Update on systemic vasculitides

Management of systemic vasculitis has been revolutionised over the last decade with the introduction of targeted biological agents. With an increase in both the prevalence and the recognition of vasculitis as well as the high cost of these agents, it is important to ensure their most optimal utilisation. The goals of vasculitis therapy include the induction and maintenance of remissions, preventing relapses, reducing the toxicity of therapy with the aim of reducing morbidity and mortality as well as improving the quality of life of those afflicted. This review focuses on the recent advances in the diagnosis, surveillance and treatment of these conditions.

Effect of Autoantibodies to Erythropoietin Receptor in Systemic Lupus Erythematosus with Biopsy-proven Lupus Nephritis

OBJECTIVE

We examined the clinical significance of autoantibodies to the erythropoietin receptor (EPOR) in patients with systemic lupus erythematosus (SLE) who had biopsy-proven lupus nephritis (LN).

METHODS

Forty-six Japanese patients with SLE with LN who had undergone renal biopsy during 1993-2014 were enrolled in this study and followed for a mean of 83 months. Sera from those patients were screened for anti-EPOR antibodies using ELISA.

RESULTS

Anti-EPOR antibodies were detected in 18 (39%) of the 46 patients with SLE with anemia. Anti-EPOR antibodies were associated with low hemoglobin concentrations and reticulocytopenia. In addition, anti-EPOR antibodies were positively correlated with SLE disease activity, even though serum levels of the complement factors 3 and 4 did not differ between the 2 groups. In patients with International Society of Nephrology/Renal Pathology Society 2003 class IV LN, anti-EPOR antibodies were associated with active lesions including cellular crescents in glomeruli. Decrease in renal function was more frequently observed in patients without complete or partial renal response than in patients with it, and serum levels of the antibodies as well as renal response to treatment were significant risk factors for progression of renal dysfunction.

CONCLUSION

The present study suggests that anti-EPOR antibodies might be involved in overall disease activity and active renal lesions, as well as in the impaired erythropoiesis in patients with SLE with LN. Further, the levels of anti-EPOR antibodies may be an additional predictor for renal injury.

The role of parvovirus B19 in the pathogenesis of autoimmunity and autoimmune disease

Human parvovirus B19 is a single-stranded DNA virus which preferentially targets the erythroblasts in the bone marrow. B19 infection commonly causes erythema infectiosum, arthralgia, fetal death, transient aplastic crisis in patients with shortened red cell survival, and persistent infection in people who are immunocompromised. Less common clinical manifestations include atypical skin rashes, neurological syndromes, cardiac syndromes, and various cytopenias. B19 infection has also been associated with development of a variety of different autoimmune diseases, including rheumatological, neurological, neuromuscular, cardiovascular, haematological, nephrological and metabolic. Production of a variety of autoantibodies has been demonstrated to occur during B19 infection and these have been shown to be key to the pathogenesis of the particular disease process in a significant number of cases, for example, production of rheumatoid factor in cases of B19-associated rheumatoid arthritis and production of anti-glutamic acid decarboxylase (GAD) in patients with B19-associated type 1 diabetes mellitus. B19 infection has also been associated with the development of multiple autoimmune diseases in 12 individuals. Documented mechanisms in B19-associated autoimmunity include molecular mimicry (IgG antibody to B19 proteins has been shown to cross react with a variety of recognised human autoantigens, including collagen II, keratin, angiotensin II type 1 receptor, myelin basic protein, cardiolipin, and platelet membrane glycoprotein IIb/IIIa), B19-induced apoptosis with presentation of self-antigens to T lymphocytes, and the phospholipase activity of the B19 unique VP1 protein.

Celiac disease autoimmunity and hip fracture risk: findings from a prospective cohort study

The impact of celiac disease autoimmunity on bone health is unclear. We investigated the associations of seropositivity for tissue transglutaminase antibodies (tTGA) and endomysial antibodies (EMA) with incident hip fractures using data from a prospective cohort study, Mini-Finland Health Survey. Baseline serum samples, taken in 1978-80, were tested for tTGA and EMA. Incident hip fractures up to the year 2011 were ascertained from a national hospitalization register. Associations between seropositivity and hip fractures were modeled using Cox proportional hazards regression adjusted for age, sex, body mass index, vitamin D, gamma-glutamyl transferase, smoking, and self-rated health. Our analyses were based on 6919 men and women who had no record of celiac disease or hip fracture before the study baseline. A total of 382 individuals had a hip fracture during a median follow-up of 30 years. Compared with the tTGA-negative individuals (n = 6350), tTGA-positive participants (n = 569; with hip fracture, n = 51) had a higher risk of hip fractures (hazard ratio [HR] = 1.59, 95% confidence interval [CI] 1.17, 2.14). The findings were similar for another tTGA test (n 200; with hip fracture, n = 26; HR = 2.23, 95% CI 1.49, 3.34). We found no evidence for an association between EMA positivity and hip fracture risk (HR = 0.92, 95% CI 0.34, 2.47; n = 74; with hip fracture, n = 4). In our prospective population-based study of Finnish adults, seropositivity for tTGA was associated with an increased hip fracture risk.

Disease factors in early rheumatoid arthritis are associated with differential risks for cardiovascular events and mortality depending on age at onset: a 10-year observational cohort study

OBJECTIVE

To investigate, within the first 2 years of diagnosis with rheumatoid arthritis (RA), associations between disease-related measures and cardiovascular disease (CVD) and mortality in patients with RA onset before and after 65 years of age.

METHODS

The study population (n = 741; 67.5% women) was derived from the Better Anti-Rheumatic Pharmaco Therapy (BARFOT) early RA cohort, recruited 1993-1999. The mean age was 55 years (SD 14.7). The outcomes were incident CVD events and all-cause mortality until 2010. Area under the curve (AUC) for disease measures at inclusion, 1 and 2 years, and decrease in measures after 1 year were calculated.

RESULTS

In all, 177 CVD events and 151 deaths occurred over 10 years of observation. In adjusted Cox regression analyses, seropositivity for rheumatoid factor (RF) or anticitrullinated protein antibodies (ACPA); white blood (cell) count at diagnosis; and AUC of C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and visual analog scale (VAS)-pain were associated with higher CVD risk among patients with disease onset before 65 years of age. Among patients with disease onset after 65 years, larger decreases in CRP, ESR, health assessment questionnaire (HAQ), and use of methotrexate decreased CVD risk, whereas use of glucocorticoids heightened CVD risk. AUC of CRP, ESR, HAQ, and HAQ after 2 years was related to risk of death in both age groups. Seropositivity and AUC for VAS-pain in the younger group and use of glucocorticoids in the elderly were associated with poorer survival.

CONCLUSION

Early treatment of RA may improve longterm outcomes. Presence of RF or ACPA associates with CVD and mortality among RA patients with disease onset before 65 years. Age stratification may improve evaluation of risk for CVD and mortality in early RA.