Pelvic reduction during pyeloplasty for antenatal hydronephrosis: does it affect outcome in ultrasound and nuclear scan postoperatively?

OBJECTIVE

To compare ultrasound (US) scan and nuclear renography findings in patients who underwent pyeloplasty with and without pelvic reduction in a randomized prospective study.

METHODS

A total of 42 patients, all prenatally diagnosed with unilateral hydronephrosis, were included. Hydronephrosis was confirmed postnatally. Twenty patients were randomly selected to undergo pyeloplasty with pelvic reduction and 22 underwent pelvis-sparing pyeloplasty. Patients were evaluated with mercaptoacetyltriglycine-3 scans on the sixth month and US scans on the first, third, and sixth months, postoperatively. Mean follow-up was 37 +/- 5.6 weeks. Statistical analyses were performed using chi-square test and significance was set as P <.05. Power analyses were performed by the NCSS-PASS program. Power value of 0.84 was calculated for a sample size of 42.

RESULTS

The anteroposterior pelvic diameter decreased significantly in the pelvic reduction group compared with pelvis-sparing group in the first- and third-month US scans. However, the difference was not significant in the sixth month. The improvements in the US findings for the pelvis-sparing group match with those of the pelvic reduction group later in the postoperative period. Pelvic reduction significantly improved the renal washout time (T(1/2)) in mercaptoacetyltriglycine-3 renography when compared with pyeloplasty group without reduction at postoperative sixth month. Differential renal function was found to be unaffected from pelvic reduction.

CONCLUSIONS

Resolution of anteroposterior diameter in US scan is more prominent in the pelvic reduction group at earlier stages of the postoperative period. Although T(1/2) decreases more prominently in the pelvic reduction group, the utility of this procedure is still indecisive. This feature can reveal possible surgical failures earlier and strengthen the values of US and renography postoperatively.

Retroperitoneal fibrosis and obstructive uropathy due to actinomycosis: case report of a treatment approach

An actinomycotic retroperitoneal infection usually occurs in the presence of an intrauterine device (IUD). It can result in pelvic inflammatory disease and diffuse retroperitoneal fibrosis. A 39-year-old patient was admitted to the emergency unit with left flank pain. A computed tomography scan of the abdomen showed bilateral hydroureteronephrosis and a retroperitoneal malignant mass. Other tumors were excluded with a colonoscopy and an upper gastrointestinal endoscopy. Results of a fine needle aspiration biopsy showed fibrosis compatible with retroperitoneal mesenteritis. Double-J stents were placed in both ureters, and immunosuppressive therapy was started. The patient had clinical and radiologic responses to the therapy. A bilateral ureterolysis and sigmoid colon resection were done. The pathology report showed fibrosis and Actinomyces israelii infection. Parenteral and oral penicillins were administered. The probability of an Actinomyces infection in patients with retroperitoneal fibrosis should be kept in mind, especially in cases in which the patient has an intrauterine device.

Genetic and developmental basis for urinary tract obstruction

Urinary tract obstruction results in obstructive nephropathy and uropathy. It is the most frequent cause of renal failure in infants and children. In the past two decades studies of transgenic models and humans have greatly enhanced our understanding of the genetic factors and developmental processes important in urinary tract obstruction. The emerging picture is that development of the urinary tract requires precise integration of a variety of progenitor cell populations of different embryonic origins. Such integration is controlled by an intricate signaling network that undergoes dynamic changes as the embryo develops. Most congenital forms of urinary tract obstruction result from the disruption of diverse factors and genetic pathways involved in these processes, especially in the morphogenesis of the urinary conduit or the functional aspects of the pyeloureteral peristaltic machinery.

GIANT SEMINAL VESICLE CYST RESEMBLING MEGAURETER WITH HYDRONEPHROSIS

Seminal vesicle cysts combined with ipsilateral renal agenesis is a rare congenital anomaly. We report an extreme case whose image resembles megaureter and hydronephrosis. A standard nephrectomy was performed and spermatozoa with flattened, cuboidal, and pseudostratified epithelium was found microscopically. The diagnosis of seminal vesicle cyst was confirmed.

