Urinary tract infection, children - Diagnosing UTIs in children

If your child has symptoms of a urinary tract infection (UTI), a sample of their urine will be tested.

Your GP may also carry out a physical examination of your child and ask if they have a history of bladder or kidney problems.

This will help your GP identify what is causing the infection and determine whether it is in the lower or upper part of the urinary tract.

Collecting a urine sample

You may be asked to collect the urine sample yourself, or a doctor or nurse at your GP surgery may help you. If your child is less than three months old, your GP may refer you straight to hospital to see a paediatrician (a specialist in caring for children) without asking for a urine sample.

Collecting a urine sample from a child can sometimes be difficult, especially in babies and young children. If you are not sure what to do or need some help in collecting the urine sample, ask a doctor or nurse for advice.

In young children who are toilet trained, you will usually be asked to collect a urine sample using a sterile bottle provided by your GP surgery. Collect a sample by holding the bottle in the stream of urine while your child is urinating. Make sure nothing touches the open rim of the bottle, as this could affect the result.

If you are unable to collect a clean sample, it may be collected using a special absorbent pad that you put in your baby's nappy. A urine sample is then sucked out of the pad using a syringe.

If a urine sample is very difficult to collect at home or in a GP surgery, you may need to go to a hospital. In such cases, a urine sample can be obtained by inserting a small plastic tube called a catheter into your child’s urethra.

Further tests

In many cases, treatment will start soon after a urine sample has been taken, and your child will not need to have any further tests.

However, there are some circumstances where further tests may be carried out, including if:

• your child is less than six months old
• there is no improvement in your child's symptoms within 24 to 48 hours of treatment
• your child has any unusual symptoms, such as reduced urine flow, high blood pressure (hypertension), or a noticeable lump or mass in their tummy (abdomen) or bladder
• your child has repeated UTIs

In these cases, doctors may recommend carrying out some scans to look for any abnormalities.

Scans

There are many different scans that may be carried out to check for problems in your child's urinary tract, including:

• an ultrasound scan – where sound waves emitted by a special probe move over your child's skin and are used to build up a picture of the inside of their body
• a dimercaptosuccinic acid (DMSA) scan – where your child is injected with a slightly radioactive substance called DMSA that shows up on a special device called a gamma camera. This takes pictures of your child’s kidneys; after the scan, the DMSA will pass harmlessly out of your child’s body, in their urine
• a micturating cystourethrogram (MCUG) – where a catheter is used to pass a special type of liquid (contrast agent) that shows up clearly on X-rays into your child's bladder, while a series of X-rays are taken; as with the DMSA scan, the contrast agent will pass harmlessly out of your child’s body, in their urine

The type of scans used and when they are carried out will depend on your child's specific circumstances. In some cases, these scans may be carried out a few weeks or months after your child originally developed the infection.