Infective complications associated with ureteral stents in renal transplant recipients

Detection of microbial biofilms inside the lumen of ureteral stents: two case reports

BACKGROUND

We report large biofilm structures that covered almost the entirety of the lumen and surface of double-J stents in two postrenal transplant patients, with no development of urinary tract infection. Biofilm bacteria of one patient were integrated by coccus in a net structure, whereas overlapping cells of bacilli were present in the other patient. To the best of our knowledge, this is the first time that high-quality images of the architecture of noncrystalline biofilms have been found inside double-J stents from long-term stenting in renal transplant recipients.

CASE PRESENTATION

Two renal transplant recipients, a 34-year-old male and a 39-year-old female of Mexican-Mestizo origin, who underwent a first renal transplant and lost it due to allograft failure, had a second transplant. Two months after the surgical procedure, double-J stents were removed and analyzed using scanning electron microscopy (SEM). None of the patients had an antecedent of UTI, and none developed UTI after urinary device removal. There were no reports of injuries, encrustation, or discomfort caused by these devices.

CONCLUSION

The bacterial biofilm inside the J stent from long-term stenting in renal transplant recipients was mainly concentrated on unique bacteria. Biofilm structures from the outside and inside of stents do not have crystalline phases. Internal biofilms may represent a high number of bacteria in the double-J stent, in the absence of crystals.

Bacterial Colonization in Double J Stent and Bacteriuria in Post-Renal Transplant Patients

Background and objective

Urinary tract infections (UTI) in kidney transplant recipients can cause significant morbidity and negatively impact both, graft and patient survival. Ureteric stenting in renal transplantation is aimed at reducing the risks of complications like ureteric leak and stenosis. Ureteric stents are not without their potential complications which may include UTI. We aimed to compare urine bacteriology and bacterial colonization of DJ stent following kidney transplantation, and to establish antimicrobial susceptibility to guide the choice of empirical antibiotics in the event of UTI in post-transplant patients with DJ stent.

Materials and methods

This was a prospective study carried out over a year period (February 2020 to January 2021). Eighty post-renal transplant patients with indwelling ureteral stents were recruited for the study. An early morning midstream urine sample was taken for analysis from consenting patients that met the inclusion criteria. All stents were removed via rigid cystoscopy and the distal end of the stent (4cm) was cut off and put in a sterile bottle for microbiological analysis. Sensitivity and resistance were tested against a panel of 19 antibiotics on all microbial isolates. Results were considered statistically significant when p < 0.05.

Results

The mean age of the patients was 47.9+ 12.1 years. Male patients were 60 (75%) while 20 (25%) were females. Fifty-one (52%) patients had hypertension while 25 (26%) had diabetes mellitus. Hypertension and diabetes were noted in 20 (21%) patients while only one patient (1%) had HCV. Prior to renal transplantation, patients had negative urine cultures. The majority of the patients (76, 95%) had their stent retrieved after 4 weeks, 2 (2.5%) of them had stents retrieved after 2 weeks, and 2 (2.5%) had stents retrieved after 8 weeks. There was a significant association between the duration of stent and stent colonization (p=0.031).

No organism was cultured in both the urine and stent in 13 (14.4%) patients. Nine (10%) had positive stent culture with a negative urine culture while 5 (5.6%) had positive urine culture with a negative stent culture. The same organism was noted in both urine and stent in 58 (64.4%) of patients while different organisms were cultured in 5 (5.6%) of the patients. Escherichia coli was the most common organism cultured in the urine of 38 (65.5%) patients and 36 (58.1%) stents, respectively.

The sensitivity pattern shows that the organisms were more susceptible to nitrofurantoin and gentamicin, and resistant to tetracycline and ceftriaxone. Tigecycline showed good susceptibility and poor resistance.

Conclusion

This study shows that stent colonization was slightly higher than urine bacteriology, with both demonstrating similar microbiological patterns. Selection of the initial empiric treatment should be based on local epidemiological data. Initial therapy should be de-escalated to the most narrow-spectrum antibiotics to complete the course of therapy once culture and sensitivity data is available. Antibiotics stewardship will help in reducing the trend of MDR pathogens.

Urinary Tract Infections in the First 6 Months after Renal Transplantation

Purpose

Urinary tract infections (UTIs) are common in the first 6 months after renal transplantation, and there are only limited data about UTIs after transplantation in Saudi Arabia in general.

Methods

A retrospective study from January 2017 to May 2020 with 6-month follow-up.