[Transposition of the "conflict" vessel in obstruction of the pyeloureteral segment in children]

We studied effectiveness of the "conflict" vessel transposition in operations for hydronephrosis due to a vasoureteral conflict in children. For 1999-2007 we operated 323 children with unilateral hydronephrosis in obstruction of the pyeloureteral segment (PUS). The "conflict" vessels (CV) as a cause of the obstruction were detected in 67 patients who were divided into two groups. In group 1 (n = 33; 49.3%) we made PUS resection and created antevasal pyeloureteroanastomosis. In group 2 (n = 34; 50.7%) we made CV transposition using a graft from adventitium of the anterior pelvic wall. The degree of postoperative reduction of the calycopelvic system was the same in both groups, but in group 2 dilation decreased more rapidly and reached maximum in the first postoperative month. Simplicity of CV transposition as a method of hydronephrosis surgical treatment, its high effectiveness allow us to recommend this method for study in randomized prospective trials.

[Successful combined surgical treatment double giant ureterocele complicated by double ureterohydronephrosis, cascade lithiasis and uterine myomatosis]

A case is reported of a 58 year old patient with a diagnosis: double giant ureterocele, secondary multiple calculi of the right ureterocele, calculus of the inferior calyx of the right kidney, calculus of the terminal part of the left ureter, double ureterohydronephrosis, chronic pyelonephritis, multiple calcifying myoma of the uterus. A combined single-stage operation (panhysterectomy, deletion of multiple calculi of the right ureterocele, deletion of the calculus of the left ureterocele, crosscut right ureterectomy with excision of ureterocele, right ureterocystoneostomy by Leadbetter-Politano, installation of the double J-stent into the right kidney, crosscut and longitudinal left ureterectomy with excision of ureterocele, left ureterocystoneostomy by Leadbetter-Politano, installation of intubating drainage into the left ureter, cystostomy) followed by extracorporeal shock-wave lithotripsy were performed in this adult patient with combined pathology of the urinary system.

Type 1 diabetes and idiopathic retroperitoneal fibrosis: case report

Retroperitoneal fibrosis is characterized by the presence of a retroperitoneal tissue, consisting of chronic inflammation and marked fibrosis, which entraps the retroperitoneal organs. In two-thirds of cases, the retroperitoneal fibrosis is idiopathic. The pathogenic mechanism is not clearly identified. We report a case of idiopathic retroperitoneal fibrosis associated with type 1 diabetes mellitus. A 61-year-old woman with C peptide negative insulindependent diabetes developed retroperitoneal fibrosis revealed by bilateral hydronephrosis. Anti-GAD 65 antibodies were positive. There were no signs of autoimmune pancreatitis: no steatorrhea, normal IgG4 isotype levels, and absence of pancreas morphological abnormalities.

[Prenatal diagnosis and prognosis of fetal nephrohydrosis]

OBJECTIVE

To explore the clinical significance of prenatal ultrasonic diagnosis of fetal nephrohydrosis and its prognosis.

METHODS

Prenatal ultrasonography was performed on 9526 women at more than 20 weeks gestation, and 162 women whose anteroposterior diameter of the renal pelvis was > or = 8 mm were included in this study. The grade of fetal nephrohydrosis was classified according to Grignon grading method. The changes in fetal nephrohydrosis were observed regularly until delivery.

RESULTS

(1) The incidence of fetal encephalic fluid and Grignon grade: there were 162 fetuses with fetal nephrohydrosis among 9526 fetuses, with an incidence of 1.7%. The numbers of fetuses with Grades 1 to 5 were 71, 59, 7, 3 and 22, respectively. (2) The distribution in gestational weeks of fetal nephrohydrosis: generally, fetal nephrohydrosis was first diagnosed at (33 +/- 5) weeks, and the maximum degree of nephrohydrosis was observed at (36 +/- 3) weeks. One hundred and ten fetuses with nephrohydrosis recovered during the process of gestation, at about (37 +/- 4) weeks. (3) Poor terminations of pregnancy: there were 40 (25%) fetuses with poor terminations among totally 162 cases. Among these 40 fetuses, 3 (27%) were first diagnosed at 20 to 24 weeks within 11 fetuses, 6 (24%) were first diagnosed at 25 to 28 weeks within 20 fetuses, 14 (26%) were first diagnosed at 29 to 32 weeks within 53 fetuses, 11 (23%) were first diagnosed at 33 to 36 weeks within 48 fetuses, and 6 (20%) were first diagnosed at 37 to 40 weeks within 30 fetuses. The results demonstrate that high grade of fetal nephrohydrosis according to Grignon grading method indicates a poorer prognosis of the fetus. (4) Follow-up results: there were 122 (75%, 122/162) live and healthy neonates in total, including 110 neonates whose nephrohydrosis recovered prior to birth and 12 neonates whose nephrohydrosis recovered within 1 week after birth. These neonates all developed well without any urinary sequela within the first 2 years. There were also 20 (12%, 20/162) hydronephrotic neonates who were still diagnosed as nephrohydrosis within 1 week after birth, including 11 fetuses graded below Grignon grade 3, whose nephrohydrosis recovered 3 to 12 months after birth and who developed well without any urinary symptoms.

