Pulmonary sarcoidosis

Sarcoidosis can occur after genetically susceptible individuals have been exposed to unidentified environmental antigens. Diagnosis requires clinical evaluation, chest radiography, lung function testing, judicious tissue biopsy (endobronchial ultrasound now being a preferred method) and exclusion of other granulomatous disease. No long-term systemic therapy is usually needed for the common presentation of Löfgren's syndrome (bilateral hilar lymphadenopathy, erythema nodosum, transient iritis). Corticosteroids remain first-line therapy, indicated for all patients presenting with pulmonary infiltrates and impaired lung function, and for those with critical extrathoracic organ dysfunction or hypercalcaemia. Corticosteroid-sparing immunosuppressive agents such as methotrexate, azathioprine (both used off-label for sarcoid in the UK) or hydroxychloroquine is frequently needed to minimize drug toxicities. Certain anti-tumour necrosis factor-α agents, (infliximab, adalimumab; unlicensed use in the UK) sometimes have a useful niche role in refractory disease as a supplement to other therapies, with 18fluorodeoxyglucose positron emission tomography increasingly useful in assessment of refractory disease. Methylphenidate can help sarcoidosis-related fatigue (unlicensed use in the UK). Pulmonary hypertension can complicate advanced pulmonary sarcoidosis, increasing the rate of mortality from various forms of sarcoid-related pulmonary vasculopathy. Treatment options include epoprostenol, sildenafil or bosentan. Lung transplantation is successful in end-stage fibrotic disease, but sarcoid granulomas can reoccur in the allograft, and fungal contamination of fibro-bullous cavities can confer an increased postoperative risk of systemic infection.