Familial Mediterranean fever and spondyloarthritis: Case report, diagnostic and therapeutic difficulties

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.

Abstract

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.

Mimics of axial spondyloarthritis

PURPOSE OF REVIEW

Axial spondyloarthritis (AxSpA) is a distinct clinical entity with characteristic clinical and radiographic features; however, a multitude of other metabolic, infectious and inflammatory disorders mimic it both clinically and radiographically.

RECENT FINDINGS

We present in this review article recent updates about the various disease entities and conditions that may mimic AxSpA and how to differentiate among them. The sensitivity and specificity of MRI in diagnosing AxSpA has limitations and needs to be interpreted in the context of the clinical picture. Interestingly, some recent studies have highlighted that a relatively high prevalence of bone marrow edema on pelvic MRIs in healthy volunteers which could even be categorized as having a 'positive MRI' as defined by Assessment of Spondyloarthritis International Society. Another study revealed that a substantial proportion of patients with suspected sacroiliitis were more commonly diagnosed with diseases other than inflammatory sacroiliitis. On the basis of these reports, it is prudent to request MRIs in the appropriate clinical context and interpreted with caution taking into considerations the wide differential diagnosis of such MRI changes.

SUMMARY

Highlighting the clinical pearls that differentiate disorders suspected of having sacroiliitis will lead to earlier and correct diagnosis and management; however, one must always take into considerations the radiographic and MRI findings in addition to the clinical presentations in order to make the appropriate diagnosis.