AUA 2017: Stent Early Encrustation (See) Study: Factors Associated With Acute Calcifications

Boston, MA (UroToday.com) Dr. William T. Berg, from Stony Brook University, presented data that identified risk factors associated with acute ureteral stent encrustation. As an introduction to his presentation, Dr. Berg explained that many previous research studies have focused on the development of different of biomaterials, coatings, etc. as solutions to decrease stent encrustation. However, these past studies have focused on in vitro models and to date no detailed clinical data exists on patient characteristics of stent early encrustation.

For this prospective study, patients with indwelling ureteral stent were screened and tested for ureteral stent early encrustation. Patient information such as medical history, indwelling stent time, and stent size were collected. For these patients at the time of stent removal, urine analysis, urine culture, stent culture, and stone analysis were performed.

Following screening and testing, 12 patients were found to have early stent encrustation. These patients had a mean stent dwell time of 48 days, 42% had positive urine culture, and 58% had positive stone and stent culture. Interestingly, of the patient cultures with positive stone and stent cultures, none were shown to have the same organism isolated in the culture. However, these organisms were dissimilar from organisms isolated from urine. Additionally, after stone analysis it was found that for this study the most common calcification for patients with early stent encrustation was Brushite (42%) followed by calcium phosphate (30%), calcium oxalate (18%), and struvite (11%).

Dr. Berg concluded by recommending that for patients with stent early encrustation, separate stone and calcified stent cultures should be obtained. This is especially important in patients requiring stent exchange or other additional procedures.

Presented by: William T. Berg, MD, Department of Urology, Stony Brook, NY

Authors: William T. Berg, Yefim Sheynkin, David Schulsinger

Affiliation: Department of Urology, Stony Brook, NY

Written By: Renai Yoon, Department of Urology, University of California, Irvine

at the 2017 AUA Annual Meeting - May 12 - 16, 2017 – Boston, Massachusetts, USA