Sarcoidosis

• Sarcoidosis is a rare multisystem granulomatous disorder of unknown aetiology. The granulomas are inflammatory nodules full of macrophages. It is a multisystem disorder but commonly affects the lungs.
• Demographics:

  • Age of onset 20-40
  • More common in females
  • More common in people of black ethnic origin
• Skin features:

  • Erythema nodosum - nodules of inflamed subcutaneous fat on the shins
  • Lupus pernio - specific to sarcoidosis and presents with raised purple skin lesions, often on the cheeks and nose
• Erythema nodosum presents as raised, red, tender, painful, subcutaneous nodules across both shins
• Pulmonary manifestations:

  • Mediastinal lymphadenopathy
  • Pulmonary fibrosis
  • Pulmonary nodules
• Symptoms can vary depending on which systems are affected:

  • Cough (dry)
  • SOB
  • Red or painful eyes
  • Swollen glands
  • Skin rashes
  • Pain in joints, muscles or bones
  • Numbness or weakness of the face, arms and legs
• Systemic features:

  • Fever/night sweats
  • Fatigue
  • Weight loss
• Liver manifestations:

  • Liver nodules
  • Cirrhosis
  • Cholestasis
• Eye manifestations:

  • Uveitis
  • Conjunctivitis
  • Optic neuritis
• Cardiac manifestations:

  • BBB
  • AV node block
  • Myocardial muscle involvement
• Renal manifestations:

  • Stones - due to hypercalcaemia
  • Nephrocalcinosis
  • Interstitial nephritis
• CNS manifestations:

  • Nodules
  • Pituitary involvement e.g. diabetes insipidus
  • Encephalopathy
• PNS manifestations:

  • Facial nerve palsy
  • Mononeuritis multiplex
• Bone manifestations:

  • Arthralgia (joint pain)
  • Arthritis
  • Myopathy
• Lofgren's syndrome refers to a specific presentation of sarcoidosis with a classic triad of symptoms:

  • Erythema nodosum
  • Bilateral hilar lymphadenopathy
  • Polyarthralgia
• Blood tests:

  • Raised angiotensin-converting enzyme (ACE)
  • Hypercalcaemia
• Imaging:

  • CXR may show hilar lymphadenopathy
  • HRCT may show hilar lymphadenopathy and pulmonary nodules
  • MRI can show CNS involvement
  • PET scan can show active inflammation in affected areas
• Histology:

  • Bronchoscopy with an US guided biopsy of mediastinal lymph nodes
  • Histology characteristically shows non-caseating granulomas with epithelioid cells
• Management:

  • Conservative management considered in patients with no or mild symptoms
  • Oral steroids (6-24 months) are usually first line when treatment is required
  • Bisphosphonates protect against osteoporosis whilst on long-term steroids
  • Methotrexate is a second line option
  • Lung transplant rarely required