Most children with JIA managed with contemporary treatments attain inactive disease within 2 years of diagnosis and many are able to discontinue treatment. The probability of attaining remission within 5 years of diagnosis is about 50%, except for children with polyarthritis.

Methods. Eligible patients had been diagnosed by site rheumatologists (termed the "MD diagnosis") since 2004. This diagnosis was used as a reference standard for sensitivity and specificity testing of the 2 WG classification criteria. Descriptive analyses were confined to ACR-classified WG patients.Results. MD diagnoses of 117 patients (82 of whom were female) were WG (n ‫؍‬ 76), microscopic polyangiitis (n ‫؍‬ 17), ANCA-positive pauci-immune glomerulonephritis (n ‫؍‬ 5), Churg-Strauss syndrome (n ‫؍‬ 2), and unclassified vasculitis (n ‫؍‬ 17). The sensitivities of the ACR and EULAR/PRES classification criteria for WG among the spectrum of AAVs were

EULAR/PRINTO/PRES propose validated classification criteria for HSP, c-PAN, c-WG and c-TA, with substantial/almost perfect agreement with the final consensus classification or original treating physician diagnosis.

Younger age at disease onset and, perhaps, both gastrointestinal manifestations and more severe kidney disease seem to characterize the clinical profile in children with MPA compared to those with GPA. Delay in diagnosis suggests that recognition of these systemic vasculitides is suboptimal. Compared with adults, initial treatment regimens in children were comparable, but the complete reversal of female-to-male disease prevalence ratios is a provocative finding.