Sarcoidosis - Angiotensin Converting Enzyme

Sarcoidosis - Angiotensin Converting Enzyme

 

Sarcoidosis is a systemic disorder of unknown etiology, characterized by granuloma formation.

Epidemiology

  • Incidence – 10-15/100,000 in U.S.; 40/100,000 in some North European countries
  • Age – peak incidence 20-39 years
  • Ethnicity – most prevalent in Swedish, Danish and African Americans
  • Gender – F>M

Pathophysiology

  • Accumulation of activated T-cells and macrophages at site of disease activity
  • Lymphocytes are CD4 type
  • Macrophages release cytokines that drive inflammation, granuloma formation and eventual fibrosis

Clinical Presentation

  • Asymptomatic (30-50%) diagnosed by routine chest X-ray with abnormalities of hilar adenopathy
  • Nonspecific (30%) – fever, weight loss, fatigue
  • Pulmonary (85-90%)
    • Löfgren syndrome – bilateral hilar adenopathy, ankle arthritis, fever, myalgia, weight loss and erythema nodosum
    • Dyspnea, wheezing
  • Dermatologic – maculopapular rashes, plaques and nodules, erythema nodosum and lupus pernio
  • Cardiac – rhythm disorders, infiltrative cardiomyopathy and pericarditis
  • Ophthalmic – anterior uveitis
  • Hepatic/Splenic – granulomas, but dysfunction is rare
  • Endocrine – hypercalcemia with nephrolithiasis
  • Central nervous system (CNS) – neurosarcoidosis is an uncommon, but serious manifestation of sarcoidosis, affecting about 5-10% of patients
    • The most common manifestations include myelopathy, cranial neuropathy and encephalopathy
    • Untreated patients may develop acute neurologic emergencies, including seizures, cord compression and increased intracranial pressure

Diagnosis

  • Histology
    • Tissue biopsy demonstrating noncaseating granulomas, with appropriate clinical presentation
    • If biopsy is negative, ACE levels and CD4/CD8 in bronchioalveolar lavage may be helpful (both lack specificity)
  • Laboratory testing
    • ACE levels may be followed for disease activity
    • CSF analysis
      • CSF ACE levels may help support diagnosis of neurosarcoidosis; however is not specific for neurosarcoidosis

See Also