Question 1: For children diagnosed with Henoch-Schönlein purpura (HSP), what percentage develop abdominal pain prior to developing the typical purpuric rash?
HSP, recently renamed immunoglobulin A (IgA) vasculitis, is a small vessel vasculitis that most commonly affects the skin, joints, bowel, and kidneys. In general, the location of the vasculitis reflects the most common symptoms: skin (purpuric rash), joints (arthralgias), bowels (abdominal pain with possible bloody stools and may serve as a lead point for intussusception), and kidneys (hematuria). Nearly every patient gets the purpuric rash with some combination of the other symptoms. It’s much more common in children but does occur in adults as well.1 Children typically present with the purpuric rash but not always.
Saulsbury retrospectively found that 63 out of 100 HSP patients had abdominal pain during the course of the disease, and 33 out of 100 had gastrointestinal (GI) bleeding.2 Of these 100 children, 19 had abdominal pain as the initial presenting symptom prior to the rash. Fourteen patients developed rash within one week of abdominal pain, but five of the patients had abdominal pain for nine to 14 days before they developed the purpuric rash. Chao et al found that GI symptoms (abdominal pain, GI bleeding, vomiting, etc.) preceded the rash in 17 out of 158 of patients (11 percent).3 Pain was the predominant GI symptom. Other retrospective studies by Trapani et al and Chen et al had similar findings of 11 percent (17 out of 150) and 12 percent (14 out of 120), respectively.4,5 A recent study by Gupta et al found abdominal pain preceding the purpuric rash in 36.8 percent of HSP cases.1
At the end of the day, having abdominal pain alone, without the typical purpuric rash, is probably more common than we may think. It’s important to keep HSP (IgA vasculitis) in the differential diagnosis of patients with abdominal pain and make certain to perform a thorough skin assessment.
In HSP, abdominal pain presenting prior to the typical purpuric rash ranges from 11 to 36 percent in pediatric cases, according to a number of retrospective studies.
Dr. Jones is assistant professor of pediatric emergency medicine at the University of Kentucky in Lexington.
Dr. Cantor is professor of emergency medicine and pediatrics, director of the pediatric emergency department, and medical director of the Central New York Regional Poison Control Center at Upstate Medical University in Syracuse, New York.