Results

279 renal transplant recipients were included. Mean age was 43.4 ± 16.0 years, and114 (40.9%) were women. Urinary stents were inserted routinely during transplantation and were removed 35.3 ± 28 days postoperatively. Ninety-seven patients (35%) developed urinary tract infections (UTIs) in the first six months after renal transplantation. Of those who developed the first episode of UTI, the recurrence rates were 57%, 27%, and 14% for having one, two, or three recurrences, respectively. Late urinary stent removals, defined as more than 21 days postoperatively, tended to have more UTIs (OR: 1.43, P: 0.259, CI: 0.76–2.66). Age >40, female gender, history of neurogenic bladder, and transplantation abroad were statistically significant factors associated with UTIs and recurrence. Diabetes, level of immunosuppression, deceased donor renal transplantation, pretransplant residual urine volume, or history of vesicoureteral reflux (VUR) was not associated with a higher incidence of UTIs. UTIs were asymptomatic in 60% but complicated with bacteremia in 6% of the cases. Multidrug resistant organisms (MDROs) were the causative organisms in 42% of cases, and in-hospital treatment was required in about 50% of cases. Norfloxacin + Bactrim DD (160/800 mg) every other day was not associated with the lower risk of developing UTIs compared to the standard prophylaxis daily Bactrim SS (80/400 mg).

Conclusion

UTIs and recurrence are common in the first 6 months after renal transplantation. Age >40, female gender, neurogenic bladder, and transplantation abroad are associated with the increased risk of UTIs and recurrence. MDROs are common causative organisms, and hospitalization is frequently required. Dual prophylactic antibiotics did not seem to be advantageous over the standard daily Bactrim.

Risk factors in bacterial colonization of internal ureteral stent

A ureteral stent is most broadly used to manage upper urinary tract disorders such as obstruction and prevent post-endoscopic complications. However, the stent may become a niche for bacterial colonization. This study aimed to determine the rate of bacterial colonization and type of bacteria in internal ureteral stents and the risk factors associated with bacterial colonization. This prospective cross-sectional study included 100 consecutive adult patients who had temporary ureteral stenting as preparation for a secondary ureterorenoscopy at Al-Yarmook Hospital/ Baghdad. All included patients were negative for bacterial culture before stenting. Stent and urine culture were performed at the time of stent removal. The colonization rate and bacteriuria in patients with internal ureteral stent were 19% and 9%, respectively. The most common bacteria in-stent and urine were E. coli accounting for 31.58% and 33.33%. Pseudomonas aeruginosa was common in stent culture, representing 21.05%. Positive bacterial culture was confirmed in 19 stents and 9 urine samples. All cases with positive urine samples were also positive for culture. Thus, the sensitivity and specificity of urine culture for detection of stent colonization were 47.37% and 100%, respectively. Diabetes mellitus, chronic renal failure, and prolonged stenting were significantly associated with increased stent colonization. The ureteral stent could be a source of urinary tract infection. The most pathogenic bacteria associated with the ureter stent are E. coli and Pseudomonas aeruginosa. Risk factors associated with stent colonization are diabetes mellitus, chronic renal failure, and prolonged indwelling time.

Association Between the Placement of a Double-J Catheter and the Risk of Urinary Tract Infection in Renal Transplantation Recipients: A Retrospective Cohort Study of 1038 Patients

BACKGROUND

The incidence of urinary complications in transplantation is 2% to 20%, which can be decreased with the use of a double-J catheter. The objective of this study was to determine the association between the use of the catheter and the probability of urinary tract infection (UTI).

METHODS

We studied a retrospective cohort of 1038 patients divided into 2 groups: those treated with vs without a double-J catheter. Perioperative factors related to catheter use were analyzed. Second, whether the use of the catheter was associated with fewer other urinary complications was analyzed.

RESULTS

Of the whole sample, 72 patients were eliminated from the study, and 358 (37%) received a double-J catheter. UTIs occurred in 190 patients (19.6%), of whom a greater proportion received a catheter: 88 of 358 (24.6%) vs 102 of 608 (16.8%) (odds ratio, 1.61; 95% confidence interval, 1.17-2.22; P = .003).

CONCLUSIONS

The placement of a double-J catheter during transplant is associated with a higher proportion of UTIs, increasing their severity and the cost of care, without having a clear effect on other types of urinary complications.

The Impact of Timing of Stent Removal on the Incidence of UTI, Recurrence, Symptomatology, Resistance, and Hospitalization in Renal Transplant Recipients

Purpose

To evaluate the impact of early (<3 weeks) versus late (>3 weeks) urinary stent removal on urinary tract infections (UTIs) post renal transplantation.

Methods

A retrospective study was performed including all adult renal transplants who were transplanted between January 2017 and May 2020 with a minimum of 6-month follow-up at King Abdulaziz Medical City, Riyadh, Saudi Arabia.

