Search

We report on the case of a 44-yr-old white man who was referred as an emergency from a local hospital to the medical intensive care unit (ICU) at our institution for progressive multiorgan failure of unknown cause. The CT scan of the abdomen showed a horseshoe kidney with extensive stone formation in both kidneys and the urinary bladder. A massively calcified double pigtail ureteral stent could also be seen in the left upper urinary tract. The stent had been placed prior to extracorporeal shock wave lithotripsy (ESWL) therapy 17 years previously. Three weeks later, after conservative treatment for heart failure and septic complications, the massively enlarged hydronephrotic left part of the horseshoe kidney was exposed and heminephroureterectomy was performed. Moreover, a right-sided pyelotomy was performed. Midline vesicotomy allowed extraction of the remaining bladder stone including the rest of the forgotten pigtail stent. The patient recovered rapidly after surgery and was discharged after 2 wk with all drains removed.

Purpose: Ureteral necrosis is a serious problem in kidney transplantation. Sometimes re-ureterocystostomy is possible, while other cases require an elaborate reconstruction to maintain kidney function. We report our experience with ileum interposition for ureteral reconstruction., Methods: After 9 years of dialysis treatment a 58-year-old patient was grafted using the left kidney of a 59-year-old donor with a cold ischemic time of 9.5 hours. The early postoperative course was uneventful apart from delayed graft function. Immunosuppression consisted of an IL-2-receptor antibody, calcineurin inhibitor, mycophenolate mofetil, and corticosteroids. Discharge serum creatinine was 2.3 mg/dL. In month 4 the patient showed a pararenal urinoma; cystoscopy revealed necrosis of the distal ureter. Operative revision showed urine leakage from the renal pelvis through the urinoma into the bladder. As the whole ureter was necrotic, a re-ureterocystostomy was not possible. The patient's own ureter had been extirpated, and the bladder was too small to do a direct anastomosis between it and the kidney. Consequently, an ileum interposition was performed., Results: The postoperative course was uneventful. Kidney function was stable with a nadir creatinine concentration of 2.0 mg/dL 18 months' posttransplantation, and 14 months' post ileal interposition the kidney function was still satisfactory, with a creatinine level of 2.0 mg/dL., Conclusion: Ureteral necrosis is a serious complication following kidney transplantation. Whenever a re-ureterocystostomy or an uretero-ureterostomy is not possible, the interposition of the ileal segment represented a safe procedure to deal with this problem.

"Obstructive uropathy" is a generic term which combines different diseases in infants and childhood. Both the upper and lower urinary tract may be affected. Diseases of the urinary tract can cause an intrinsic obstruction. Sometimes tumours may cause a compression and as secondary effect an obstruction (extrinsic). Ultrasound is the key diagnostic tool and shows dilatation of the obstructed urinary tract. But for the functional exploration of babies and toddlers, renal scanning and X-ray examinations are necessary. These examinations lead to an exposure to radiation which necessitates careful indication. Some of the congenital diseases (for example ureteropelvic junction obstruction, megaureter) show a maturation without any intervention. So one has to decide whether to wait and see or to operate. A percutaneous nephrostomy or a DJ-catheter is not often used in the treatment of obstruction in general. These forms of drainage are more often used in the treatment of stones or of extrinsic obstruction. A pyelocutaneostomy or ureterocutaneostomy is a special surgical procedure in pediatric urology for transient drainage of the upper urinary tract (megaureter). The operation of a seriously ill new-born should be done in a centre for pediatric urology and pediatric nephrology. When the upper urinary tract is dilated, patients may need an antibiotic prophylaxis, because the dilatation of the upper urinary tract increases the risk of urinary tract infections (UTI). The indication for antibiotic prophylaxis should by guided by the criteria of the APN-Consensus Paper. Long-term follow-up is necessary and should comprise ultrasound, physical examination, controlling the blood pressure, urine analysis and blood tests. The aims of diagnostics, treatment and long-term follow-up are the preservation of renal function and to protect the children from UTI. This goal must be reached under conditions that are appropriate for children and their parents.

