The features of Henoch Schonlein Purpura, the most common vasculitis affecting children can be recalled by the ARENA mnemonic [A = abdominal pain (65% of cases), R = rash (100%), E = edema, N = nephritis (40%), A = arthritis (75%)].
The following, HSP and Intussusception, PUBLISHED JUNE 8, 2012 · UPDATED SEPTEMBER 22, 2012, is from Dr. Sean Fox’s outstanding Pediatric EM Morsels blog:
Intussusception and HSP
- Intussusception can be seen as a complication of HSP in 2-6% of cases.
- HSP associated intussusception generally occurs in children >2yrs of age.
- 70% occur in ileoileal locations, with only 30% being ileocolic (unlike typical intussusception, which occurs most commonly at ileocolic locations.
- Contrast enema may not diagnose it, because of the ileoileal location.
- Ultrasound is preferred imaging modality, augmented by serial examinations.
- Upper GI Series with small bowel follow-through may be necessary as well.
For more details on Henoch Schonlein Purpura see Henoch Schonlein Purpura – Help From Pediatric EM Morsels Posted on March 18, 2017 by Tom Wade MD
Whenever I am considering a pediatric patient with abdominal pain, I like to review my post Pediatric Acute Abdominal Pain Posted on July 13, 2016. The post is a quick but complete review of pediatric abdominal pain.
See also excellent Clinical Practice Guidelines: Henoch-schonlein purpura (November, 2016) from the Royal Children’s Hospital of Melbourne. This is, I think the best single resource for Henoch Schonlein Purpura. What follows are just excerpts from that resource (so definitely click on the source):
Key Points
- Urinalysis is the only investigation required in a classic presentation of HSP. Further investigations may be required if the diagnosis is unclear, abdominal symptoms are severe or where there is evidence of significant renal involvement (hypertension, macroscopic haematuria or proteinuria)
- Most cases are self-limiting and require only symptomatic management
- Close follow-up is critical to identify significant renal involvement requiring intervention. Such renal involvement can be asymptomatic
Investigations
- Urinalysis is usually the only investigation needed in a classic presentation of HSP
- If there is hypertension, macroscopic haematuria or significant proteinuria, send urine for formal microscopy and protein-creatinine ratio (UPCR), and bloods for urea/electrolytes/creatinine (UEC) and albumin
- In some instances further investigations are requested to (a) rule out differentials if the diagnosis is unclear, or (b) to identify potential complications of HSP. These may include
- FBE, UEC, albumin
- Blood and urine culture
- Abdominal imaging
- ANA, dsDNA, ANCA, C3/C4 if significant renal involvement with an unclear diagnosis
Consider consultation with local paediatric or surgical team
- Serious abdominal complications
- Significant renal involvement – see Follow-Up below
- Pulmonary involvement
- Neurological involvement
Indications for Admission
- Serious abdominal complications
- Severe debilitating pain
- Severe renal involvement (see ‘discussion with Nephrology’ under ‘Follow-Up’ below)
- Neurological involvement
Prognosis
- A first episode of HSP, in the absence of significant renal disease, usually resolves within 4 weeks. The rash is usually the last symptom to remit.
- Joint pain usually resolves spontaneously within 72 hours
- Uncomplicated abdominal pain usually resolves spontaneously within 24-48 hours
- In 25-35% of patients, HSP recurs at least once, usually within 4 months of the initial presentation. Subsequent episodes are usually milder and shorter in duration than previous episodes.
- 90% of those who develop renal complications do so within 2 months of the onset, and 97% within 6 months
Follow-Up
- Regular GP or paediatrician review is critical to identify subsequent renal involvement which rarely requires a renal biopsy +/- immunosuppression
- If the initial urinalysis is normal or only reveals microscopic haematuria, review clinically and check BP/early morning urinalysis at these recommended time intervals:
- Weekly for the first month after disease onset
- Fortnightly from weeks 5-12
- Single reviews at 6 and 12 months
- Return to 1. if there is a clinical disease flare
- The development of hypertension, proteinuria or macroscopic haematuria at any point should prompt paediatric review with investigations (outlined above) and ongoing follow-up based on results
- Discussion with a Renal specialist is recommended if there is:
- Hypertension
- Abnormal renal function
- Macroscopic haematuria for 5 days
- Nephrotic syndrome
- Acute nephritic syndrome
- Persistent proteinuria
- UPCR >250mg/mmol for 4 weeks
- UPCR >100mg/mmol for 3 months
- UPCR >50mg/mmol for 6 months
- If there is no significant renal involvement plus normal urinalysis at 12 months, no further follow-up is required
