Dr Sean O’Donnell, Dr Suzie Johnson, Dr Vikram Baicher, PEM Consultant, Ms Nia Fraser

Blood in stool is a relatively common presentation to A&E. Causes can range from the very minor to the catastrophic. Meanwhile, patients that appear quite well can have serious underlying pathologies.

In this article we’re going to take you through a fictional shift in A&E where all your patients have ‘Blood PR’ as their primary symptom.

In each case, we highlight some of the diagnostic and logistical challenges and we will try and share some of our practical experience with you so that you can feel more confident when you are next presented with this symptom. (Throughout the article we use pictures to illustrate what our experience of blood PR might look like with each pathology – this should not be taken as an endorsement of the websites themselves).

Let’s get to it…

Your first patient is Daniel…

Daniel is 15 months old. He has been brought to A&E by his mum Janice because that morning Daniel passed a stool with blood in it. Daniel doesn’t seem to be in any pain or discomfort and Janice was quite surprised to see blood in his nappy with what looked like normal stool. 

Image source

Daniel is normally fit and well. He has no allergies and takes no regular medications. He’s seen his GP a few times with coughs and colds but never been admitted to hospital.

Whilst waiting to be seen in A&E Daniel has opened his bowels again. This one is liquid dark red blood now not mixed with stool.

You examine Daniel.

He is sat in mum’s lap, happy and smiling.

A – No concerns

B – RR 20, Saturations 99% in room air. His chest is clear

C – HR 140, Blood pressure 104/79

D – Abdomen is soft. No masses or pain.

E – You see no rashes. He is moving his arms and legs normally.

You pause and consider the differentials.

You then ask mum and few more questions whilst considering the following:

  • Foreign body – there is no history of this. Specifically you consider button batteries.
  • Food colouring – Daniel hasn’t been raiding the baking cupboards and hasn’t eaten lots of beetroot
  • Colon polyp – There is no family history or previous bleeds but you are keeping an open mind.
  • Infective causes – No one else at home is unwell and Daniel has not eaten anything unusual or undercooked as far as mum can recall.
  • Intussusception – this is possible. However, Daniel hasn’t been in pain or distress.
  • Meckel’s – there is ongoing painless rectal bleeding.
  • Inflammation – Daniel’s age and length of history makes this very unlikely to be inflammatory bowel disease (IBD).
  • Cow’s Milk Allergy  – Your consultant has reviewed the blood in stool and thinks the volume is too much for this diagnosis
  • Fissure – You can’t see any external anal fissures and you know PR examinations in children should not be routinely done. If they are to be done then it should be by a surgeon.

On the balance of symptoms present you think a surgical cause is more likely and make a referral.

Your paediatric surgery colleagues accept the patient for transfer (or come to see them in your ED). You aid them by ensuring there is vascular access and bloods are sent – the Haemoglobin is 90 so you also send a Group & Save.

The surgical team are concerned about a Meckel’s diverticulum. They arrange an ultrasound which doesn’t show intussusception and they proceed to theatre the next day for a laparoscopy, this shows a Meckel’s so an open operation to resect this is performed, the bowel is re-joined and Daniel remained stable.

Daniel had some post-operative pain and was slow to feed and pass a stool, but his symptoms settled with analgesia and he recovered well. He was discharged Day 3 post-op with safety netting by the surgical team.

Top Tips – Meckel’s diverticulum

The Meckel’s ‘Rule of 2s’:
– Most present <2 years of age
– 2% of the population have one (some are asymptomatic life-long)
– The diverticulum is around 2 inches long and around 2 feet from the ileo-caecal valve
– 2 types of ectopic mucosa are often found inside (like gastric & pancreatic) causing a bleeding ulcer

Button battery or magnet ingestion is usually apparent from the history but is always worth considering. Have a low threshold for performing an X-Ray if there is any doubt.

Many types of hearing aids use button batteries – sometimes grandparents who aren’t used to caring for toddlers can leave batteries within reach.

Meckel’s Diverticulitis can be indistinguishable from appendicitis and some of these children are sometimes discovered to have a Meckel’s at their laparoscopic appendicectomy.

