[57] Henoch-Schonlein Purpura

Question 1

What is Henoch-Schonlein Puprura (HSP)?

Answer 1

A small vessel vasculitis with particular characteristics

Question 2

What are the characteristics of HSP?

Answer 2

• Skin rash on extensor surface
• Arthralgia
• Periarticular oedema
• Abdominal pain
• Glomerulonephritis

Question 3

What age range is HSP most common in?

Answer 3

3-10 years

Question 4

When does the incidence of HSP peak?

Answer 4

In winter months

Question 5

How does HSP begin?

Answer 5

Genetic predisposition and antigen exposure increases circulating IgA levels and disrupts IgG synthesis

Question 6

What happens to IgA and IgG in HSP?

Answer 6

They interact to form complexes that activate complement and are deposited in affected organs precipitating an inflammatory response with vasculitis

Question 7

What are the risk factors for HSP?

Answer 7

• Male
• White
• Asian

Question 8

What are the symptoms of HSP?

Answer 8

• Fever
• Rash
• Joint pain
• Colicky abdominal pain

Question 9

If there is GI involvement in HSP how can this present?

Answer 9

Haematemesis and melena

Question 10

Describe the rash in HSP

Answer 10

Initially urticarial then maculopapular, purpuric and palpable

Question 11

Where does the rash in HSP typically affect?

Answer 11

Buttocks and extensor surfaces

Question 12

What is normally spared by the HSP rash?

Answer 12

The trunk

Question 13

How many patients with HSP are affected by arthralgia?

Answer 13

2/3

Question 14

What joints are particularly affected by arthralgia in HSP?

Answer 14

Knees and ankles

Question 15

What is diagnosis based on?

Answer 15

Combination of symptoms with supportive tests

Question 16

Why can diagnosis be made on symptoms alone?

Answer 16

Very few conditions present in the same way

Question 17

What supportive tests can be used in diagnosing HSP?

Answer 17

• Bloods
• Urine dipstick
• Renal biopsy
• Skin biopsy
• Abdominal investigations

Question 18

What may be elevated in bloods in HSP?

Answer 18

• Creatinine
• Urea
• CRP

Question 19

What are the urine dipstick findings in HSP?

Answer 19

Microscopic or macroscopic haematuria or mild proteinuria in 80% of patients

Question 20

When may renal biopsy be indicated?

Answer 20

To establish diagnosis or assess severity of suspected kidney disease

Question 21

What are the main findings on renal biopsy?

Answer 21

Increased cells and Ig deposition in the mesangium

Question 22

Is skin biopsy necessary?

Answer 22

Only rarely

Question 23

What might skin biopsy show?

Answer 23

Leucocytoclastic vasculitis

Question 24

What may atypical HSP be confused for?

Answer 24

• Papular urticaria
• SLE
• Meningococcemia

Question 25

Does HSP usually require treatment?

Answer 25

No - most have a benign course that resolve in 6 weeks

Question 26

What medication may be needed whilst HSP resolves?

Answer 26

NSAIDs to treat arthritis

Question 27

What can be used to manage severe abdominal pain in HSP?

Answer 27

Steroids

Question 28

What should occur after HSP has resolved in children with persistent renal symptoms and that required treatment?

Answer 28

Long-term follow-up

Question 29

What is long-term follow-up to look for?

Answer 29

CKD and hypertension

Question 30

When may hypertension and CKD develop after HSP?

Answer 30

After several years

Question 31

What are the potential complications of HSP?

Answer 31

- Intussusception - Ileua - Protein-losing enteropathy - CNS invovlement - Progressive CKD

Question 32

What are the risk factors for developing CKD after HSP?

Answer 32

- Heavy proteinuria - Oedema - Hypertension - Deteriorating renal function