Magnetic resonance enterography in diagnosing and monitoring of adult-onset IgA vasculitis (Henoch-Schönlein purpura) with gastro-intestinal involvement: Report of two cases

Background: IgA vasculitis (IgAV) is a small vessel vasculitis affecting children and, less commonly, adults; in the latter, gastro-intestinal (GI) involvement occurs in up to 50% of cases. Diagnosis is made with computed tomography, ultrasonography and endoscopy, but no data have been to date published about the use of magnetic resonance enterography (MRE). Aim of the work: This work reports two leading cases of adult-onset IgAV with GI involvement in which MRE was used at baseline and during follow-up. Case report: The first case was for a 55-year old male presenting with microhematuria and elevated markers of inflammation at admission. MRE evidenced jejunum and proximal ileum diffuse and asymmetric thickening and hypervascularization. Leukocytoclastic vasculitis and glomerulonephritis with IgA deposit were evidenced at skin and renal biopsy, respectively. At one-year follow-up, a relapse was suspected: microhematuria and proteinuria were found at routine urinalysis, while MRE findings were similar to the ones at baseline. The second case was for a 49-year old male previously treated with methotrexate for mild seronegative arthritis, reporting hematochezia and worsening of arthralgias. Inflammatory bowel disease (IBD) was suspected and colonoscopy revealed diffuse mucosal hyperemia. Computerized tomography of the terminal ileum appeared thickened and edematous, while skin biopsy showed leukocytoclastic vasculitis with IgA infiltrate. The patient was successfully treated with oral prednisone and, after two months from discharge, MRE was negative. Conclusion: IgAV may occur in adults and presenting with GI involvement may be particularly severe, mimicking IBD. MRE is a promising tool in diagnosing and monitoring IgAV.