When Pediatrics Meets Internal Medicine: A Case of Adult-onset Iga Vasculitis Complicated by Acute Pancreatitis

Introduction: IgA vasculitis is a systemic small-vessel vasculitis characterized by the deposition of IgA-C3 complexes. Most cases occur in children. Clinical manifestations include palpable purpura, arthralgia, various gastrointestinal manifestations, and glomerulonephritis. Acute pancreatitis (AP) is a rare, life-threatening complication of IgA vasculitis with an incidence ranging from 0.4-0.5% in both adult and pediatric patients. We present a unique case of acute pancreatitis as a complication of adult-onset IgA vasculitis and compare clinical features in children and adults to promote early recognition and treatment.

Case Description: A 47-year-old male who underwent a right-sided total hip arthroplasty (THA) two weeks prior presented to the emergency room with one week of arthralgias, watery diarrhea, sharp epigastric pain, fever, and a rash on all four extremities. His initial symptom was diffuse joint pain. He progressively developed watery, non-bloody diarrhea and a non-pruritic, painless rash on in hands and feet. One day prior to presentation he developed a fever, sharp epigastric pain, nausea, and vomiting. He denied medication changes, confusion, dyspnea, recent travel, tick exposures, and sexual activity.

On initial presentation he was febrile, tachycardic and exhibited swelling of his bilateral hips and knees, severe epigastric tenderness to palpation, and a palpable, purpuric rash involving his distal extremities. Lab work showed significantly elevated lipase, microscopic hematuria with proteinuria, and an elevated C-reactive protein. After ruling out infectious and autoimmune conditions, his symptoms of arthralgias, acute pancreatitis, hematuria, and palpable purpura were most consistent with IgA vasculitis which was confirmed by skin biopsy. He was treated successfully with steroids.

Discussion: We present a patient with adult-onset IgA vasculitis complicated by acute pancreatitis. While our patient exhibited symptoms typical for IgA vasculitis, the development of AP muddied the picture. As such, the patient underwent a costly workup to exclude gastrointestinal, infectious, and autoimmune etiologies. Quick recognition of IgA vasculitis associated AP could have prevented unnecessary testing.

Of all age groups, IgA associated AP occurs most commonly in adolescent females. It is characterized by epigastric or peri-umbilical abdominal pain, nausea, and vomiting. Symptom onset differs between children and adults: in children AP occurs 2-30 days after the development of the rash while adults generally develop AP 7-8 days after onset of rash. In contrast to adults, AP can be the presenting feature of IgA vasculitis in children.

Laboratory analysis reveals elevated lipase levels in adults but normal levels in children. Imaging is generally unremarkable and most cases of AP in are benign. Lastly, while not used for standard AP, treatment with steroids resolved symptoms in all cases.

Conclusion: Despite its infrequency, acute pancreatitis must be considered in a patient with IgA vasculitis and severe epigastric pain. Early identification can promote rapid treatment and prevention of unnecessary medical testing.