IgA vasculitis (Henoch-Schönlein purpura) in children: initial tests and renal monitoring

• Measure blood pressure and look for oedema.

Laboratory tests

• FBC with platelets (purpura with normal platelets)
• Serum creatinine with eGFR, paediatric formula (if dipstick abnormal or moderate to severe form)if needednon-French guidelineThe IPNA asks for GFR calculation in every affected child ^[1] and the American AAFP review for initial kidney tests ^[2]. The Australian guide from the Royal Children's Hospital Melbourne reserves blood tests for moderate to severe forms ^[3].
• Serum albumin (if dipstick abnormal or moderate to severe form)if needednon-French guidelineThe IPNA asks for serum albumin in every affected child ^[1], as does the American AAFP review ^[2]. The Australian guide from the Royal Children's Hospital Melbourne reserves blood tests for moderate to severe forms ^[3].

Urine tests (first morning urine)

• Urine dipstick (haematuria, proteinuria)
• Urine protein:creatinine ratio (spot sample) (if proteinuria on the dipstick)if needednon-French guidelineThe IPNA asks for proteinuria to be quantified in every affected child ^[1]. The Australian guide from the Royal Children's Hospital Melbourne asks for this ratio only if the dipstick shows proteinuria ^[3].
• PTif needednon-French guidelineThe American AAFP review (2020) includes a coagulation screen in the initial tests, to rule out a coagulopathy ^[2] (expert opinion). The Australian guide from the Royal Children's Hospital Melbourne (2026) lists it among the further tests guided by the manifestations or differential diagnoses ^[3]. The British guidelines (UK Kidney Association, 2022) provide at diagnosis only for urinalysis and blood pressure ^[4].
• aPTTif needednon-French guidelineThe American AAFP review (2020) includes a coagulation screen in the initial tests, to rule out a coagulopathy ^[2] (expert opinion). The Australian guide from the Royal Children's Hospital Melbourne (2026) lists it among the further tests guided by the manifestations or differential diagnoses ^[3]. The British guidelines (UK Kidney Association, 2022) provide at diagnosis only for urinalysis and blood pressure ^[4].

Every month for at least 6 months, even if the urine remains normal

• Blood pressure and look for oedema at every check.
• Urine dipstick on first morning urine
• Urine protein:creatinine ratio on first morning urine (if proteinuria on the dipstick)if needednon-French guidelineThe IPNA asks for the initial assessment, including quantification of proteinuria, to be repeated every month ^[1]. The British guidelines, KDIGO and the Melbourne guide speak of urinalysis or urine monitoring without asking for this ratio routinely ^[3,4,5].
• Serum creatinine with eGFRif needednon-French guidelineThe IPNA asks for the whole initial assessment to be repeated every month (blood pressure, oedema, serum albumin, GFR, urinalysis) ^[1]; KDIGO mentions only monthly urine monitoring ^[5]. Do at least if proteinuria, haematuria, hypertension or oedema appear.
• Serum albuminif needednon-French guidelineThe IPNA asks for the whole initial assessment to be repeated every month (blood pressure, oedema, serum albumin, GFR, urinalysis) ^[1]; KDIGO mentions only monthly urine monitoring ^[5]. Do at least if proteinuria, haematuria, hypertension or oedema appear.

Every month for 6 months

• Urine dipstick
• Urine protein:creatinine ratio (first morning urine)
• Serum creatinine with eGFR

Then every 3 months for 6 months, then every 6 months for at least 5 years

• Urine dipstick
• Urine protein:creatinine ratio (first morning urine)
• Serum creatinine with eGFR

Then: once a year, for life

• Urine dipstick and blood pressure (if moderate to severe kidney disease)if needednon-French guidelineThe IPNA considers lifelong annual assessment of urine and blood pressure prudent in moderate to severe forms of kidney disease ^[1].