Definition

IgA vasculitis is a disease that involves purple spots on the skin, joint pain, gastrointestinal problems, and glomerulonephritis (a type of kidney disorder). It is also known as Henoch-Schönlein purpura (HSP).

Alternative Names

Immunoglobulin A vasculitis; Leukocytoclastic vasculitis; Henoch-Schönlein purpura; HSP; IgA vasculitis - Henoch-Schönlein purpura

Causes

IgA vasculitis is caused by an abnormal response of the immune system. The result is inflammation in the microscopic blood vessels in the skin. Blood vessels in the joints, kidneys, or the intestines may also be affected. It is unclear why this occurs.

The syndrome is mostly seen in children between ages 3 and 15 years, but it may be seen in adults. It is more common in boys than in girls. Many people who develop this disease had an upper respiratory infection in the weeks before.

Symptoms

Symptoms and features of IgA vasculitis may include:

• Purple spots on the skin (purpura). This occurs in nearly all children with the condition. This most often occurs over the buttocks, lower legs, and elbows.
• Abdominal pain.
• Joint pain.
• Abnormal urine (may have no symptoms).
• Diarrhea, sometimes bloody.
• Hives or angioedema.
• Nausea and vomiting.
• Swelling and pain in the scrotum of boys.
• Headache.

Exams and Tests

The health care provider will look at your body and look at your skin. The physical exam will show skin sores (purpura, lesions) and joint tenderness.

Tests may include:

• Urinalysis should be done in all cases.
• Complete blood count. The platelet should be normal.
• Coagulation tests: these should be normal.
• Skin biopsy, especially in adults.
• Blood tests to look for other causes of blood vessel inflammation, such as systemic lupus erythematosus, ANCA-associated vasculitis or hepatitis.
• In adults, a kidney biopsy should be done.
• Imaging tests of the abdomen if pain is present.

Treatment

There is no specific treatment. Most cases go away on their own. Joint pain may improve with NSAIDs such as naproxen. If symptoms do not go away, you may be prescribed a corticosteroid medicine such as prednisone.

Outlook (Prognosis)

The disease most often gets better on its own. Two thirds of children with IgA vasculitis have only one episode. One third of children have more episodes. People should have close medical follow-up for 6 months after episodes to look for signs of kidney disease. Adults have a greater risk of developing chronic kidney disease.

Possible Complications

Complications may include:

• Bleeding inside the body
• Blocking of the intestine (in children)
  
• Kidney problems (in rare cases)

When to Contact a Medical Professional

Contact your provider if:

• You develop symptoms of IgA vasculitis, and they last for more than a few days.
• You have colored urine or low urine output after an episode.

References

Calonje E, Brenn T, Lazar AJ, Billings SD. Vascular diseases. In: Patterson JW, ed. Weedon's Skin Pathology. 5th ed. Philadelphia, PA: Elsevier; 2021:chap 16.

Chadban SJ, Wyld M. Recurrent disease in kidney transplantation. In: Johnson RJ, Floege J, Tonelli M, eds. Comprehensive Clinical Nephrology. 7th ed. Philadelphia, PA: Elsevier; 2024:chap 113.

Dinulos JGH. Hypersensitivity syndromes and vasculitis. In: Habif TP, Dinulos JGH, Chapman MS, Zug KA, eds.  Skin Disease: Diagnosis and Treatment. 4th ed. Philadelphia, PA: Elsevier; 2018:chap 11.

Hahn D, Hodson EM, Willis NS, Craig JC. Interventions for preventing and treating kidney disease in Henoch-Schonlein purpura (HSP). Cochrane Database Syst Rev. 2015;(8):CD005128. PMID: 26258874 pubmed.ncbi.nlm.nih.gov/26258874/.

Kidd J, Weimer ET, Jennette JC. Vasculitis. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 54.

Shappell E, Miloslavsky EM. Systemic lupus erythematosus and the vasculitides. In: Walls RM, ed. Rosen's Emergency Medicine: Concepts and Clinical Practice. 10th ed. Philadelphia, PA: Elsevier; 2023:chap 108.

Sunderkötter CH, Zelger B, Chen KR, et al. Nomenclature of cutaneous vasculitis: Dermatologic addendum to the 2012 revised International Chapel Hill Consensus Conference Nomenclature of Vasculitides. Arthritis Rheumatol. 2018;70(2):171-184. PMID: 29136340 pubmed.ncbi.nlm.nih.gov/29136340/.