Sarcoidosis

- multisystem granulomatous disorder of unknown cause
- prevalence highest in Northern Europe
- 20-40% asymptomatic, discovered incidentally after routine CXR
- acute sarcoidosis presents with erythema nodosum and polyarthralgia which resolves spontaneously
- serum ACE elevated in 60% of patients, presumably reflecting macrophage activity
- transbronchial biopsy provide positive histology in 80% of patients
- Kveim reaction, a granulomatous reaction appearing 4 weeks after intradermal injection of sarcoid spleen or lymph node extract is positive in 50-60% of patients
- Mikulicz syndrome : sarcoidosis with parotid gland enlargement
- Heerfordt's syndrome (uveoparotid fever) : Mikulicz syndrome with acute uveitis and facial nerve palsy