Sarcoidosis

• • Also known as Boeck sarcoid, benign lymphogranulomatosis

  • Noncaseating granulomatous disease involving lungs, liver, spleen, lymph, skin, and bones

  • Cause is unknown

  • 20% have myocardial involvement

  • 30% have cutaneous involvement

  • 70% have hepatic and splenic involvement

  • Mediastinal and scalene lymph nodes microscopically involved in 90% and 80%, respectively

Epidemiology

• • Highest incidence: Scandinavia, England, United States

  • Incidence in blacks 15 fold that of whites

  • 50% between ages 20 and 40 years

  • Women affected more often than men

Symptoms and Signs

• • May present with nonspecific pulmonary symptoms (20-30%), including fever (15%) and cough

  • Erythema nodosum may herald onset

  • Weight loss, fatigue, weakness, malaise, enlarged lymph nodes (75%)

  • Migratory or persistent polyarthritis

  • CNS symptoms (rarely)

Laboratory Findings

• • Elevated serum and bronchoalveolar ACE levels

  • Elevated lysozyme levels

Imaging Findings

• • Chest film: 5 stages

  • -Stage 0: No abnormality

    -Stage 1: Hilar/mediastinal adenopathy alone

    -Stage 2: Hilar adenopathy with pulmonary abnormalities

    -Stage 3: Diffuse pulmonary disease without adenopathy

    -Stage 4: Pulmonary fibrosis

  • Mediastinal lymph node involvement characteristically bilateral and symmetric

  • Asymmetric hilar adenopathy: Consider lymphoma or other disease

  • Pleural effusions/cavitation rare: Consider TB, pneumonia

• • Diagnosis of exclusion

  • Suggested by chest film, gallium 67 scanning, elevated serum and bronchoalveolar ACE and lysozyme levels

  • Pathologic documentation of noncaseating granulomas via transbronchial or mediastinoscopy

Rule Out

• • Hodgkin disease

  • Non-Hodgkin lymphoma

• • Chest x-ray

  • Chest CT scan

  • Bronchoscopy and biopsy if pulmonary compromise

• • No therapy needed for asymptomatic patients

  • Corticosteroids for patients with pulmonary impairment or are symptomatic

Complications

• • Corticosteroid side effects

Prognosis

• • Long-term mortality as high as 10%

References