Familial Mediterranean fever mimicking septic arthritis

Familial Mediterranean fever with pseudo-septic arthritis: A case report and review of the literature

Familial Mediterranean fever (FMF) is a hereditary auto-inflammatory disease resulting from mutations of the MEFV gene. The disease is characterised by recurrent attacks of abdominal pain and fever. Most FMF patients develop arthritis at some point in their life usually manifesting as self-limiting monoarthritis. On very rare occasions, arthritis in FMF can mimic septic arthritis (pseudo-septic arthritis) with very similar clinical and laboratory findings. We report a case of a young male patient who presented with recurrent attacks of prolonged monoarthritis. For 2 years, he had undergone multiple admissions and operations for drainage of suspected septic joints. The synovial aspiration showed culture-negative pus with very high synovial white blood cell counts highly suggestive of septic arthritis. The patient was later found to have FMF based on homozygous M694V mutation of the MEFV gene. He was treated with colchicine monotherapy with a quick improvement of arthritis and later good control of his disease. The literature review showed very few case reports with similar presentations, most of which responded well to colchicine. FMF can mimic septic arthritis resulting in unnecessary expensive and invasive interventions and prolonged courses of antibiotics. Pseudo-septic arthritis is usually associated with M694V homozygous mutation and can complicate FMF at any time throughout the disease course. It is important to consider FMF in the differential diagnosis of septic arthritis, particularly with a family history of FMF and in patients from communities with a high prevalence of MEFV gene mutation.

Familiar Mediterranean fever mimicking septic arthritis: distinguishing with diffusion weighted imaging

FMF arthritis is generally monoarticular in origin. The affected joint is hot, tender, red and mimics septic arthritis. Conventional imaging findings, including magnetic resonance imaging (MRI) and ultrasound, do not help differentiate between these two entities. The final diagnosis depends on culture of the synovial fluid, and therefore initiation of proper drug therapy can be delayed. Diffusion weighted imaging (DWI), with its ability to detect altered water-proton mobility, might play an important role as a fast and non-invasive problem-solving tool in this setting. We here present MRI and DWI findings of a case of FMF arthritis mimicking septic arthritis.

Protracted familial mediterranean fever arthritis presenting as septic arthritis

In Familial Mediterranean Fever (FMF), arthritis is the initial symptom in 25% of patients. Although FMF arthritis is acute and self-limited, in 5% of cases protracted arthritis usually affecting large joints such as knee may occur. In this report, two cases are presented who were initially diagnosed as septic arthritis, first of which had four and the second had two synovectomy operations with the diagnosis of septic arthritis. Later on they were diagnosed as FMF with detailed history. We aimed to emphasize the importance of diagnosis of FMF, which is based mainly on history and clinical features in order to prevent unnecessary operations and suffering of the patient.