CONCLUSIONS

The study demonstrates that hydronephrotic fetuses who are diagnosed at earlier gestational weeks and with higher grading have poorer prognosis. The Grignon grading method can be used in the prenatal evaluation of fetal nephrohydrosis to predict the prognosis of the fetus.

[The role of the functional state of kidney mitochondria in predisposition of hydronephrotic rabits to gentamicin nephrotoxicity]

A correlation between the individual features of renal mitochondrial respiration in hydronephrotic rabbits and the degree of manifestation of gentamicin nephrotoxicity is established. The damage of kidney by the antibiotic is manifested to a greater extent in rabbits with the initial (before the administration of gentamicin) reduced ability of mitochondria to oxidize alpha-ketoglutarate, and to a lesser extent in rabbits with the reduced ability of mitochondria to oxidize palmitoilkarnitin and succinate.

Estrogen and progesterone-receptor-positive stroma as a non-tumorous proliferation in kidneys: a possible metaplastic response to obstruction

The presence of estrogen and progesterone-receptor-positive stroma is well known in renal mixed epithelial and stromal tumor, cystic nephroma, and angiomyolipoma with epithelial cysts. It has been suggested that the hormone receptor positivity in mixed epithelial and stromal tumor may be etiologically related to exogenous hormone intake-a phenomenon that has become more frequent in recent years. In the past few years, we have observed such stroma in some non-neoplastic kidneys, as well as in tumor-bearing kidneys away from the tumor. Herein we present our experience with 10 such cases. In a prospective manner, whenever we noted stroma resembling that in ovaries or müllerian organs (endometrial or cervical-like) in kidneys removed for any cause, immunohistochemical stains for estrogen and progesterone receptors were performed. There were eight males and two females among the group, with ages ranging from 11 months to 71 years. In six cases, the nephrectomies were performed for a non-functional kidney, and in three for tumors (one each of chromophobe, clear cell, and acquired cystic disease-associated renal cell carcinoma). One case was a partial nephrectomy for vesico-ureteric reflux, with upper pole hydronephrosis. Such stroma was present in nine cases as a non-mass forming proliferation around dilated, frequently inflamed pelvicalyceal system and collecting ducts. In one it was present at the periphery of an acquired cystic disease-associated renal cell carcinoma, as well as around non-tumorous cysts. The only common finding in all cases was a generalized or segmental hydronephrosis, or tumor compression-related focal obstruction. The stroma was positive for estrogen receptors in all 10 cases, and for progesterone receptors in seven. Thus, estrogen- and progesterone receptor-positive stroma can be present in the kidney, not only as a component of certain tumors, but also in association with non-neoplastic conditions. Its association with obstructive changes suggests that it may represent a metaplastic change in the renal interstitial cells surrounding these obstructed epithelial structures.

Laparoscopic nephrectomy for a girl with giant hydronephrosis of a horseshoe kidney

We report our experience of laparoscopic nephrectomy on a girl with giant hydronephrosis of a horseshoe kidney. An 8-year-old girl presented with a 4-month history of right abdominal pain. We performed laparoscopic nephrectomy for the non-functioning moiety of a horseshoe kidney secondary to uretero-pelvic junction obstruction. Laparoscopic nephrectomy is a feasible and safe method with good indications especially for children with a horseshoe kidney disease.

Inheritance of pericentric inversion in chromosome 7 through the three progenies and a newborn with congenital hydronephrosis diagnosed prenatally by fetal urine sampling

OBJECTIVE

To report the inheritance of a pericentric inversion in chromosome 7 through the three progenies, congenital hydronephrosis, and recurrent miscarriages in an extended family.

DESIGN

Case report.

SETTING

Medical Faculty of Cukurova University in Turkey.

PATIENT(S)

Referred by obstetrics and gynecology clinic.

INTERVENTION(S)

Fetal urine and lymphocytic karyotype.

MAIN OUTCOME MEASURE(S)

Chromosomal analysis from fetal urine and peripheral blood lymphocytes were performed according to standard cytogenetic methods.

