Reasons for having a urine test
Testing a sample of your child's urine (wee) is the only way to know for sure if they have a urinary tract infection (UTI). Sometimes a urine sample is needed to check for kidney problems.
Urinary Tract Infection In Children
How urine samples are collected in children
Mid-stream urine sample for children out of nappies
Tamariki (children) who are out of nappies and can wee when asked will normally provide a mid-stream urine (MSU) sample.
Other ways of getting a sample in younger children
In younger tamariki who are in nappies and cannot wee on request, an MSU is usually not possible. There are a few different ways to get a urine sample, including:
- clean catch
- bag collection - if a UTI is suspected this is the least reliable method
- catheter sample
- SPA (suprapubic aspirate)
For all urine samples, regardless of how they are collected, make sure to write on the container. Things to write on the container include:
- your child's first name and surname
- your child’s date of birth
- the date and time you collected the sample
It is important that the urine sample is fresh when tested so try to take it to the laboratory within 2 hours or put it in the fridge (not the freezer) until you can deliver it.
Mid-stream urine (MSU) sample
To collect an MSU, follow these steps.
Your child needs to start doing wee into the toilet.
Catch some of the middle part of the urine stream in a sterile container (from your health professional).
You don't need a large amount so your child can then finish doing wee into the toilet.
Clean catch
Collecting a clean catch sample involves 'catching' a sample of clean urine from a baby or young child as they wee. Follow these steps.
Give your baby a drink or breastfeed to help fill the bladder.
Clean your child's genital area with soap and water.
Leave your child's nappy off and wait for them to wee and quickly catch a small amount in a sterile container (from your health professional).
It can be difficult to time catching a wee - you may need to make several attempts. This can be time-consuming and often not practical when pēpi (babies) are unwell.
A clean catch is only really practical to do in pēpi who are not yet mobile and so can lie still on their backs. Sometimes, healthcare staff may show you how to gently tap on the lower part of your baby's tummy to encourage your baby to wee.
Bag collection
To collect a bag collection sample, follow these steps.
Clean your child's genital area with soap and water.
Attach the special plastic bag, which has a sticky strip, over your baby's genital area. For boys, the entire penis can go in the bag; for girls, the bag goes over the labia.
You can put your baby’s nappy on over the bag.
Urine collects in the bag when your baby wees. Sometimes it can take several attempts to get some wee.
Transfer the urine sample from the bag into the sterile container (from your health professional).
Don't leave the bag on overnight - if your child has not done a wee after 4 hours, put on another bag.
A bag urine sample is often contaminated by germs from the skin - this can make it look like your child has a UTI even if they don't really. Bag collection is the least reliable way of collecting a urine specimen in a baby.
If the result indicates a possible UTI, your child will need a sterile urine sample taken directly from the bladder to confirm the result.
Sterile urine collection methods
Sterile urine collection methods are the best way to accurately diagnose a UTI. These include:
- catheter sample
- SPA (suprapubic aspirate)
Catheter sample
A catheter sample is taken by a health professional.
The health professional passes a fine plastic tube (a catheter) through the urethra into the bladder so that they can collect a urine sample into a sterile container - the urethra is the tube from which urine passes out of the bladder.
Your child needs to lie down with their ankles held together to make sure the catheter goes in cleanly - pēpi and young tamariki may not like being held in this position, but it only takes a few minutes
The test is uncomfortable - you should reassure and comfort your child during the test.
SPA (suprapubic aspirate)
A suprapubic aspirate is taken by a health professional.
Your child lies down on their back and needs to be held still. The health professional cleans the area well and then puts a small needle through the skin of the lower part of your child’s tummy and into the bladder. Urine is collected straight from the bladder via the needle into a syringe.
SPAs are a very safe test and problems are rare. In terms of pain for your child, it is similar to having a blood test.
How urine samples are tested
A quick 'dipstick' (test strip) by your health professional provides clues
Your health professional will usually test the urine sample with a 'dipstick' (test strip) first. This can provide clues about whether your child may have a UTI.
Only the laboratory can give a final diagnosis by doing a 'culture'
There is only a final diagnosis once the urine sample goes to the laboratory. Staff there do a 'culture' - laboratory staff see if any bacteria grow from your child’s urine sample. They do this by adding the urine sample to a special gel.
If bacteria grow, the laboratory staff can identify what kind of bacteria it is. Health professionals can then decide which antibiotics to use to kill it. Culture results may take 24 to 48 hours.
If the dipstick test suggests a UTI, treatment usually starts before the culture results are available. The diagnosis and treatment may change once the culture results come back from the laboratory.
