AB0938 Chikungunya and Bilateral Sacroiliitis – is There a Link?
Authors: M.K. Nisar, C.I. Packianathan
Journal: Annals of the Rheumatic Diseases (2015)

<h3>Background</h3> Chikungunya (CKG) virus is an arthritogenic mosquito-transmitted alphavirus which manifests as a febrile illness and often progresses to severe and incapacitating polyarthralgia. Several reports have demonstrated persistent polyarthritis akin to seronegative peripheral arthropathy. However, to our knowledge, imaging confirmed axial disease has not been described in this context. <h3>Objectives</h3> We report a case of an Asian lady who developed axial spondyloarthropathy after contracting CKG whilst visiting India during an outbreak. <h3>Methods</h3> The patient was assessed by history, physical examination, imaging and serological markers. <h3>Results</h3> A 51-year-old previously healthy woman developed CKG infection whilst travelling to India during a regional outbreak in an endemic area. It began with classic symptoms of acute fever and generalized myo-arthralgia followed by residual pain primarily affecting the small joints and to a lesser extent pain in the lumbar region and both hips. Initial investigations a were unremarkable. Dengue NS1 antigen and Dengue IgM were negative. Thyroid function tests and bone profile were normal. Serum 25-OH Vitamin D was within the reference range. Xrays of small joints at the time showed soft tissue swelling in wrists and ankles. Xray of LS spine showed minor degenerative change in L4/5and L5/S1. X ray of sacro-iliac joints was normal. The patient was commenced on regular NSAIDS. Following graded physical activity over six months, her symptoms improved apart from mild episodic fatigue and lethargy. A year later, she presented to our Rheumatology department with a 2-month history of severe intermittent pain in both hips and buttocks. She also experienced low back pain and pain in both shoulders. The pain in the hips and buttocks was intermittent and alternated between the two sides. She also experienced widespread myalgia, malaise and fatigue. Investigations at the time of presentation showed a normal FBC, U&amp;E, CRP, LFT, glucose, bone profile including Vitamin D, TFT, negative ANA, anti CCP antibody, RF and HLA B27. Her Chikungunya IgG was positive. Surprisingly bone scan showed increased uptake in inferior aspect of the sacro-iliac joints bilaterally with the right involved more than the left. An MRI scan confirmed bilateral sacro-ilitis with marked oedema across the inferior aspects of the joints. The patient was commenced on regular NSAIDS and physiotherapy with good symptomatic relief. <h3>Conclusions</h3> There are numerous reports suggesting CKG arthritis can mimic rheumatoid arthritis. However, to our knowledge this is the first report of CKG associated axial spondyloarthropathy. While most cases of chikungunya arthropathy recover within several weeks, up to 12% retain residual joint symptoms for months to years. At present, not much is known about the underlying immunopathophysiological processes by which chikungunya virus causes arthritis. A recent article suggested that chronic musculoskeletal tissue pathology is associated with persistent CKG infection and controlled by adaptive immune responses. However, as the outbreaks of this debilitating disease become global, a high index of suspicion is required for early diagnosis and management – particularly in centers with little exposure to this patient cohort. <h3>Disclosure of Interest</h3> None declared