RESULT(S)

We assessed an extended family in which a large pericentric inversion in chromosome 7 is segregating; one of the three progenies with the karyotype 46,XY,inv(7)(p22;q22) was heterozygote for the inversion and presented with congenital hydronephrosis. His mother, mother's brother, grandfather, grandfather's brother, and his daughter were similar for the inversion.

CONCLUSION(S)

This case describes the further molecular characterization of these breakpoints on the short or long arm of chromosome 7(p22-q22). The inv(7) is also associated with fetal wastage and may be playing a role in the etiology of the family's miscarriages. These findings can be used in clinical genetics and may be an effective tool for reproductive guidance and genetic counseling.

Laparoscopic Ureterocalicostomy for Salvage of Giant Hydronephrotic Kidney: Initial Experience

Reconstructive surgery for salvage of giant hydronephrosis is associated with unique challenges. We introduce the surgical technique of laparoscopic ureterocalicostomy for giant hydronephrosis. A transperitoneal five-port access was created and, after reflecting the colon, the lower pole of the hydronephrotic sac was excised. A wide, spatulated end-to-end ureterocaliceal anastomosis was performed. The sac was decompressed slowly in a controlled manner, which helped during dissection. At 3 months of follow-up, the patient was symptom free, and retrograde ureterography showed a wide, patent anastomosis. Laparoscopic ureterocalicostomy is technically feasible for the salvage of a giant hydronephrotic kidney and duplicates the results of open surgery.

Minimum incision endoscopic nephrectomy for giant hydronephrosis

Five consecutive patients with symptomatic giant hydronephrosis underwent minimum incision endoscopic nephrectomy. The originally huge renal specimen was retroperitoneally mobilized using both of endoscopy and direct vision, without the use of trocar ports or gas insufflation, via a single minimum incision that narrowly permitted extraction of the specimen. The specimen was successfully extracted from the incision in all patients. Technically, proper deflation of the hydronephrotic sac facilitates mobilization and enables extraction of the specimen. Median (range) size of incision, operative time, and estimated blood loss were 4 cm (3-5), 205 min (156-222), and 210 mL (110-350), respectively. No patient required blood transfusion or encountered operative complications. Postoperative convalescence was short and uneventful; all patients resumed oral intake and ambulance on the day following surgery, and were physically dischargeable from hospital after 2-3 postoperative days. Thus, this technique is a feasible, minimally invasive and safe procedure for symptomatic giant hydronephrosis.

Elective management of transitional cell carcinoma of the distal ureter: can kidney-sparing surgery be advised?

OBJECTIVE

To determine the long-term oncological outcome of patients with primary transitional cell carcinoma (TCC) of the distal ureter electively treated with either kidney-sparing surgery (KSS) or radical nephroureterectomy (RNU) in a retrospective, non-randomized, single-centre study.

PATIENTS AND METHODS

Of 43 consecutive patients with a primary solitary distal ureter TCC, 19 had KSS, consisting of distal ureter resection with bladder cuff excision and ureter reimplantation, and 24 had RNU with bladder cuff excision.

RESULTS

The median (range) age at surgery was 69 (31-86) years for the KSS group and 73 (59-87) years for the RNU group, patients in the latter having worse hydronephrotic kidneys. The median (range) follow-up was 58 (3-260) months. A recurrent bladder tumour was diagnosed after a median of 15 months in five of the 19 patients treated by KSS and after a median of 5.5 months in eight of the 24 treated by RNU. Five of the 19 patients treated by KSS and six of the 24 treated by RNU died from metastatic disease despite chemotherapy. Recurrence-free, cancer-specific and overall survival were comparable in the two groups. In two patients (11%) treated by KSS an ipsilateral upper urinary tract TCC recurred after 42 and 105 months, respectively.

CONCLUSION

Treatment by distal ureteric resection is feasible in patients with primary TCC of the distal ureter. The long-term oncological outcome seems to be comparable with that of patients treated by RNU. Furthermore, kidney preservation is advantageous if adjuvant or salvage chemotherapy is required.

Laparoscopic Nephrectomy for Pediatric Giant Hydronephrosis

OBJECTIVES

To describe our experience with pediatric laparoscopic nephrectomy (LN) and laparoscopic nephroureterectomy (LNU) for giant hydronephrosis.