Purpose: Whether antireflux implantation techniques are necessary in adults who undergo ileal ureteral substitution is controversial. We prospectively evaluated the correlation between reflux and renal function in 19 patients who underwent ileal ureteral substitution with no antireflux implantation technique., Materials and Methods: Followup included clinical evaluation, serum creatinine, blood gasses, excretory urogram, cystogram and dynamic selective renographic clearance on technetium mercaptotriglycine renal scans. All patients were followed for a minimum of 4 years except 2 who died 26 and 43 months postoperatively. Mean followup was 57 months (range 48 to 72)., Results: Despite reflux, renal scans indicated a significant increase in renal function in all patients. Vesico-ileal reflux was present in 9 cases and reflux in the renal pelvis occurred in only 3. Reflux occurred in only 3 of 10 patients with ileal segments longer than 15 cm., and did not reach the renal pelvis., Conclusions: Reflux appears to have no detrimental effect on renal function in adults with ileal ureters and, therefore, an antireflux procedure is unnecessary. In addition, an ileal segment longer than 15 cm. appears to safeguard the renal pelvis against visible reflux stemming from pro-grade intestinal peristalsis.

Purpose: Using a compression technique instead of the classical invagination technique in cases of total nephroureterectomy improves traction during transurethral stripping of the ureteral stump., Materials and Methods: Eight patients underwent our modified compression technique. After nephrectomy a kinked 5F ureteral catheter is attached to the ureteral stump with a double ligation. Traction on the ureteral catheter is used to achieve ureteral compression., Results: There were no intraoperative difficulties except for 1 dislodged ureteral catheter. No complications were associated with ureteral detachment or resection., Conclusion: Our technique offers an alternative to the classic invagination technique by increasing transurethral traction on the ureteral stump, while substantially decreasing the risk of ureteral catheter dislodgment.

We studied isolated muscle strips from the dilated segments of primary obstructed megaureters from 2 children and 2 adults. The preparations were obtained at ureteral reimplantation procedures and mechanical activity was compared with that of normal ureteral segments obtained at tumor nephrectomies. In contrast to normal ureters, all the preparations of the megaureters of the children showed stable spontaneous phasic activity over several hours. The adult megaureters were inactive. In both tissues a marked tonic, sustained contraction could be induced by norepinephrine. This type of response is found in calyceal and pelvic tissues only in normal upper tracts. Normal ureters responded to norepinephrine with an increase in the frequency of spontaneous phasic contractions. The qualitatively different responses of the megaureters (in comparison to normal ureteral tissue) to alpha-adrenoceptor stimulation may be due to abnormal subcellular distribution of activator calcium in these hypertrophied tissues. The observed in vitro findings may be related to the radiographic observations of impaired and uncoordinated peristalsis in primary obstructed megaureters.

The effects and the possible mode of action of some drugs were studied in isolated preparations of the human upper urinary tract. Norepinephrine, histamine and serotonin had excitatory effects, whereas isoprenaline had inhibitory effects on smooth muscle activity. Norepinephrine induced different types of mechanical activity in different tissues of the human upper urinary tract suggesting different and separate coupling mechanism between the receptors involved and the calcium pools responsible for initiation of contraction. Acetylcholine had only little effects on smooth muscle activity even in high concentrations. Contractions which were triggered by action potentials or depolarizing extracellular potassium concentrations were highly sensitive to calcium channel blockers. Other drugs with relaxing properties such as papaverine, bencyclane, flavoxate or pitofenone seem to have effects on different calcium activation or calcium storing mechanisms.

The effects of calcium agonist Bay K 8644 on mechanical activity were studied in isolated preparations of the human upper urinary tract. Bay K 8644 increased the amplitude of phasic-rhythmic contractions in calyceal segments in a concentration-dependent way. In inactive and unstimulated ureteral muscle strips, Bay K 8644 did not induce contractions. After depolarization of ureteral segments with an extracellular potassium concentration of 48 mmol./l., Bay K 8644 produced a concentration-dependent increase of contractile force and enhanced phasic-rhythmic activity. The EC50 of the drug was 7.23 X 10(8) mol./l. The potassium and calcium concentration-response-curves were shifted to the left and the maximum force development was increased. Tonic contractions induced by norepinephrine in calyceal and pelvic segments were not affected by Bay K 8644, but the tendency for phasic-rhythmic activity was increased. In contrast to calcium-antagonistic dihydropyridines like nifedipine, the dihydropyridine derivative Bay K 8644 displayed completely opposite effects, which are obviously limited to voltage-induced activation. These observations can be explained by assuming that these agents act at sites that are components or are associated with voltage-controlled calcium channels. Occupation of these sites may either increase (Bay K 8644) or decrease (nifedipine) the transmembrane calcium flux into the cell.