EM@3AM: Henoch-Schonlein Purpura (HSP)

Author: Brit Long, MD (@long_brit, EM Attending Physician, San Antonio, TX) // Edited by: Alex Koyfman, MD (@EMHighAK) 

Welcome to EM@3AM, an emDocs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

A 6-year-old male presents with rash, joint pain, and abdominal pain. VS are normal, and exam reveals palpable purpura in the lower extremities. His abdomen is not tender to palpation, and his testicles are normal. Platelets and coagulation panel are normal. The patient otherwise appears well, with no prior history, and vaccines are up to date.

What is the diagnosis, and what are your next steps?

Answer: Henoch-Schonlein purpura (HSP)

Background:

– HSP is an IgA vasculitis that commonly occurs in the pediatric population (peak incidence 4-6 years of age).

– The disease is more common in white and Asian males.

– Most cases are preceded by an infection (such as URI).

– Widespread IgA deposition in blood vessel walls causes leukocytoclastic vasculitis, which is the most common vasculitis in pediatric patients.

– It is typically self-limiting and resolves within 4 weeks.

– Conditions to consider include DIC, acute abdomen, testicular torsion, systemic vasculitis/rheumatologic disorder, ITP, TTP, HUS, endocarditis, meningococcemia.

Presentation:

– Symptoms usually develop over days to weeks and are variable. Think of “ARENA”.

Abdominal pain – Occurs in 65% of cases and is typically diffuse and colicky.  Vomiting and bloody stool may be present. Importantly, intussusception is rare but may be a complication in 2-6% of cases (70% are ileoileal, rather than the classic ileocolic).

Rash – Occurs in up to 100% of cases, with palpable purpura the classic form. This often starts as wheals that progress to ecchymoses, petechiae, and purpura which appear in symmetrically distributed crops in gravity/pressure-dependent areas. It is usually not pruritic. Thrombocytopenia should not be present.

Edema – This is marked by angioedema of the scalp, eyelids, back, feet, and groin.

Nephritis – Occurs in 40% of cases and is the feared complication of HSP. Patients may have gross hematuria, but nephritis may not develop for months after the diagnosis and may become chronic.

Arthritis/Arthralgias – Up to 75% of patients with HSP experience this, commonly in the knees and ankles. This can be very painful but is non-deforming and self-limited. Arthritis may precede the rash, which makes diagnosis of HSP difficult.

*Testicular pain may be present, and testicular/scrotal swelling typically occurs due to vasculitis and bleeding.

Diagnosis:

HSP is based on clinical manifestations, and laboratory markers are typically non-specific.

– Obtain CBC (normal platelets), chemistry, coagulation panel (normal), urinalysis, ESR/CRP (elevated), stool guaiac (>50% positive). Abdominal US should be considered if intussusception is a possibility. Concern for testicular torsion requires testicular US.

Management:

– Treatment is typically supportive. NSAIDs are often used for pain, but they can worsen renal and GI disease. Acetaminophen can be used as well.

– Steroids (prednisone 1mg/kg/day) should be considered for renal disease and severe abdominal pain, but they are currently controversial.

Disposition:

– Most patients can be treated in the outpatient setting with follow-up. Nephrology and Rheumatology consults for follow-up are also warranted.

– Patients with severe abdominal pain, severe vomiting, or severe renal disease may require admission.

– Recurrence rate reaches 33% and should be discussed with caregivers.

References/Further Reading:

Chen JY et al. Henoch-Schönlein purpura nephritis in children: incidence, pathogenesis and management. World J Pediatr. 2015 Feb;11(1):29-34.

Saulsbury, FT (1999) Henoch-Schönlein purpura in children. Report of 100 patients and review of the literature. Medicine (Baltimore) 78: pp. 395-409

Saulsbury FT. Henoch-Schonlein Purpura. Current Opinion in Rheummatology. Jan. 2001;13(1):35-40.

Little KJ, Danzl DF. Intussusception associated with Henoch-Schonlein Purpura. The Journal of Emergency Medicine: 1991;9(1):29-32.

Chamberlain RS, Greenberg LW. Scrotal involvement in Henoch-Schonlein Purpura: A case report and review of the literature. Pediatric Emergency Care;8(4):213-215.