METHODS

A retrospective review was conducted of all pediatric patients undergoing a transperitoneal LN or LNU. Five of these patients had giant hydronephrosis in a nonfunctioning kidney. Because of chronic infection and the massive nature of hydronephrosis, the system was internally decompressed with an end-hole stent. Partial decompression provided space in the abdomen for adequate visualization while maintaining enough turgidity to facilitate dissection.

RESULTS

Three LNs and two LNUs were performed in children with giant hydronephrosis. All cases were completed laparoscopically. Vascular anatomy and/or orientation were anomalous in all cases because of mass effect. Mean patient age was 9 years (range, 3 to 17 years). Average surgery time was 281 minutes (range, 225 to 410 minutes), and mean estimated blood loss was 27 mL (range, 5 to 50 mL). Mean time to oral intake was 6.5 hours (range, 4 to 11 hours). All patients were discharged on postoperative day 3, and there were no major or minor complications.

CONCLUSIONS

Although pediatric LN and LNU for giant hydronephrosis present unique challenges owing to the large renal volume in a small abdominal cavity, these procedures can be safely performed with careful attention to the altered anatomic relationships.

Bilateral fused pelvic kidney ectopia with a single draining ureter solved by craniolateral displacement of the kidney and Boari-modified bladder-calyceal anastomosis with bladder augmentation

A pelvic cake kidney with hydronephrosis and renal failure with the single draining ureter was reported. Frequent urination related to compression of the bladder was the most important symptom. The kidney was craniolaterally displaced, the malfunctioning ureter was replaced with the Boari-like tubularization of the bladder, and the neoureter was anastomosed with the calyx. The bladder was enlarged by intestinal augmentation.

Mature cystic renal teratoma in a 25-year-old woman with ipsilateral hydronephrosis, urinary tract infection and spontaneous abortion

Benign cystic renal teratomas are uncommon clinical entities in our environment. To the best of our knowledge, it has never been reported here. Renal teratomas are rare and most have been dismissed as retroperitoneal teratomas secondarily invading the kidney. We report a case in which benign cystic renal teratoma was associated with ipsilateral hydronephrosis, urinary tract infection and spontaneous abortion, with histological confirmation in a 25-year-old woman.

Cyclooxygenase-2 inhibitor ameliorates ureteric damage in rats with obstructed uropathy

To investigate the effect of cyclooxygenase-2 (COX-2) inhibitor on the tissue damage and fibrosis in obstructed ureters, 80 rats were studied. Celecoxib, a COX-2 inhibitor, was administered to 40 rats at the dose of 10 mg/kg per day 1 day before unilateral ligation of ureters and every day thereafter. The others, receiving unilateral ligation of ureters only, served as controls. Eight rats from each group were sacrificed for examination on days 7, 14, 21, 28 and 42 after ligation, respectively. The expressions of COX-2, prostaglandin E(2) (PGE(2)), transforming growth factor-beta(1) (TGFbeta(1)), alpha-smooth muscle actin (alpha-SMA), proliferation cell nuclear antigen (PCNA) and the apoptotic cells in the ureteric smooth muscle were examined. Hydroureter and fibrosis of the muscle layer became progressively aggravated during the period of obstruction in the ligated ureters of both groups. The severity of the hydroureter and fibrosis of muscle layer in the ligated ureters of the treated group was significantly milder than those of the control group. Expressions of COX-2 and PGE(2) were found in the smooth muscle layer of ligated ureters in the control group from day 14 after ureteric ligation, reached a peak on day 21, and then declined. Treatment with Celecoxib completely abolished the expression of COX-2 and PGE(2). The Celecoxib administration also decreased the expression of TGFbeta(1), alpha-SMA and the labeling index of apoptotic cells in the smooth muscle layer of ligated ureters in the treated group. In the contrast, treatment with Celecoxib significantly increased the expression of PCNA in the smooth muscle layer of ligated ureters in the treated group. We concluded that COX-2 inhibitor might ameliorate the damage of obstructed ureters, at least partly, via the inhibition of COX-2 and TGFbeta(1) expression.

