Immunoglobulin A Vasculitis

Overview


Plain-Language Overview

Immunoglobulin A Vasculitis is a condition that causes inflammation in the small blood vessels, primarily affecting the skin, joints, intestines, and kidneys. It mainly involves the immune system producing excess IgA antibodies that deposit in blood vessel walls, leading to swelling and damage. This inflammation can cause a distinctive rash of purplish spots, joint pain, abdominal pain, and sometimes kidney problems. The condition is most common in children but can affect adults as well. It often follows an infection, such as a cold or throat infection. The main health impact comes from the blood vessel inflammation causing symptoms and potential organ involvement.

Clinical Definition

Immunoglobulin A Vasculitis (formerly Henoch-Schönlein purpura) is a systemic small-vessel vasculitis characterized by IgA1-dominant immune complex deposition in vessel walls. It is typically triggered by an abnormal immune response to infections, leading to leukocytoclastic vasculitis with palpable purpura, arthralgia, abdominal pain, and renal involvement. The pathogenesis involves IgA immune complex deposition in postcapillary venules, causing complement activation and vessel inflammation. It is the most common vasculitis in children and can cause significant morbidity due to glomerulonephritis. Diagnosis relies on clinical presentation and histopathology showing IgA deposition on immunofluorescence. The disease is usually self-limited but requires monitoring for renal complications.

Clinical Presentation


Diagnostic Workup


Pathophysiology


Treatments


Prevention


Outcome & Complications


Differential Diagnoses


Medical Disclaimer: The content on this site is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. If you think you may be experiencing a medical emergency, call 911 or your local emergency number immediately. Always consult a licensed healthcare professional with questions about a medical condition.

Artificial Intelligence Use: Portions of this site’s content were generated or assisted by AI and reviewed by Erik Romano, MD; however, errors or omissions may occur.

Analytics Disclosure: If you allow analytics cookies, Doctogenic uses Google Analytics, Microsoft Application Insights, and Microsoft Clarity to understand site usage, diagnose issues, review heatmaps and session replay recordings, and improve the service on pages where those tools are enabled. Clarity is not enabled on account, purchase, billing, checkout, Stripe-related, or admin pages. You can change this choice through Cookie preferences.

USMLE® is a registered trademark of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). Doctogenic and Roscoe & Romano are not affiliated with, sponsored by, or endorsed by the USMLE, FSMB, or NBME. Neither FSMB nor NBME has reviewed or approved this content. "USMLE Step 1" and "USMLE Step 2 CK" are used only to identify the relevant examinations.