Bacterial colonization of ureteral stents

Objectives: The aim of this study was to assess the frequency of bacterial stent colonization and stent-associated bacteriuria, and to evaluate the si gnificance of urinary cultures for identification of colonizing microorgani sms. Methods: A total of 93 ureteral stents from 71 patients were examined: 9 patients with permanent ureteral stenting due to malignant ureteral obst ruction (27 stents), and 62 patients with temporary ureteral stents (66 ste nts). Results: Bacteriuria and bacterial stent colonization were found in a ll patients with permanent stents. In patients with temporary stents, colon ized stents were found in 69.3% (43/62), mainly in combination with sterile urine (45.2%, 28/62), Mean indwelling times did not differ between patient s with sterile urine and sterile stents (11.8 days) and patients with steri le urine and colonized stents (11.2 days). Prophylactic antibiosis in 42/62 temporarily stented patients did not reduce colonization rates compared to patients without antibiotics (70 vs. 65%). Enterococci were the bacteria m ost frequently cultured from urine and stents. Conclusions: In the present study, ureteral stent colonization rates were 100% in permanently and 69.3% in temporarily stented patients. Antibiotic prophylaxis did not prevent st ent colonization and should not be routinely ad-ministered. Since urinary c ultures correctly identified all colonizing microorganisms in only 21%, rem oval/replacement and bacteriologic evaluation of ureteral stents may be nec essary in case of urosepsis.