A case of familial Mediterranean fever presenting with ankylosing spondylitis: A rare case‐report.

Key Clinical Message: The association of familial Mediterranean fever and ankylosing spondylitis is rare, but it is essential to consider this diagnosis in patients with a history of FMF who develop symptoms of back pain or other rheumatologic conditions. Familial Mediterranean fever (FMF) is an inherited inflammatory disorder characterized by recurrent fever episodes, abdominal pain, and arthralgia. Ankylosing spondylitis (AS) is a chronic inflammatory disease that affects the spine's joints. The association of FMF and AS is rare. We report the case of a 22‐year‐old male patient with a history of FMF and a positive family history of FMF in his father, who presented with inflammatory back pain. The patient was found to have sacroiliitis on MRI, which is a characteristic feature of AS. The patient was negative for HLA‐B27, a genetic marker often associated with AS. This case report highlights the importance of considering AS in patients with a history of FMF who develop back pain symptoms or other rheumatologic conditions. [ABSTRACT FROM AUTHOR]