Late complications of ureteral stents

OBJECTIVE: To review morbidity and late complications of ureteral stent insertion and to specifically evaluate hydronephrosis as a radiologic finding of obstruction in the presence of an indwelling ureteral stent. METHODS: In this prospective study, we evaluated 110 stented kidneys in a group of 90 patients. Of 110 stents, 52 were left in place for 3 months, 23 for 6 months, 11 for 9 months, and 24 for up to 12 months. With the stent in place, patients were followed by plain abdominal X-ray 1 and 30 days after stenting. Further follow-up was performed through ultrasound and plain film every 3 months until scheduled date for stent removal or the appearance of complications. RESULTS: In 11 of 110 cases (10%) there was stent fragmentation and in 9 (8.2%) stent migration. In 10 cases (9.1%), there was no change in the severity of the hydronephrosis, but because of flank pain or urinary tract infection with fever, the stents had to be removed. In 6 cases (5.4%) hydronephrosis developed or worsened after stenting. Of the 110 ureteral stents, 32.7% had to be removed because of late complications. CONCLUSIONS: Although ureteral stenting is undoubtedly an important procedure for the release of ureteral obstruction, the indications for stent insertion should be carefully considered in each patient. Late complications of ureteral stents are frequent and appear in one third of the patients. Close follow-up of stented patients is valuable in early detection of morbidity or complications, and in such cases the stent should be removed or exchanged as soon as possible.     

Success of ureteral stents for intrinsic ureteral obstruction

PURPOSE: Previous reports suggest a high success rate for retrograde ureteral stenting for intrinsic ureteral obstruction, but few preoperative predictors of success have been offered. We reviewed our experience to look for factors that suggest failure of stents for intrinsic ureteral obstruction. MATERIALS AND METHODS: We retrospectively reviewed the outcome of retrograde ureteral stent placement for intrinsic ureteral obstruction without concurrent or intended definitive management of the obstruction. RESULTS: Thirty-eight patients treated for intrinsic ureteral obstruction, representing 41 ureteral units (UUs), were monitored for an average of 25.5 months. The overall success rate was 88%. Of the successes, 13 UUs had definitive therapy to permanently remove the cause of obstruction, obstruction resolved in 12 UUs after stent placement, and 11 UUs were managed with indwelling stents. Therapy failed in five UUs, with a median time to failure of 1.9 months. Of the UUs in which failure occurred, three failures were caused by misdiagnosis; in the remaining two, the stent did not correct the obstruction. On univariate analysis, male sex (P = 0.006), increased creatinine level as a presenting symptom (P = 0.002), and more severe preoperative hydronephrosis (P = 0.042) were predictive of failure. Adverse events were low, with complications from stenting occurring on only four of 41 UUs. CONCLUSION: If initial stent placement was possible, intrinsic ureteral obstruction was managed successfully in 88% of patients. Given high success and minimal complications, retrograde placement of ureteral stents can be performed to treat patients with intrinsic ureteral obstruction. Treatment failure is more likely to occur in men and patients with severe hydronephrosis or an elevated creatinine level.     

The thermo-expandable metallic ureteric stent: an 11-year follow-up

OBJECTIVE

To review our long‐term use of the thermo‐expandable metallic ureteric stent, (model 051, PNN Medical, Denmark) for ureteric obstruction, and review current reports on its use.

PATIENTS AND METHODS

Data were collected prospectively on all patients who had a Memokath 051 ureteric stent inserted between November 1996 and November 2007. The standard stent, and wide and dual expansion versions were used. The stricture characteristics were recorded in a standard way. All stents were inserted by one surgeon in the UK and internationally, following a standard protocol.

RESULTS

In all, 74 stents were inserted into 55 patients in the study period (mean age 60 years, range 11–90). The indications for metallic stenting included primary stenting for malignancy, failed conventional open and endoscopic techniques, palliation, and where significant comorbidity limited repetitive stent changes. In 28 patients the obstruction was caused by malignancy, whereas in 27 it was caused by recurrent benign disease. The mean (range) hospital stay was 1.43 (0–7) days. Imaging after insertion showed normal or improved functional drainage in all but three patients, with immediate complications including urinary extravasation (one), poor thermo‐expansion (one) and equipment failure (locking assembly) (one). Late complications included migration (13), encrustation (two) and fungal infections (three). In all, 14 patients needed reinsertion (mean of 7.1 months, range 1–14) after insertion for migration (eight), encrustation (two), stricture progression (three) and incorrect stent length (one). Overall, 29 patients have died with the stents in‐situ. The mean (range) follow‐up was 16 (4–98) months.

