ATLANTA – A short course of IV antibiotics – 7 days or less – is fine for most infants with uncomplicated bacteremic urinary tract infections, according to a review of 116 children younger than 60 days.
How long to treat bacteremic UTIs in the very young has been debated in pediatrics for a while, with some centers opting for a few days and others for 2 weeks or more. Shorter courses reduce length of stay, costs, and complications, but there hasn’t been much research to see whether they work as well.
The new investigation has suggested they do. “Young infants with bacteremic UTI who received less than or equal to 7 days of IV antibiotic therapy did not have more recurrent UTIs,” compared “to infants who received longer courses. Short course IV therapy with early conversion to oral antibiotics may be considered in this population,” said lead investigator Sanyukta Desai, MD, at the Pediatric Hospital Medicine meeting.
The team compared outcomes of 58 infants treated for 7 days or less to outcomes of 58 infants treated for more than 7 days at 11 children’s hospitals scattered across the United States.
Urine was collected by catheter, and each child grew the same organism in their blood and urine cultures, confirming the diagnosis of bacteremic UTI. Children with bacterial meningitis, or suspected of having it, were excluded. The subjects had all been admitted through the ED.
There was quite a bit of variation among the 11 hospitals, with the proportion of children treated with short courses ranging from 10% to 81%.
As for the results, two patients in the short-course group (3%) and four in the long-course group (7%) had recurrent UTIs within 30 days. None of them developed meningitis, and none required ICU admission. Propensity-score matching revealed an odds ratio for recurrence that favored shorter treatment, but it wasn’t statistically significant.
The mean length of stay was 5 days in the short-course arm and 11 days in the long-course arm. There were no serious adverse events within 30 days of the index admission in either group.
Among the recurrences, the two children in the short-course arm were initially treated for 3 and 5 days. Both were older than 28 days at their initial presentation, and both had vesicoureteral reflux of at least grade 2, which was not diagnosed in one child until after the recurrence. The other child had been on prophylactic trimethoprim/sulfamethoxazole before the recurrence.
The four recurrent cases in the long arm initially received either 10 or 14 days of IV antibiotics. Two children had grade 4 vesicoureteral reflux and had been on prophylactic amoxicillin.
Infants treated with longer antibiotic courses were more likely to be under 28 days old, appear ill at presentation, have had bacteremia for more than 24 hours, and have and grow out pathogens other than Escherichia coli. The two groups were otherwise balanced for sex, prematurity, complex chronic conditions, and known genitourinary anomalies.
With such low event rates, the study wasn’t powered to detect small but potentially meaningful differences in outcomes, and further work is needed to define which children would benefit from longer treatment courses. Even so, “it was reassuring that patients did well in both arms,” said Dr. Desai, a clinical fellow in the division of hospital medicine at Cincinnati Children’s Hospital.
“At our institution with uncomplicated UTI, we wait to see what the culture grows.” If there’s an oral antibiotic that will work, “we send [infants] home in 3-4 days. We haven’t had any poor outcomes, even when they’re bacteremic,” she said.
The work was funded by the National Institutes of Health. The investigators didn’t have any disclosures.