henoch-schonlein purpura Flashcards
define HSP
IgA vasculitis, clinical diagnosis
features include rash and one or more of:
- arthritis/arthralgia
- abdominal pain
- nephritis
pathophys of HSP
immune mediated small vessel IgA vasculitis
IgA and compliment C3 are depositied into the vessel walls leading to inflammation
mechanism underlying is unknown, thought to be triggered by abnormal immune response following upper respiratory tract infection
epidemiology of HSP
most common cause of non-thrombocytopaenic purpura
incidence peaks 4-6 years old
M>F
URTI may occur 7-14 days before symptoms
seasonal peak in winter
Hx of HSP
clinical manifestations vary in order of appearance
pupura occurs in all cases but is the presenting complaint in only 75% of cases
recent URTI is present in 50% of cases, commonly viral or GAS infections
abdominal pain associated with nausea and vomiting
general observations
hypertension (suggests renal involvement)
low grade fever may be present
skin Ex
palpable purpura, peteciae and eccymosis
may be preceded by urticarial, erythematous, maculopapular os bullous skin lesions, usually cymmetrical on gravity/presssure depednant areas (eg. buttocks and lower limbs)
panful non pitting subcutaneous oedema (commonly periorbital or depednant areas (hands, feet, scrotum)
joints Ex
transient arthralgia +- arthritis
usually affects large joints of the lower limbs, rarely upper limbs
usually no effusion or warmth
may cause difficulty weight bearing
abdominal Ex
diffuse abdominal pain intermittant and colicky
generalised tenderness
diarrhoea with occult blood
signs of bowel obstruction/pritonism
most common complication is intussusception
genital Ex
testcular pain, orchitis, necrosis, cord hematoma
exclude testicualr torsion
urinalysis
haematuria (microscopic or macroscopic)
protienuria (mild to severe)
investigation
urinalysis is usually the only one needed in classic presentation
urine MC, urinary protein creatinine ratio and UEC and albumin may also be necessary if there is hypertension, macroscopic haematuria or significant proteinuria
FBC to rule out ITP?
investigation for severe abdo pain
abdominal US to exclude intussusseption
treatment flow
follow up
critical to ientfy subsequent renal involvement which rarely requires renal biopsy +- immunosuppression
treatment for mild pain
subcutaneous odema is managed with bed rest and elevation of the affected area
paracetamol and NSAIDs
treatment for moderate/severe pain
consider steroids (prednisolone) for moderate/severe joint pain or abdominal pain
may reduce duration of symptoms, do not impact rate of long term renal complications
prognosis
usually resolves within 4 weeks, rash is usually last symptom to remit
joint pain usually resolves within 72 hours
uncomplicated abdominal pain usually resolves within 24-48 hours
HSP may recur within 4 months of the intiial presentation, subseuent episodes are usually associated with milder symptoms of shorter duration that the previous episodes
how do you know if its meningoccocal disease
child will be systemically unwell with a high grade fever
may also be signs of shock (hypotension and tachycardia)
child is usually stable in HSP
how do you know if its actually ITP
fall in platelet count
how do you know if its actually haemolytic uraemic syndrome
triad of thrombocytopaenia, AKI, and microangiopaathic haemolytic anaemia
caused by E coli infection
also presents with abdo pain and petechial rash, key distinguishing feature is bloody diarrhoea
progression to renal failure
1% of HSP
more likley in patients that present withh nephrotic or nephritic syndrome
