Despina Eleftheriou

Utility and safety of rituximab in pediatric autoimmune and inflammatory CNS disease

Objective: To assess the utility and safety of rituximab in pediatric autoimmune and inflammatory disorders of the CNS. Methods: Multicenter retrospective study. Results: A total of 144 children and adolescents (median age 8 years, range 0.7–17; 103 female) with NMDA receptor (NMDAR) encephalitis (n = 39), opsoclonus myoclonus ataxia syndrome (n = 32), neuromyelitis optica spectrum disorders (n = 20), neuropsychiatric systemic lupus erythematosus (n = 18), and other neuroinflammatory disorders (n = 35) were studied. Rituximab was given after a median duration of disease of 0.5 years (range 0.05–9.5 years). Infusion adverse events were recorded in 18/144 (12.5%), including grade 4 (anaphylaxis) in 3. Eleven patients (7.6%) had an infectious adverse event (AE), including 2 with grade 5 (death) and 2 with grade 4 (disabling) infectious AE (median follow-up of 1.65 years [range 0.1–8.5]). No patients developed progressive multifocal leukoencephalopathy. A definite, probable, or possible benefit was reported in 125 of 144 (87%) patients. A total of 17.4% of patients had a modified Rankin Scale (mRS) score of 0–2 at rituximab initiation, compared to 73.9% at outcome. The change in mRS 0–2 was greater in patients given rituximab early in their disease course compared to those treated later. Conclusion: While limited by the retrospective nature of this analysis, our data support an off-label use of rituximab, although the significant risk of infectious complications suggests rituximab should be restricted to disorders with significant morbidity and mortality. Classification of evidence: This study provides Class IV evidence that in pediatric autoimmune and inflammatory CNS disorders, rituximab improves neurologic outcomes with a 7.6% risk of adverse infections.

Biologic therapy in refractory chronic non-bacterial osteomyelitis of childhood

OBJECTIVE To date there is no uniformly effective treatment for either chronic recurrent multifocal osteomyelitis (CRMO) or synovitis, acne, pustulosis, hyperostosis and osteitis (SAPHO) syndrome. We report on our clinical experience of using biologic therapy to treat children with these conditions. METHODS Retrospective descriptive case series of four children with refractory disease treated with biologics. Disease activity was assessed at predetermined time points (T = 0, T = 6 weeks and T = 12 months after the start of biologic therapy, and at latest follow-up) using a combination of clinical examination and radiological findings: a 10 cm pain and physician visual analogue scale; the Childhood Health Assessment Questionnaire as an assessment of disability; and changes in markers of systemic inflammation. RESULTS There was an initial improvement in all parameters assessed for all three children treated with TNF-alpha blockade, although the third case had to discontinue the therapy due to a suspected (but unconfirmed) fungal skin infection. Anakinra treatment alleviated the symptoms in the fourth patient at 6 weeks, but there was no sustained response to treatment at 1-year follow-up. CONCLUSION We present our preliminary experience of using biological therapies to treat children with CRMO and SAPHO in conjunction with other immunosuppression. Further studies are needed to establish the role of these therapies in refractory CRMO and SAPHO.

Medium-size-vessel vasculitis

Medium-size-artery vasculitides do occur in childhood and manifest, in the main, as polyarteritis nodosa (PAN), cutaneous PAN and Kawasaki disease. Of these, PAN is the most serious, with high morbidity and not inconsequential mortality rates. New classification criteria for PAN have been validated that will have value in epidemiological studies and clinical trials. Renal involvement is common and recent therapeutic advances may result in improved treatment options. Cutaneous PAN is a milder disease characterised by periodic exacerbations and often associated with streptococcal infection. There is controversy as to whether this is a separate entity or part of the systemic PAN spectrum. Kawasaki disease is an acute self-limiting systemic vasculitis, the second commonest vasculitis in childhood and the commonest cause of childhood-acquired heart disease. Renal manifestations occur and include tubulointerstitial nephritis and renal failure. An infectious trigger and a genetic predisposition seem likely. Intravenous immunoglobulin (IV-Ig) and aspirin are effective therapeutically, but in resistant cases, either steroid or infliximab have a role. Greater understanding of the pathogenetic mechanisms involved in these three types of vasculitis and better long-term follow-up data will lead to improved therapy and prediction of prognosis.

