AKT · Respiratory/ILD, sarcoid & occupationallow yield

Sarcoidosis

Multisystem granulomatous disease of unknown cause — non-caseating granulomas

Overview

A multisystem granulomatous disease of unknown cause, characterised by non-caseating granulomas, most often affecting the lungs and intrathoracic lymph nodes. It ranges from an acute self-limiting form (Löfgren syndrome — bilateral hilar lymphadenopathy + erythema nodosum + arthralgia, good prognosis) to chronic pulmonary fibrosis and extra-pulmonary disease. Bilateral hilar lymphadenopathy on CXR is the classic finding.

Recognise

Often young adults; dry cough, breathlessness, fatigue; BILATERAL HILAR LYMPHADENOPATHY on CXR (the hallmark)
Löfgren syndrome (acute, good prognosis): bilateral hilar lymphadenopathy + erythema nodosum + arthralgia ± fever
Extra-pulmonary: skin (erythema nodosum, lupus pernio), eyes (uveitis), hypercalcaemia, cardiac (arrhythmia/heart block), neuro, parotid; raised serum ACE

Red flags

Cardiac sarcoid (arrhythmia/heart block), neurosarcoidosis, or sight-threatening uveitis → urgent specialist treatment
Hypercalcaemia (granulomas activate vitamin D) → treat; advise avoiding excess vitamin D/sun

Differentials & how to tell them apart

Tuberculosiscaseating granulomas, AFB-positive — must be excluded (biopsy/culture) before immunosuppressing

Lymphomalymphadenopathy with systemic features — biopsy distinguishes

Other ILD / hypersensitivity pneumonitisdifferent HRCT pattern/exposure history

Investigations

CXR (bilateral hilar lymphadenopathy ± infiltrates — staged 0–IV); HRCT; serum ACE (supportive, non-specific), calcium (often raised); spirometry/DLCO; tissue biopsy (non-caseating granulomas — to confirm and exclude TB/lymphoma); ECG/echo (cardiac), eye review.

Management

Observe (often remits); corticosteroids for significant pulmonary/cardiac/neuro/ocular/hypercalcaemic disease

1Recognise bilateral hilar lymphadenopathy ± systemic features; support with serum ACE/calcium and confirm with biopsy (non-caseating granulomas) — crucially EXCLUDING TB and lymphoma first. Many cases (Löfgren) need only observation.Gate: Don't immunosuppress until TB is excluded; treat significant disease — progressive lung involvement, hypercalcaemia, or cardiac/neuro/ocular sarcoid → corticosteroids.
2Corticosteroids for significant organ disease; methotrexate as a steroid-sparing agent for chronic disease; manage hypercalcaemia and organ-specific complications.

Often no treatment (observe) — many remit spontaneously — acute disease/Löfgren syndrome usually self-limits; NSAIDs for arthralgia/erythema nodosum

Corticosteroids for significant disease — progressive pulmonary disease, hypercalcaemia, cardiac/neuro/ocular involvement

Steroid-sparing immunosuppression (methotrexate) — for chronic/steroid-dependent disease

Treat hypercalcaemia + organ-specific disease — avoid excess vitamin D/sunlight; cardiac/ophthalmic management

Key points

Young adult + bilateral hilar lymphadenopathy + raised ACE/calcium = sarcoidosis (non-caseating granulomas) → many observe (Löfgren = BHL + erythema nodosum + arthralgia, good prognosis); steroids for significant pulmonary/cardiac/neuro/ocular/hypercalcaemic disease. EXCLUDE TB/lymphoma before immunosuppressing.

Monitor & prognosis

Symptoms/CXR stage, lung function, calcium, organ-specific surveillance (cardiac/eye).

Many remit spontaneously; chronic pulmonary fibrosis and cardiac/neuro disease worsen it.

Source: BTS/ATS sarcoidosis