Henoch Schonlein Purpura

Henoch Schonlein Purpura is an IgA mediated vasculitis and it is the most common vasculitis seen in paediatrics.

The aetiology is unknown but it often follows on from an upper respiratory tract / non specific viral infection.

The peak age of onset is 4-6 years old.

Incidence is 10-20 per 100,000 children per year in the UK.

Pathophysiology

Group A strep, Epstein-Barr virus, Coxsackievirus, mycoplasma, hepatitis A and B, parvovirus B19, campylobacter and adenoviruses, and vaccines, have all been previously reported as triggers for HSP.

IgA immune complexes are deposited in small blood vessels in the skin, joints, kidneys, and gastrointestinal tract which causes inflammation.

Presentation

Presents as palpable purpura with any of the following:

Systems Involved

Skin

Symmetrical palpable purpuric rash on extensor surfaces of lower limbs and in pressure dependent areas.

The rash usually starts out as red spots or raised lumps and very quickly this progresses to palpable purpura over the lower legs, buttocks and knees. Can also occur on upper limbs but this is more rare. Occasionally blisters / ulcers can develop. (T, 2023)

HSP 1

A typical HSP rash to the lower limbs

HSP 2

Bilateral lower limb purpura seen in HSP with ankle swelling present

HSP 3

An image demonstrating how the rash can appear slightly lighter with smaller purpura

HSP4

A purpuric rash in HSP seen on darker skin

HSP 5

Purpric lower limb rash in HSP seen on darker skin

Gastrointestinal Tract

GI manifestations of HSP occur due to submucosal haemorrhages and capillary haemorrhage which causes fluid accumulation in the bowel wall. The small bowel is most affected.

GI involvement causes the following symptoms: abdominal pain (85%), vomiting (40%), GI bleeding (66%), massive lower GI bleed (20%) and diarrhoea (20%). Occasionally abdominal pain can be the presenting symptoms of HSP. (Khader Y, 2021)

Occasionally children with HSP can present with intussusception (3-4%) as the vasculitis acts as a lead point for the bowel invagination.

Joints

The incidence of joint involvement in HSP is up to 78% and 15% of children with HSP present with joint pain / swelling as the initial symptom.

Joint involvement includes arthritis and arthralgia and most of those with joint involvement have swelling. Pain can be migratory and recurrent. Joints involved can be unilateral or bilateral and are commonly the knees, ankles, hands and feet. (Wang X, 2016)

Kidneys

Around 30-50% of patients have evidence of renal involvement with HSP.  1-2% of these children progress to end stage renal failure.

Renal involvement can present as proteinuria, and/or microscopic or macroscopic haematuria, with more severely affected children presenting with nephritis and hypertension.

All other organ involvement in HSP is usually self-limiting and mild but HSP nephritis can evolve into end stage renal disease requiring dialysis and renal transplant

Several studies have demonstrated that a risk factor for renal involvement in HSP is increased age at diagnosis. (Kim WK, 2021)

Urogenital tract

It is rare to find scrotal involvement in HSP but cases do occur, presenting as acute testicular pain (mimicking testicular torsion), epididymitis and orchitis. Symptoms include scrotal pain and tenderness, erythema and swelling. (Dalpiaz A, 2015)

Differentials:

  • Connective tissues disease, e.g. Systemic Lupus Erythematosus (rashes, joint pains and swelling, renal involvement)
  • Idiopathic Thrombocytopaenic Purpura (Isolated low platelets following a viral infection, usually presents with nose bleeds and a non-blanching rash)
  • Meningococcal sepsis (presents with fever, widespread non-blanching purpura, these children deteriorate very quickly with sepsis)
  • Inflammatory Bowel Disease (presents with abdominal pain, bloody diarrhoea, also these children are prone to juvenile arthritis and eye involvement including uveitis)

Investigations:

HSP is a clinical diagnosis but there are a list of investigations that should be performed to rule out certain differentials and to look for complications. These include:

  • Blood pressure
  • Urine dip to look for proteinuria / haematuria
  • Bloods for FBC, U&Es, coagulation, LFTs and bone profile. Include a CRP if there is any history of fever in the context of a non blanching rash)
  • If there are signs of renal involvement such as haematuria or hypertension then further bloods should be done including an ASOT, DNAase B, complement 3 and 4.

