Abstract
Background
Double J ureteral stents are widely used on urological patients to provide drainage of the upper urinary tract. Unfourtunately, ureteral stents are not free from complications, as bacterial colonization and require a second procedure for removal. The purpose of the current comparative experimental study is to evaluate a new heparin-coated biodegradable antireflux ureteral stent (BraidStent®-H) to prevent urinary bacterial colonization.
Methods
A total of 24 female pigs were underwent determination of bacteriuria and nephrosonographic, endoscopic and contrast fluoroscopy assessment of the urinary tract. Afterward, were randomly assigned animals to Group-I, in which a 5Fr double-pigtail ureteral stent was placed for 6 weeks, or Group-II, in which a BraidStent®-H was placed. Follow-up assessments were performed at 1, 3, 6, 8, 12 weeks. The final follow-up includes the above methods and an exhaustive pathological study of the urinary tract was accomplished after 20 weeks.
Results
Bacteriuria findings in the first 48 h were significant between groups at 6 h and 12 h. Asymptomatic bacteriuria does not reach 100% of the animals in Group-II until 48 h versus Group-I where it appears at 6 h. The weekly bacteriuria mean rate was 27.7% and 44.4% in Group I and II respectively, without statistical significance. In Group II there were no animals with vesicoureteral reflux, with statistical significance at 3 and 6 weeks with Group-I. The 91.2% of stents in Group-II were degraded between 3 and 6 weeks, without obstructive fragments. Distal ureteral peristalsis was maintained in 66.6–75% in Group-II at 1–6 weeks.
Conclusions
The heparin coating of BraidStent® allows an early decrease of bacterial colonization, but its effectiveness is low at the long term. Heparin coating did not affect scheduled degradation rate or size of stents fragments. BraidStent®-H avoids the side effects associated with current ureteral stents, thus should cause less discomfort to patients.
Heparin coating in biodegradable ureteral stents does not decrease bacterial colonization—assessment in ureteral stricture endourological treatment in animal model
