a diagnostic challenge to the pathologists because many of the lesions can clinically as well as morphologically mimick each other. This study was carried out in order to determine the morphology and relative frequency of these lesions and to compare the findings with previously done studies. Materials and methods : A retrospective study of the skin biopsies received in the Department of pathology, FMMC, Mangalore was carried out, and cases of cutaneous granulomatous lesions on histopathological examination and special stains were reviewed. Results : Out of the 84 cases included in the study, male preponderance was noted (71.43%), Maximum number of cases were observed in the patients of age group in the third and sixth decades. Tuberculoid granulomas were the most common type of granulomas (65.48%). Leprosy was the commonest cutaneous granulomatous lesion in the study. Conclusion : In our study, Leprosy was the most common granulomatous skin lesion. Histopathological examination with H and E, aided by special stains is the most valuable tool in the diagnosis, management and prognosis of these lesions. Keywords: Cutaneous granulomatous lesions, Leprosy, Tuberculoid granulomas 1. Introduction The term “granulomatous” was expressed initially by Virchow to describe a tumour-like mass or nodule of granulation tissue. 1 Granulomatous inflammation is a distinctive pattern of chronic inflammation characterised by formation of circumscribed microscopic aggregates of activated macrophages forming epithelioid histiocytes with variable number of admixed multinucleated giant cells and a collar of lymphocytes, known as granulomas. 2 These are encountered in a certain specific pathological states caused by a variety of offending agents which are often difficult to eradicate, being non degradable by both neutrophils and non active macrophages. 3 The actions of polymorphonuclear leucocytes, non-activated macrophages and chemical mediators which are associated with the tissue injury are insufficient to completely digest and eradicate the offending agents. For such degradation an action of transformed/modified macrophages is required which are formed in response to cell mediated immunity. 4 The CD4+T cells secrete various mediators such as IL2, IF alpha, TNF and lymphotoxin for the transformation of the macrophages into epithelioid cells and giant cells, which are the components of granulomas. 5 This is characterised by persistent inflammation, tissue injury, attempted repair by scarring and immune response, mediated by a variety of cytokines secreted by macrophages and T lymphocytes. Granulomatous lesions can be classified into six types based on the type of participating inflammatory cells, and associated changes i.e 1)Tuberculoid, 2)Sarcoid 3) Necrobiotic 4)Suppurative 5) Foreign body 6) Histoid There is a high prevalence of cutaneous granulomatous lesions in a developing country like India with leprosy and tuberculosis being the most common causes. However, the frequency of these infections across different regions is variable. 6 Tuberculosis is the prototype of granulomatous inflammation and should always be ruled out as a cause, whenever granulomas are identified. Granulomatous inflammations are a common and intriguing problem. The arrival at a proper diagnosis is mandatory, so that the appropriate treatment can be meted out. 7 Good clinical history, a close histological examination and a clinicopathological correlation is essential in making a final diagnosis. By combining all the available information, one should be able to arrive at a reasonable differential diagnosis on which to proceed. However, in a minority of the cases, it will not be possible to make a definitive diagnosis, even with all the clinical information being available. Special stains may also be required to reach a diagnosis. In a small percentage of cases, no definitive diagnosis can be given, other than that of granulomatous inflammation. The morphologic pattern in the various cutaneous granulomatous diseases may be sufficiently different to allow reasonable accurate diagnosis by the pathologist. Very few comparative studies have been carried out to determine the frequency and types of different granulomatous lesions of the skin. This study was undertaken with the aim of classifying cutaneous granulomatous dermatoses based on its cause, to determine the frequency and pattern of these lesions and to study their clinical and histopathological spectrum. Paper ID: ART20201557 DOI: 10.21275/ART20201557 632