A rheumatologist will evaluate you through a combination of detailed questioning, physical examination, blood tests, imaging, and family history review. The physical examination will assess your range of motion, pain patterns, and joint tenderness.
Two blood tests can provide clues. One measures C-reactive protein (CRP), a marker of inflammation that is elevated in about half of people with axSpA. The other tests for the HLA-B27 gene. Up to 90% of people with axSpA carry this gene, though only a small percentage of people with the gene develop the condition.
An MRI of the pelvis can reveal inflammation in the sacroiliac joints even at early stages, which is a key sign of axSpA. Standard lumbar spine imaging may miss this area. “When a patient complains of back pain, a doctor may order an MRI of the lumbar spine that does not include imaging of the sacroiliac joints,” Dr. Danve says. “But imaging of the pelvis can show inflammation in the sacroiliac joints and is more likely to help confirm axSpA.”
Your rheumatologist will also ask about your family and medical history. AxSpA can cluster in families. “One family member has psoriasis, another has Crohn’s disease, or the patient themselves may have had a condition such as psoriasis, inflammatory bowel disease, or eye inflammation,” Dr. Danve says.