CONCLUSIONS

The thermo‐expandable metallic Memokath 051 ureteric stent offers effective and durable long‐term relief from ureteric obstruction, and is a safe alternative to conventional JJ stenting. In addition there is an emerging role in palliation and the primary management of ureteric strictures.     

Metallic stents for malignant and benign ureteric obstruction

OBJECTIVE: To report our experience of using metallic stents to treat ureteric obstruction caused by malignant or benign disease. PATIENTS AND METHODS: Nine patients with obstruction in 11 ureters caused by malignant or benign disease (mean age 61 years, range 35-82, mean follow-up 7 months, range 3-11) were treated using metallic stents. A balloon-expandable metallic stent was used in one patient and self-expandable metallic stents in the remaining eight. All stents were inserted via a percutaneous antegrade approach. RESULTS: Of the 11 ureters, nine remained patent with no further manipulation during the follow-up of 3-11 months. An additional stent was placed in continuity with the first in two ureters of two patients at 4 and 5 weeks after the first procedure because of persistent obstruction. After the second intervention, their obstruction was improved. Transient vesico-ureteric reflux occurred in two of three stented distal ureters, but the reflux resolved spontaneously within 2 months after stent implantation. Ureteric patency was maintained in all patients and no major complications related to stenting occurred during the follow-up. Two patients died from cervical cancer at 3 and 5 months after stenting. CONCLUSION: In patients with difficult ureteric obstructions a metallic stent provides a safe and effective alternative to an indwelling double-pigtail catheter or percutaneous nephrostomy.     

Is routine ureteric stenting needed in kidney transplantation? A randomized trial

BACKGROUND: Whether routine ureteric stenting in low-urological-risk patients reduces the risk of urological complications in kidney transplantation is not established. METHODS: Eligible patients were recipients of single-organ renal transplants with normal lower urinary tracts. Patients were randomized intraoperatively to receive either routine stenting or stenting only in the event of technical difficulties with the anastomosis. All patients underwent Lich-Gregoire ureteroneocystostomy. RESULTS: Between June 1994 and December 1997, 331 kidney transplants were performed at a single center, 305 patients were eligible, and 280 patients were enrolled and randomized. Donor and recipient age, sex, donor source, whether first or subsequent grafts, ureteric length, native renal disease, and immunosuppression were similar in each group. In the no-routine-stenting group 6 of 137 patients (4.4%) received stents after randomization for intraoperative events that in the surgeon's opinion required use of a stent. In an intention-to-treat analysis there was no difference between groups in the primary outcome cluster of obstruction or leak [routine stenting 5 of 143 (3.5%) vs. no routine stenting 9 of 137 (6.6%); P=0.23], or in either of these complications analyzed separately. All urological complications were successfully managed without major morbidity. Living donor organs and shorter ureteric length (after trimming) were univariate risk factors for leaks, although increasing donor age was associated with obstruction. CONCLUSIONS: Routine ureteric stenting is unnecessary in kidney transplantation in patients at low risk for urological complications. Careful surgical technique with selective stenting of problematic anastomoses yields similar results.     

Double J stents. A review of 100 patients

Double J stents have been advocated for drainage or splintage of the ureter. One hundred and thirty-eight attempts at stent insertion were made in 100 patients. In 78% of attempts the stent was satisfactorily placed. Their use in retroperitoneal fibrosis, ureteric trauma and acute hydronephrosis of pregnancy has been encouraging. Poor results have been obtained in patients with malignant obstruction or tuberculous stricture.     

Urological complications of renal transplantation: the impact of double J ureteric stents.

