Understanding your child’s IBD tests and results

Blood tests, stool tests, scans and procedures can all be part of your child’s IBD journey. Here’s what the most common tests are looking for and what the results can tell you.

If your child has been diagnosed with inflammatory bowel disease (IBD), or is being investigated for Crohn’s disease or ulcerative colitis, you may suddenly find yourself hearing about tests you have never heard of before.

CRP. ESR. Faecal calprotectin. Haemoglobin. Ferritin. Colonoscopy. Biopsy. MRI.

It can feel like you’re trying to learn a whole new language.

The good news is that you don’t need to understand every number on your child’s pathology report.

Your child’s gastroenterology team looks at all the information together — symptoms, examination, growth, blood tests, stool tests, scans and procedures — to understand what is happening with their IBD.

This guide explains some of the most common IBD tests for children and what they can tell you.

🩸 Blood tests

Blood tests are commonly used when a child is being investigated for IBD and during ongoing monitoring.

They can provide information about:

• Inflammation

• Anaemia

• Iron levels

• Nutritional status

• Liver and kidney function

• Infection

• Your child’s general health

Your child may have blood tests regularly, even when they are feeling well.

That’s because blood tests can provide information about what is happening inside the body that isn’t always obvious from symptoms alone.

🔥 CRP — C-reactive protein

CRP stands for C-reactive protein.

It is a blood marker that can increase when there is inflammation in the body.

Your child’s gastroenterologist may use CRP to help assess how active their IBD is and whether inflammation appears to be improving with treatment.

However, CRP isn’t specific to IBD.

It can also increase with other causes of inflammation, including infections.

And importantly, a normal CRP doesn’t always mean that IBD inflammation isn’t present.

Your doctor will interpret the result alongside your child’s other tests and symptoms.

🧪 ESR — erythrocyte sedimentation rate

ESR is another blood test that can provide information about inflammation.

Like CRP, ESR is not specific to IBD.

Your child’s doctor may look at ESR together with CRP, symptoms and other results rather than relying on one number.

🩸 FBC or CBC

You may see FBC or CBC on your child’s blood test results.

FBC stands for full blood count, while CBC stands for complete blood count.

It measures different types of blood cells, including:

• Red blood cells

• White blood cells

• Platelets

One of the things doctors may be looking for is anaemia.

❤️ Haemoglobin

Haemoglobin is a protein in red blood cells that carries oxygen around the body.

A low haemoglobin level can indicate anaemia.

Children with IBD can develop anaemia for several reasons, including iron deficiency, inflammation or blood loss.

If your child’s haemoglobin is low, their doctor will look at the rest of their blood results to help work out why.

🧲 Ferritin and iron

Ferritin gives information about your child’s stored iron.

Iron levels can be affected by several factors, including inflammation, so your child’s doctor may look at a number of iron-related blood tests together.

These may include:

• Ferritin

• Serum iron

• Transferrin

• Transferrin saturation

• Haemoglobin

Iron deficiency and anaemia can occur in children with IBD, particularly when inflammation is active or there has been blood loss.

If your child has low iron, ask their healthcare team whether they need dietary changes or iron supplementation.

🧬 Other blood tests

Depending on your child’s situation, their doctor may also check:

• Albumin

• Electrolytes

• Liver function

• Kidney function

• Vitamin levels

• Vitamin B12

• Folate

• Vitamin D

• Zinc

• Other nutritional markers

Not every child needs all of these tests.

The tests your child has will depend on their symptoms, diagnosis, treatment and individual needs.

💩 Stool tests

Stool tests can provide useful information about what’s happening inside the digestive tract.

Your child may be asked to provide a stool sample during the initial investigation of IBD and periodically during treatment.

Two important reasons for stool testing are:

Checking for infection

Some infections can cause symptoms that look similar to an IBD flare.

Checking for intestinal inflammation

A test called faecal calprotectin can help doctors assess inflammation in the intestines.

🔬 Faecal calprotectin

This is a test you will probably hear about a lot if your child has IBD.

Faecal calprotectin is a protein found in certain white blood cells.

When there is inflammation in the intestines, calprotectin can be released into the stool.

A stool sample can therefore be tested for calprotectin to provide information about intestinal inflammation.

Doctors may use it to:

• Help investigate possible IBD

• Monitor known IBD

• Assess response to treatment

• Look for signs that inflammation may be increasing

• Help distinguish inflammatory conditions from some non-inflammatory causes of symptoms

What does a high result mean?

A high faecal calprotectin can indicate intestinal inflammation.

However, it doesn’t automatically mean your child is having an IBD flare.

Other conditions, including infections, can also increase calprotectin.

Your child’s gastroenterologist will interpret the result alongside their symptoms and other investigations.

What does a normal result mean?

A lower result can be reassuring, but it doesn’t always tell the whole story.

Your child’s doctor will consider the result alongside their clinical picture.

Don’t compare your child’s number with someone else’s number online.

The meaning of a result depends on the situation, the laboratory, your child’s age and the other information available to their healthcare team.

🩻 Imaging and scans

Sometimes your child’s doctor needs to look at parts of the digestive tract that cannot be fully assessed through a colonoscopy or endoscopy.