Results

A total of 279 kidney recipients included in the study were stratified into 114 in the early stent removal group (ESR) and 165 in the late stent removal group (LSR). Mean age was 43.4 ± 15.8; women: n: 114, 40.90%; and deceased donor transplant: n: 55, 19.70%. Mean stent removal time was 35.3 ± 28.0 days posttransplant (14.1 ± 4.6 days in the ESR versus 49.9 ± 28.1 days in LSR, p < 0.001). Seventy-four UTIs were diagnosed while the stents were in vivo or up to two weeks after the stent removal “UTIs related to the stent” (n = 20, 17.5% in ESR versus n = 54, 32.7% in LSR; p=0.006). By six months after transplantation, there were 97 UTIs (n = 36, 31.6% UTIs in ESR versus n = 61, 37% in LSR; p=0.373). Compared with UTIs diagnosed after stent removal, UTIs diagnosed while the stent was still in vivo tended to be complicated (17.9% versus 4.9%, p: 0.019), recurrent (66.1% versus 46.3%; p: 0.063), associated with bacteremia (10.7% versus 0%; p: 0.019), and requiring hospitalization (61% versus 24%, p: 0.024). Early stent removal decreased the need for expedited stent removal due to UTI reasons (rate of UTIs before stent removal) (n = 11, 9% in the early group versus n = 45, 27% in the late group; p=0.001). The effect on the rate of multidrug-resistant organisms (MDRO) was less clear (33% versus 47%, p: 0.205). Early stent removal was associated with a statistically significant reduction in the incidence of UTIs related to the stent (HR = 0.505, 95% CI: 0.302-0.844, p=0.009) without increasing the incidence of urological complications. Removing the stent before 21 days posttransplantation decreased UTIs related to stent (aOR: 0.403, CI: 0.218-0.744). Removing the stent before 14 days may even further decrease the risk of UTIs (aOR: 0.311, CI: 0.035- 2.726).

Conclusion

Early ureteric stent removal defined as less than 21 days post renal transplantation reduced the incidence of UTIs related to stent without increasing the incidence of urological complications. UTIs occurring while the ureteric stent still in vivo were notably associated with bacteremia and hospitalization. A randomized trial will be required to further determine the best timing for stent removal.

Minimal-invasive management of urological complications after kidney transplantation

Kidney transplantation represents the gold standard treatment option for patients with end-stage renal disease. Improvements in surgical technique and pharmacologic treatment have continuously prolonged allograft survival in recent years. However, urological complications are frequently observed, leading to both postoperative morbidity and putative deterioration of allograft function. While open redo surgery in these patients is often accompanied by elevated surgical risk, endoscopic management of urological complications is an alternative, minimal-invasive option. In the present article, we reviewed the literature on relevant urological postoperative complications after kidney transplantation and describe preventive approaches during the pre-transplantation assessment and their management using minimal-invasive approaches.

The Ureter in the Kidney Transplant Setting: Ureteroneocystostomy Surgical Options, Double-J Stent Considerations and Management of Related Complications

Purpose of Review

In the setting of kidney transplantation, the ureter is a common source for complications. As a result, prevention of ureteral complications and their management is of crucial importance. In this context, the purpose of this review is to summarize recent literature on the ureter in the kidney transplant setting with a special focus on new findings. We conducted a PubMed and Medline search over the last 10 years to identify all new publications related to ureteroneoimplantations, stents and management of complications in the kidney transplant setting.

Recent Findings

Performance of the “Lich-Gregoir” technique for ureteroneocystostomy seems to be favourable in regard to postoperative complications when compared with other methods described in the literature. Moreover, major urologic complications can be further reduced by ureteral stenting.

Summary

A new approach for management of ureteral strictures in renal transplants is presented. We discussed the usage of a ureteral stent covered with a biostable polymer aiming to prevent tissue ingrowth into the lumen as a new option for management of ureteral stricture in the kidney transplant setting.

Timing of Ureteric Stent Removal and Occurrence of Urological Complications after Kidney Transplantation: A Systematic Review and Meta-Analysis

Implanting a ureteric stent during ureteroneocystostomy reduces the risk of leakage and ureteral stenosis after kidney transplantation (KTx), but it may also predispose to urinary tract infections (UTIs). The aim of this study is to determine the optimal timing for ureteric stent removal after KTx. Searches were performed in EMBASE, MEDLINE Ovid, Cochrane CENTRAL, Web of Science, and Google Scholar (until November 2017). For this systematic review, all aspects of the Cochrane Handbook for Interventional Systematic Reviews were followed and it was written based on the PRISMA-statement. Articles discussing JJ-stents (double-J stents) and their time of removal in relation to outcomes, UTIs, urinary leakage, ureteral stenosis or reintervention were included. One-thousand-and-forty-three articles were identified, of which fourteen articles (three randomised controlled trials, nine retrospective cohort studies, and two prospective cohort studies) were included (describing in total n = 3612 patients). Meta-analysis using random effect models showed a significant reduction of UTIs when stents were removed earlier than three weeks (OR 0.49, CI 95%, 0.33 to 0.75, p = 0.0009). Regarding incidence of urinary leakage, there was no significant difference between early (<3 weeks) and late stent removal (>3 weeks) (OR 0.60, CI 95%, 0.29 to 1.23, p = 0.16). Based on our results, earlier stent removal (<3 weeks) was associated with a decreased incidence of UTIs and did not show a higher incidence of urinary leakage compared to later removal (>3 weeks). We recommend that the routine removal of ureteric stents implanted during KTx should be performed around three weeks post-operatively.

Does early removal of double J stents reduce urinary infection in living donor renal transplantation?

