Sarcoidosis: clinical mimicry of pulmonary embolism.

Sarcoidosis can manifest with clinical signs suggestive of pulmonary embolism (PE). A 36-year-old male patient presented with a 2-day history of left-sided pleuritic chest pain and dyspnoea. He was hypoxicand tachypnoeic, and initial blood tests showed a positive plasma D-dimer. Subsequent arterial blood gas showed respiratory alkalosis with type 1 respiratory failure. He was suspected to have a PE, and CT pulmonary angiogram (CTPA) was urgently arranged. This latter investigation did not show any impairment in pulmonary arterial blood flow but revealed bilateral hilar and mediastinal lymphadenopathy suggesting sarcoidosis. Serum calcium and ACE were also elevated. The patient was treated conservatively and discharged after 2 days with out-patient endobronchial ultrasound and clinic follow-up arranged.