Children who are given antibiotics are more likely to develop resistance to common drugs used to treat urinary tract infections, according to research published this week.

A new study published in the British Medical Journal (BMJ) shows drug-resistant E. coli urinary tract infections (UTIs) are on the rise in children.

According to the National Institutes of Health (NIH), UTIs account for about 1 million pediatrician visits every year.

Girls are four times more likely to develop a UTI, and uncircumcised newborns are more likely to develop a UTI than circumcised infants.

Typically treated with common, inexpensive antibiotics, new strains of E. coli that are resistant to these types of medications are slowly emerging and creating problems with treatment.

“Our findings detail global high-level resistance to some of the most commonly prescribed antibiotics for children’s primary care, which could result in several drugs becoming ineffective first line treatments in many countries,” the researchers noted in their study.

Drug-resistant bacteria are a global concern. Major medical organizations, such as the U.S. Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO), have declared the issue an epidemic that needs immediate attention.

In the United States, 2 million people a year are infected with antibiotic-resistant bacteria. About 23,000 of these cases are fatal, according to CDC estimates.

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How Drug-Resistant Bacteria Infect Children

To study the prevalence of antibiotic-resistant bacteria in children, researchers with the University of Bristol, University Hospital of Wales, and Imperial College London assessed E. coli isolated from 77,783 samples. These samples were collected from 58 observational studies conducted in 26 countries.

They found half of the bacteria were resistant to ampicillin and a third were resistant to co-trimoxazole. Also, one quarter was resistant to trimethoprim, three antibiotics used to treat UTIs and other common infections. All are on the WHO List of Essential Medicines, or necessary drugs a country needs to provide basic medical care.

So how do children’s immune systems develop resistance to these bacteria?

E. coli lives naturally in our guts. Inside our bodies, these bacteria help keep the natural balance needed to digest foods, metabolize calories, and help keep our immune systems healthy.

When these and other bacteria are exposed to nonlethal doses of antibiotics, such as not taking a full course of a prescription, they can develop resistance.

Unnecessary prescriptions, such as using antibiotics for the common cold, also drive resistance. According to the latest CDC estimates, half of the antibiotic prescriptions in outpatient settings are not necessary.

When outside the body — whether through feces or contamination from animal sources — drug resistant bacteria, such as E. coli and other dangerous forms, can create a variety of infections, including UTIs.

Relative to the UTIs in the BMJ study, researchers found the drug-resistant E. coli remained with children for up to six months after receiving antibiotics.

In some less developed countries where antibiotics are available over the counter, researchers found drug-resistant UTIs in greater numbers.

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Preserving the Effectiveness of Antibiotics

As bacteria evolve around current antibiotics, making it harder for them to do so is an important approach to fighting even the simplest of infections.

Grant Russell, professor at the School of Primary Health Care at Monash University in Melbourne, Australia, wrote in an editorial accompanying the BMJ study that there’s “compelling evidence” that current approaches to pediatric UTI treatment need to be reconsidered.

“While I have no doubt that clinical practice guidelines will quickly be able to accommodate the findings, I am less confident that there is the will and commitment to deal with what the WHO has called ‘the postantibiotic era,’” he concluded.

Dr. Amesh A. Adalja, an infectious disease physician at the University of Pittsburgh Medical Center who was not associated with the BMJ study, says drug-resistant UTIs are more difficult to treat and may be more likely to first be treated with an ineffective medication.

“Ineffective medications could lead to more severe infections occurring with spread to the kidneys and bloodstream,” he told Healthline. “Such consequences can lead to sepsis, septic shock, and higher morbidity and mortality.”

Adalja, echoing prevailing sentiment in the infectious disease community, says minimizing the use of unnecessary antibiotics and instilling the principles of good hygiene may help minimize the spread of drug-resistant bacteria in children.

“Judicious use of antibiotics is a cornerstone of good medical practice and an important means to slow down the rise of drug-resistant bacteria,” he said. “Antibiotics should be taken only when they are warranted and that will usually require consultation with a healthcare professional.”

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