INTRODUCTION

Prophylactic use of double J (DJ) stents in recipients is highly accepted in renal transplantation. In this study, the association between the frequency of urologic complications (UC) and urinary tract infections (UTI), and the early or late removal of DJ stents was investigated.

MATERIAL AND METHODS

A total of 116 live-donor renal transplant patients were included in the study during a 4-year period, with a mean follow-up of 29.2 ±15.3 months. In all, DJ stents were used. All patients were clinically monitored for graft function by assessment of the complete blood count, renal biochemistry, urine analysis and blood drug level according to our follow-up protocol.

RESULTS

The patients were divided into 2 groups according to the time of their stent removal: group I (n = 44), removal within the first 14 days; and group II (n = 72), removal after 14 days. No urinary leaks were detected in either of the groups. Three patients suffered from anastomotic stricture (group I, n = 1; group II, n = 2). The rates of UTI were similar in groups I and II (13.6% vs. 16.6%, respectively, p = 0.79). The rate of UTI in women was found to be 3.8 times higher than in men.

CONCLUSIONS

The results of our study demonstrated that DJ stent removal within 14 days did not reduce the risk of UTI when compared to stent removal after 14 days. Similar effects on complication rates for ureteral stenting for these 2 removal periods were observed.

Solid organ transplantation in older adults. Infectious and other age-related considerations

In the U.S., older adults aged 65 or above comprise nearly one quarter of the solid organ transplant (SOT) waitlists, and the number of transplants performed in this age group continues to increase. There are no specific guidelines for the assessment and follow up of the older SOT candidate or recipient. Older adults are at increased risk of infectious complications after SOT. Despite these complications and even with the use of suboptimal donors, overall outcomes are favorable. We provide an overview to specific consideration as they relate to the older SOT candidate and recipient.

Association of Double-J Stenting in Renal Transplant Patients With Urinary Tract Colonization and Infections in a Multidrug-resistant Microbe Endemic Nosocomial Environment

PURPOSE

We investigated the association of ureteral stenting after kidney transplantation with the development of urinary tract infections (UTIs) and/or urinary tract colonization, in a hospital environment considered endemic for multidrug resistant (MDR) Gram-negative Enterobacteriaceae.

METHODS

Seventy-five recipients of deceased donor grafts were divided in groups A and B. Group A (with subgroups A1 and A2) included 45 transplanted patients without urinary stenting, and group B 30 patients with stenting. Subgroup A1 consisted of 30 patients transplanted before 2006, and A2 of 15 patients transplanted after 2006, when MDR, mainly carbapenem-resistant, Enterobacteriaceae, frequency has risen in our hospital.

RESULTS

The incidence and the number of UTIs per patient were significantly higher in patients without stenting compared to those with stenting. (Group A: 32/45 vs group B: 9/30, P < .001, and group A: 2.86 ± 0.43 vs group B: 0.6 ± 0.19, P < .01 respectively). Patients without stenting tended to have a higher frequency of recurrent UTIs compared to those with stenting (group A: 16/45 vs group B: 4/30, P < .05). Asymptomatic bacteriuria was more frequent in the patients with stent (group A: 8/45 vs group B: 14/30, P < .05). Further sub-comparison of the A1 and A2 subgroups with group B did not change the statistical results.

CONCLUSIONS

There is no clinically significant association of ureteral stenting after kidney transplantation with the high frequency of MDR Gram-negative bacteria in our hospital.

To Stent or Not To Stent, That Is the Question

With the increasing complexity of donor organs, recipients, training, and departmental standardisation, routine ureteric stent placement should be advocated. Transplant centres should consider utilising novel technologies for transplant stent removal for a simpler, cheaper procedure that can be performed in any outpatient department.

Early Versus Delayed Double J Stent Removal in Deceased Donor Renal Transplant Recipients: A Prospective Comparative Study

Introduction: Prophylactic ureteric stents have been commonly employed to reduce the incidence of ureteric obstruction and anastomotic leaks following renal transplantation. There are very few studies on the duration of ureteric stenting in deceased donor renal transplantation (DDRT). We performed a prospective study to compare early and late double J stent removal in DDRT.

Aims and methods: The aim of this study was to compare the early and delayed removal of ureteric stents after DDRT. We performed 80 DDRTs at our center from August 2012 to December 2016, which were included in the study. However, we enrolled 48 patients as the remaining had to be excluded based on the high-risk factors. The recipients were allocated on the 14th postoperative day to two groups. Group 1 underwent early stent removal on the fourteenth postoperative day and in group 2, the stent was removed in the sixth postoperative week. The two groups were followed up for six months and the incidence of urological complications and urinary tract infections (UTI) was compared.

Results: The incidence of UTI during the follow-up period of six months was significantly lower in the early stent removal group (two out of 24) than in delayed stent removal group (eight out of 24) (p=0.016). Asymptomatic bacteriuria occurred in six out of 24 (25%) in group 1 and 10 out of 24 (41.6%) in group 2 (p=0.120). There was no significant difference in the incidence of urinary leak, hematuria, or ureteric obstruction between the two groups (p=0.900). However, stent-related symptoms were significantly more in the delayed stent removal group (three in group 1 versus 18 in group 2) (p=0.001).

