Abstract
Introduction. Early diagnosis of spondyloarthritis (SpA) remains a serious problem in regions where brucellosis is endemic, as musculoskeletal (MSK) involvement in chronic brucellosis (ChB) is similar and can mimic SpA. The aim is to identify signs and symptoms important for the differential diagnosis of spondyloarthritis and chronic brucellosis by comparing a wide range of clinical manifestations of these diseases. Materials and methods. In a retrospective-prospective study conducted in a brucellosis-endemic region, the epidemiological characteristics and clinical features of two groups of patients meeting the ASAS (Assessment of Spondyloarthritis International Society) criteria were compared: those with SpA and those with ChB. Patients with a probable combination of these two diseases were excluded from the study. Results. The comparative analysis included 40 people with HBP who met the ASAS criteria and 139 people with SpA. ASAS criteria for peripheral SpA were identified in 85% of patients with HBP and in 30% of patients with SpA. HLA-B27 was present in 25% of patients with IBD and 71% with SpA. A positive epidemiological history was frequently recorded not only in ChB (100%) but also in SpA (38%) (p<0.001). Important distinguishing features of ChB were unilateral sacroiliitis (65% vs. 13.7% in SpA; p<0.001), predominantly mechanical back pain (47.5% vs. 5.8%, p<0.001), and polyarthritis of small joints (30% vs. 14.4%; p<0.001), with frequent involvement of upper limb joints. ChB was particularly characterized by signs of infection (95% vs. 24.4%), damage to the autonomic (75% vs. 29.5%) and peripheral (47% vs. 15.8%) nervous systems, affective disorders (47.5% vs. 6.4%) (all p<0.001), and reproductive system pathology, including obstetric pathology. Unlike SpA, MSK involvement and other manifestations of ChB did not respond adequately to NSAIDs and disappeared after antibiotic therapy. Conclusion. The study identified distinctive clinical features that may help distinguish SpA from ChB.