Reactive Arthritis
Diagnosis

Your doctor will begin by recording your complete medical history, including a description of your symptoms. You also will undergo a physical examination to check for any physical signs of the disease. Although the cause is not completely understood, a gene called HLA-B27 has been shown to increase a person's chance of developing the condition after a urogenital or intestinal infection. An estimated 75 percent of people with reactive arthritis have this gene.