Cardiovascular dysfunction in Zucker obese and Zucker diabetic fatty rats: role of hydronephrosis

Recent studies in our laboratory using the Zucker obese (ZO) and Zucker diabetic fatty (ZDF) rat models resulted in unexpectedly high mortality rates in all genotypes including healthy homozygous lean Zucker rats, possibly because of renal dysfunction. Therefore, we evaluated left ventricular (LV) and kidney morphology and function in young ZO, Zucker diabetic fatty obese (ZDFO), homozygous Zucker/ZDF lean (ZL), and Sprague-Dawley (SD) rats. Hydronephrosis was evident in ZL, ZO, and ZDFO but not SD kidneys. ZDFO rats exhibited impaired LV shortening and relaxation with increased arterial stiffness. LV wall thickness was lower and LV end-systolic wall stress was higher in ZDFO compared with SD rats. Plasma ANG II was lower in ZO and ZDFO rats, which may be a result of reduced renal parenchyma with hydronephrosis; norepinephrine was higher in ZDFO rats than SD controls. Covariate analysis indicated that LV end-systolic wall stress was associated with renal dysfunction. The presence of hydronephrosis and its association with LV dysfunction potentially limits the ZDF model for study of the effects of diabetes on renal and cardiovascular function.

Hydronephrosis causes salt-sensitive hypertension and impaired renal concentrating ability in mice

AIM

Hypertension is a common disease in the industrialized world and approximately 5% of all cases are secondary to kidney malfunction. We have recently shown that hydronephrosis due to partial unilateral ureteral obstruction (PUUO) causes salt-sensitive hypertension in rats. The mechanisms are still unclear, but appear to be intrarenal and primarily located to the diseased kidney. In the present study, we have developed a model for PUUO to study if hydronephrotic mice develop salt-sensitive hypertension.

METHODS

PUUO was created in 3-week-old mice (C57bl/6J). Blood pressure and heart rate were measured telemetrically in adult animals on normal and high salt diets. Metabolism cages were used to study the renal excretion of electrolytes and water. Plasma samples for renin analysis were collected and renal histological changes were evaluated.

RESULTS

All hydronephrotic animals developed salt-sensitive hypertension that correlated to the degree of hydronephrosis. In hydronephrotic animals, blood pressure increased from 114 +/- 1 mmHg on normal salt diet to 120 +/- 2 mmHg on high salt diet, compared with 103 +/- 1 to 104 +/- 1 in controls. Hydronephrotic animals showed increased diuresis and reduced ability to regulate electrolyte concentration. No differences in plasma renin concentration were found between the groups. The parenchymal weight and glomerular area of contralateral kidneys were significantly increased in the hydronephrotic animals. Histopathology of the hydronephrotic kidneys displayed areas with fibrosis, inflammation and glomerular changes.

CONCLUSION

This study provides a model for PUUO in mice and demonstrates the presence of salt-sensitive hypertension and an impaired renal concentrating ability in mice which has not been described before.

Asymptomatic spontaneous migration of double pigtail ureteral stent outside the ureter

We report a case of asymptomatic spontaneous migration outside the ureter of a double pigtail ureteral stent. This previously undescribed complication confirms the need for regular follow-up of patients with indwelling stents.

[Kidney protein complexes that inhibit gene expression in the nuclei of homotypic cells]

The comparative study of protein complexes (PCs) isolated by alcohol extraction from white rat and human nephrocytes (post-operational material) have been performed. It has been shown that PCs of white rat cells inhibit RNA synthesis in the nuclei of intact as well as nephrectomized (unilateral nephrectomy) animals. The same effect has been shown while studying the PCs of patients with hydronephrotic kidneys. At the same time the inhibition of transcription has not been detected in case of RCC kidney cancer cell PCs. The chromatography studies revealed that the active component of PCs (12 kDa protein factor) which had been detected earlier has not been shown up in cancer cells of human kidney.

Long-Term Outcome of Endopyelotomy for The Treatment of Ureteropelvic Junction Obstruction: How Long Should Patients Be Followed Up?

PURPOSE

To evaluate the long-term success rate of endopyelotomy for the treatment of ureteropelvic junction (UPJ) obstruction.

PATIENTS AND METHODS

Between January 1995 and December 2003, 85 endopyelotomies (10 percutaneous, 75 retrograde) were performed in 77 patients with a mean age of 35.2 +/- 13.9 years. The mean number of procedures per patient was 1.14, with 69 patients undergoing a single procedure. Endopyelotomies were performed using either a cold knife (N = 26), Ho:YAG laser (N = 47), or hook electrode (N = 12). Treatment success was defined as symptomatic relief with radiographic resolution or stabilization of renal function, as judged by an excretory urogram or diuretic renogram. Kaplan-Meier analysis was used to determine the long-term probability of success.

