Antimicrobial resistance is an internationally recognised threat to health. Throughout the world, children are frequent consumers of antibiotics – and such routine use has been shown to increase the probability of antibiotic resistance in adults with urinary tract infections. 

However, little is known about the prevalence of bacterial resistance in children, or the risk factors of importance in this group.

Researchers from University of Bristol and Imperial College London reviewed studies investigating the prevalence of antibiotic resistance in urinary tract infections caused by Escherichia coli, a bacterium responsible for over 80 per cent of all urinary tract infections in children. They also set out to measure the association between previous exposure to antibiotics and subsequent resistance in the same child.

They reviewed the results of 58 observational studies in 26 countries involving over 77,000 E. coli samples. Although they cannot tell us about cause and effect, using a technique called meta-analysis involving observational data is useful for pulling evidence together.

The results, published by The BMJ today, show a high global prevalence of antibiotic resistance, to some of the most commonly prescribed antibiotics in primary care, in urinary tract infections in children caused by E coli.

Results were categorised by the OECD (Organisation for Economic Co-operation and Development) status of the study country as antibiotics tend to be used differently in these groups. Within OECD countries, half of all samples were resistant to ampicillin (amoxicillin), a third to co-trimoxazole, and a quarter to trimethoprim. Resistance was substantially greater in non-OECD countries.

Lead author Ashley Bryce, a PhD student at the Centre for Academic Primary Care at the University of Bristol said: "Prevalence of resistance to commonly prescribed antibiotics in primary care in children with urinary tract infections caused by E coli is high, particularly in countries outside the OECD, where one possible explanation is the availability of antibiotics over the counter."

Dr Céire Costelloe, from the Health Protection Research Unit (NIHR HPRU) in Healthcare Associated Infections and Antimicrobial Resistance at Imperial College London, co-led the research. She said: "The results also suggest previous antibiotic use increased the subsequent risk of E coli resistance to that particular antibiotic – for up to six months after treatment."

Paper

'Global prevalence of antibiotic resistance in paediatric urinary tract infections caused by Escherichia coli and association with routine use of antibiotics in primary care: systematic review and meta-analysis' by Bryce, Hay, Lane, Thornton, Wootton & Costelloe in The BMJ.