**1. Introduction**

Sarcoidosis is a multi-organ, granulomatous disease of unknown etiology characterized by T-cell dysfunction and B-cell hyperactivity with increased local immune activity and inflammation that leads to the formation of noncaseating granulomas in the organs involved [1]. The lung and lymphatic system are the most commonly affected organs, but virtually any organ may be affected [2]. Other common sites of involvement include the skin, eye, central nervous system (CNS), and the heart [3]. Patients may present with different symptoms related to the disease stage and the specific organ involved [4]. Sarcoidosis is a global disease, and its prevalence has increased twofold over the past years [5]. Due to the clinical heterogeneity and variable diagnostic criteria in different countries, it is difficult to calculate the exact prevalence and incidence of sarcoidosis. Age, sex, race, and geographic origin significantly influence the incidence rate of sarcoidosis [6]. A definite diagnosis of the disease when an identifiable etiology and definitive diagnostic criteria is lacking remains challenging [3].
