A case-based review of IgA vasculitis complicated with gastrointestinal infections: insights from a norovirus-associated case in an adolescent.

Immunoglobulin A vasculitis (IgAV), formerly known as Henoch-Schönlein purpura, is a self-limited leukocytoclastic vasculitis targeting small-sized vessels. It is the most common vasculitis in children, but also targets adults who have usually worse prognosis. It typically presents with purpuric rash, arthritis, colicky abdominal pain and potential renal involvement. Gastrointestinal (GI) manifestations, although frequent, may be severe and occasionally complicated by infections. We present a 11-year-old male with a recent diagnosis of IgAV who was admitted with severe abdominal pain, hematemesis and hematochezia. Stool analysis identified Norovirus as the causative pathogen for the severe gastrointestinal symptoms. Treatment with proton pump inhibitors, high-dose corticosteroids and intravenous fluids resulted in symptoms resolution and clinical improvement. In addition, a case-based review of the literature was conducted to evaluate the prevalence of GI infections occurring after the development of IgAV that may result in severe complications or disease relapses. Thirty-five patients with a median age of 14 years were included in our study. Among these patients, 42.9% were diagnosed with a concomitant bacterial gastrointestinal pathogen, followed by 25.7% with viral gastroenteritis and 17.1% with parasitic gastrointestinal disease. Treatment was individualized, with 48.5% receiving corticosteroids and 8.6% receiving immunosuppressive therapy. This case and case-based review highlights the significance of careful management and monitoring of patients with IgAV complicated by infections, because severe complications can cause significant morbidity and mortality especially in adults.