Case 2. Your next patient is Sally…

Sally is 13 months old and has been brought by her grandmother, Valerie, due to new intermittent tummy pain over the last 12 hours and a red nappy. Sally seems fine now but the pain described was really severe and lasted for 20 minutes, nothing would settle her down at that time. Shortly after the 3rd bout of this she passed a very runny brown stool followed by a clump of dark red. This has never happened before and she hasn’t stooled since. Her appetite remains normal when she isn’t in pain. Sally is normally fit and well. She has no regular medications and has no allergies.

Valerie is almost apologetic for bringing Sally to a busy emergency department because she now seems absolutely fine!

You ask if there are any pictures of the stool. Valerie has a picture…

Image source

You examine Sally:

A – No concerns

B – RR 22, SaO2 99%

C – HR 150, BP 108/68, well perfused, femoral pulses present bilaterally

D – Abdomen is soft. Sally’s bottom looks normal on external inspection.

E – No rash, no temperature, no limb or apparent neurological abnormality

You give analgesia and anti-emetic, then consider the differentials for Sally’s episodic pain and bleeding. You consider intussusception, but she looks too well! On the balance of things and the picture which Valerie has taken, you speak to your boss who advises a referral to the paediatric surgeons and whilst awaiting their review you site a cannula, take off routine bloods, commence some IV fluids and ask that Sally is kept nil by mouth (NBM).

The paediatric surgeons review Sally and arrange an ultrasound to look for intussusception. The USS showed a target sign (see picture below) and diagnosis of ileo-colic intussusception.

As Sally remains stable she goes to Paediatric radiology and has successful air enema reduction of the intussusception on the 2nd attempt, she’s observed overnight and remains well. She was discharged the next day with safety netting by the surgical team. Had Sally been in a centre that doesn’t have this capacity then a referral to the regional Paediatric Surgical centre would be advised.

Used with consent of parents. USS image shows an Ileocolic intussusception in the right upper quadrant/supra-umbilical region. Elsewhere there was no obvious free fluid. There were a few small reactive mesenteric lymph nodes. 

Some call this the Target sign, Doughnut sign or Bull’s eye sign. If USS is your thing, take a look at this Radiopaedia page for more examples. Target sign (intussusception)


Intussusception can have a varied presentation. From the very well looking to seriously ill. In particular it is worth considering this diagnosis in children 6 months – 2 years of age where there are episodic bouts of pain, leg drawing up or pale episodes. In the author’s experience there may or may not be blood in the stool. Some textbooks have documented jelly like stool as a late sign in intussusception but in the authors experience the presence of blood is not always jelly like and can occur early in the illness, so don’t rely on the presence or absence of this symptom.

In the authors’ experience children with intussusception can also present as being very still and less interactive than normal but with almost normal observations. Parents have noticed a change in their child’s constitution and this requires close consideration – the differential for this type of presentation is broad and beyond the aim of this article. 

If a child is severely unwell they may need urgent surgery so resuscitate as normal and call the paediatric surgeons if there are concerns with the abdomen. Abdominal XR is not always a requirement but is helpful to look for obstruction. If you can’t get an ultrasound done in your centre or the child is unstable then your surgical colleagues will accept the transfer for investigation.

Things that make intussusception more likely are lymphadenopathy (recent viral illness – especially gastroenteritis), known polyps (from medical/family history) or recent intussusception.

Air or water enema reduction can be done in tertiary children’s hospitals (usually only in hours) by radiologists and carries a risk of failure or perforation, needing open surgery. Surgeons will organise and be present for this.

Top tips – Intussusception

  1. Don’t forget ‘D’ and ‘E’ when you are performing an A-E assessment in critically unwell children. That slightly distended abdomen can be the key to diagnosis.
  2. Intussusception can present in a myriad of ways and children can appear quite well. Consider this diagnosis in children that have had ‘funny turns’, episodic symptoms or ‘don’t look right’.
  3. Whilst an abdominal X-ray may not give you a diagnosis of intussusception it can be supportive of an obstructive cause and rule out button batteries/magnets that might alter the patient’s journey or support a more timely intervention. A normal abdominal X-ray does not rule out intussusception.
  4. Don’t forget, whilst intussusception is generally seen in children 6 months to 2 years. It can occur in older children where it is more likely to be due to an underlying pathology. Intussusception is also associated with Henoch-Schonlein Purpura (HSP).

