The predictive utility of prior positive urine culture in children with recurrent urinary tract infections.

Urinary tract infections can cause renal damage if not treated promptly. The aim of this study was to examine if prior urine cultures can predict antibiotic susceptibility profile in a subsequent culture, in children with recurrent urinary tract infections. The medical records of all children with at least two episodes of urinary tract infection between 1999-2015 that occurred 2 weeks to 1 year apart were reviewed. Pathogen identity and antibiogram were compared between the two cultures for every patient. One hundred sixty-one cases of recurrent urinary tract infections were identified. Seventy-seven (48%) pairs of cultures grew the same pathogen. However, of these, 31 had an altered biogram. In 53% of the culture pairs, the pathogen in the second culture had a similar or better antibiotic susceptibility profile. We found no statistically significant correlation between the elapsed time between the two cultures and the probability of similar susceptibility profile between them. There was no correlation between antibiogram change and any of the demographic characteristics, including a history of renal transplantation and taking antibiotic prophylactic treatment.Conclusions: Antibiotic susceptibility profile of the pathogen in a prior urinary tract infection did not predict antibiotic susceptibility profile in a subsequent urinary tract infection in our study.What is Known:• Children with urinary tract infections often have recurrent infections.• Clinicians often use prior urine cultures to choose empirical antibiotic treatment in subsequent infections.What is New:• In only 50% of the cases, a subsequent urinary tract infection grows the same pathogen as the 1st urinary tract infection.• Even in cultures with the same pathogen growth, antibiogram is often different.