In a 10 year series of 350 consecutive renal transplant operations, the overall urological complication rate was 7.7%. During this period double J stents were introduced and were used either in the treatment of actual urological complications or as a prophylactic measure to protect ureters which had been damaged at retrieval. A total of 34 double J stents were used in 33 patients. The indications were: ureteric obstruction (n = 13), urinary leak (n = 5), short transplant ureter anastomosed using an extravesical ureteroneocystostomy (n = 10) and ureteric injury at the time of organ retrieval (n = 6). Thirty-two double J stents were inserted at open operation and two were inserted by an antegrade method after percutaneous nephrostomy. Improvement in renal function occurred in 16 out of the 18 cases of urological complications. No kidneys were lost and there were no deaths as a direct result of these complications. In a number of cases the insertion of a double J stent was the only treatment, thus eliminating the need for more complex surgery. All 16 patients who had a ureteric stent inserted as a prophylactic measure at the time of transplantation made uncomplicated postoperative recoveries. Urinary tract infection was relatively common (27%) after double J stent insertion, but other complications were rare. In conclusion, double J stents have proved to be a useful adjunct in the management of renal transplant related urological complications.     

An experimental study of self-expanding ureteric metallic stents: macroscopic and microscopic changes in the canine ureter

OBJECTIVE: To evaluate the efficacy and safety of self-expanding metallic stents after insertion into the canine ureter. MATERIALS AND METHODS: Actively expanding metallic (Nitinol) stents (diameter 8-10 mm, length 4-6 cm) were placed in eight mongrel dogs (18-34 kg). Under general anaesthesia, a midline abdominal incision was made and a stent inserted directly into the ureter through a small incision; each animal was stented on one side. The dogs were assessed after 6 or 19 days or 2, 5 (two), 6 (two) and 7 months. Ureteric specimens were evaluated both macroscopically and microscopically. RESULTS: Macroscopically there was no leakage of urine in any of the animals. On day 6 the inserted stent was patent despite blood clots in the mesh. The lumen was smooth and shiny in three dogs examined at 5, 6 and 7 months. One of the two dogs assessed at both 5 and 6 months had hydronephrosis associated with papillary hyper-epithelialization inside the stent, while the other animals had no dilatation of the renal pelvis. Microscopically there was loss of epithelium and bleeding of the ureteric wall at 6 days. Epithelial regeneration started after 19 days and was complete in the lumen at 2 months, with the stent incorporated into the wall of the ureter. Epithelialization was maintained up to 7 months, after which the problem of urothelial hyperplasia persisted, but an adequate lumen was maintained by epithelial regeneration. This epithelium was smooth and shiny, and composed of thin layers of cells. CONCLUSION: Self-expanding metallic stents may be effective if hyperplastic epithelialization does not occur, as the stent was epithelialized within 2 months and the regenerated epithelium maintained for up to 7 months. Metallic stents may be useful for treating patients with renal failure caused by ureteric stenosis from malignant tumours.     

Early and late complications of double pigtail ureteral stent

OBJECTIVES: To analyze the early and late complications of indwelling ureteral stents in a series of 146 patients with nephroureteral lithiasis. MATERIALS AND METHODS: 146 patients with obstructing nephrolitiasis were treated for urinary diversion with double pigtail ureteral stent before extracorporeal shock-wave lithotripsy (ESWL) and following ureterorenoscopic treatment of lithiasis. All patients were scheduled for stent removal or replacement at specific 3-month intervals until stone-free status was achieved. RESULTS: Early complications during the first 4 weeks after stent insertion were stent discomfort (37.6%), irritative bladder symptoms (18.8%), hematuria (18.1%), bacteriuria (15.2%), fever >104 degrees F (12.3%) and flank pain (25.3%); late complications included hydronephrosis (5.7%), and stent migration (9.5%), encrustation (21.6%), fragmentation (1.9%) and breakage (1.3%). CONCLUSIONS: Ureteral stents have proven to be an invaluable tool for endourologists. Morbidity is minimal for up to three months but longer indwelling times are associated with an increasing frequency of incrustation, infections, secondary stone formation and obstruction of the stented tract.     