Management

HSP is usually benign and self limiting and resolves without medical treatment within 6 weeks. Any intervention or treatment is usually supportive, e.g. analgesics

If there is joint pain / swelling ensure the child is taking regular paracetamol and (if renal function is normal and there is no evidence of GI haemorrhage) ibuprofen to control pain.

If there is severe abdominal pain, GI haemorrhage or acute painful testicular swelling ask for an urgent surgical review.

Children with any of the following should be discussed with the local paediatric renal team: acute nephritic syndrome, nephrotic syndrome, deranged U&Es, hypertension

Admission should be considered for: children unable to mobilise due to joint pain, children with severe abdominal pain not managed with simple analgesia, those with renal complications

Follow up

Most paediatric units in the UK have robust discharge plans in place for children with HSP to ensure adequate follow up. This usually involves referring to a community nursing team who monitor blood pressure and urine dip every 2 weeks for the first month and then monthly until 6 months

Secondary care follow up should be arranged for those who have persistent proteinuria, frank haematruia, hypertension, or derange renal function and low albumin.  

Bibliography

Dalpiaz A, S. R. (2015). Urological Manifestations of Henoch-Schonlein Purpura: A Review. Current Urology, 66-73.

Khader Y, B. C. (2021). Henoch-Schonlein Purpura Presenting as Upper Gastrointestinal Bleed in an Adult Patient. Cureus.

Kim WK, K. C. (2021). Risk Factors for Renal Involvement in Henoch-Schonlein Purpura. Jornal de Pediatria, 646-650.

T, G. (2023, June 20). Henoch-Schonlein Purpura. Retrieved from DermNet: https://dermnetnz.org/topics/henoch-schoenlein-purpura

Wang X, Z. Y. (2016). Henoch-Schonlein Purpura with Joint Involvement: Analysis of 71 Cases. Paediatric Rheumatology, 20.

Written and edited by Dr Rebecca Evans, Paediatric ST3

How useful was this post?

Click on a star to rate it!

Average rating 5 / 5. Vote count: 2

No votes so far! Be the first to rate this post.

As you found this post useful...

Follow us on social media!

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

Related Posts

Paediatrics_ Clerking & Discharge
Paediatrics: Clerking & Discharge tips
As an FY1 it is likely that you will manage paediatric patients...
Water
Paediatric IV Fluid Prescribing
Prescribing IV fluids in paediatrics is different to adult medicine...
Viral-exanthem-2
Common Viral Infections (exanthem) in Paediatrics
Viral infections are extremely common in paediatrics and a common...

Leave a Comment

Your email address will not be published. Required fields are marked *

Follow us

Favourites

Newsletter

Trending Now

Understanding the MSRA
The Multiple Specialty Recruitment Assessment (MSRA) is a computer-based exam increasingly being used...
Passing the Prescribing Safety Assessment (PSA)
The PSA is aimed at final year medical students and those graduating overseas to assess their competency...
Resident Doctor's Pay Calculator 2024
We’ve created a pay calculator to help you better understand your salary, how much tax you’ll...
Paracetamol Overdose
Paracetamol overdose is a common presentation in A&E and so you may often find yourself looking after...
Common Viral Infections (exanthem) in Paediatrics
Viral infections are extremely common in paediatrics and a common presentation to paediatric A&E is...
Prescribing IV Fluids
There are certain situations where you need to prescribe IV fluids which vary from fluid resuscitation...
PICC Lines and Midlines
You may well be asked to take blood from a PICC line or be called to see a patient because their PICC...

Sign up for our awesome resources & exclusive discount codes!

Join 80,000+ users who have signed up for our free weekly webinars, referral cheat sheet, pay calculator & exclusive discount codes for Pastest, Quesmed, Medibuddy and many others!