ACS 2018: Profiling the Urinary and Gastrointestinal Microbiota in Male Children Presenting to Urology with or Without Prior Exposure

Boston, Massachusetts ( Borna Kassiri, a medical student from Johns Hopkins School of Medicine, presented preliminary work characterizing the urinary microbiome in a pediatric population. They hypothesized that the urinary microbiota begin colonizing the urinary tract in childhood. They aimed to 1) begin to assess the microbial composition of urine and stool from infants through young adults and 2) compare the urinary and gastrointestinal (GI) microbiome in children with or without antibiotic exposure.

They collected urine via transurethral catheterization and fecal samples via rectal swab from pediatric patients. They extracted DNA from the samples of 20 male patients presenting to urology at Johns Hopkins Hospital (ages 3 months - 8 years; median age 15 months). The sample set consists of 10 fecal and 5 urine samples from 10 patients without antibiotic exposure and from 10 age-matched patients with antibiotic exposure. The samples underwent 16S ribosomal DNA Illumina amplicon sequencing to characterize the GI and urinary microbiota in these two groups.

They found evidence of a urinary microbiome in pediatric males, with a similar composition to that previously described in adult men. Urine bacterial load was similar to levels found in adult men. Urinary and GI microbial diversity of patients with antibiotic exposure did not differ significantly from the urinary and GI microbial diversity of patients without antibiotic exposure (p=0.382 and p=0.927, respectively).

In conclusion, while these data support the existence of a urinary microbiome in pediatric males, future studies are warranted to elucidate the pediatric GI and urinary microbiota and to establish long-term effects of antibiotic prophylaxis in the pediatric population. Moreover, there is mounting evidence of sex differences in urinary microbiome which warrants further investigation according to sex. These data have important implications which stretch beyond infection and into cancer care as well considering immunology and microbiome interactions.

Presented by: Borna Kassiri, Medical Student, Johns Hopkins School of Medicine 

Written by: Stephen B. Williams, MD., Associate Professor, Division of Urology, The University of Texas Medical Branch, Galveston, TX. and Ashish M. Kamat, MD. Professor, Department of Urology, Division of Surgery, The University of Texas MD Anderson Cancer Center, Houston, TX at the 2018 American College of Surgeons Clinical Congress, October 21-25, 2018 in Boston, Massachusetts