How is scleroderma diagnosed?
After discussing your personal family medical history, your doctor will perform a thorough physical examination. In doing so, he or she will be looking for any of the symptoms mentioned above, especially thickening or hardening of the skin around the fingers and toes or discoloration of the skin. If scleroderma is suspected, tests will be ordered to confirm the diagnosis, as well as to determine the severity of the disease. These tests may include:
- Blood tests: Elevated levels of immune factors, known as antinuclear antibodies, are found in 95% of patients with scleroderma. Although these antibodies are also present in other autoimmune diseases such as lupus, testing for them in potential scleroderma patients is helpful in assisting with an accurate diagnosis.
- Pulmonary function tests: These tests are done to measure how well the lungs are functioning. If scleroderma is suspected or has been confirmed, it is important to verify whether or not it has spread to the lungs, where it can cause scar tissue formation. An X-ray or computed tomography (CT scan) may be used to check for lung damage.
- Electrocardiogram: Scleroderma can cause scarring of the heart tissue, which can lead to congestive heart failure and defective electrical activity of the heart. This test is performed to see whether the disease has affected the heart.
- Echocardiogram (an ultrasonogram of the heart): This is recommended once every 6 to 12 months to evaluate for complications like pulmonary hypertension and/or congestive heart failure.
- Gastrointestinal tests: Scleroderma can affect the muscles of the esophagus as well as the walls of the intestine. This can cause heartburn and swallowing difficulty, and can also affect the absorption of nutrients and movement of food through the intestine. An endoscopy (the insertion of a small tube with a camera on the end) is sometimes performed to view the esophagus and the intestines, and a test called manometry can measure the strength of the esophageal muscles.
- Kidney function: When scleroderma affects the kidneys, the result can be an increase in blood pressure as well as the leakage of protein into the urine. In its most serious form (called scleroderma renal crisis), a rapid increase in blood pressure may occur, resulting in kidney failure. Kidney function can be assessed through blood tests.