30th April 2024

A 40-year-old man presents with a three-month history of dry cough, shortness of breath, and mild chest pain.

A 40-year-old man presents with a three-month history of dry cough, shortness of breath, and mild chest pain. He also reports occasional fevers and unexplained weight loss. Physical examination reveals enlarged lymph nodes in the neck. A chest X-ray shows bilateral hilar lymphadenopathy. The patient has no significant past medical history or known exposure to tuberculosis.

Investigations:

Full Blood Count: Normal

Serum Urea and Creatinine: Normal

Liver Enzymes: Elevated

Serum Calcium: Elevated

Pulmonary Function Tests: Restrictive Pattern

Which investigation is most appropriate to confirm the diagnosis of sarcoidosis in this patient?