Sarcoidosis

• multisystem granulomatous disorder of unknown aetiology characterised by non-caseating granulomas. It is more common in young adults (age 20 - 40) and in people of African descent
• asso: with HLA-DRB1 and DQB1

Features

• acute: erythema nodosum, bilateral hilar lymphadenopathy, swinging fever, polyarthralgia
• insidious: dyspnoea, non-productive cough, malaise, weight loss
• ocular: uveitis
• lupus pernio
  • chronic violaceous indurated plaques on the nose/face
  • associated with upper respiratory tract involvement.
  • indicates chronic disease and poor prognosis; often requires systemic therapy.
• hypercalcaemia: macrophages inside the granulomas cause an increased conversion of vitamin D to its active form (1,25-dihydroxycholecalciferol)

Two distinct sarcoid syndromes with acute presentation:

1. Löfgren syndrome - LoFj(g)rEN syndrome = Lymph node, Fever, joint pain, and erythema nodosum
2. Heerfordt-Waldenstrom syndrome - fever, parotid enlargement, uveitis, and facial palsy (called uveoparotid fever)

Hilar and left paratracheal adenopathy is the most common presentation in sarcoidosis.

15-20% of patients w/ sarcoidosis can have ocular involvement, and from these patients, 5% will have it as the primary presenting symptom. (most common - anterior uveitis)

Bone X-rays show "punched out" lesions in terminal phalanges

Sarcoidosis CXR

Stages: