Sarcoidosis has innumerable clinical manifestations, as the disease may affect every body organ. Furthermore, the severity of sarcoidosis involvement may range from an asymptomatic state to a life-threatening condition. This manuscript reviews a wide variety of common and less common clinical characteristics of sarcoidosis. These manifestations are presented organ by organ, although additional sections describe systemic and multiorgan presentations of sarcoidosis. The lung is the organ most commonly involved with sarcoidosis with at least 90 % of sarcoidosis patients demonstrating lung involvement in most series. The skin, eye, liver, and peripheral lymph node are the next most commonly clinically involved organs in most series, with the frequency of involvement ranging from 10 to 30 %. The actual frequency of sarcoidosis organ involvement is probably much higher as it is frequently asymptomatic and may avoid detection. This is particularly common with lung, liver, cardiac, and bone involvement. Cardiac sarcoidosis is present in 25 % of all sarcoidosis but only causes clinical problems in 5 % of them. Nevertheless, unlike sarcoidosis involvement of most other organs, it may be suddenly fatal. Therefore, it is important to screen for cardiac sarcoidosis in all sarcoidosis patients. All sarcoidosis patients should also be screened for eye involvement as asymptomatic patients may have eye involvement that may cause permanent vision impairment. Pulmonary fibrosis from sarcoidosis is usually slowly progressive but may be life-threatening because of the development of respiratory failure, pulmonary hypertension, or hemoptysis related to a mycetoma or bronchiectasis. Some manifestations of sarcoidosis are not organ-specific and probably are the result of a release of mediators from the sarcoid granuloma. Two such manifestations include small fiber neuropathy and fatigue syndromes, and they are observed in a large percentage of patients.
