SARCOIDOSIS

Multisystem granulomatous disease of unknown etiology.

I.   Epidemiology

• Women>men (6.3 vs 5.9 cases/100k)
• Most frequent <40yo
•  Blacks (2.4% lifetime risk), Swedes, Danes most prevalent

II. Etiology/Pathology

•  Noncaseating granulomata formed by T cells & monocytes
• Etiology unknown: genetic, infectious (viral, mycobacteria, B. burgdorferi, P acnes), environmental (alum, beryllium, zirconium)
• ?Genetically predetermined host with exposure to env agent triggering inflammatory response

III. Clinical features

• Clinical manifestations are secondary to structural distortion of tissues from the granulomas; can get permanent loss of function, however, from prolonged involvement & scarring
• Clinical course is variable; can be acute/self-limiting but usually have insidious onset over months
• 33% with consitutional sx: fever, fatigue, malaise, anorexia, weight loss
• 30-50% ASx Dx on CXR
• Acute:  Whites>Blacks, freq spontaneous remission
• Lofgren's Syndrome: B hilar LAD, ankle arthritis, erythema nodosum, fever, myalgias, wt loss, occ spontaneous remission
• Chronic:  insidious onset, 10-30% patients, spontaneous remission in 67%, Blacks with worse Px
• Organs:

• Polyarthritis

• Pulmonic sx: cough, dyspnea, chest pain (most common sx); interstitial lung disease is the most common type of pulmonic involvement

• Peripheral, including thoracic, nontender lymphadenopathy (very common)

• Mild anemia due to BM involvement

• Skin involvement, esp. erythema nodosum (25% of pts)

• Eye involvement (25% of pts): sx include blurred vision, tearing, photophobia; can cause blindness

• Nasal stuffiness (20% of pts)

IV. Treatment

1. Corticosteroids have traditionally been the mainstay of treatment
   1. In a systematic review of 8 randomized trials, oral corticosteroids were found to be ass'd with radiologic improvement c/w placebo; also improvements in pulmolnary function and sx (the latter two limited to pst with "stage 2" or "stage 3" disease); data on inhaled steroids is limited and inconclusive (JAMA 287:1301, 2002--AFP)