Prospective evaluation of ureteral stent durability in patients with chronic ureteral obstruction

Objectives. To prospectively evaluate the durability of ureteral stents in patients with chronic ureteral obstruction.Methods. Twenty-nine renal units from 22 patients with known chronic ureteral obstruction treated with indwelling ureteral stents were studied at 3, 6, 9, and 12 months after initial stent placement (7 to 8F Percuflex) by abdominal x-ray, serum creatinine, and renal and bladder ultrasonography. Renal ultrasound scans were performed by a single senior radiologist with specific attention paid to any increase in hydronephrosis and to the presence of ureteral jets. The stent was changed when calcifications were seen along the stent on abdominal x-ray, if an increase in serum creatinine occurred, or if any increase in hydronephrosis or absence of ureteral jets was seen on ultrasonography. In addition, the stents were changed if new-onset flank pain and/or pyelonephritis developed. If none of the above occurred, the stents were changed after 12 months.Results. Two patients died of metastatic cancer, leaving 25 renal units available for follow-up. The mean and median time to stent change were 6 months. At 3, 6, 9, and 12 months, the number of renal units that did not meet the criteria warranting stent change was 18 (72%), 12 (48%), 6 (24%), and 2 (8%), respectively. Only 2 (8%) of 25 renal units did not meet any exclusion criteria at 12 months. The most common reasons for requiring the stent to be changed were new-onset flank pain in 8 (35%), an increase in serum creatinine in 7 (30%), and new-onset or increased hydronephrosis in 7 (30%). No criteria were useful in predicting how long stents could be maintained in an individual patient.Conclusions. The stents were maintained for more than 6 months in 12 (48%) of 25 renal units. However, very few patients were able to maintain chronic ureteral stents for 12 months without requiring stent change based on our criteria.     

The natural history of hydronephrosis after radical hysterectomy with no intraoperatively recognisable injury to the ureter: a prospective study

OBJECTIVE: To investigate, in a prospective study, the natural history of hydronephrosis of the urinary tract after radical hysterectomy. PATIENTS AND METHODS: From December 1997 to March 2001, 34 patients with localized cervical cancer underwent radical hysterectomy by one gynaecologist, with no intraoperatively identifiable injury to the ureter. Intravenous urography was used routinely before and at 2 and 4 weeks after surgery. The degree of hydronephrosis was graded I-IV. RESULTS: Urography before surgery showed no abnormal finding in any of the patients, except in one with a unilateral duplex kidney. Hydronephrosis was found in 10 units in the upper tract (grade II in eight, III in one and IV in one) in seven patients (21%) 2 weeks after surgery (one right, three left and three bilateral). All the ureteric narrowing was in the distal ureter. The hydronephrosis disappeared in four units in three patients, but became worse in two units in two patients with bilateral pathology in the fourth week. At 3 months after surgery no hydronephrosis had deteriorated and the hydronephrosis in all units had disappeared by 6 months. The presence of hydronephrosis was significantly correlated with pathological stage and age (P < 0.05). CONCLUSION: Hydronephrosis was detected after radical hysterectomy even with no intraoperatively recognisable injury to the ureter, but in most the hydronephrosis improved spontaneously and needed no ureteric stenting or surgical intervention.     

The use of internalised ureteric stents in renal transplant recipients

Since 1982, we have used internal indwelling ureteric stents for the management and prevention of ureteric reconstruction complications in 28 renal allograft recipients. A total of 30 stents were placed in 18 patients either diagnostically or therapeutically in the management of allograft ureteric obstruction. In 16 patients internal stents were placed at the time of reconstruction for primary ureteropyelostomy (3), secondary ureteropyelostomy (8), repeat reimplant (3) and repair of ureteric or pelviureteric junction injury (2). Complications included 3 episodes of transplant pyelonephritis, proximal stent migration (1), persistent bacteriuria (1) and prolonged healing of a ureteropyelostomy (1). Internalised ureteric stenting is a safe and effective means of managing or preventing ureteric reconstruction complications in renal transplant recipients.     