RESULTS

With a median follow-up of 37.3 months (range 3-98 months), the overall success rate was 67.5%, and the median time to failure was 7.7 months (range 1-50 months). Kaplan-Meier estimates of success were 87.8% at 6 months, 76.9% at 12 months, 72.2% at 18 months, 68.7% at 24 months, 64.8% at 36 months, and 61.6% at 60 months. The success rate was not significantly affected by the etiology, surgical approach, or incisional method. Similarly, the degree of preoperative hydronephrosis or renal function did not affect the success rate.

CONCLUSIONS

The success rate of endopyelotomy decreases as the follow-up increases. Although most failures were detected within 1 year of the procedure, it appears that follow-up of at least 36 months is required for patients who have undergone endopyelotomy for UPJ obstruction.

Comparative study of conservative and surgical management for symptomatic moderate and severe hydronephrosis in pregnancy: a prospective randomized study

BACKGROUND

To analyze the role of different measures in the treatment of acute moderate or severe symptomatic hydronephrosis in pregnancy.

METHODS

Of the 18,130 women delivering at our institution between January 2000 and December 2004, 93 patients were admitted due to symptomatic hydronephrosis. Among these, 50 patients were diagnosed with moderate or severe hydronephrosis, and were randomly treated with conservative measures (25 patients) or double pigtail stent insertion (25 patients). Renal sonography, urinalysis, serum creatinine levels, white blood cell counts, and urine culture were done in all patients at first visit. The clinical and perinatal outcomes of the two groups were compared.

RESULTS

The incidence of symptomatic hydronephrosis in pregnancy was 0.5% in our institution (93/18,130). The majority of the moderate or severe hydronephrosis (88%) cases were diagnosed after the first trimester. There were no statistically significant differences in the fetal body weight, Apgar score, preterm labor, and hospitalization day between the two groups. Among those receiving conservative treatment, five patients (5/25, 20%) failed to respond and were subsequently treated by double pigtail stent insertion successfully, compared with the surgical group, in which all patients were successfully relieved by double pigtail stent (p=0.018). Four patients receiving double pigtail stent insertion complained of stent discomfort and flank pain after the procedure (16%).

CONCLUSION

Double pigtail stent insertion is effective for the treatment of moderate or severe symptomatic hydronephrosis in pregnancy, and showed a lower failure rate than the conservative treatment. However, due to the complications and discomfort with surgical treatment, conservative treatment should still be the first choice.

Discs-large homolog 1 regulates smooth muscle orientation in the mouse ureter

Discs-large homolog 1 (DLGH1) is a mouse ortholog of the Drosophila discs-large (DLG) tumor suppressor protein, a founding member of the PDZ and MAGUK protein families. DLG proteins play important roles in regulating cell proliferation, epithelial cell polarity, and synapse formation and function. Here, we generated a null allele of Dlgh1 and studied its role in urogenital development. Dlgh1(-/-) mice developed severe urinary tract abnormalities, including congenital hydronephrosis, which is the leading cause of renal failure in infants and children. DLGH1 is expressed in the developing ureter; in its absence, the stromal cells that normally lie between the urothelial and smooth muscle layers were missing. Moreover, in ureteric smooth muscle, the circular smooth muscle cells were misaligned in a longitudinal orientation. These abnormalities in the ureter led to severely impaired ureteric peristalsis. Similar smooth muscle defects are observed frequently in patients with ureteropelvic junction obstruction, a common form of hydronephrosis. Our results suggest that (i) besides its well documented role in regulating epithelial polarity, Dlgh1 also regulates smooth muscle orientation, and (ii) human DLG1 mutations may contribute to hereditary forms of hydronephrosis.

Magnetic resonance urography for evaluating outcomes after pediatric pyeloplasty

PURPOSE

We report the role of magnetic resonance urography in children with ureteropelvic junction obstruction. Differential renal function, the single kidney glomerular filtration rate index, renal transit time, renal length and renal pelvis anteroposterior diameter were compared before and after pyeloplasty.

MATERIALS AND METHODS

Magnetic resonance urography was performed before and after pyeloplasty in 24 patients with a mean age of 1.9 years (range 3 months to 10 years). Renal length, renal transit time and renal pelvis anteroposterior diameter were determined by the radiologist. The volume of functioning renal tissue and descending aorta were segmented and the ratio of the volumes of functioning kidney tissue was used to calculate differential renal function. Rutland-Patlak plots were used to calculate single kidney glomerular filtration rate index, that is the Patlak score.

