It is important to diagnose sarcoidosis in people who are suspected of having this disease - the effects of sarcoidosis can range from non-harmful to life threatening.
In many cases a doctor will perform a physical examination and review a patients medical history. Additional tests usually include blood tests, chest x ray and breathing tests. Many people displaying sarcoidosis symptoms are referred by their doctor to a pulmonologist (lung physician) - the lungs are an organ often affected by sarcoidosis.
Despite the number of tests which can be used a biopsy is the only reliable method when diagnosing sarcoidosis. A biopsy is a test which uses a sample of tissue taken from the affected area. The tissue is then tested for a disease. As sarcoidosis is a disease which affects the whole body, not just one organ, a tissue sample is usually taken from an accessible area of the body. Simple skin or conjunctival biopsy samples are normally taken under local anesthetic in a doctors surgery - the conjunctiva is a membrane which lines the eyelids inner surface.
The tests and procedures below help diagnose sarcoidosis - they can also be used to assess and monitor the disease during and after treatment.
The doctor will look for other possible causes of these symptoms during the examination.
Blood tests are used to measure the blood levels of proteins such as ACE (angiotensin converting enzyme). ACE is made by the cells in the granulomas. However, elevated or high levels of blood ACE does not always indicate sarcoidosis - other tests to diagnose sarcoidosise are also used.
Blood tests may also show elevated calcium levels and abnormalities in the liver, kidneys and bone marrow (organs which can be affected by sarcoidosis).
Chest x rays are frequently used to test for sarcoidosis and present a safe and easy method. Granulomas may appear as a shadow on an x ray. A chest x ray may also show enlarged lymph glands. Granulomas & enlarged lymph glands are both symptoms of sarcoidosis
A fiber optic bronchoscope is a slender tubular instrument used to examine the bronchial tubes. A flexible tube passes light through a fibre optic cable. The tube is inserted into the airway of the lung allowing a doctor to inspect the tissue lining.
A bronchoscope can also be used to take small samples of lung tissue & 'lung washings' (which contain lung cells) from parts of the lungs.
A saline solution (salt water) is injected into the lung. The fluid is removed using the suction action from a fibre optic bronchoscope. The fluid is then analyzed for washed out cells and other materials from alveoli (tiny air sacs) of the lung.
The pulmonary inflammation (a symptom of sarcoidosis) begins in the alveoli so washed out cells from this area can indicate sarcoidosis of the lungs.