[Sarcoidosis, a disease with many facets]

Sarcoidosis is a multisystem granulomatous disorder of unknown aetiology, most commonly affecting young adults. The course and the prognosis may correlate with the mode of onset. An acute onset with erythema nodosum heralds a self-limiting course and spontaneous resolution, whereas an insidious onset may be followed by relentless, progressive fibrosis.