Sarcoidosis can be difficult to diagnose because the disease produces few signs and symptoms in its early stages. When symptoms do occur, they may mimic those of other disorders.
Your doctor will likely start with a physical exam, including a close examination of any skin lesions you have. He or she will also listen carefully to your heart and lungs and check your lymph nodes for swelling.
Diagnostic tests can help exclude other disorders and determine what body systems may be affected by sarcoidosis. Your doctor may recommend the following tests:
- Chest X-ray to check for lung damage or enlarged lymph nodes
- Computerized tomography (CT scan) if complications are suspected.
- Positron emission tomography (PET) scan or magnetic resonance imaging (MRI) if sarcoidosis seems to be affecting your heart or central nervous system.
- Blood tests to assess your overall health and how well your kidneys and liver are functioning.
- Lung (pulmonary) function tests to measure lung volume and how much oxygen your lungs deliver to your blood.
- Eye exam to check for vision problems that may be caused by sarcoidosis.
Your doctor may order a small sample of tissue (biopsy) be taken from a part of your body believed to be affected by sarcoidosis to look for the granulomas commonly seen with the condition. Biopsies can most easily be taken from your skin if you have skin lesions. Biopsies can also be taken from the lungs and lymph nodes if needed.