Makindo Medical Notes.com

In adults the renal disease is more insidious and myocardial involvement may occur

About

• HSP is a systemic small vessel leukocytoclastic vasculitis
• Raised Palpable purpuric rash (bleeding into dermis) over buttocks
• Affects skin, joints, kidneys and GI tract

Aetiology

• IgA deposition within small blood vessels with immune complex deposition in smaller venules, capillaries and arterioles
• Often associated with infectious agents such as group A Streptococci and Mycoplasma

Clinical

• The rash spares the trunk and face usually over lower limbs and buttocks.
• Commonest cause of vasculitis in children but can be seen in all ages
• Abdominal pain and even PR bleeding and intussusception

Investigations

• FBC, U&E and clotting if non-classical purpura or systemic unwell or evidence of renal involvement
• Urinalysis for Haematuria and Proteinuria 2+ is significant
• Throat swab and ASOT

renal disease found

• Complement C3 and C4 levels are normal [Low in Post strep GN]
• Skin biopsy with immunofluorescence: leukocytoclastic vasculitis with IgA and C3 deposition
• Renal biopsy typically shows a focal segmental proliferative GN with mesangial IgA deposition similar to IgA nephropathy

Management

• The prognosis is usually very good and most settle conservatively without treatment. Management is supportive.
• Children with mild and classical presentations only urinalysis may be needed with escalation if unwell, malaise and joint involvement or proteinuria and haematuria.
• Patients/parents can do daily urine dipsticks for several weeks to monitor renal involvement. If renal disease then needs escalation.
• Rarely lead to rapidly progressive Glomerulonephritis and steroids or immunosuppression may be indicated. About 1-5 % end up with End stage renal failure