DMSA scan (children)

About a DMSA scan

Your child’s paediatrician has requested a DMSA scan. 

This is a special type of scan which takes pictures of your child’s kidneys. It checks how well their kidneys are working and checks for structural damage or scarring.

This information helps us diagnose and treat your child's condition.

We will discuss with you why your child might need this type of scan. Usually it is because a child has had multiple or severe urinary tract infections (UTIs). It can be because a child is born with kidneys that do not work properly.

How the scan works

We inject a small amount of radioactive tracer into your child’s vein, using a cannula. (A cannula is a thin, flexible tube with a small needle at the end.) This tracer is absorbed into their healthy kidney cells. We then use a special camera to take pictures of these kidney cells.

Preparing for your appointment

As soon as possible before your child’s test, let us know:

• if your child has had a urinary tract infection (UTI) during the 3 months before their DMSA scan. We will ask you for the date of their last UTI (if applicable).
• if you (the parent) are pregnant or may be pregnant
• if your daughter is having the scan, and she may be pregnant.

• Make sure your child is well hydrated (not thirsty) when they arrive. This helps the scan work effectively.  
• It is a good idea to bring along toys, books or an iPad or phone, to entertain your child during the scan. Download content to your device before you arrive. (The hospital's wi-fi is patchy).

During the appointment

The scan will take place in the Kingston Hospital Nuclear Medicine department. (We will direct you there after we see your child in Dolphin ward to fit their cannula - see below). You will be able to stay with your child throughout the appointment. 

The appointment consists of two parts, as follows.

• Insertion of the cannula and injection of the radioactive tracer. You will then have to wait for 2 to 4 hours while your child's body absorbs the tracer.
• The DMSA scan, which takes up to 30 minutes.

On the day

You can expect the following on the day.

Cannula insertion 

• In Dolphin ward, we will weigh your child. This is because we prepare the radioactive tracer according to their weight.
• We will apply numbing agent to your child's arm. This reduces discomfort when we insert the cannula into their vein. 
  • for young children, we apply numbing gel. This takes up to 30 minutes to work.
  • for older children we apply numbing cold spray. This works instantly.
• We will insert the cannula into your child's vein (usually in their hand or arm).
• We will direct you to the hospital's Nuclear Medicine department (close to Dolphin ward). You will have to wait there with your child for up to 30 minutes.
• We will inject the tracer into your child's vein, and remove the cannula.

It takes 2 to 4 hours for the tracer to be absorbed by the kidneys. During this time, you and your child can leave the hospital. We will give you a time to return for the scan.

DMSA scan

When you return to the Nuclear Medicine department, we will perform the DMSA scan, using the special camera. You can stay with your child during the scan.

Risks 

A DMSA scan is usually extremely safe, but we advise you to be aware of the following.

Radiation

A DMSA test involves your child being exposed to a small amount of radiation. The amount we use is the minimum necessary and it is considered to be safe for children. (It is equal to the amount they would receive from natural sources, over a period of 1 to 3 months). 

The radioactive tracer in your child’s body becomes inactive after a few hours. Their body ejects it in their wee (urine) or poo (faeces).

Discomfort

The insertion of the cannula may cause a little discomfort at first. We use a numbing gel or spray to keep this to a minimum.

Pregnancy

Radiation can harm an unborn baby.

If female children are 12 years or older, we may ask them (and you) if they might be pregnant.

If you (the parent) might be pregnant, or if you are breastfeeding, let us know as soon as possible before your child's test.

After the scan

If your child is not due to have further scans or tests, you and your child will be free to go home after the scan.

For the first 24 hours at home, do the following.

• Medications are not affected by the radioactive tracer. Continue with your child's regular medications.
• Encourage your child to drink plenty of fluids. This will help to flush the tracer out of their body quickly.
• Wash your hands thoroughly with soap and water after handling any of your child’s bodily fluids (wee, poo or vomit).
• Flush twice when your child uses the toilet. Wash your hands, and your child's hands, with soapy water.
• If your child uses a potty, flush the toilet twice after emptying it. Wash the potty with soapy water. Wash your hands, and your child's hands, with soapy water.
• If your child wears nappies, put used nappies in a separate bag for 24 hours before disposing of them. Wash your hands thoroughly afterwards.
• If you are pregnant or breastfeeding, avoid contact with your child and their bodily fluids (wee, poo or vomit).

Scan results

We will send a scan report to your child's GP. They will contact you with the scan results (by phone or letter).

Get in touch with the Paediatric Admin team if you still have not received the scan results 1 month after the scan (see Contacts).