Extracorporeal shock wave lithotripsy for large renal calculi: the role of ureteral stents. A randomized trial

Ureteral stents reduce complications after extracorporeal shock wave lithotripsy (ESWL*) and contribute to successful stone passage. However, some reports note complications that are attributed to indwelling ureteral stents. We randomized 64 patients with large renal calculi (stone burden more than 200 mm.2) for in situ treatment or treatment with a prophylactically inserted stent. We used a 6Ch round stent with single-coiled ends or a triangular shaped stent with double-coiled ends. Patients were treated with a Siemens Lithostar lithotriptor. After 3 months we evaluated the results of treatment and post-ESWL morbidity. Of the in situ group (23 patients) treatment complications consisted of fever in 3, pyelonephritis in 1 and steinstrasse in 3. After 3 months 8 patients (35%) were free of stones. Of the stented population (41 patients) treatment complications consisted of fever in 7, pyelonephritis in 1, steinstrasse in 6 and bladder discomfort in almost half of the patients. Stent calcification and stent migration were also seen in 7 and 10 patients, respectively. Calcified stents had been in situ longer than noncalcified stents. The round stents migrated and calcified more often than the more rigid triangular stents. After 3 months 18 of the stented patients were stone-free (44%). We conclude that ureteral stents do not reduce post-ESWL complications. They are clearly associated with morbidity and do not improve stone passage markedly. Therefore, patients with a stone burden of more than 200 mm.2 should be treated in situ without auxiliary stenting.     

Die Duplex-Doppel-J-Schiene bei intrinsischen und extrinsischen Harnleiterengen

Background

Duplex or twin ureteral stenting has previously been described as a viable option for patients where single double-J ureteral stenting has failed in order to avoid nephrostomies or further surgical intervention. We assessed a series of 20 patients at our institution after unsuccessful primary single ureteral stenting where parallel ureteral stents were inserted.

Methods

Between 2003 and 2009, 20 patients underwent double-J ureteral stenting for ureteral compression or ureteral strictures. After failure of single stenting two ureteral stents were consecutively inserted into the ureter in a parallel fashion after dilating the ureter up to 14 F. The second stent was passed over a hydrophilic guidewire while holding the first stent secure to prevent dislocation.

Results

In all patients the insertion of two parallel stents was technically possible. In 8 of 12 patients with extrinsic tumor compression the stents provided sufficient drainage (67%). When the stricture was due to surgery or radiation two of three patients were successfully diverted with twin stents. In five patients with a ureteral stricture due to malignant disease the stenting did not provide sufficient drainage and a nephrostomy had to be placed after a mean duration of 19 days. Two of those patients were later managed with a pyelovesical bypass. Three patients were later managed with a ureterocystoneostomy (psoas hitch). In four of five patients with benign disease a long-term management was feasible. The patient with retroperitoneal fibrosis developed immediate hydronephrosis and severe flank pain and ultimately underwent an ileal ureter replacement. In three patients with a benign ureteral stenosis after stone therapy, hysterectomy, or colon ureter replacement, a temporary duplex stenting sufficiently resolved the hydronephrosis for spontaneous urine passage. In one patient the duplex stenting prevented a kidney stone from dislocating into the ureter during lithotripsy.

Conclusions

Duplex or twin (double) ureteral stenting is a valid option in selected patients to avoid the placement of a nephrostomy. Severe stenosis may however demand a nephrostomy insertion or more invasive procedures in the later course. For certain benign ureteral strictures a therapeutic dilating effect of the two ureteral stents that makes further intervention unnecessary can be discussed.     

The ‘buoy’ stent: evaluation of a prototype indwelling ureteric stent in a porcine model

OBJECTIVE

To assess a prototype ureteric ‘buoy’ stent with a 10 F upper body tapering to a 3F tail, developed to potentially reduce stent‐related irritative symptoms while providing an adequate mould for healing after endopyelotomy.

MATERIALS AND METHODS

Eighteen Yucatan minipigs had the stent placed either into the intact ureter (phase I) or after Acucise proximal endoureterotomy (phase II). Buoy stents were compared to 10/7 F endopyelotomy stents and to standard 7 F stents in phases I and II, respectively. The pigs were assessed for vesico‐ureteric reflux, hydronephrosis and infection, before stent insertion and at harvest. Stents were weighed before and after placement and the removal force was measured. Pressure/flow studies, antegrade nephrostograms and specimens for histopathology from the renal pelvis, ureter and vesico‐ureteric junction (VUJ) were obtained at harvest.

