Non-Blanching Rashes Flashcards
Pathophysiology of a non blanching rash
Bleeding under the skin
Petechiae
Small (< 3mm), non blanching, red spots on the skin caused by burst capillaries
Purpura
Larger (3 – 10mm) non-blanching, red-purple, macules or papules created by leaking of blood from vessels under the skin
Differentials for a non blanching rash
Meningococcal sepsis
Henoch-Schonlein purpura (HSP)
Acute leukaemias
Haemolytic uraemic syndrome (HUS)
Mechanical
Henoch-Schonlein purpura (HSP)
Develops in an otherwise well child over days
Haemolytic uraemic syndrome (HUS)
Associated with oliguria and signs of anaemia.
This often presents in a child with recent diarrhoea
Mechanical cause of petechiae
Strong coughing, vomiting or breath holding can produce petechiae in a “superior vena cava distribution”, above the neck and most prominently around the eyes.
Investigations for a non blanching rash
FBC
U+Es: High urea and creatinine - HUS or HSP with renal involvement.
CRP
ESR - indication of HSP or infection.
Coagulation screen, including PT, APTT, INR and fibrinogen can diagnose clotting abnormalities.
Blood culture
Meningococcal PCR
Lumbar puncture - meningitis or encephalitis.
Blood pressure
Urine dipstick
What can a FBC indicate in a non blanching rash
Anaemia - HUS or leukaemia.
Low WCC -neutropenic sepsis or leukaemia.
Low platelets- ITP or HUS.
Why is blood pressure taken in a non blanching rash
HTN can occur in HSP and HU
Hypotension can occur in septic shock
What can a urine dipstick suggest in non blanching rash
Proteinuria and haematuria can suggest HSP with renal involvement, or HUS.
Management of a non blanching rash
Require urgent referral and investigation
SEPSIS 6 if indicates
Definitive management will depend on the underlying cause
