To be or not to B27 positive: implications for the phenotypes of axial spondyloarthritis outcomes. Data from a large multiracial cohort from the Brazilian Registry of Spondyloarthritis.

BACKGROUND: There is a remarkable variability in the frequency of HLA-B27 positivity in patients with spondyloarthritis (SpA), which may be associated with different clinical presentations worldwide. However, there is a lack of data considering ethnicity and sex on the evaluation of the main clinical and prognostic outcomes in mixed-race populations. The aim of this study was to evaluate the frequency of HLA-B27 and its correlation with disease parameters in a large population of patients from the Brazilian Registry of Spondyloarthritis (RBE). METHODS: The RBE is a multicenter, observational, prospective cohort that enrolled patients with SpA from 46 centers representing all five geographic regions of Brazil. The inclusion criteria were as follow: (1) diagnosis of axSpA by an expert rheumatologist; (2) age ≥18 years; (3) classification according to ASAS axial. The following data were collected via a standardized protocol: demographic data, disease parameters and treatment historical. RESULTS: A total of 1096 patients were included, with 73.4% HLA-B27 positivity and a mean age of 44.4 (±13.2) years. Positive HLA-B27 was significantly associated with male sex, earlier age at disease onset and diagnosis, uveitis, and family history of SpA. Conversely, negative HLA-B27 was associated with psoriasis, higher peripheral involvement and disease activity, worse quality of life and mobility. CONCLUSIONS: Our data showed that HLA-B27 positivity was associated with a classic axSpA pattern quite similar to that of Caucasian axSpA patients around the world. Furthermore, its absence was associated with peripheral manifestations and worse outcomes, suggesting a relevant phenotypic difference in a highly miscegenated population.

Epidemiologic Features of Systemic Vasculitides in the Southeast Region of Brazil: Hospital-Based Survey.

BACKGROUND/OBJECTIVE: The epidemiology of vasculitis is variable in different geographic areas, and this issue has not been approached in Brazil yet. The objective of this study was to assess the frequency of vasculitis in specialized centers in Brazil. METHODS: This cross-sectional study was performed in 9 vasculitis outpatient clinics from 6 different states mainly from the Southeast and the Northeast regions of Brazil between 2015 and 2017. Diagnosis and/or classification criteria for Behçet disease (BD), Takayasu arteritis (TA), giant cell arteritis (GCA), polyarteritis nodosa (PAN), granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), eosinophilic granulomatosis with polyangiitis (EGPA), and cryoglobulinemic vasculitis (CryoVas) were used to include patients with at least 6 months of follow-up in this hospital-based survey. RESULTS: A total of 1233 patients with systemic vasculitis were included from the Southeast region. Behçet disease was the most frequent vasculitis (35.0%) followed by TA (26.4%), GPA (16.2%), PAN (5.8%), GCA (5.8%), EGPA (4.3%), MPA (3.4%), and CryoVas (3.0%). Up to 7.8% of vasculitis patients had a juvenile onset, and the frequency of vasculitides found in children and adolescents was as follows: TA (52.6%), BD (24.7%), GPA (12.4%), and PAN (10.3%). No cases of EGPA, MPA, and CryoVas were diagnosed before the age of 18 years. As a comparator, 103 vasculitis patients were included in the Northeast of Brazil where TA was found in 36.9% and BD in 31.1% of vasculitis cases. No GCA cases were found in the Northeast part of Brazil. CONCLUSIONS: Similar to the epidemiology of vasculitis in Asia, BD and TA are the most frequent vasculitis in Southeastern Brazilian referral centers.