RESULTS

Thirteen minipigs survived the entire study. Ureteric flow with the stents in situ was better for buoy stents than for 10/7 F stents (P < 0.005). Ureteric flow after endoureterotomy and subsequent stent removal was similar for buoy stents and standard 7 F stents. None of the stents refluxed. There was no difference between stents in removal force, weight change or incidence of hydronephrosis. At 1 and 12 weeks, buoy stents tended to produce lower histopathological alteration scores than control stents, especially at the VUJ (phase I, 2.0 vs 3.9, P = 0.092; phase II, 0.6 vs 1.7, P = 0.18).

CONCLUSIONS

The novel buoy stents are easily placed and removed via the urethra. They can cause less VUJ inflammation than standard stents while allowing for adequate ureteric flow and healing after proximal endoureterotomy.     

Predictors of morbidity in patients with indwelling ureteric stents: results of a prospective study using the validated Ureteric Stent Symptoms Questionnaire

Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? Although it has long been known that ureteric stenting is associated with significant morbidity in a high proportion of patients, predictors of morbidity remain largely elusive. In a multivariable analysis of potential predictors of morbidity using the Ureteric Stent Symptoms Questionnaire, an easy‐to‐determine variable, i.e. the location of stent distal loop with respect to body midline, emerged as the strongest predictor of morbidity. Patients with stent distal loop crossing the midline experienced worse symptoms. The visualization of stent distal loop may, thus, help identify patients at higher risk of morbidity requiring early management. OBJECTIVE To assess the predictors of morbidity in patients with indwelling ureteric stents using a validated questionnaire. PATIENTS AND METHODS Eighty‐six consecutive patients with indwelling double‐J ureteric stent of different length and size enrolled at an Italian tertiary academic centre were prospectively evaluated with the Italian‐validated Ureteric Stent Symptoms Questionnaire (USSQ), which explores the stent‐related symptoms in six domains. Ureteric stents were placed for benign ureteric obstruction or after uncomplicated ureterorenoscopy, and were all removed after 28 days. The questionnaire was administered on days 7 and 28 after stent placement and on day 28 after removal. A plain abdominal X‐ray was performed on days 7 and 28 after placement to determine stent location. Univariable and multivariable analyses tested the association of patient age, sex and body mass index (BMI), and stent side, length, calibre and distal loop location, with the index score of the various domains on days 7 and 28. RESULTS All patients completed the study. At multivariable analysis, on day 7, sex, BMI and stent calibre were significantly associated with one domain (general health, body pain and work performance, respectively), while location of stent distal loop was significantly associated with five domains (urinary symptoms, body pain, general health, work performanc, and sexual matters). On day 28, body mass index was significantly associated with two domains (body pain and general health), while location of stent distal loop remained significantly associated with the same five domains (urinary symptoms, body pain, general health, work performance and sexual matters). CONCLUSION Location of stent distal loop with respect to midline had the strongest association with most domains of the USSQ on both days 7 and 28 after stent placement. The visualization of stent distal loop crossing the midline may therefore identify patients at higher risk of post‐procedural morbidity requiring early management.     

The self-expanding metallic ureteric stent in the long-term management of benign ureteric strictures

OBJECTIVE: To evaluate and assess the long-term complications of using the thermo-expandable, nickel-titanium alloy stent (Memokath 051, Engineers & Doctors A/S, Hornbaek, Denmark) for managing benign ureteric strictures. PATIENTS AND METHODS: Over a 3-year period, 13 Memokath stents were inserted in 11 patients (mean age 58 years, range 35-85) with 12 lower ureteric strictures. The cause of the stricture was benign in all cases, i.e. radiation fibrosis in three, retroperitoneal fibrosis, ischaemic uretero-ileal anastomosis and scarring after ureteroscopy in two each, and diathermy damage, extraluminal endometriosis and stone passage in one each. Four stents were 9 F with proximal expansion to 17 F and the other nine used were 10.5 F with proximal expansion to 20 F. The patients were followed for a mean (range) of 18 (1.5-33) months. RESULTS: No complications or side-effects occurred with nine stents; four stents were removed at a mean (range) of 16.3 (4-33) months. Three of these had become encrusted, two of which had been placed in patients who had either a history of stone disease or recurrent urinary tract infection. The other stent had migrated. CONCLUSION: The Memokath stent appears to have a useful role in managing benign ureteric strictures, but it must be closely monitored in patients who are predisposed to encrustation.     

