<P> Granuloma with central necrosis in a lung of a person with tuberculosis . Note the Langhans - type giant cells (with many nuclei arranged in a horseshoe - like pattern at the edge of the cell) around the periphery of the granuloma . Langhans - type giant cells are seen in many types of granulomas, and are not specific for tuberculosis . </P> <P> The granulomas of tuberculosis tend to contain necrosis ("caseating tubercules"), but non-necrotizing granulomas may also be present . Multinucleated giant cells with nuclei arranged like a horseshoe (Langhans giant cell) and foreign body giant cells are often present, but are not specific for tuberculosis . A definitive diagnosis of tuberculosis requires identification of the causative organism by microbiologic cultures . </P> <P> In leprosy, granulomas are found in the skin and tend to involve nerves . The appearance of the granulomas differs according to the precise type of leprosy . </P> <P> Some schistosome ova that are laid in intestinal and urinary venules backwash into the liver via the portal vein causing granuloma formation in the liver . </P>

Medical term that means inflammation of a vein