SINGAPORE - A large local study of polyclinic patients has found that not all the antibiotics used to treat urinary tract infections (UTIs) were as appropriate, and there was a need for better diagnosis and management of the condition in primary care.
Two out of four antibiotics that are usually prescribed for uncomplicated UTIs were found to be more superior and resulted in a lower risk of treatment failure. Patients were less likely to return to the clinic due to persistent symptoms or head to the emergency department because of complications.
A UTI is usually caused by bacteria, and the symptoms include pain when urinating, increased frequency of urination, and cloudy urine.
The infection is very common – about half of all women will experience it at least once in their lifetime.
The study from 2019 to 2021 involved 3,194 female patients, aged 18 to 50, with uncomplicated UTIs at six National University Polyclinics.
Uncomplicated UTIs occur in healthy people with normal urinary tracts. Complicated UTIs, which may require longer or stronger antibiotic courses, were excluded from the study.
This was the first large-scale local study in primary care done on uncomplicated UTIs in Singapore. Titled “Antibiotic treatment failure of uncomplicated urinary tract infections in primary care”, it was published in the journal Antimicrobial Resistance And Infection Control on Aug 1.
The study recommends using amoxicillin-clavulanate (commonly known as Augmentin) or nitrofurantoin for treating uncomplicated UTIs in Singapore.
These are antibiotics with lower reported resistance rates, and have lower treatment failure rates compared with ciprofloxacin and co-trimoxazole, said the study’s first author, Dr Sky Koh, an associate consultant and family physician at Bukit Batok Polyclinic.
He said patients who took Augmentin or nitrofurantoin were 33 per cent less likely to experience treatment failure, compared with those who took the other two antibiotics.
“You might not be able to clear the bacteria in the urinary tract altogether using the other two antibiotics because the bacteria have become more resistant to them over the years,” he said.
Dr Koh said the other significant finding was that doctors relied on urine tests to diagnose UTIs, even though international guidelines recommend diagnosing the condition based on symptoms only. In the study, only 26 per cent of the UTIs were diagnosed based on symptoms.
The guidelines also do not recommend collecting urine cultures for lab tests to diagnose uncomplicated UTIs, but local doctors do so for about one-third of the cases.
A urine test will tell if a person has a UTI, while a lab test on urine cultures will identify which bacteria are growing, and this will help doctors decide which antibiotics to prescribe.
“Most of the time, UTIs can be diagnosed in an uncomplicated way in non-pregnant women, pre-menopausal women between the ages of 18 and 50. It’s actually quite common and we can use symptoms to diagnose them,” said Dr Koh.
“We usually don’t send urine cultures because the tests cost $40 and the bacterium is going to be what we have predicted, which is Escherichia coli,” he said.
Escherichia coli is the most common culprit of UTIs, found in nearly 65 per cent of positive urine cultures in this study.
“If we can follow guidelines on when urine tests should be done, and the most appropriate antibiotic to prescribe, we can reduce costs and improve outcomes,” said Dr Koh.
The study also highlighted several issues. One of it was that outdated guidelines (released in 2006) had contributed to a lack of direction in antibiotic prescriptions for UTIs in primary care, he said.
Bacterial resistance development, a lack of antimicrobial stewardship in primary care compared with the hospitals, as well as difficulties that clinics face in stocking different antibiotics are among other factors that affect the landscape.
“Patients’ requests for antibiotics and how each individual handles them could also be another reason,” he said.
Dr Koh, who is part of an expert group advising the Ministry of Health on the development of clinical guidance for the diagnosis of UTI and on the outpatient antibiotic use for UTI, said an updated set of national guidelines is expected to be out by the end of the year.
