Factors predicting the severity of gastrointestinal involvement in children with IgA vasculitis? A Turkish multicenter cohort study.

Gastrointestinal (GI) involvement of IgA vasculitis (IgAV) has various clinical presentations from isolated abdominal pain to severe gastrointestinal bleeding. The aim of this study is to determine the incidence of GI involvement in children with IgAV and identify the predictors of severe GI involvement. Medical records of IgAV patients with GI involvement from 30 centers in Türkiye between 2014 and 2024 were retrospectively reviewed. Patients were classified into two groups according to the severity of GI presentations: Group 1 consisted of mild GI involvement, while Group 2 had severe GI involvement. Severe GI involvement was observed in 476 (42%) out of 1131 patients. A significant postpandemic (after March 2020) increase in GI involvement was observed (p < 0.001). Abdominal pain as an initial symptom, vomiting, purpuric rash on upper extremities and trunk, and kidney involvement were more frequent in Group 2 than in Group 1 (all p < 0.01). Leukocytosis, neutrophilia, thrombocytosis, increased C-reactive protein (CRP) level and neutrophil-to-lymphocyte ratio (NLR), and decreased serum total protein and albumin levels were detected more frequently in Group 2 (all p < 0.01). In multivariate regression analysis, thrombocytosis, elevated NLR and CRP, hypoalbuminemia, abdominal pain preceding rash, vomiting, and upper extremity rash were associated with severe GI involvement (all p < 0.05). ROC analyses identified the following optimal cut-off values for predicting severe GI involvement: WBC > 12.90 10^3/µL, ANS > 7.81 103/µL, NLR > 3.09, PLT > 404 103/µL, CRP > 20 mg/L, plasma albumin ≤ 4 g/dL.

Conclusion

Abdominal pain preceding rash, purpuric rash on upper extremities, vomiting, thrombocytosis, hypoalbuminemia, increased NLR, and high CRP may predict severe GI involvement in children with IgAV.