Pathology

Abstract

The histological pattern that characterizes sarcoidosis can be described briefly as a non-caseating tuberculoid granulomatosis. Granulomatosis is here defined as a chronic inflammatory response in which cells of the mononuclear phagocyte series are prominent, usually forming focal aggregations (Williams and Williams, 1983). When these are well-marked, they are recognizable as tubercles. Knowledge of this sort of inflammation started from the study of the disease which owes its name, tuberculosis, to the recognition of the tubercle as its distinctive morbid-anatomical characteristic, but since Koch discovered its causal agent, it has been definable, and now is generally defined, aetiologically. In the following discussions, the word ‘tubercle’ is used in its original morbid-anatomical sense, without aetiological implications.