Conclusion: Prolonged stenting is associated with an increased risk of UTI and stent-related symptoms in immunosuppressed renal transplant recipients. The early removal of double J stents can be done in carefully selected patients to reduce stent-related complications in DDRT.

A survey of Canadian renal transplant surgeons: Use of ureteric stents and technique of the ureteroneocystotomy

INTRODUCTION

The role of ureteric stenting in renal transplant has been well-demonstrated. The goal of this survey was to determine the utilization of ureteric stents by Canadian transplant surgeons, and how the ureteroneocystotomy and followup is performed.

METHODS

An online survey was sent to the 40 surgeon members of the Canadian Society of Transplantation. The primary outcome was the rate of ureteric stent use at the time of renal transplantation. The secondary outcomes were the ureteric stent dwell time, use and type of prophylactic antibiotics, and the use of routine post-transplant ultrasonography.

RESULTS

All respondents (25) used ureteric stent routinely and 92% remove the stent between four and six weeks postoperatively. Prophylactic antibiotics were used 64% of the time for ureteric stent removal. The majority of surgeons do not routinely perform a post-stent removal ultrasound. Fifty-six percent of respondents perform a refluxing anastomosis.

CONCLUSIONS

Ureteric stents are routinely used in renal transplant in Canada. Areas for improvement and topics of debate identified from this survey are the need for peri-stent removal antibiotics, the role of post-stent removal ultrasound, the duration of stent dwell time, and the need for a non-refluxing ureteroneocystotomy.

Optimal Timing for Removal of the Double-J Stent After Kidney Transplantation

BACKGROUND

Urologic complications (UC) have gradually decreased in recent years after advanced surgical experience. The incidence of urologic complications varies between 0.22% and 30% in different medical studies. There is no routine usage of double-J stenting (DJS) during renal transplantation (RT) in the literature. It is a necessity, and optimal timing for stent removal is an important question for many transplantation centers.

METHODS

This study includes 818 renal transplant patients whose ureteroneocystostomy anastomoses were completed by use of the Lich-Gregorie procedure during a 2-year period at a transplantation center. We performed 926 renal transplantations at Antalya Medical Park Hospital Renal Transplantation Center between January 2014 and January 2016. The patients were divided into four groups according to the timing of DJS removal.

RESULTS

For group 1, removal time for DJS was between 5 and 7 days; group 2, Removal time for DJS was between 8 and 14 days; group 3, removal time for DJS was between 15 and 21 days; and group 4, removal time for DJS was later than 22 days. The patients were divided into two groups according to removal time of stent as 5 to 14 days and >15 days. DJS was performed again in the patients whose urine output was reduced during the first 5 days after removal of the DJS, whose creatine level increased, and whose graft ureter and collecting tubules were extended as an ultrasonographic finding.

CONCLUSIONS

There is no declared optimal time for the removal of DJS. The removal time was reported between postoperative first week and 3 months in some of the reports of RT centers, according to their protocols. We emphasize that the optimal time for the removal of DJS is 14 to 21 days after RT, based on the findings of our large case report study.

Minimizing the Number of Urological Complications After Kidney Transplant: A Comparative Study of Two Types of External Ureteral Stents

OBJECTIVES

The aim of this study was to evaluate the effects of 2 types of external ureteral stents on the number of urological complications after kidney transplant.

MATERIALS AND METHODS

Data were retrospectively collected from 366 consecutive transplants performed between January 2013 and January 2015 in our hospital, in which an external ureteral stent was placed during surgery and removed after 9 days. Urological complications were defined as urinary leakage or ureteral stenosis requiring percutaneous nephrostomy placement.

RESULTS

A total of 197 patients received a straight stent with 2 larger side holes (type A; 8F "Covidien" tube; Covidien, Dublin, Ireland) and 169 patients received a single J stent with 7 smaller side holes (type B; 7F "Teleflex" single J stent; Teleflex Medical, Athlone, Ireland). We found a significantly higher number of percutaneous nephrostomy placements with type A stents, with 34 (17%) versus 16 (9%) in type B (P = .030). Reason for percutaneous nephrostomy placement, occurrence of stent dysfunction, and need for early removal (< 8 days) were equal in both groups (P = .397), whereas incidence of rejection and urinary tract infection were higher in type B stent group. Patient and graft survival did not differ between the groups.

CONCLUSIONS

Use of the type B stent was associated with less urological complications compared with the type A stent.

Double-J Versus External Ureteral Stents in Kidney Transplantation: A Retrospective Analysis

Background:

Kidney transplantation has long been recognized as the best available therapy for end stage kidney disease.

Objectives:

This study aimed to compare outcomes of double-J versus percutaneous ureteral stent placement in renal transplantation.

Patients and Methods:

A retrospective analysis was performed on data of renal transplantations performed at our institution in a 12-month period. In this period, external and double-J stents were used in parallel. Length of hospital stay and stent-associated complications were evaluated.

