Idiopathic disease is the most frequent diagnosis in a uveitis clinic. The need to distinguish sarcoidosis from idiopathic uveitis is controversial. However, cardiac involvement in sarcoidosis can be life-threatening. The study reports a series of patients with uveitis and cardiac sarcoidosis to illustrate the importance of categorizing the causes of uveitis

The researchers conducted a retrospective observational case series and reviewed the medical records of 249 patients with uveitis who were referred to the Casey Eye Institute between July 1, 2008, and February 28, 2017. Researchers describe patients who initially received a diagnosis of idiopathic uveitis but subsequently received a diagnosis of sarcoidosis. Clinical data, including ophthalmologic findings, were collected. 

The patients who presented with idiopathic uveitis, who had recived a classification of idiopathic uveitis after evaluation, the number of patients who underwent chest computed tomography or an electrocardiogram, and the number of patients with ocular sarcoidosis.

Of 33 patients with sarcoidosis , 21 (63.6%) were women and the mean (SD) age was 53.5 (13.8) years. Of 249 patients, the referring diagnosis was idiopathic uveitis for 179 (72%). After history, examination, and laboratory testing, 127 (51%) were still considered to have idiopathic disease.

Fifty-three of the 179 patients (30%) with idiopathic disease underwent chest computed tomography scanning. A diagnosis of presumed sarcoidosis, usually on the basis of a chest computed tomography scan, was made in 19 patients (36.2%).

As 14 patients (5.6%) were previously known to have sarcoidosis, 33 patients (13.3%) were evaluated with definite or presumed ocular sarcoidosis. Researchers obtained electrocardiograms as a screen for cardiac sarcoidosis on 14 (42.4%) of these patients. Nine patients with abnormal electrocardiogram results were referred to cardiologists.

Four of the 19 patients (21.1%) who were referred for idiopathic uveitis but later received a diagnosis of presumed sarcoidosis were found to have episodes of ventricular tachycardia that required implantable cardiac defibrillators. Distinguishing ocular sarcoidosis from idiopathic uveitis had potentially life-saving implications for these patients.

The present case series showed the potential utility of distinguishing sarcoidosis-associated uveitis from idiopathic uveitis. They suggest that patients older than 40 years with a history of idiopathic uveitis have been evaluated with chest computed tomography and an electrocardiogram if sarcoidosis is suggested on ophthalmic examination .