Anti-Neutrophil Cytoplasmic Antibodies Stimulate Release of Neutrophil Microparticles

The mechanisms by which anti-neutrophil cytoplasmic antibodies (ANCAs) may contribute to the pathogenesis of ANCA-associated vasculitis are not well understood. In this study, both polyclonal ANCAs isolated from patients and chimeric proteinase 3-ANCA induced the release of neutrophil microparticles from primed neutrophils. These microparticles expressed a variety of markers, including the ANCA autoantigens proteinase 3 and myeloperoxidase. They bound endothelial cells via a CD18-mediated mechanism and induced an increase in endothelial intercellular adhesion molecule-1 expression, production of endothelial reactive oxygen species, and release of endothelial IL-6 and IL-8. Removal of the neutrophil microparticles by filtration or inhibition of reactive oxygen species production with antioxidants abolished microparticle-mediated endothelial activation. In addition, these microparticles promoted the generation of thrombin. In vivo, we detected more neutrophil microparticles in the plasma of children with ANCA-associated vasculitis compared with that in healthy controls or those with inactive vasculitis. Taken together, these results support a role for neutrophil microparticles in the pathogenesis of ANCA-associated vasculitis, potentially providing a target for future therapeutics.

Disease activity assessment in childhood vasculitis: development and preliminary validation of the Paediatric Vasculitis Activity Score (PVAS)

Background Rare chronic childhood vasculitides lack a reliable disease activity assessment tool. With emerging new treatment modalities such a tool has become increasingly essential for both clinical practice and therapeutic trials to reproducibly quantify change in disease state. Objective To develop and validate a paediatric vasculitis activity assessment tool based on modification of the Birmingham Vasculitis Activity Score (BVASv.3). Methods A paediatric vasculitis registry was reviewed to identify clinical features missing in the BVASv.3. A modified nominal group technique was used to develop a working version of the Paediatric Vasculitis Activity Score (PVAS). Prospective validation provided tool reliability, reproducibility and responsiveness to change. Training of assessors was done according to the BVAS principles. Results BVAS items were redefined (n=22) and eight paediatric items added in Cutaneous (n=4), Cardiovascular (n=3) and Abdominal (n=1) sections. The final PVAS has 64 active items in nine categories. The principles of new/worse and persistently active disease were retained as were the overall score and weighting of categories. The median PVAS in 63 children with systemic vasculitis was 4/63 (0–38/63). There was a high interobserver agreement for the overall as well as for subsystem scores (linear-weighted-κ ≥0.87). PVAS correlated with physicians global assessment (p<0.01); treatment decision (p=<0.01) and erythrocyte sedimentation rate (ESR) (p=0.01). In response to treatment, 15/19 patients assessed demonstrated a significant fall in PVAS (p=0.002), with good agreement among assessors for this change. Conclusions The PVAS validity in children with systemic vasculitis was demonstrated. Like the BVAS, we anticipate that the PVAS will provide a robust tool to objectively define disease activity for clinical trials and future research.

Investigation of childhood central nervous system vasculitis: magnetic resonance angiography versus catheter cerebral angiography

Aim  We compared the clinical utility of magnetic resonance angiography (MRA) to catheter cerebral angiography (CA) in the investigation of children with suspected central nervous system (CNS) vasculitis.

Systemic Polyarteritis Nodosa in the Young: A Single-Center Experience Over Thirty-Two Years

