Date Published: September 14, 2017
Publisher: Public Library of Science
Author(s): Se Jin Byun, William Han Bae, Seung Min Jung, Sang-Won Lee, Yong-Beom Park, Jason Jungsik Song, Antony Nicodemus Antoniou.
We aimed to evaluate a wide spectrum of clinical features of adult patients with spondyloarthritis (SpA) whose initial manifestation was fever, using the Assessment of SpondyloArthritis international Society (ASAS) classification criteria.
We retrospectively collected the electronic medical records of hospitalized SpA patients who initially presented to the Severance Hospital (Seoul, Korea) with fever from January 2010 to May 2016. As a control group, we also recruited one-hundred consecutive patients who were diagnosed with SpA in our outpatient clinic. Clinical features and laboratory findings were compared in two patient groups.
There were 26 patients who had fever as initial presentation of SpA (reactive arthritis 50%, undifferentiated SpA 26.9%, ankylosing spondylitis 15.4%, enteropathic arthritis 3.8%, psoriatic arthritis 3.8%). Peripheral SpA was more common in febrile SpA patients than in control SpA patients (65.4% vs 24.0%, p<0.001). Febrile SpA patients were less frequently HLA-B27 positive than control SpA patients (52.2% vs 77.0%, p<0.05). At baseline, systemic inflammatory markers were significantly higher in the febrile SpA patients (white blood cell count, 11.57 vs 7.81 cells/μL, p<0.001; erythrocyte sedimentation rate, 69.2 vs 41.0 mm/h, p<0.001; C-reactive protein, 109.6 vs 15.3 mg/L, p<0.001). The proportion of patients treated with systemic steroids was significantly higher in febrile SpA patients (57.7% vs. 11.0%, p<0.001). The proportion of patients who visited rheumatology specialty was significantly lower in febrile SpA patients than in control SpA patients (7.7% vs 59.0%, p<0.001). Various subgroups of SpA can be presented with fever as an initial manifestation. Febrile SpA patients demonstrated higher systemic inflammation and a lower chance to visit rheumatology in early stage. When evaluating febrile patients with any clinical features of SpA, clinicians are advised to consider performing SpA-focused evaluation including HLA-B27 or a simple sacroiliac joint radiograph.
Spondyloarthritis (SpA) is a collective term to refer to a group of inflammatory joint diseases characterized by the distinguishing features of axial arthritis, asymmetric peripheral arthritis, dactylitis, and enthesitis. SpA subgroups are including ankylosing spondylitis (AS), psoriatic arthritis (PsA), reactive arthritis (ReA), undifferentiated SpA, and enteropathic arthritis . According to a recently developed classification criteria by the Assessment of SpondyloArthritis international Society (ASAS), SpA is classified into axial SpA and peripheral SpA [2–4]. Axial SpA patients present characteristic symptoms of the axial skeleton (sacroiliac joints and spine), while peripheral SpA patients present symptoms of peripheral arthritis, enthesitis, and/or dactylitis [2,5].
SpA has wide range clinical manifestations from axial and peripheral musculoskeltal symptoms to non-specific systemic symptoms. It is clinically challenging to make the diagnosis of SpA in patients with non-articular symptoms. A strikingly high number of SpA patients with non-specific symptoms are misdiagnosed by clinicians, resulting in inappropriate or delayed treatment [12,17]. According to a previous study, 50% of SpA patients with anterior uveitis were diagnosed with SpA after they developed the eye symptoms . We found that only 7.7% of febrile SpA patients (Table 1) received their initial subspecialty evaluation with rheumatologists, suggesting that many clinicians do not consider SpA in the evaluation of febrile patients with extra-articular SpA symptoms. Furthermore, three febrile SpA patients (11.5%) underwent unnecessary arthroscopic surgery (Table 2), because the clinicians suspected septic arthritis in febrile SpA patients. However, we still lack a comprehensive understanding of clinical features of febrile SpA.