Results:

In 76 kidney transplants, 43 external (group 1) and 33 double-J (group 2) urinary stents were used. No significant difference was observed in the number of urinary tract infections, ureteric stenosis or necrosis. The mean overall length of hospital stay was comparable in both groups (20.7 days in group 1 vs 19.3 days in group 2, P = 0.533). For patients without immunological complications, the hospital stay was significantly reduced using double-J stents (12.9 days in group 1, 10.8 days in group 2, P = 0.018). Leakage of the ureteroneocystostomy occurred in 6 out of 43 patients in group 1 (13.9%). No case of anastomotic insufficiency was observed in group 2 (P = 0.035). Macrohematuria was detected in 13 out of the 43 patients in group 1 (30.2%), compared to 3 out of 33 patients in group 2 (9.1%; P = 0.045).

Conclusions:

This nonrandomized comparison of stent types in kidney transplantation supports the use of prophylactic double-J stents in terms of decreased ureteric complications and reduced length of hospital stay.

Extended-spectrum-beta-lactamase producing bacteria related urinary tract infection in renal transplant recipients and effect on allograft function

Background

Urinary tract infection (UTI) is a well-recognized early complication in renal transplant recipients (RTR) and can have significant bearing on their outcome. The recent rise in incidence of extended spectrum beta lactamase (ESBL) producing bacteria causing UTI among RTR poses new and significant challenges in terms of management and outcome. Our aim is to analyze the effect of ESBL producing bacteria causing UTI in these patients and its impact on allograft function.

Methods

We reviewed the medical records of 147 RTR who were followed at a tertiary care hospital affiliated transplant center between January 2007 and May 2013 and noted five RTR who developed episodes of ESBL producing bacteria related UTI during follow up. Multiple patient characteristics including demographics, immunosuppression, recurrences, allograft function and outcome were analyzed.

Results

Five patients (3.4%) out of 147 had ESBL producing bacteria related UTI. We found all patients to be above 60 years of age, with three out of five being females, and all five patients had diabetes mellitus. We identified a total of 37 episodes of UTI among these five patients during this period. Two of these patients had elevated creatinine values during the episodes of UTI and three of them developed bacteremia. Of the five patients, four of them had a favorable outcome except for one patient who developed persistent allograft dysfunction.

Conclusion

RTR are at a higher risk for developing ESBL producing bacteria associated UTI. Early diagnosis along with appropriate and judicious use of antibiotics will ensure long term success in allograft and patient outcome.

Effect of ureteric stents on urological infection and graft function following renal transplantation

AIM: To compare urological infections in patients with or without stents following transplantation and to determine the effect of such infections on graft function.

METHODS: All 285 recipients of kidney transplantation at our centre between 2006 and 2010 were included in the study. Detailed information including stent use and transplant function was collected prospectively and analysed retrospectively. The diagnosis of urinary tract infection was made on the basis of compatible symptoms supported by urinalysis and/or microbiological culture. Graft function, estimated glomerular filtration rate and creatinine at 6 mo and 12 mo, immediate graft function and infection rates were compared between those with a stent or without a stent.

RESULTS: Overall, 196 (183 during initial procedure, 13 at reoperation) patients were stented following transplantation. The overall urine leak rate was 4.3% (12/277) with no difference between those with or without stents - 7/183 vs 5/102, P = 0.746. Overall, 54% (99/183) of stented patients developed a urological infection compared to 38.1% (32/84) of those without stents (P = 0.0151). All 18 major urological infections occurred in those with stents. The use of stent (Wald χ² = 5.505, P = 0.019) and diabetes mellitus (Wald χ² = 5.197, P = 0.023) were found to have significant influence on urological infection rates on multivariate analysis. There were no deaths or graft losses due to infection. Stenting was associated with poorer transplant function at 12 mo.

CONCLUSION: Stents increase the risks of urological infections and have a detrimental effect on early to medium term renal transplant function.

Is early removal of prophylactic ureteric stents beneficial in live donor renal transplantation?

Prophylactic ureteric stenting has been shown to reduce ureteric leaks and collecting system obstruction following renal transplantation and is in widespread use. However, the optimal time for removal of ureteric stents after renal transplantation remains unclear. Aim of this study was to compare the result of early versus late removal of ureteric stents after kidney transplantation of the laparoscopically retrieved live related donor grafts. Eligible patients were live donor kidney transplant recipients with normal urinary tracts. All recipients underwent extravesical Lich-Gregoire ureteroneocystostomy over 4F/160 cm polyurethane double J stents by a uniform technique. They were randomized on seventh postoperative day for early removal of stents on postoperative day 7 (Group I), or for late removal on postoperative day 28 (Group II). The incidence of urinary tract infections, asymptomatic bacteriuria, and urological complications were compared. Between 2007 and 2009, 130 kidney transplants were performed at one centre of which 100 were enrolled for the study, and 50 each were randomized into the two groups. Donor and recipient age, sex, native renal disease, immunosupression, number of rejection episodes, and antirejection therapy were similar in the two groups. The occurrence of symptomatic urinary tract infection during the follow-up period of 6 months was significantly less in the early stent removal group [5 out of 50 (10%) in Group I, vs 50 out of 15 (30%) in Group II, P=0.02]. Asymptomatic bacteriuria was documented in 2 out of 50 (4%) in Group I and 4 out of 50 (8%) in Group II (P=0.3). There was no statistically significant difference in the rate of ureteric leak, ureteric obstruction, or hematuria in the two groups (P=1.0). We conclude that, in kidney transplant recipients of laparoscopically retrieved live donor grafts, early stent removal at the end of first week reduces the incidence of urinary tract infection without increasing the rate of urine leak or ureteric obstruction.