Depending on your child’s symptoms, they may recommend imaging such as:

• MRI

• MR enterography

• Ultrasound

• X-ray

• Other specialised imaging

🧲 MRI and MR enterography

An MRI uses magnetic fields and radio waves to create detailed images of the body.

MR enterography (MRE) is a type of MRI used to examine the small intestine and surrounding areas.

It can be particularly useful when doctors are investigating Crohn’s disease, which can affect parts of the small intestine.

MRI does not use ionising radiation.

Your healthcare team will explain how your child needs to prepare for the scan.

🩻 Ultrasound

An ultrasound uses sound waves to create images of the body.

Depending on the situation and the expertise available, intestinal ultrasound may sometimes be used to assess the bowel.

Your child’s gastroenterologist will decide whether an ultrasound is appropriate.

🔎 Endoscopy and colonoscopy

You may hear the terms endoscopy and colonoscopy used when your child is being investigated for IBD.

Upper endoscopy

An upper endoscopy, sometimes called a gastroscopy, allows doctors to examine the upper digestive tract.

It can look at areas such as the:

• Oesophagus

• Stomach

• Duodenum

Colonoscopy

A colonoscopy allows doctors to examine the:

• Rectum

• Colon

• Usually the end of the small intestine

These procedures allow the gastroenterologist to see the digestive tract directly.

🔬 What is a biopsy?

During an endoscopy or colonoscopy, the doctor may take tiny samples of tissue called biopsies.

A pathologist examines these samples under a microscope.

Biopsies can provide important information about inflammation and other changes in the digestive tract.

You may receive a pathology report containing terms you don’t recognise.

Don’t worry if you don’t understand it.

Your gastroenterologist will interpret the findings alongside the endoscopy, blood tests, stool tests and your child’s symptoms.

📊 Why can test results change?

One of the most confusing things for parents can be seeing test results go up and down.

That’s because IBD is not always static.

Inflammation can change over time, and test results can be affected by things such as:

• IBD activity

• Infections

• Medications

• Treatment response

• Nutrition

• Other illnesses

A single result usually doesn’t tell the whole story.

Your child’s gastroenterologist will often be more interested in patterns over time.

For example, they may compare your child’s faecal calprotectin results from several months apart rather than looking at one number in isolation.

📈 What does “trending” mean?

You may hear your doctor talk about trends.

This simply means looking at how a result changes over time.

For example:

January: higher inflammation marker

March: lower

June: lower again

This pattern may provide different information from one isolated result.

The same applies to your child’s growth, weight, symptoms and other measurements.

❤️ What if my child’s results don’t match their symptoms?

This can happen.

Your child might feel completely well while a test shows some inflammation.

Or your child might have significant symptoms while certain blood tests look normal.

This is why doctors don’t usually diagnose or monitor IBD based on one test alone.

Your child’s healthcare team considers:

Symptoms + examination + growth + blood tests + stool tests + imaging + endoscopy/biopsies

The combination provides a much clearer picture.

📝 Questions to ask about your child’s test results

You don’t need to understand every number yourself.

At your next appointment, you could ask:

• What do my child’s results show?

• Are there signs of active inflammation?

• Are their iron levels okay?

• Is their haemoglobin normal?

• What does their faecal calprotectin result mean?

• How does this result compare with their previous result?

• Are their nutritional levels okay?

• Is my child’s growth on track?

• Which results are you most interested in monitoring?

• When should these tests be repeated?

• What result would make you concerned?

• Do these results suggest that their treatment is working?

And one particularly useful question:

“Can you explain which results matter most for my child?”

You don’t need to understand every number on the page.

📱 Keep a record of your child’s results

If your child has IBD, you may eventually collect quite a few blood and stool test results.

Keeping a simple record can make it easier to see what’s happening over time.

You could keep a note with:

Date

Faecal calprotectin

CRP

ESR

Haemoglobin

Ferritin

Weight

Height

Symptoms

You don’t need to interpret the numbers yourself.

The purpose is simply to have the information available when you speak with your child’s healthcare team.

🚩 When should I contact the IBD team?

Test results are only one part of monitoring your child’s health.

Contact your child’s healthcare team if you are concerned about new or worsening symptoms, particularly:

• Increasing diarrhoea

• Blood in the stool

• Persistent abdominal pain

• Significant fatigue

• Reduced appetite

• Weight loss

• Fever

• Dehydration

• Increasing urgency or frequency of bowel movements

• New symptoms that are unusual for your child

Your child’s IBD team should give you specific advice about when they want you to contact them and what to do if symptoms suddenly worsen.

💛 Don’t let the numbers overwhelm you

It can be frightening to see a result marked “high” or “low” on your child’s pathology report.

But a number on its own doesn’t tell you how your child is doing.

Your child’s doctor looks at the whole picture and considers their symptoms, growth, examination and results together.

And if you don’t understand something, ask.

You can say:

“What does this result mean for my child?”

That’s often a much more useful question than simply asking whether a number is normal.

Over time, you’ll become more familiar with the tests your child has regularly.

For now, you only need to understand what matters for your child at this point in their IBD journey.