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Last reviewed: 16 Mar 2025
Last updated: 08 Apr 2025

Summary

Definition

History and exam

Key diagnostic factors

  • rash
  • arthralgias
  • abdominal pain
  • signs of renal disease

Other diagnostic factors

  • drug history
  • scrotal pain or swelling
  • headaches
  • seizures
  • pulmonary hemorrhage

Risk factors

  • genetics
  • allergy
  • male sex
  • age 2 to 10 years
  • increasing age at onset
  • winter season/prior infection
  • medication

Diagnostic tests

1st tests to order

  • blood pressure
  • urinalysis
  • serum creatinine and electrolyte levels

Tests to consider

  • serum IgA levels
  • CBC and coagulation studies
  • skin biopsy
  • renal biopsy
  • ultrasound, abdomen
  • ultrasound, testicles

Treatment algorithm

Contributors

Authors

Louise Oni, MBChB, MRCPCH, MA, PhD

Senior Lecturer in Paediatric Nephrology and Honorary Consultant Paediatric Nephrologist

University of Liverpool

Department of Paediatric Nephrology

Alder Hey Children's NHS Foundation Trust Hospital

Liverpool

UK

Disclosures

In the past 12 months LO has contributed to expert advisory roles for Boehringer Ingelheim and Biocryst pharmaceuticals. LO has received a travel grant from Sandoz. These are unrelated to this article and all monetary payments are placed into an institutional educational charity account. LO is an author of references cited in this topic.

Peer reviewers

David Kershaw, MD

Professor of Pediatrics

University of Michigan

Ann Arbor

MI

Disclosures

DK is co-medical director for the board of directors of Nephcure.

Rajan Madhok, MD, FCRP

Consultant Physician and Rheumatologist

Centre for Rheumatic Diseases

Glasgow Royal Infirmary

Glasgow

UK

Disclosures

RM declares that he has no competing interests.

Richard A. Watts, MA, DM, FRCP

Consultant Rheumatologist

Ipswich Hospital NHS Trust

Ipswich

UK

Disclosures

RAW declares that he has no competing interests.

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