A Histopathological Study of Granulomatous Inflammation

Abstract

Granulomatous inflammation is a distinctive pattern of chronic inflammation that is encountered in a limited number of infectious and non-infectious conditions. Recognisation of granulomatous pattern and finding the etiology in a biopsy specimen is very important for specific treatment and outcome of the disease. We aimed at finding the etiology of all granulomatous lesions on tissue biopsy sent for histopathogical examination. A study was done at K S Hegde Medical Academy of Nitte University, Mangalore from January 2009 to December 2010. All the cases which were diagnosed as granulomas on Hematoxylin and Eosin stained sections were selected. Special stains like Ziehl-Neelsen stain, Gomori's Methenamine silver, PAS, Fite Faraco were done whenever required. We encountered 275 granulomatous lesions in our study. The most common sites were skin and subcutaneous tissue, lymph nodes, bones and joints. The commonest cause of granulomas was tuberculosis, followed by leprosy, foreign body granulomas, fungal infections, rhinoscleroma, parasites, tumor granulomas and actinomycosis. The morphological features and special staining helped us to find the specific etiology of granulomas in 253 cases whereas it could not be determined in 22 cases even after special stains. Thus we conclude that histopathological examination of granulomatous lesions helped us to find the exact etiology of granulomas in 92 % of cases. The correlation of histopathology with polymerase chain reaction (PCR) serological tests and culture correlation would have helped to find the specific etiology in the remainder of cases.

Granulomatous inflammation: A histopathological study

“…Similar to this study, epithelioid type granuloma was most common type in other studies. 6,7 However, in contrast to this study, the second most common is either foreign body type or histiocytic type in these studies.…”

“…However, the second most common cause is fungal in this study, whereas it is leprosy in study of Pawale JS et al 7 and Permi HS et al 6 . Rare causes of granulomatous lesion in this study were chalazion, BCG-instillation, tumor-associated, leishmaniasis, Crohn's Adhikari RC et al ZN stain demonstrated acid fast bacilli only in 11.11% cases in this study, whereas it was 20.74% in a study of Permi HS et al, 22.62% in a study of Pawale JS et al and 71% in a study of Krishnaswamy H et al [6][7][8] The low sensitivity of ZN stain may be due to technical reason. The most common fungal infection is aspergillosis, which is comparable to other studies.…”

“…In this study, granulomatous lesions were common in 3 rd decade of life with slight male predominance and this finding corresponds to the finding of other studies. 6,7 The commonest site was lymph node, followed by skin & subcutis, bone & joints, respiratory system and gastro-intestinal tract. In a study of Permi HS et al 6 the most common site of granulomatous lesion was skin & subcutis.…”

“…6,7 The commonest site was lymph node, followed by skin & subcutis, bone & joints, respiratory system and gastro-intestinal tract. In a study of Permi HS et al 6 the most common site of granulomatous lesion was skin & subcutis.…”

“…In a study of Permi HS et al, granulomas were seen in squamous cell carcinoma of skin, infiltrating ductal carcinoma of breast, papillary carcinoma of thyroid gland, dysgerminoma, Hodgkin lymphoma, seminoma, ameloblastoma and benign cystic teratoma. 6 Tumor associated granulomatous reaction has largely been attributed to the cytokine milieu of the main tumor or the other cells of the background. 9 Epithelioid granulomas with suppuration were seen in fungal infection (76.9%), tuberculosis, cat-scratch disease and leishmaniasis.…”