Sarcoidosis

A systemic inflammatory diseaseCharacterized by non-caseating

granulomas

Pathophysiology Exact cause not known In genetically susceptible individuals possible

altered immune response after exposure to environmental or infectious agent (mycobacteria/Propionibacterium)

Increased macrophage & CD4 T-helper cell activation causes inflammation

Suppressed IL-2 secretion causes anergy Macrophages convert vit. D to its active form

Clinical features Pulmonary- B/L hilar adenopathy,

obstructive/restrictive disease causes progressive SOB & dry cough

Eye- uveitis, granulomatous conjunctivitis, optic neuritis/retinitis

Skin- nodules/plaques over face/extensor surfaces of limbs

URT- nasal congestion, sinusitis, hoarseness Cardiac- arrythmia, DCMP, sudden death Neuro- cranial n. palsy-VII, VIII, IX, II, III, V, aseptic

meningitis, SOL, polyneuropathy, mononeuritis multiplex

HSmegaly, PLNE, arthralgias, parotid/lacrimal gland enlargement/dysfunction

Hypercalcemia, hypercalciuria, nephrolithiasis etc.

Symptom complex Lupus pernio- disfiguring facial cutaneous

involvement with violaceous plaques & nodules

Lofgren syndrome- acute presentation with erythema nodosum, B/L hilar LNE, uveitis, polyarthritis

Heerfordt syndrome-acute presentation with fever, parotod/lacrimal gland enlargement, uveitis, B/L hilar LNE, cranial neuropathies

Diagnosis

Biopsy of most easily accessible tissue

Showing non-caseating granulomatous inflammation

Diagnosis- supportive CxR- helps in staging CT chest PET scan PFT RFT, LFT, Ca levels Serum ACE levels Negative Montoux test ECG MRI brain- for CNS involvement

Staging Based on CxR I- B/L hilar LNE II- + reticulonodular infiltrates III- B/L pulmonary infiltrates IV- fibrocystic disease

Pleural effusion is rare DDx- TB, fungal infection, lymphoma,

Wegener’s granulomatosis

Treatment Not all need to be treated, ~50% need Spontaneous remission is known Indications- Persistent, symptomatic, progressive lung disease Disfiguring skin disease or peripheral LNE Threatened organ failure- eye, heart, CNS Persistent hypercalcemia, deranged RFT/LFT Uveitis, not responding to local steroids Hypersplenism

Drugs

Steroids- oral prednisone x 1 year/more

Steroid-sparing agents, if required

Prognosis Variable Spontaneous remission is known Chronic disease, with exacerbations &

remissions Can progress to fibrosis, cor pulmonale,

respiratory failure Increased risk of lymphoma Systemic, specially cardiac involvement,

suggests bad prognosis