Febrile complications following insertion of 100 double-J ureteral stents

BACKGROUND AND PURPOSE: Implanted foreign bodies are associated with a higher risk of infection. Little has been published on infectious complications associated with ureteral double-J stents. The aim of this study was to define risk factors and characterize the febrile complications of the insertion of double-J stents. PATIENTS AND METHODS: One hundred consecutive cases of retrograde stent insertion (55 men and 45 women) were evaluated retrospectively. Eighty-one patients had an obstructing stone, either in the ureter or at the ureteropelvic junction; 10 had an obstructing tumor; and 9 had hydronephrosis and pain without calculi. Risk assessment was calculated for two major categories: urgent (N = 47) and elective (N = 53) insertion. Potentially confounding factors such as age, sex, accompanying medical problems, and types of prophylaxis were assessed. All but six patients received prophylactic antibiotics prior to stent insertion. RESULTS: All thirteen patients who had fever at the initial evaluation underwent urgent stent insertion. Of the 87 afebrile patients (53 elective and 34 urgent insertions), 22 (25%) developed fever (> or = 38 degrees C) after the procedure. Fever developed in 19 (56%) of the 34 urgent-insertion group who were not originally febrile as opposed to 3 (6%) of the elective-insertion group (P < 0.001). Six of these 22 patients (27%) had a positive urine culture after insertion. None had a positive blood culture, including the 13 patients who underwent the procedure while febrile. CONCLUSIONS: Urgent insertion of a double-J stent is associated with a high risk of fever but a favorable outcome.     

Ureteric stenting after ureteroscopy for ureteric stones: a prospective randomized study assessing symptoms and complications

OBJECTIVE: To compare patients with and with no stenting after ureteroscopy for ureteric calculi, as placing such stents is routine, although many patients complain of pain and urinary symptoms. PATIENTS AND METHODS: In all, 45 patients with ureteric calculi amenable to ureteroscopic management were prospectively randomized into a stented (23) or an unstented (22) group. Standard ureteroscopic basketing and lithotripsy was used, through a ureteroscope (8.5 F) with or without ureteric dilatation. Symptom questionnaires were completed by the patients after treatment, and they were followed radiographically to assess stone-free rate and evidence of obstruction. RESULTS: There was no statistically significant difference in age, stone size, operative duration or hospital stay between the groups (P > 0.05). Furthermore, there was no statistical difference in flank pain or urinary symptoms (P > 0.05), except haematuria, between the groups; haematuria was more severe and prolonged in the stented group (P = 0.001). CONCLUSIONS: Uncomplicated ureteroscopy for removing calculi is safe with no stent after treatment, and after considering complications and side-effects we think that the routine use of ureteric stents after uncomplicated ureteroscopy for stone extraction is unnecessary.     

Management of malignant biliary stricture with self-expanding metallic stent

Background: Self-expanding metallic mesh stents are designed to remain patent longer than polyethylene (PE) stents, which generally clog in 3 to 4 months. Though more expensive, metal stents may therefore be a better choice for malignant strictures. Methods: From January 1991 to October 1995, we performed ERCP in 212 patients with malignant or benign strictures, and 34 ultimately had insertion of a metallic stent. These stents were placed by the percutaneous transhepatic route in 17 patients and endoscopically in 17. Results: Metallic stent insertion was successful in each case and relieved the preoperative jaundice and cholangitis. There were no procedure-related deaths; complications were pancreatitis (one) and hemorrhage (one). Overall stent patency was 6.2 months. Three of 34 stents occluded due to tumor ingrowth at 3, 4.5, and 8 months and were treated by placing a new PE stent through the blocked metal stent. The remaining 31 stents remained patent until patient death (n= 15, mean survival = 4.9 months) or are still open (n= 16, mean patency = 12.2 months). Conclusions: Self-expanding metal stents provide effective palliation of malignant biliary strictures and should be considered an alternative to open surgery. Metal stents remain patent much longer than PE stents and usually a single session of metal stenting can palliate biliary obstruction for life. Received: 20 March 1996/Accepted: 9 May 1996