Objectives To validate the previously proposed classifi cation criteria for Henoch-Schönlein purpura (HSP), childhood polyarteritis nodosa (c-PAN), c-Wegener granulomatosis (c-WG) and c-Takayasu arteritis (c-TA). MethodsStep 1: retrospective/prospective webdata collection for children with HSP, c-PAN, c-WG and c-TA with age at diagnosis ≤18 years.Step 2: blinded classifi cation by consensus panel of a representative sample of 280 cases.Step 3: statistical (sensitivity, specifi city, area under the curve and κ-agreement) and nominal group technique consensus evaluations. Results 827 patients with HSP, 150 with c-PAN, 60 with c-WG, 87 with c-TA and 52 with c-other were compared with each other. A patient was classifi ed as HSP in the presence of purpura or petechiae (mandatory) with lower limb predominance plus one of four criteria: (1) abdominal pain; (2) histopathology (IgA); (3) arthritis or arthralgia; (4) renal involvement. Classifi cation of c-PAN required a systemic infl ammatory disease with evidence of necrotising vasculitis OR angiographic abnormalities of medium-/small-sized arteries (mandatory criterion) plus one of fi ve criteria: (1) skin involvement; (2) myalgia/ muscle tenderness; (3) hypertension; (4) peripheral neuropathy; (5) renal involvement. Classifi cation of c-WG required three of six criteria: (1) histopathological evidence of granulomatous infl ammation; (2) upper airway involvement; (3) laryngo-tracheo-bronchial involvement; (4) pulmonary involvement (x-ray/CT); (5) antineutrophilic cytoplasmic antibody positivity; (6) renal involvement. Classifi cation of c-TA required typical angiographic abnormalities of the aorta or its main branches and pulmonary arteries (mandatory criterion) plus one of fi ve criteria: (1) pulse defi cit or claudication; (2) blood pressure discrepancy in any limb; (3) bruits; (4) hypertension; (5) Paediatric Rheumatology European Society propose validated classifi cation criteria for HSP, c-PAN, c-WG and c-TA with high sensitivity/specifi city. INTRODUCTIONIn 1990 the American College of Rheumatology (ACR) proposed classifi cation criteria for patients with vasculitides 1-5 by analysing 807 adults patients with different form of vasculitis: 85 with Henoch-Schönlein purpura (HSP), 118 with polyarteritis nodosa (PAN), 85 with Wegener granulomatosis (WG), 63 with Takayasu arteritis (TA) and 456 with other vasculitides (Churg-Strauss, hypersensitivity, giant cell arteritis and other unspecifi ed forms). 6 Patients with each specifi c vasculitis were compared with all the remaining diseases grouped into a single control category.The ACR criteria for HSP (sensitivity 87.1%, specifi city 87.7%) require the presence of at least two of the following: (1) age ≤20 years at disease onset; (2) palpable purpura; (3) acute abdominal pain; (4) biopsy showing granulocytes in the walls of small arterioles/venules. 1 The ACR criteria for PAN (sensitivity 82.2%, specifi city 86.6%) require at least three of the 10 following criteria: (1) granulocyte or mixed leucocyte infi ...

Results. Ten patients with systemic-onset JIA exhibited a dramatic response to anakinra and were classified as complete responders. Eleven patients had an incomplete response or no response, and 1 patient could not be classified in terms of response. Compared with patients who had an incomplete response or no response, complete responders had a lower number of active joints (P ‫؍‬ 0.02) and an increased absolute neutrophil count (P ‫؍‬ 0.02). In vitro IL-1␤ and IL-18 secretion in response to various stimuli was not increased and was independent of treatment efficacy. Likewise, secretion of IL-1Ra by monocytes from patients with systemic-onset JIA was not impaired. An overall low level of IL-1␤ secretion upon exposure to exogenous ATP was observed, unrelated to treatment responsiveness or disease activity.Conclusion. Two subsets of systemic-onset JIA can be identified according to patient response to IL-1 blockade. The 2 subsets appear to be characterized by some distinct clinical features. In vitro secretion of IL-1␤ and IL-18 by monocytes from patients with systemic-onset JIA is not increased and is independent of both treatment outcome and disease activity.

Objective. To examine the synthesis, processing, and secretion of interleukin-1␤ (IL-1␤), as well as the clinical and biologic effects of IL-1 blockade, in patients with chronic infantile neurologic, cutaneous, articular (CINCA) syndrome and Muckle-Wells syndrome (MWS), in an effort to understand the molecular mechanisms linking mutations of the CIAS1 gene and IL-1␤ hypersecretion, and the underlying response to IL-1 receptor antagonist (IL-1Ra).Methods. Six patients with CINCA syndrome or MWS were treated with IL-1Ra and followed up longitudinally. Monocytes obtained from the patients and from 24 healthy donors were activated with lipopolysaccharide (LPS) for 3 hours, and intracellular and secreted IL-1␤ levels were determined by Western blotting and enzyme-linked immunosorbent assay before and after exposure to exogenous ATP.Results. LPS-induced IL-1␤ secretion was markedly increased in monocytes from patients with CIAS1 mutations. However, unlike in healthy subjects, secretion of IL-1␤ was not induced by exogenous ATP. Treatment with IL-1Ra resulted in a dramatic clinical improvement, which was paralleled by an early and strong down-regulation of LPS-induced IL-1␤ secretion by the patients' cells in vitro.Conclusion. Our results showed that the requirements of ATP stimulation for IL-1␤ release observed in healthy individuals are bypassed in patients bearing CIAS1 mutations. This indicates that cryopyrin is the direct target of ATP and that the mutations release the protein from the requirement of ATP for activation. In addition, the dramatic amelioration induced by IL-1Ra treatment is at least partly due to the strong decrease in IL-1␤ secretion that follows the first injections of the antagonist. These findings may have implications for other chronic inflammatory conditions characterized by increased IL-1␤.

Results. Raynaud's phenomenon was the most frequent symptom, followed by skin induration in ϳ75% of patients. Musculoskeletal symptoms were present in one-third of patients, and the most frequently involved internal organs were respiratory and gastrointestinal, while involvement of renal, cerebral, and cardiovascular systems was extremely rare. Antinuclear antibodies were present in the sera of 81% of patients. Antitopoisomerase I (Scl-70) and anticentromere antibodies were found to be positive in 34% and 7.1% of patients, respectively. Involvement of the respiratory, gastrointestinal, and cardiovascular systems was more frequent and occurred earlier in patients who died than in those who survived. Compared with the adult form, juvenile SSc appears to be less severe, with the involvement of fewer internal organs, particularly at the time of diagnosis, and has a less characterized immunologic profile.Conclusion. This study provides information on the largest collection of patients with juvenile SSc ever reported. Juvenile SSc appears to be less severe than in adults because children have less internal organ involvement, a less specific autoantibody profile, and a better long-term outcome.