Case 3. Cheung…

You have a coffee break and then come back to see your next patient.

Cheung is a 3 year old boy who has been having redness on wiping his bottom for 2 days. Today there was a lot of red liquid in the toilet bowl. Cheung is potty trained and his dad, Ken, states he passes stool about twice per week. When Cheung stools he sits for 30 minutes with an iPad and pushes quite hard and it’s usually quite painful. Occasionally he has a clear or brown stain in his pants.

Cheung has no medical or surgical history and has no allergies. He took lactulose for 2 months a year ago but now doesn’t take anything.

You examine Cheung, who looks very well and is chatty. Here are your findings…

A – No concerns

B – RR 20, SaO2 98%, no IWOBRed blood on tissue toilet paper.

C – Well perfused, HR 120, BP 100/75

D – Abdomen is soft and non-tender but there is fullness in the left lower quadrant. External inspection of Cheung’s anus is normal

E – No rashes or temperatures, neurologically no concerns.

Ken took a picture of the tissue after wiping Cheung’s bottom

You consider the differentials and chat to your senior who asks you about stool type. Ken states that his poo is a type 2 and sometimes 1 when you show him a stool chart.

You think that Cheung’s blood in stool is probably related to his straining and constipation but you ask for a surgical opinion given the presence of blood and the absence of a visible fissure.

The surgical team agree this sounds like a diagnosis of anal fissures secondary to constipation and the abdominal fullness was probably faeces. They advise discharge with advice for constipation management with safety netting and outpatient surgical referral if symptoms don’t settle.

You give constipation advice about diet, dedicated daily ‘toilet time’, optimising the toilet environment and giving rewards. You discuss optimal pelvic positioning such as using a stool and keeping the knees above the horizontal. You commence Movicol to deal with the hard stools and suggest this gets reviewed with the GP in 1 month. Explain they may need to escalate the laxatives or have rectal therapy in future if it isn’t improving. You safety net and caution about more bleeding once the constipation is managed as there could be another cause.

Top Tips – Constipation

Constipation in children is a multifactorial issue that needs to be tackled early to avoid a spiral of symptoms throughout childhood. It can be due to slow intestines, hard faeces or rectal hold-up and the therapy should target the issue.

ERIC has loads of really helpful information and guidance.

The page on disimpaction is particularly helpful A parent’s guide to disimpaction – ERIC

In cases of constipation it is worth having the GP involved to oversee care. In this case it would also be helpful to check on the resolution of the abdominal mass which you suspect to be faeces.

When an abdominal mass is felt in a young person with no previous history of constipation be vigilant and consider investigation with bloods and USS with alternative diagnoses in mind.

In this case, due to the blood – remember to advise the parents to monitor and return if symptoms are getting worse or not resolving.

Case 4. Eliza…

The next patient you see is Eliza who has been brought to ED by her dad Jaspreet. Eliza is 4 years old and has been having issues with some blood mixed with her stools on and off for the last 4 months. It was a bigger volume today and they haven’t yet seen the ‘specialist’ they were referred to so came A&E as they were worried.

The bleeding is with most stools but it’s a small volume and doesn’t cause any pain. It’s usually mixed and Eliza doesn’t have any constipation. When you ask Jaspreet about systemic features he explains that Eliza has had less energy lately and people have remarked she is pale.

Eliza has no past medical or surgical history. She takes no medicines and has no allergies. Her family and siblings are healthy.

You examine Eliza, noting she is very pale and Jaspreet agrees she wasn’t previously this pale.


B – RR 18, SaO2 99%

C – HR 100, BP 110/68, good perfusion,

D – Abdomen is soft and non-tender, anus normal, no rashes but pale skin and conjunctiva

E – Neuro normal, mobile

You consider the differentials and chat to your senior. 

You’re both worried about something long-standing that’s bleeding, like a polyp, but you can’t differentiate this from a Meckel’s clinically. So you take some bloods and speak to the paediatric surgical team.

Whilst awaiting the paediatric surgeons Eliza’s bloods come back and show a microcytic anaemia. After reviewing her, the surgeons feel that she may have a polyp because of the long history and the lack of profound bleeding episodes. They feel she would benefit from medical admission, work-up and discussion with gastroenterology.

