Sarcoidosis from bench to bedside: a state-of-the-art series for the clinician.

F irst described in 1899 [1], sarcoidosis is a multi-organ granulomatous disorder that remains an enigma and challenges researchers and clinicians due to its unknown aetiology, variegated presentation and an unpredictable, and occasionally severe or even fatal, outcome despite therapy. As over 90% of patients have involvement of the lungs and thoracic lymph nodes, most chest physicians encounter sarcoidosis regularly in their practice, and have to manage this disorder with a risk of delayed or inadequate care [1].