What are the longer-term risks associated with urinary tract infection in children?

June 2024

It is thought that childhood urinary tract infection (UTI) increases the risk of developing renal scarring, hypertension (high-blood pressure), chronic kidney disease and end-stage renal failure.

However, this association is based on research conducted only in hospital settings, involving children who were seriously unwell or with other underlying risk factors in addition to a urinary tract infection.

This made it challenging for general practitioners to assess the risk posed to children experiencing milder cases of urinary tract infection and decide on ongoing investigation and management.

Researchers on the LUCI study (Long-term consequences of urinary tract infection in Childhood) wanted to find out if the results would differ if they widened the setting from hospital only to the general population.

To do this, the team looked at the incidence of urinary tract infections in all children born 2005-2009 to the age of 5 years old, and then used data from both primary and secondary care to assess the subsequent incidence of serious complications before the age of 10.

The data was provided by the Secure Anonymised Information Linkage (SAIL) Databank, a repository for routinely collected health and population data in Wales.

The results showed that children who are diagnosed with urinary tract infection in childhood do not have an increased risk of going on to develop chronic kidney disease (CKD), hypertension or end-stage renal failure (ESRF) by the age of ten.

Whilst the risk of renal scarring is increased for children with UTI, the risk is significantly lower than previously thought. Vesiocoureteral reflux disease (VUR), a UTI under the age of one, and three or more UTIs under the age of five, are risk factors for renal scarring.

Dr Kathryn Hughes, a GP clinical fellow from PRIME Centre Wales, Cardiff University who led the study comments:

“This is the first study to look at the risks following all childhood UTIs, including those with milder UTIs, and without additional underlying risk factors.

We found that even without underlying risk factors, children with UTI are more likely to be diagnosed with kidney scarring than those without, but kidney scarring was only diagnosed in approximately 1% of children following at least one UTI.

We found that childhood UTI, in the absence of other risk factors, was not associated with chronic kidney disease, high blood pressure or kidney failure up to age ten. This may mean that further imaging and follow-up of children with UTI but without additional risk factors is not necessary. However, longer follow-up studies are needed to confirm whether UTI is associated with these complications later in life." 

Further research with systematic scanning of children’s kidneys including those with less severe UTI and without UTI, is needed to increase certainty of these results, as most children are not scanned. Longer follow-up is needed to establish if UTI, without additional risk factors, is associated with hypertension, CKD or ESRF later in life.

This project has been funded by the Welsh Government through Health and Care Research Wales. PRIME Centre Wales receives funding from Health and Care Research Wales. The Centre for Trials Research receives funding from Health and Care Research Wales and Cancer Research UK.

Publication citation:
Kathryn Hughes, Rebecca Cannings-John, Hywel Jones, Fiona Lugg-Widger, Tin Man Mandy Lau, Shantini Paranjothy, Nick Francis, Alastair D Hay, Christopher C Butler, Lianna Angel, Judith Van der Voort and Kerenza Hood. Long-term consequences of urinary tract infection in childhood: an electronic population-based cohort study in Welsh primary and secondary care. British Journal of General Practice 2024; 74 (743): e371-e378. 

Read the publication in full at:
https://doi-org.abc.cardiff.ac.uk/10.3399/BJGP.2023.0174

Further information about the LUCI study can be found on the Centre for Trial Research webpages.