Children with urinary tract infections (UTIs) may improve clinically, and pyuria may resolve, during empiric treatment with an antibiotic that turns out to be discordant, according a retrospective study in Pediatrics.
M. Alexander Otto
Dr. Marie Wang
“The low rate of care escalation and high rate of clinical improvement while on discordant antibiotics suggests that, for most patients, it would be reasonable to continue current empiric antibiotic practices until urine culture sensitivities return,” said first author Marie E. Wang, MD, a pediatric hospitalist at Stanford (Calif.) University, and colleagues.
The researchers examined the initial clinical response and escalation of care for 316 children with UTIs who received therapy to which the infecting isolate was not susceptible. The study included patients who had infections that were resistant to third-generation cephalosporins – that is, urinalysis found that the infections were not susceptible to ceftriaxone or cefotaxime in vitro. Before the resistant organisms were identified, however, the patients were started on discordant antibiotics.
Escalation of care was uncommon
The patients had a median age of 2.4 years, and 78% were girls. Approximately 90% were started on a cephalosporin, and about 65% received a first-generation cephalosporin. Patients presented during 2012-2017 to one of five children’s hospitals or to a large managed care organization with 10 hospitals in the United States. The investigators defined care escalation as a visit to the emergency department, hospitalization, or transfer to the ICU.
In all, seven patients (2%) had escalation of care on discordant antibiotics. Four children visited an emergency department without hospitalization, and three children were hospitalized because of persistent symptoms.
Among 230 cases for which the researchers had data about clinical response at a median follow-up of 3 days, 84% “had overall clinical improvement while on discordant antibiotics,” the authors said.
For 22 children who had repeat urine testing while on discordant antibiotics, 53% had resolution of pyuria, and 32% had improvement of pyuria, whereas 16% did not have improvement. Of the three patients without improvement, one had no change, and two had worsening.
Of 17 patients who had a repeat urine culture on discordant therapy, 65% had a negative repeat culture, and 18% grew the same pathogen with a decreased colony count. Two patients had a colony count that remained unchanged, and one patient had an increased colony count.
Small studies outside the United States have reported similar results, the researchers noted. Spontaneous resolution of UTIs or antibiotics reaching a sufficient concentration in the urine and renal parenchyma to achieve a clinical response are possible explanations for the findings, they wrote.
“Few children required escalation of care and most experienced initial clinical improvement,” noted Dr. Wang and colleagues. “Furthermore, in the small group of children that underwent repeat urine testing while on discordant therapy, most had resolution or improvement in pyuria and sterilization of their urine cultures. Our findings suggest that Additionally, given that these patients initially received what would generally be considered inadequate treatment, our findings may provide some insight into the natural history of UTIs and/or trigger further investigation into the relationship between in vitro urine culture susceptibilities and in vivo clinical response to treatment.”