The histopathological study of granulomatous diseases in various organ to find the exact etiology of granulomas

The granulomatous inflammatory response is ubiquitous in pathology, being a manifestation of many infections, toxic, allergic, autoimmune and neoplastic diseases, vasculitis, immunological aberration, leukocyte oxidase deficiency, hypersensitivity, chemicals, and also conditions of unknown etiology. Schistosomiasis, tuberculosis and leprosy, all infective granulomatous diseases, together affect more than 200 million people worldwide, and granulomatous reactions to other irritants are a regular occurrence in everyday clinical histopathology.


Introduction
The granulomatous inflammatory response is ubiquitous in pathology, being a manifestation of many infections, toxic, allergic, autoimmune and neoplastic diseases, vasculitis, immunological aberration, leukocyte oxidase deficiency, hypersensitivity, chemicals, and also conditions of unknown etiology. Schistosomiasis, tuberculosis and leprosy, all infective granulomatous diseases, together affect more than 200 million people worldwide, and granulomatous reactions to other irritants are a regular occurrence in everyday clinical histopathology. 1 Granulomatous inflammation is best defined as a special variety of chronic inflammation in which cells of the mononuclear phagocyte system are predominant and take the form of macrophages, epithelioid cells and multinucleated giant cells. In most instances, these cells are aggregated into well demarcated focal lesions called granulomas, although a loose, more diffuse arrangement may be found. In addition there is usually an admixture of other cells, especially lymphocytes, plasma cells and fibroblasts. 1 Granulomatous inflammation is a distinctive pattern of chronic inflammation and adaptive immunity and the granuloma is the hallmark of many human diseases of great significance, the most important of which is tuberculosis. 2,3 Its formation is firmly linked to the type IV(delayed type) hypersensitivity reaction which is a form of adaptive cell-mediated immunity that is mediated by activated T lymphocytes and their products, called cytokines. Recognition of granulomatous inflammation on histology is very important because of the fairly limited number of conditions that give rise to granulomas and the clinical significance of these diagnoses.

Materials and Method
The present study was undertaken from January 2011 to July 2012 in the Department of Pathology, SBKS MI & RC, Piparia, Vadodara. For the cytological study, FNAC was done in clinically diagnosed and suspected cases of granuloma. All the cases which were clinically diagnosed and suspected of granulomas, on haematoxylin and eosin stained sections were studied. Special stains like Ziehl Neelsen stain, PAS stain and Fite Faraco stain were done whenever required.
Total 130 cases of clinically diagnosed and suspected cases of Granulomatous lesions were studied. Out of total 130 cases, the 98 cases were studied with Histopathological and cytological examination, 25 cases with the histopathological examination only, 7 cases only with cytological examination. The most common site of the granulomatous diseases was in lymph nodes(72 cases), followed by skin and subcutaneous tissue (10 cases), neck (12 cases), respiratory system (7 cases), spine (7 cases), bones and joints (5 cases), gastrointestinal tract(6 cases), female reproductive system(5 cases), male reproductive system (2 cases) and 1 case each in ear, umbilicus, CNS and muscle.

Result
The present study of 130 cases (Male=58 cases and Female=72cases) was carried out to detect the incidence of various types of granulomatous diseases in various organs with help of cytological and histo-pathological examinations. Out of total 130 cases,98 cases were studied with both histo-pathological and cytological examination, 25 cases with histopathological examination only, 7 cases only with cytological examination.

Discussion
Below table revealed that incidence of tuberculosis (82%) in our study is slightly higher than other two Karnataka studies, Jayashree pawal et al study (49%)and Harish permi et al study (47%). Even though leprosy is common in Gujarat but may be due to less samples size.
Out of total 130 cases, a definite aetiological diagnosis could be made only in 123 cases. Even after relevant special stains, the aetiological diagnosis could be confirmed only in 95% cases. Cooperation between the clinician and the pathologist is more important to derive the greatest benefit from the biopsy.
All these analytical results highlight the various pitfalls of cytological study so that it cannot be relied upon as a sole diagnostic criterion. Other reasons can be inadequate aspiration, poor quality of staining and mounting.
However, 78.57% of cases were correctly diagnosed on cytological study, hence its advantages as a simple, non invasive procedure for earliest diagnosis of various granulomatous diseases cannot be overlooked. Additional tests like culture, serological investigations and PCR may be necessary to confirm the results. Cytological study has its limitations which cannot be overcome; however diagnostic rate of granulomatous diseases can be increased by combining it with other confirmatory tests.