SLE can be difficult to diagnose. Symptoms can fluctuate and mimic those of other diseases. A doctor will make a diagnosis of SLE based on symptoms, medical history, physical exam and blood test for antinuclear antibodies. The doctor may also order other types of laboratory tests.
The American College of Rheumatology (ACR) has a classification system for helping doctors diagnose, or exclude, SLE. According to the ACR, at least four of the 11 criteria should be present for a diagnosis of...