Combined percutaneous and transurethral lithotripsy for forgotten ureteral stents with giant encrustation

BACKGROUND

Ureteral stents are widely used in many urologic practices. However, stents can cause significant complications including migration, fragmentation, and encrustation and it may possibly be forgotten. Successful management of a retained, encrusted stent requires combined endourological approaches.

OBJECTIVES

To present our experience with the approaches for treating forgotten ureteral stents associated with giant stone formation.

PATIENTS AND METHODS

Seventy four patients with forgotten ureteral stents were managed by different open (nephrolithotomy and/or cystolithotomy), or endoscopic procedures in our center. Among these, 11 patients had severe encrustation (stones larger than 35 mm within the bladder or kidney) and seven patients of this group, presented at our department between July 2007 and December 2010. Combined endourological procedures percutaneous nephrolithotripsy (PCNL), cystolithotripsy (CLT), transurethral lithotripsy (TUL) were performed in one or 2 separate sessions. In these 7 patients the whole of the stents, especially both ends were encrusted. Initially, cystolithotripsy, retrograde ureteroscopy and TUL were performed in the dorsal lithotomy position. Following this, a gentle attempt was made to retrieve the stent with the help of an ureteroscopic grasper. In some cases the stent was grasped by a hemostat clamp out of the urethral meatus with a gentle traction to facilitate lithotripsy in the ureter and even in the kidney. Finally, a ureteric catheter was placed adjacent to the stent for injection of radio-contrast material to delineate the renal pelvis and the calyces. Then in the same session or later in another session the patient was placed in the prone position and PCNL of the upper coil of the encrusted stent along with calculus was done and the stent was removed.

RESULTS

In 5 out of seven patients, the initial indication for stent placement was for urinary stone disease after open nephrolithotomy and pyeloplasty in other centers and in two patients after TUL. All patients underwent the procedure (s) under spinal anesthesia and all received antibiotics in preoperative period. The only available source of energy in our center was pneumatic lithotripsy.

CONCLUSIONS

Multiple endourological approaches or even open surgery are needed because of encrustations and the associated stone burden that may involve bladder, ureter and kidney. This may require single or multiple endourological sessions or rarely open surgical removal of the encrusted stents. Although, endourological management of these stents achieves success in majority of the cases with minimal complications, the best treatment that remains is prevention of this complication and to achieve this important point designing a recall system is suggested.

Antimicrobial prophylaxis in noncardiac prosthetic device recipients

BACKGROUND

Secondary antimicrobial prophylaxis involves the use of ≥ 1 antimicrobial agent just prior to the time when a diagnostic/therapeutic procedure, which may induce infection, is to be performed. In the context of this article, antimicrobial agent(s) are administered to patients with ≥ 1 implanted prosthetic device in order to prevent metastatic seeding of the device(s) during bacteremia induced by a diagnostic/therapeutic procedure. Antimicrobial agents used in this context are only administered periprocedurally. Secondary antimicrobial prophylaxis of endocarditis in recipients of cardiac prosthetic materials (including valves, shunts, conduits, and patches) has been reasonably well established. However, secondary antimicrobial prophylaxis in recipients of other types of prosthetic devices has been the subject of much controversy, with a wide variety of recommendations being made.

OBJECTIVES

The purpose of this article was to conduct a narrative review of the published literature on the topic of secondary antimicrobial prophylaxis in recipients of noncardiac prosthetic devices and make evidence-based recommendations for each type of device, where possible.

METHODS

Medline/PubMed and EMBASE databases were searched for English-language articles published from 1950 to the present (January 2012). Search terms included "prophylaxis," "antibiotics," "antimicrobials," "prosthetic devices," "prosthesis-related infections," "bacteremia," the names of the individual types of prosthetic devices, and the names of the individual procedures potentially inducing bacteremia. Articles dealing with any aspect relevant to this topic were eligible for review. The bibliographies of retrieved articles were also carefully scanned to identify any articles not previously identified.

