Clinical course and outcomes of childhood-onset granulomatosis with polyangiitis

To characterise the clinical course and outcomes of a cohort of children with granulomatosis with polyangiitis (GPA).

Retrospective cohort study of children diagnosed with GPA in a tertiary care facility from 2000-2014. All subjects met the American College of Rheumatology 1990 criteria for GPA or the 2008 European League against Rheumatism/Paediatric Rheumatology International Trials Organisation/Paediatric Rheumatology European Society criteria for GPA. Predictors of readmission were determined using univariate logistic regression. Kaplan-Meier analysis was used to demonstrate the relapse-free survival probability in follow-up.

Twenty-eight children (median age 14.7 years) were diagnosed during the study period. At presentation 14 (50%), 5 (18%), and 4 (14%) children required intensive care unit care, ventilator support, and dialysis, respectively. One-third of the children in our cohort had gastrointestinal involvement, one-quarter of whom were previously diagnosed with inflammatory bowel disease. Two-thirds of children were readmitted. Renal failure and infections accounted for most readmissions. Twenty-three (85%) patients achieved remission, however, 11 subsequently flared (median time to flare 21.5 months). Haematuria at diagnosis was significantly associated with readmission (OR 6.25). At a median follow-up of 3.3 years (range 5 months to 6 years) 10 (37%) children had chronic kidney disease (> stage 2) and none of the children died.

Children with GPA frequently have severe disease presentations including significant renal, respiratory and gastrointestinal involvement. While most children with GPA achieve remission, nearly half have subsequent relapses.