Henoch Schönlein Purpura / IgA vasculitis
Henoch-Schönlein Purpura (HSP) is one of the most common vasculitides in children. It is characterised by palpable purpura, arthritis or arthralgia, abdominal pain or gastrointestinal haemorrhage and glomerulonephritis.
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EULAR/PRINTO/PRES 2010 classification criteria for Henoch-Schönlein Purpura* |
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Criterion |
Definition |
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Palpable purpura (mandatory) |
Purpura (palpable, not from thrombocytopenia) or petechiae typical with lower limb predominance* |
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Plus at least one of the following: |
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Abdominal pain |
Diffuse, acute, colicky pain; gastrointestinal bleeding |
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Histopathology |
Leukocytoclastic vasculitis with predominant IgA deposits or proliferative glomerulonephritis with predominant IgA deposits |
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Arthritis or arthralgia |
Swollen joints, pain with limited range of motion or joint pain without swelling or limited range of motion |
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Renal involvement |
Proteinuria > 0.3 g/24 hour; spot urine albumin to creatinine ratio > 30 mmol/mg; or > 2+ on dipstick; and/or haematuria, RBC > 5 cells/HPF or RBC casts in the urinary sediment |
*For purpura with atypical distribution, an IgA deposit in biopsy is required. RBC = red blood cell,
Cutaneous involvement: Most children recover completely within 4 weeks, but recurrences can occur. The rash is most prominent on dependent area, especially lower extremities, and buttocks. It may occur in other areas depends on physical activities. There are varieties of the rash from small petechiae to large ecchymoses, rare haemorrhagic bullae. Subcutaneous oedema over the hands and feet, around eyes and scrotum may occur.
Gastrointestinal involvement: It usually occurs within a week after the rash, but some patients can present with abdominal pain before other manifestations, which make it difficult to diagnose. Patients can present with gastrointestinal haemorrhage due to vasculitis in the bowel wall. If patients present with severe abdominal pain or do not respond to corticosteroid treatment, intussusception should be suspected.
Renal involvement: Glomerulonephritis affects around one third of the children and can progress to renal failure. It usually develops within 4-6 weeks after the rash. Glomerulonephritis occurs around 97% within 6 months, therefore physicians should follow up HSP patients and send for urinalysis for at least 6 months.
Joint involvement: Arthritis and arthralgias occur in 50-80% of children with HSP. Around 15-25% of patients, joint involvement can be the presenting symptom. HSP arthritis is predominantly a large joint arthritis involving knees, ankles, however other joints such as wrists, elbows and small joints of fingers can also be involved. Affected joints have painful ranges of movement due to periarticular swelling but the characteristic findings of warmth, erythema and effusion are often absent. Joint disease in HSP is transient and resolves within a few days to weeks without any residual damage. Articular features may reappear for a few weeks and subside.
Investigations: There are no specific laboratory tests to confirm for the diagnosis. Urinalysis and renal function tests are required to diagnose and monitor nephritis. Imaging e.g., Ultrasound, radiography, CT abdomen may be performed in complicated cases.
Treatment: Most HSP patients recover spontaneously. Short courses of NSAIDs (e.g., ibuprofen, naproxen) may be used in joint pain. Corticosteroids are indicated in the following:
- Severe abdominal pain/gastrointestinal haemorrhage
- Persistent nephrotic syndrome
- Crescents in more than 50% of glomeruli
- Severe scrotal oedema
- Rare severe manifestations e.g., CNS vasculitis, pulmonary haemorrhage
Immunosuppressive medications, including cyclophosphamide, cyclosporin, azathioprine, or mycophenolate mofetil, have been used to treat glomerulonephritis.