On the ward the next day, the gastroenterology team agree this sounds like a polyp but would like to rule out a Meckel’s before giving an anaesthetic for a scope. They agree it doesn’t sound like a haemorrhoid or fissure with the lack of constipation in the history and chronic nature from your assessment. Eliza is discharged with iron supplements and dietary advice and an outpatient Meckel’s scan.

3 weeks later, the scan is negative and the gastroenterology team organise a day case colonoscopy to deal with any polyps and look for evidence of a hereditary polyposis syndrome, they take biopsies of anything abnormal. Eliza will be seen and followed-up as an outpatient, when they will monitor iron levels and do any other investigations. They will involve the surgical team if no polyp is found or if an elective bowel resection is required later on. If multiple polyps are found she may undergo genetic testing alongside other young family members.


This is a rare chronic presentation to ED that can’t easily be differentiated from constipation, Meckel’s Diverticulum, internal fissure or intestinal vascular malformation. If you think the patient can go home then speak to the surgeons or medical team – they will arrange admission or urgent outpatient investigations and follow-up. Paediatric gastroenterology is rarely a 24/7 service so as long as the patient is safe then the discussions can happen in-hours by the paediatricians/surgeons, who are always available for advice and planning. Polyps are tricky as they carry a malignant risk and can’t be found on standard lower GI endoscopy so often need lots of follow-up.

BloodLarge volume, mixedSmall volume, mixed/separate
Symptom durationDays/WeeksWeeks/Months
Family HxNone50%
AdmissionOftenUsually OP follow-up
HbNormally normocyticMicrocytosis common
Prevalence2% (common)<0.001% (uncommon)
Presenting unwellSometimesRarely

Top Tips – Polyps

Polyps are rare but around 50% are associated with a family history so always ask.

Remember PR bleeds may be medical or surgical. Some patients may not reach a diagnosis in ED and instead require admission to have input from both teams.

Case 5. Magda…

Magda is 3 months old. Magda has been brought to A+E by her mother Francesca who is very concerned as she seen blood mixed with loose stool in the nappy. Francesca tells you that Magda has been quite unsettled during and after feeding and thinks she has pain in her abdomen. Magda has had milky vomit post feeds and has had explosive loose stool for the past 3 weeks. She has patches of dry skin for which the GP has recommended an emollient. Magda is bottle fed with cow and gate formula and takes 90mls 3 hourly. Magda was born on the 50th centile for weight but is now on the 25th centile. On examination she is currently settled with observations within normal limits for her age.

Blood in stool – September 2019 Babies | Forums | What to Expect

A – Patent

B – Good air entry bilaterally, no wheeze/crackles, no increased work of breathing

C – Warm and well perfused, CRT < 2 secs, normal heart sounds, femoral pulses palpable bilaterally

D – PEARL, good tone, AF open and soft.

E – Abdomen is soft, non-tender, BS present, some peri-anal redness, skin has dry erythematous patches all over.

You consider the differentialsl and discuss the case with your senior who also reviews Magda. Together you think the most likely cause for Magda’s symptoms is Cow’s Milk Allergy.. You discuss the types of Cow’s Milk Allergy which are classified according to the immune mechanism and timing of symptoms…

  1. Immunoglobulin (Ig)E Mediated: Develop serum specific IgE antibody. Produces immediate and consistently reproducible symptoms e.g. urticaria, vomiting, diarrhoea but may affect multiple systems. Reactions occur up to 2 hours after cow’s milk protein ingestion but usually within 30 minutes.
  2. Non-IgE-mediated: involves a T cell-mediated mechanism and reactions are typically delayed. They usually occur between 2 hours and 3 days after cow’s milk exposure.
  3. Mixed IgE and non-IgE: mixture of both IgE and non-IgE responses and are typically delayed.

Because Eliza is exclusively formula fed you prescribe a specialist formula after referring to your local guidance (usually Nutramigen or SMA Alfamino – depending on age and severity of symptoms). In addition you write to the GP to inform them of the need for an ongoing prescription and to monitor Eliza’s weight and progress. Follow up will depend on symptom severity, diagnosis and regional variation.

