No abstract

Objectives Coxiella and Bartonella sp. display particular tropism for endothelial or endocardial tissues and an abnormal host response to infections with induced autoimmunity. We aimed, through a case series combined with a comprehensive literature review, to outline characteristics of Coxiella and Bartonella infections presenting as systemic vasculitis. Methods We retrospectively included cases of definite Coxiella and Bartonella infections presenting with vasculitis features and performed a comprehensive literature review. Results Six cases of Bartonella infections were added to 18 cases from literature review. Causative pathogens were mainly B. henselae. Bartonella infection mimicked anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis in 83% with PR3-ANCA and presented as cryoglobulinemic vasculitis in 8%. Glomerulonephritis was present in 92%, and 88% had endocarditis. Complement fractions were low in 82% and rheumatoid factor positive in 85%. Kidney biopsies showed cell proliferation, mostly crescentic, with pauci-immune glomerulonephritis in 29%. Outcome was favorable, with the use of antibiotics alone in one third. Five cases of Coxiella infections were added to 16 from literature review. Sixteen had small-vessel vasculitides, mainly cryoglobulinemia vasculitis in 75%. One patient had polyarteritis nodosa-like vasculitis and four large-vessel vasculitis. Outcome was good except for one death. A highly sensitive next generation sequencing analysis on 3 Coxiella and 2 Bartonella-related vasculitides biopsies did not find any bacterial DNA. Conclusion Coxiella and Bartonella are both able to induce vasculitis but display distinct vasculitis features. Bartonella mimics PR3-ANCA-associated vasculitis in the setting of endocarditis, whereas Coxiella may induce vasculitis involving all vessel sizes.

IFNα and anti-IFNα autoantibodies have been implicated in susceptibility both for systemic lupus erythematosus (SLE) and viral infection. We aimed to analyze the SLE disease phenotype and risk for infection associated with anti-IFN-α IgG autoantibodies in SLE patients In this multidisciplinary retrospective single referral center study, all consecutive patients with SLE admitted between January 1st and November 30th 2020 were considered. All subjects fulfilled the ACR/EULAR 2019 criteria for SLE. Anti-IFNα IgG autoantibodies were quantified at admission by ELISA. Demographic, medical history, laboratory, treatment, and outcome data were extracted from electronic medical records using a standardized data collection form. 180 patients [female 87.2%, median age of 44.4 (34–54.2) years] were included. The median disease duration was 10 years [4–20] with a median SLEDAI score of 2 [0–4] at study time. Fifty-four (30%) patients had a past-history of lupus nephritis. One hundred and forty-four (80%) had received long-term glucocorticoids and 99 (55%) immunosuppressive drugs. Overall, 127 infections—mostly bacterial and viral—were reported in 95 (52.8%) patients. Twenty SLE patients (11.1%) had positive anti-IFNα IgG autoantibodies with a titer ranging from 10 to 103 UA/mL. Age, sex, SLE phenotype and treatment did not significantly differ between SLE patients with or without anti-IFNα. Infection rate was similar in both groups except for tuberculosis which was more frequent in patients with anti-IFNα (20% vs. 3.1%, p = 0.01). The prevalence of autoantibodies against IFNα is high in SLE and associated with a higher frequency of tuberculosis.

ObjectivesWe aimed to compare disease characteristics between primary Sjögren’s syndrome (pSS) patients of African ancestry (AA) and Caucasian ancestry.MethodsWe conducted a retrospective, case–control study in a French national and European referral centre for pSS. All patients with pSS of AA were matched with two Caucasians patients having similar follow-up duration. We explored clinical and biological parameters associated with a cumulative EULAR Sjögren’s Syndrome Disease Activity Index (cumESSDAI ≥5) (consisting of individual clinESSDAI domain maximum throughout follow-up).ResultsWe identified 74 patients of AA matched with 148 Caucasian. Median age at pSS diagnosis was younger in AA patients (43 years (IQR 33–51) vs 56 years (44.8–59.2), p<0.001). AA patients presented higher median titre of gammaglobulins (18.5 g/L (IQR 15–22.8) vs 13.4 g/L (9.9–16.9), p<0.001), more frequently positive for anti-SSA (88% vs 72%, p=0.007) and anti-RNP (11% vs 2.7%, p=0.023) antibodies. During the follow-up (median: 6 years (IQR 2–11)), AA patients presented more systemic complications: arthritis, myositis, interstitial lung disease, lymphadenopathy, central nervous system involvement. Median cumESSDAI score was higher in AA patients (7.5 (IQR 3.2–16.0) vs 4.0 (IQR 2.0–9.0), p=0.002). Interestingly, in multivariate analyses, factors associated with disease activity were sub-Saharan AA (OR 2.65 (95% CI 1.06 to 6.94)), rheumatoid factor (OR 2.50 (95% CI 1.28 to 4.96)) and anti-RNP positivity (OR 11.1 (95% CI 1.88 to 212)).ConclusionPatients of AA display higher disease activity with a hallmark of higher B-cell activation. Studies to investigate biological drivers behind such differences are needed.