Sarcoidosis

Sarcoidosis is a systemic granulomatous disease of unknown cause. The inflammation associated with sarcoidosis typically causes noncaseating granulomas. Sarcoidosis commonly involves the lungs, eyes, skin, lymph nodes, and liver. Although the highest incidence of sarcoidosis in the United States is observed in young African-American women, more White Americans than African Americans have sarcoidosis. More than 90% of patients with sarcoidosis have evidence of pulmonary involvement. The most common radiologic finding is hilar adenopathy. The most common cause of death from sarcoidosis is related to advanced pulmonary disease and respiratory failure. Cardiac sarcoidosis is also a common cause of death from sarcoidosis. These deaths may be sudden and may occur early in the course of the disease. Löfgren’s syndrome, the combination of fever, erythema nodosum, bilateral hilar adenopathy, symmetric polyarthritis, and uveitis, is one mode of acute presentation in sarcoidosis. The Heerfordt syndrome, another acute presentation that is sometimes termed “uveo-parotid fever,” consists of fever, uveitis, granulomatous inflammation of the lacrimal and parotid glands, bilateral hilar adenopathy, and cranial neuropathies. Ninety percent of patients with sarcoidosis have evidence of pulmonary disease on chest radiography. The most common finding is hilar adenopathy. Ocular involvement is a common complication of sarcoidosis. The usual ocular manifestations are anterior uveitis and pars planitis. However, posterior uveitis and optic neuritis may also occur. Sarcoidosis is one of a small number of conditions, in fact, that can cause panuveitis. (Another common cause of panuveitis is Behcet’s syndrome). Posterior uveitis can remain asymptomatic until it has reached advanced stages. Thus, screening for ophthalmologic disease is important for sarcoidosis patients. The diagnosis of sarcoidosis is established by integrating together information from the clinical presentation, radiologic features, histopathological findings, and response to therapy. Glucocorticoids remain the cornerstone of therapy for active sarcoidosis. For patients with atypical presentations of sarcoidosis, particularly those with a history or frequent or severe infections, screening for antibody deficiency and consideration of a referral for immunology evaluation may be useful in establishing the diagnosis of granulomatous-lymphocytic interstitial lung disease (GLILD), a condition that mimics sarcoidosis closely but requires different treatment considerations.