This is a UKMLA-centred history guide for non-blanching rash in children.
Introduction
Non-blanching rashes in children can be a cause of worry and panic! This is understandable, as this can be a sign of a serious underlying condition. It is often associated with meningococcal sepsis, however, there are other causes which are more common and less concerning.
Having a structured approach to the history of a child presenting with a non-blanching rash will help ensure you cover all the important information, are able to work through the differentials, and initiate a safe management plan for the patient.
What do we mean by a non-blanching rash? ‘Non-blanching’ means that the rash does not disappear when pressure is applied. You may be familiar with the glass test, a common household test where the rash does not disappear when viewed through glass against the skin.
Non-blanching rashes are most commonly petechiae (<2mm) or purpura (>2mm). These are caused by bleeding under the skin. The rash may be widespread or localised to a particular area.
Presenting Complaint
You can still use the SOCRATES acronym to guide your gathering of information when assessing a rash:
Site
- Where is the rash?
- Which areas of the body does it affect?
A rash caused by Henoch-Schonlein Purpura (HSP) for example usually covers legs and buttock areas.
A more widespread rash may be seen in viral exanthem, or may indicate a more serious condition such as meningococcal sepsis, especially if rapidly spreading – this can be due to extensive thrombocytopenia.
A circumferential rash may raise suspicion of non-accidental injury (NAI) if it features strap marks or grab marks around wrists or neck area, which are unusual areas for accidental trauma. These may appear as linear bruises or abrasions. Bruises in non-bony areas such as face, ears and neck should always raise suspicion of non-accidental injury.
Onset
- When did the rash start?
- Did it start suddenly or did it gradually start appearing?
Some rashes which have sudden onset include meningococcal sepsis, which is often associated with fever and neck stiffness. Immune Thrombocytopenia (ITP) and HSP often present with sudden rashes which spread too.
Non-blanching rashes which present with more gradual and insidious onset include those associated with acute leukaemia and Haemolytic Uraemic Syndrome (HUS).
Character
- What does the rash look like?
- Petechiae vs purpura? (petechiae <2mm or purpura >2mm)
- How does it feel?
Palpable purpura is often associated with vasculitis, particularly HSP but can also be a feature of meningococcal sepsis.
ITP is typically non-palpable.
Radiation
- Is the rash spreading anywhere else?
A rapidly evolving or spreading rash could be consistent with meningococcal sepsis and viral exanthem.
Associated symptoms
- Any ulceration of the lesions?
- Any bleeding?
- Itch?
- Any respiratory symptoms?
- Had any recent cough/cold symptoms?
- Fever?
- Lethargy?
- Weight loss?
- N&V?
- Diarrhoea?
- Meningism – neck stiffness or photophobia?
It is important to ask about these symptoms, as preceding viral illness is often associated with HSP and ITP, which can help you narrow down your differentials.
A presentation with abdominal pain with diarrhoea and vomiting makes a diagnosis of HUS more likely.
If the rash is bleeding and itchy, this may suggest a type of allergic reaction where the child has caused trauma to the area by scratching.
Fever, lethargy, weight loss and other systemic symptoms can suggest a serious underlying cause such as acute leukaemia, which is an important differential to consider if the child has presented with a non-blanching rash and chronic signs and symptoms.
Neck stiffness, fever and rash raises suspicion for meningitis or meningococcal sepsis, and should raise alarm bells in your head that this child is acutely unwell and should be discussed urgently with a senior.
Timing
- Has the rash changed since you first noticed it?
- Is it rapidly spreading?
A rapidly spreading non-blanching rash should raise suspicion of meningococcal sepsis. The bacterial pathogen which typically causes this, Neisseria meningitidis, releases toxins in the bloodstream which damages the blood vessels, leading to the appearance of a rash as blood leaks into the skin.
Exacerbating and relieving factors
- Have you tried anything that has helped the rash/made it worse?
Rashes caused by an allergic reaction may improve with antihistamine treatment and using topical treatments
The use of NSAIDs usually make rashes in HSP, ITP and HUS worse and increase risk of bruising and bleeding.
A non-blanching rash in meningococcal sepsis should clinically improve with prompt treatment including IV antibiotics and supportive care e.g. hydration.
Severity
May not be very relevant to rash history unless the patient is experiencing any pain with the rash.
Red Flags
It is important to demonstrate to the examiner that you are aware of some of the serious causes of a non-blanching rash and ask about red flag features to screen for them.
Symptoms that suggest meningococcal sepsis include fever, neck stiffness, photophobia, lethargy, and headaches. The child will look unwell and likely be scoring on the PEWS chart, and have abnormal signs such as increased HR, temperature, irritability in infants and even reduced conscious level.
Acute Lymphoblastic Leukaemia (ALL) is another serious cause of a non-blanching rash. This is a type of blood cancer and is the most common cancer seen in children. ALL results in low platelets (thrombocytopaenia) and low red blood cells (anaemia), so the child will often present with a history of breathlessness or fatigue, pale complexion, easy bruising, in addition to fever or history of recurrent infections. The symptoms can often be vague and so it is important to keep this differential in mind.
Make sure to keep safeguarding and non-accidental injury in the back of your mind as a potential differential with this presentation. Features that could suggest NAI or raise concerns about safeguarding include delayed presentation to GP/hospital, an inconsistent history from parents and carers about when the rash started, and changes in the child’s or parents’ behaviour.
Other features which should raise concerns include bruising in areas not commonly injured in accidental trauma, such as behind the ears, back, thighs, and upper arms. Remember that non-ambulant children are unlikely to have bruises.
If you have any concerns about the child’s wellbeing or safeguarding concerns, you should communicate this to a senior and discuss with your paediatric safeguarding lead, who will be able to advise on how to manage the situation appropriately.
You should specifically ask about these red flag signs and symptoms, to cover serious causes of non-blanching rashes:
- Spreading rash/petechiae or purpura
- Persistent fever
- Child appears lethargic, pale, floppy i.e. septic child
- Prolonged CRT >2sec
- Hypotensive (usually a late sign of shock in children)
- Easy bruising
- Bulging fontanelle in neonate
- Any symptoms of meningitis (including photophobia, neck stiffness, headache)
- Any change in consciousness/ reduced GCS (may present with irritability, uncontrollable crying, confusion, aggressive behaviour in a child, this is why it is always helpful to ask the parents/carers if this behaviour is normal for the child)
Differentials
Background
In any paediatric history you will ask about past medical history including birth history (prenatal, perinatal and postnatal), medications and immunisation status, allergies, social and developmental history, and family history. Here are some extra things to ask about which demonstrate your knowledge about the causes of non-blanching rashes in children:
Past Medical History – ever had a rash like this before? Any preceding viral illness/ diarrhoea (as we discussed above often associated with ITP and HSP, also to note HUS usually preceded by gastroenteritis)
Family History – any FH of any clotting disorders? Most common hereditary bleeding disorders include haemophilia A, haemophilia B, and von Willebrand disease.
While coagulopathy is a very rare cause of a non-blanching rash in a child, it is important to show you have considered this and can rule it out as a differential.
Examination
When examining the patient, you should keep your differentials in mind and look for signs that confirm or refute your potential diagnosis. Children presenting with a non-blanching rash will usually have blood tests including an FBC, blood film and CRP with further investigations as indicated by their presenting features.
Author – Dr Charlotte Wilson
Editor – Dr James Mackintosh
Last updated 22/01/2026