RESULTS

Based on review of the available literature, secondary antimicrobial prophylaxis is justified in only a few specific circumstances. For recipients of prosthetic vascular grafts/stents, hemodialysis arteriovenous shunts, and ventriculoatrial/ventriculovenous shunts, prophylaxis is warranted during the initial 6 months, initial 6 weeks, and at all times after implantation/revision, respectively, when dental procedures capable of inducing high-level bacteremia are planned. Prosthetic joint recipients should receive prophylaxis in the following 3 circumstances: 1) patient is to undergo dental procedure(s) capable of inducing high-level bacteremia plus either the patient is still within 2 years of device implantation/revision or the patient has ≥ 1 risk factor for hematogenous prosthetic joint infection; 2) patient is to undergo genitourinary tract procedure(s) capable of inducing high-level bacteremia plus the patient has ≥ 1 risk factor for high-risk bacteriuria; and 3) patient is to undergo perforating dermatologic surgery on the oral mucosa or at skin sites at increased risk for surgical site infection plus patient has ≥ 1 risk factor for hematogenous prosthetic joint infection. The data are inadequate to justify secondary antimicrobial prophylaxis for recipients of other types of prosthetic devices. On the basis of 9 surveys of prescriber behavior, it is apparent that there exists, over a wide geographic area, a wide disconnect between clinical practice and the secondary antimicrobial prophylaxis guidelines issued by the professional organizations representing these prescribers. Antimicrobial agent overuse was especially problematic among orthopedic and colorectal surgeons, urologists, and family practitioners. Dentists and maxillofacial surgeons followed guidelines more closely.

CONCLUSION

Device-, procedure-, and patient characteristic-dependent factors elicited over many years have narrowed down the secondary antimicrobial prophylaxis recommendations for noncardiac prosthetic devices to a small number. Despite this, physician prescribers frequently do not follow prophylaxis guidelines established by their own professional organizations. Risk-benefit and cost-effectiveness studies have found that no prophylaxis is actually superior to universal prophylaxis, likely due to known antimicrobial toxicities, such as anaphylactic/anaphylactoid reactions and Clostridium difficile-associated disease. Much work remains in establishing and extending the scientific basis for secondary antimicrobial prophylaxis and transforming this knowledge into appropriate action by the clinician.

Bilateral hydronephrosis secondary to endometriosis managed by endoscopic ureteral stent placement in a captive Guinea baboon (Papio papio)

Spontaneous endometriosis is an estrogen-dependent, progressive and painful disease that affects a variety of nonhuman primates, including several species of baboons (Papio sp.). This case documents multimodal management of severe endometriosis in a captive female baboon within a zoological institution. An 18-yr-old, intact female Guinea baboon (Papio papio) was found to have an enlarged uterus. Fifteen months post ovariohysterctomy, scarring associated with endometrial tissue resulted in ureteral strictures, bilateral hydronephrosis, and azotemia. Cystoscopic placement of bilateral ureteral stents with fluoroscopy was performed and resulted in short-term clinical improvement. The animal's condition declined and euthanasia was elected 4 mo after ureteral stent placement. Severe endometriosis with secondary inflammation resulting in bilateral hydroureter and hydronephrosis, as well as concurrent cystitis, ureteritis, and pyelonephritis were confirmed at necropsy. Despite possible complications, ureteral stents can be considered a useful therapeutic option in patients with ureteral disease.

Use of stenting in living donor kidney transplantation: does it reduce vesicoureteral complications?

The risk of urologic complications after kidney transplantation is 0% to 30%. We studied the impact of prophylactic stent placement during transplantation by assessing the necessity for a percutaneous nephrostomy (PCN) after living kidney transplantation. From January 2003 to December 2007, 342 living donor kidney transplantations were performed. Intra- and postoperative data were collected retrospectively from 285 patients with stent and 57 without. Baseline characteristics were not significantly different between groups, except for the number of previous transplantations: 31 (11%) patients with versus 16 (28%) without stent had a history of >1 transplantation (P < .001). From patients with PCN, 55 (87%) patients in the stented group received a PCN <3 months versus 11 (100%) in the nonstented group (P = .71). The reoperation rate for urologic complications was similar in both groups (3% (stented) versus 5% (nonstented; P = .43). In multivariate analysis, risk for PCN was similar in both groups (odds ratio 1.21, 95% confidence interval 0.5-2.5). Recipient survival was not significantly different. One- and 3-year death-censored graft survival was not significantly different between stented (89% and 84%) and nonstented group (90% and 85%, P = .71 and P = .96). Ureteral stent insertion is not associated with a reduced rate of PCN placement in living donor kidney transplantation.

There is no need to stent the ureterovesical anastomosis in live renal transplants

Double-J (DJ) stents are used in urology practice for various reasons. In renal transplantation, DJ stenting is used to treat the complications like urine leak and ureteric obstruction. However, the role of routine or prophylactic DJ stenting during renal transplantation is debatable. Most of the urinary complications occurring following renal transplantation are because of poor surgical technique and transplant ureteric ischemia. Routine DJ stenting cannot be a substitute for sound surgical technique, which avoids ureteric devascularization and create watertight ureterovesical anastomosis. DJ stenting increases the risk for complications like recurrent urinary tract infection, stent encrustation, stone formation, hematuria, and severe storage lower urinary tract symptoms. Routine DJ stenting during renal transplantation is not mandatory. It can harm an immunosuppressed renal transplant recipient by predisposing to various complications.