Epitheloid granuloma consists mainly of which type of cells: March 2005

Ans. D: MacrophagesMacrophages/ histiocytes are the cells that define a granuloma. They often, but not invariably, fuse to form multinucleated giant cells.The macrophages in granulomas are often referred to as "epithelioid".Epithelioid macrophages differ from ordinary macrophages in that they have elongated nuclei that often resemble the sole of a slipper or shoe. They also have larger nuclei than ordinary macrophages and their cytoplasm is typically more pink when stained with eosin.Granulomas are seen in a wide variety of diseases, both infectious and non-infectious.A.Infections that are characterized by granulomas include tuberculosis, leprosy, histoplasmosis, cryptococcosis, coccidioidomycosis, blastomycosis and cat scratch disease.B.Examples of non-infectious granulomatous diseases are sarcoidosis Sarcoid granulomas often contain star-shaped structures termed asteroid bodies or lamellar structures termed Schaumann bodies., Crohn's disease, berylliosis, Wegener's granulomatosis, Churg-Strauss syndrome, pulmonary rheumatoid nodules and aspiration of food and other paiculate material into the lung.