Perinatal sacroiliitis diagnostic challenges.

Lumbo-pelvic pain is a common and non-specific problem during pregnancy and postpartum. Although perinatal pyogenic sacroiliitis is uncommon during this time, it might be difficult to distinguish from reactive sacroiliitis in women who are experiencing significant lower back and pelvic girdle pain, as the symptoms and signs are not clear and the tests are not definitive. A 34-year-old primigravida went to the emergency department with severe lower back pain radiating to the right gluteal region and down to the back of the right thigh.