Pathology:
Small vessel vasculitis characterised by deposition of immunoglobulin A (IgA) in both the skin and kidneys.
Aetiology:
Henoch-Schonlein purpura (HSP) is much more common in young males and often follows an upper respiratory tract infection (URTI).
Symptoms:
- Abdominal pain
- Haematuria
- Musculoskeletal pain
- Rash
Signs:
- Purpura on the legs and buttocks
- Arthralgia
- Abdominal pain
- Gastrointestinal (GI) haemorrhage (often due to intussusception)
- Haematuria
Investigations:
- Bloods: Raised IgA, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP); full blood count (FBC) shows a raised platelet count.
- Skin biopsy: IgA and complement 3 (C3) in the blood vessel wall.
Treatment:
- Conservative: Spontaneous recovery occurs within 4 weeks.
- Medical: Analgesia for arthralgia.
Complications:
Long-term complications are secondary to renal involvement and require follow-up for up to one year to monitor renal function and blood pressure.
Prognosis:
Excellent.
Figure 8.5 Henoch-Schonlein Purpura
