Question

A 27-year-old man presents with lower back pain and stiffness for 6 months, worse in the morning, improving with exercise. Which investigation is most useful initially to support a diagnosis of ankylosing spondylitis?

Accepted Answer

Spine MRI (sacroiliac joints)

Answer

Rheumatoid factor test

Answer

Serum uric acid

Answer

X-ray of the lumbar spine alone

Answer

HLA-B27 test alone

Practice question

A 27-year-old man presents with lower back pain and stiffness for 6 months, worse in the morning, improving with exercise. Which investigation is most useful initially to support a diagnosis of ankylosing spondylitis?