OBJECTIVE Polyarteritis nodosa (PAN) is a rare disease of childhood. The aims of this study were to describe the clinical features, treatment, and outcome of systemic childhood PAN and to identify predictors of relapse. METHODS A single-center retrospective medical records review of children with PAN fulfilling the European League Against Rheumatism (EULAR)/Paediatric Rheumatology European Society (PRES)/Paediatric Rheumatology International Trials Organisation (PRINTO) classification criteria who were seen over a 32-year period was performed. Data on demographic and clinical features, treatments, relapses (recurrence of clinical signs/symptoms or occurrence of new symptoms after initial remission requiring escalation or resumption of immunosuppressive therapy), and deaths were recorded. A disease activity score was retrospectively assigned using the Paediatric Vasculitis Activity Score (PVAS) instrument. Cox regression analysis was used to identify significant predictors of relapse. RESULTS Sixty-nine children with PAN were identified; 55% were male, and their median age was 8.5 years (range 0.9-15.8 years). Their clinical features at presentation were fever (87%), myalgia (83%), skin (88%), renal (19%), severe gastrointestinal (GI) (10%), and neurologic (10%) involvement. The PVAS at presentation was 9 of 63 (range 4-24). Histopathologic analysis of the skin showed necrotizing vasculitis in biopsy samples from 40 of 50 children. Results of selective visceral arteriography suggested the presence of PAN in 96% of patients. Treatment included cyclophosphamide and corticosteroids (83%), plasma exchange (9%), and biologic agents (after 2002; 13%). The relapse rate was 35%, and the mortality rate was 4%. Severe GI involvement was associated with increased risk of relapse (P = 0.031), while longer time to induce remission (P = 0.022) and increased cumulative dose of cyclophosphamide (P = 0.005) were associated with lower relapse risk. CONCLUSION Childhood PAN is a severe inflammatory disease of insidious onset and variable clinical presentation. Relapses occurred more frequently in those with severe GI involvement. A higher cumulative dose of cyclophosphamide was associated with a lower risk of relapse.

Vasculitis in children

Primary systemic vasculitides of the young are relatively rare diseases, but can have a significant morbidity and mortality. The purpose of this review is to provide an overview of the paediatric vasculitides. Vasculitides that predominantly affect children will be considered in more detail than vasculitic diseases that although are seen in children affect adults more commonly, such as the ANCA associated vasculitides. New classification criteria for childhood vasculitis have recently been proposed and are currently undergoing validation. Epidemiological clues continue to implicate infectious triggers in Kawasaki Disease and Henoch Schönlein purpura. Several genetic polymorphisms have now been described in the vasculitides that may be relevant in terms of disease predisposition or development of disease complications. Treatment regimens continue to improve, with the use of different immunosuppressive medications and newer therapeutic approaches such as biologic agents. However new challenges are looming in regards to the role of inflammation in endothelial health and the long term cardiovascular morbidity for children with primary systemic vasculitis. International multicenter collaboration is of utmost importance in order for us to further advance our understanding and improve the treatment and outcome of systemic vasculitis in the young.

Deficiency of Adenosine Deaminase Type 2: A Description of Phenotype and Genotype in Fifteen Cases

To describe the clinical features, genotype, and treatment in a series of subjects with confirmed adenosine deaminase 2 (ADA2) deficiency.

Endothelial injury and repair in systemic vasculitis of the young

OBJECTIVE Endothelial injury is central to the pathogenesis of vasculitis. The purpose of this study was to assess how indices of endothelial injury and repair change during different stages of disease activity in children with primary systemic vasculitis (PSV). METHODS Fifty children with PSV, 17 children with nonvasculitic inflammatory diseases (pediatric inflammatory disease controls), 35 healthy age- and sex-matched pediatric controls, and 27 healthy adult controls were included in the study. Biomarkers examined were endothelial microparticles (EMPs), circulating endothelial cells (CECs), angiogenic growth factors, and endothelial progenitor cells (EPCs). EMP binding to annexin V, EMPs expressing CD144 or E-selectin, and EPCs expressing vascular endothelial growth factor receptor 2 (VEGFR-2), CD133, and CD34 were examined by flow cytometry. CECs were enumerated using immunomagnetic bead extraction techniques, and VEGF and angiopoietin 2 (Ang-2) were measured by enzyme-linked immunosorbent assay. RESULTS Levels of CD144+ EMPs, CECs, VEGF, and EPCs were all significantly elevated in children with active vasculitis as compared with healthy children, and the levels declined with remission-inducing therapy in the individual patients. Treatment-naive patients with active disease had significantly higher levels of VEGF and Ang-2 than did those with active disease who were receiving treatment, although the levels of CECs and EMPs remained high in both of these groups. CONCLUSION Elevation of the levels of CECs, EMPS, EPCs, VEGF, and Ang-2 occurs during active vasculitis in children. EPC responses to active vasculitis are different in children as compared with that observed in adults with vasculitis, and both CECs and EMPs can be used to monitor disease activity in children with vasculitis.