Abstract: TH-PO653

Identification of Novel Urinary Proteins to Distinguish Urinary Tract Infection from Colonization in Catheterization-Dependent Children

Session Information

  • Pediatric Nephrology
    November 02, 2017 | Location: Hall H, Morial Convention Center
    Abstract Time: 10:00 AM - 10:00 AM

Category: Developmental Biology and Inherited Kidney Diseases

  • 403 Pediatric Nephrology

Authors

  • Forster, Catherine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
  • Goldstein, Stuart, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States
  • Greis, Ken, University of Cincinnati, Cincinnati, Ohio, United States
  • Devarajan, Prasad, Cincinnati Children's Hospital, Cincinnati, Ohio, United States
Background

Children with neurogenic bladders who require clean intermittent catheterization (CIC) often have bacteriuria. Distinguishing urinary tract infection (UTI) from urinary tract colonization (UTC) is difficult. Our objective was to identify urinary proteins to distinguish UTI from UTC in CIC-dependent children.

Methods

10 CIC-dependent children were included (UTI=5, UTC=5). UTI was defined as: 1) > 50,000 cfu/ mL of a uropathogen, 2) > 10 urinary white blood cells, and 3) >2 of the following: fever, abdominal or back pain, worsened incontinence, pain with CIC, or cloudy or malodorous urine. UTC was defined as a bacteriuria in an asymptomatic patient. Medical records of patients who met UTI criteria were reviewed to select those with clear UTI symptomatology. 5 UTC patients were matched on age and uropathogen. Quantitative profiling of urine proteins with isobaric protein labeling was performed using tandem mass spectrometry. Candidate markers were normalized using a collective mixture of proteins from all samples. Relative quantitative abundance of proteins across all samples were compared. Proteins with a significant fold-change across either UTI or UTC, with >50% change in the average abundance across groups were identified as proteins of interest.

Results

Eight proteins were differentially expressed. These included: haptoglobin and liver fatty-acid binding protein (LFABP) overexpressed in UTI; and apolipoprotein D, α-amylase 2B, inter-α-trypsin inhibitor heavy chain H4, non-secretory ribonuclease, CD44 antigen, and prosaposin overexpressed in UTC. Protein functions include antimicrobial activity (haptoglobin), inflammation (LFABP, apolipoprotein D, inter-α-trypsin inhibitor heavy chain H4, non-secretory ribonuclease, prosaposin, and CD44 antigen), and metal binding (α-amylase 2B).

Conclusion

These urinary proteins have potential to distinguish UTI from UTC in CIC-dependent children.