You advise Francesca that changes the prescription milk should be trialled for at least 4 weeks with follow up from GP at the end of this period. If there are concerns about failure to thrive then the GP should consider a referral for a Paediatric Outpatient review.

Top tips – Cow’s Milk Allergy

Symptoms of Cow’s Milk Allergy have considerable overlap with Gastro-oesophageal reflux (GOR) and ‘normal’ baby symptoms i.e. crying, posseting, being unsettled.

Take your time to listen to the parents’ concerns and if everything is reassuring then say so. If you’re not sure then discuss the case with an appropriate colleague.

Always check the weight and plot it on a centile chart! Weight loss or poor weight gain may indicate underlying pathology and the need for an intervention.

A+E clinicians – try not to intervene in plans for patients that already have follow up. Changing milks or adding in medications can confuse the situation unnecessarily. Where there is concern you could contact the team overseeing the patient’s care before making any changes.

Check out the further reading resources below for guidance on the investigation and management of Cow’s Milk Allergy.

Case 6. Steffan…

Your next patient is 4 year old Steffan. He has been brought to ED by his mother Lydia. Steffan presented one week ago to the Children’s Emergency department with a 2 day history of vomiting and diarrhoea. Observations and examinations were reassuring so they were discharged with presumed viral gastroenteritis. Lydia has brought Steffan back today as there is now blood mixed with his diarrhoea and she is concerned that he has not passed urine in the last 12 hours. Steffan has a fever, is still vomiting and complains of crampy abdominal pain. On examination he appears pale and lethargic with dry lips. When you examine Steffan you find…

A – Patent

B – Normal air entry bilaterally, no wheeze/crackles

C – Slightly cool peripherally, CRT 2-3 sec, HS normal

E – Abdomen soft, generalised tenderness, BS active, BM 4.2

D – PEARL, moving all 4 limbs

You think through the causes of bloody diarrhoea in children. Then ask Lydia if they have travelled anywhere recently. She says that they went to visit grandparents who took her son on an outine to a local petting farm, and his symptoms started a couple of days after that.

You wonder if this could be a case of Haemolytic Uraemic Syndrome (HUS) and have a chat with your consultant. Together, you agree that bloody diarrhoea requires investigation and decide to do some blood tests, send a stool sample for culture and perform a urine dip. 

Steffan has his investigations and is started on some maintenance IV fluids then admitted to the Paediatric ward.

You follow up his case and see that he was slightly anaemic with low platelets and an eventual diagnosis of HUS was made. He remains under the care of the Paediatric renal team.

Top tips – HUS

Bloody diarrhoea has a wide differential and careful thought needs to be given even in cases where the child appears well. We’d recommend having a low threshold for doing bloods – HUS can be devastating and is important not to miss.

Salmonella, Shigella and E.coli (both HUS and non-HUS provoking types) needs consideration and stool samples should be sent – there are Public Health implications in all of these cases.

Where renal failure is detected involve the General Paediatric team promptly. The differential still remains broad and if further conversations with specialists are required then the ward team would be best placed to have them. 


In this article we’ve discussed some of the different types of ‘Blood PR’ presentations we see in Paediatric A&E. By no means have we covered them all. Take a look at the further reading below for more information on this topic.

A particularly good resource is (BMJ ADC – 15 Minute Consultation – Rectal bleeding in children) . The authors have kindly given us permission to share the flowchart below – great for a practical approach in A&E. You can access via RCPCH or Open Athens (if you work in the NHS you should be able to access via your Open Athens account – set one up if you don’t already have one https://openathens.nice.org.uk/ )

Flowchart reproduced with consent of Jordan Evans and BMJ (many thanks) – here is a link to their great summary paper Fifteen-minute consultation: Rectal bleeding in children | ADC Education & Practice Edition (bmj.com)

Further reading and resources you may find helpful


Dr Sean O’Donnell. Registrar in Paediatric Surgery; Dr Suzie Johnson. Registrar in Paediatric Emergency Medicine; Dr Vikram Baicher, PEM Consultant; Ms Nia Fraser. Consultant in Paediatric Surgery. All Authors affiliated to Queens Medical Centre, Nottingham, UK

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