Introduction

A white blood cell (WBC) scan is an imaging test that helps find infection or inflammation in your child’s body. 

The test shows doctors where white blood cells are travelling. This can help understand where there is swelling or inflammation and how your child’s immune system is responding.

It uses: 

• a Gamma camera – a large camera that measures radiation
• radiotracer- a small amount of radioactive fluid that moves through the body

The gamma camera takes pictures of the radiotracer as it moves through your child’s body, helping doctors see where white blood cells are going. 

A white blood cell scan can be done to diagnose or check conditions like:

• inflammatory bowel disease (IBD)- swelling or irritation of the bowel, the lower part of the digestive system
• crohn’s disease – an ongoing condition that causes inflammation in the lining of the intestines
• osteomyelitis- a bone infection caused by bacteria
• abscesses- infected or swollen areas that may be filled with pus
• pyrexia of unknown origin (PUO)- an ongoing fever with no clear cause
• other inflammatory conditions.

Your child can eat and drink normally before the scan. Your child will be weighed to help calculate the correct amount of radiotracer.

The risks of radiation and allergic reactions are very low. Let your child’s treatment team know if they have any allergies. 

Your child will not feel anything during the scan, and the camera will not touch them. 

 The scan takes about five hours and is completed in four parts.

You can stay with your child. You may need to briefly leave the room if your child needs the additional X-ray scan.   

Generally, the steps of the scan are:

Part 1: 

1. a small amount of blood is taken with a small ‘butterfly’ needle
   • if your child has a central line, this may be used instead
2. the nuclear medicine team will mix the radiotracer with the blood
3. you and your child will return to the department about 1.5 hours later for the next step.

Part 2:

1. the blood mixed with radiotracer is gently injected back into your child using a butterfly needle
   • if your child has a central line, this may be used instead
2. you and your child will return to the department again about one hour later for imaging

Part 3:

1. your child will lie on the scanning bed
2. a blanket with velcro straps may be used to help keep your child still
3. the camera will take pictures of your child’s neck and tummy for about 15 minutes
4. you and your child will return to the department again about two hours later for imaging.

Part 4:

1. your child will lie on the scanning bed
2. a blanket with velcro straps may be used to help keep your child still
3. the camera will take more detailed pictures of the tummy over about 45 minutes, moving around your child to get different views.

The nuclear medicine team will let you know if you need further scans.

You can leave once the images are checked by a doctor or nuclear medicine scientist.

The results will be sent to your child’s doctor within a couple of days. You will need to schedule a follow-up appointment with your child’s doctor to discuss the results.