Sarcoidosis

Sarcoidosis is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomas. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly affected are the eyes, liver, heart, and brain. Any organ, however, can be affected. The signs and symptoms depend on the organ involved. Often, no, or only mild, symptoms are seen. When it affects the lungs, wheezing, coughing, shortness of breath, or chest pain may occur. Some may have Löfgren syndrome with fever, large lymph nodes, arthritis, and a rash known as erythema nodosum.Sarcoidosis in a lymph nodeAsteroid body in sarcoidosisMicrograph showing pulmonary sarcoidosis with granulomas with asteroid bodies, H&E stainHilar adenopathy especially on the person's left (AP CXR)Hilar adenopathy especially on the person's left (lateral CXR)Hilar adenopathy especially on the person's left (coronal CT)Hilar adenopathy especially on the person's left (transverse CT) Sarcoidosis is a disease involving abnormal collections of inflammatory cells that form lumps known as granulomas. The disease usually begins in the lungs, skin, or lymph nodes. Less commonly affected are the eyes, liver, heart, and brain. Any organ, however, can be affected. The signs and symptoms depend on the organ involved. Often, no, or only mild, symptoms are seen. When it affects the lungs, wheezing, coughing, shortness of breath, or chest pain may occur. Some may have Löfgren syndrome with fever, large lymph nodes, arthritis, and a rash known as erythema nodosum. The cause of sarcoidosis is unknown. Some believe it may be due to an immune reaction to a trigger such as an infection or chemicals in those who are genetically predisposed. Those with affected family members are at greater risk. Diagnosis is partly based on signs and symptoms, which may be supported by biopsy. Findings that make it likely include large lymph nodes at the root of the lung on both sides, high blood calcium with a normal parathyroid hormone level, or elevated levels of angiotensin converting enzyme in the blood. The diagnosis should only be made after excluding other possible causes of similar symptoms such as tuberculosis. Sarcoidosis may resolve without any treatment within a few years. However, some people may have long-term or severe disease. Some symptoms may be improved with the use of anti-inflammatory drugs such as ibuprofen. In cases where the condition causes significant health problems, steroids such as prednisone are indicated. Medications such as methotrexate, chloroquine, or azathioprine may occasionally be used in an effort to decrease the side effects of steroids. The risk of death is 1-7%. The chance of the disease returning in someone who has had it previously is less than 5%. In 2015, pulmonary sarcoidosis and interstitial lung disease affected 1.9 million people globally and they resulted in 122,000 deaths. It is most common in Scandinavians, but occurs in all parts of the world. In the United States risk is greater among black as opposed to white people. It usually begins between the ages of 20 and 50. It occurs more often in women than men. Sarcoidosis was first described in 1877 by the English doctor Jonathan Hutchinson as a nonpainful skin disease. Sarcoidosis is a systemic inflammatory disease that can affect any organ, although it can be asymptomatic and is discovered by accident in about 5% of cases. Common symptoms, which tend to be vague, include fatigue (unrelieved by sleep; occurs in 66% of cases), lack of energy, weight loss, joint aches and pains (which occur in about 70% of cases), arthritis (14–38% of persons), dry eyes, swelling of the knees, blurry vision, shortness of breath, a dry, hacking cough, or skin lesions. Less commonly, people may cough up blood. The cutaneous symptoms vary, and range from rashes and noduli (small bumps) to erythema nodosum, granuloma annulare, or lupus pernio. Sarcoidosis and cancer may mimic one another, making the distinction difficult. The combination of erythema nodosum, bilateral hilar lymphadenopathy, and joint pain is called Löfgren syndrome, which has a relatively good prognosis. This form of the disease occurs significantly more often in Scandinavian patients than in those of non-Scandinavian origin. Localization to the lungs is by far the most common manifestation of sarcoidosis. At least 90% of affected persons experience lung involvement. Overall, about 50% develop permanent pulmonary abnormalities, and 5 to 15% have progressive fibrosis of the lung parenchyma. Sarcoidosis of the lung is primarily an interstitial lung disease in which the inflammatory process involves the alveoli, small bronchi, and small blood vessels. In acute and subacute cases, physical examination usually reveals dry crackles. At least 5% of persons suffer pulmonary arterial hypertension. The upper respiratory tract (including the larynx, pharynx, and sinuses) may be affected, which occurs in between 5 and 10% of cases. The four stages of pulmonary involvement are based on radiological stage of the disease, which is helpful in prognosis: Use of the Scadding scale only provides general information regarding the prognosis of the pulmonary disease over time. Caution is recommended, as it only shows a general relation with physiological markers of the disease and the variation is such that it has limited applicability in individual assessments, including treatment decisions.