RESULTS

Mean renal pelvis renal pelvis anteroposterior diameter was 3.3 cm preoperatively and 2.5 cm postoperatively (p = 0.0003). There was no difference in average renal length (p = 0.22). Of the 24 cases 22 (92%) showed stable or improved differential renal function. Improvement in renal transit time was seen in 20 of 23 cases (87%). Of 15 patients with complete Patlak scores 14 (93%) showed postoperative improvement. Mean preoperative and postoperative differential renal function, renal transit time and Patlak score were 36% and 41% (p = 0.003), 16.2 and 8.6 minutes (p = 0.0005), and 6.6 and 11.9 ml per minute (p = 0.01), respectively.

CONCLUSIONS

Magnetic resonance urography provides superior anatomical and unprecedented functional information to fully define the preoperatively and postoperative status of corrected ureteropelvic junction obstruction. Magnetic resonance urography has the potential to become the imaging study of choice for evaluating pediatric hydronephrosis and obstructive uropathy.

Histopathological findings in nephrectomy specimens--A review of 42 cases

OBJECTIVE

This study aims at determining the histopathological findings in nephrectomy specimens in the University of Maiduguri Teaching Hospital.

METHODS

A retrospective study of all cases of nephrectomies in UMTH between January 1993 and December 2003.

RESULTS

There were 42 cases of unilateral nephrectomies, 26 (61.9%) males and 16 (38.1.9%) females giving a ratio of 1.6:1. Of these, 23 (54.8%) were benign and 19(45.2%) malignant. Chromic interstitial/pyelonephritis was the commonest indication for nephrectomy and this accounted for 28.6% of all cases. Nephroblastoma, the second commonest, accounted for 23.8% of all cases and is the major malignant indication for nephrectomies. Renal cell carcinoma and hydronephrosis accounted for 7(16.7%) cases each; polycystic kidney, transitional cell carcinoma and non-Hodgkin's lymphoma.

CONCLUSION

There is need to emphasise the importance of early diagnosis and proper treatment of urinary tract infections, since chronic interstitial/pyelonephritis is the commonest indication for nephrectomy in our environment. This will go long way in reducing the rate nephrectomies on our patients.

The magnitude of fetal renal pelvic dilatation can identify obstructive postnatal hydronephrosis, and direct postnatal evaluation and management

PURPOSE

Up to 1% of prenatal ultrasounds will detect fetal renal pelvic dilatation. We sought to evaluate and determine whether fetal renal pelvic measurements may appropriately direct prenatal counseling and postnatal evaluation and management.

MATERIALS AND METHODS

We performed a retrospective analysis of prospectively collected measurements of anteroposterior renal pelvic dilatation obtained at a single fetal maternal medicine center between 1990 and 2003. Fetuses with renal pelvic dilatation 4 mm or greater at less than 33 weeks of gestation, or 7 mm or greater at more than 33 weeks of gestation were evaluated postnatally at a single pediatric urology center. Infants with renal pelvic dilatation were evaluated with ultrasound, voiding cystourethrograms and renal scintigraphy. Renal obstruction was the main outcome measure assessed. Obstruction was defined as the need for surgery and was not based on the renal scan drainage time. Indications for surgery included declining function and increasing hydronephrosis.

RESULTS

There were 257 neonates with prenatally detected renal pelvic dilatation. A mean maximum prenatal renal pelvic dilatation of 11.8 mm was seen in 195 patients with nonobstructive dilatation. In the 62 patients with obstruction there was a nearly 2-fold increase in the mean renal pelvic dilatation (22.3 mm), which was statistically significant. Receiver operating characteristic analysis revealed that when 15 mm renal pelvic dilatation is used as a threshold it correctly discriminates obstruction in at least 80% of fetuses with a sensitivity of 73% and a specificity of 82%.

CONCLUSIONS

The magnitude of fetal renal pelvic dilatation is predictive of obstruction. Our results suggest that 15 mm renal pelvic dilatation represents a significant threshold. Receiver operating characteristic analysis provides a useful guide for prenatal counseling and may help to direct the postnatal evaluation.

Oncogenicity evaluation of resveratrol in p53(+/-) (p53 knockout) mice

A six-month study was conducted in p53(+/-) mice to evaluate the possible oncogenicity of resveratrol (3,5,4'-trihydroxy-trans-stilbene), a cancer chemopreventive agent present in grapes and other foods. p53(+/-) mice (25/sex/group) received daily gavage exposure to vehicle only (negative control), resveratrol doses of 1000, 2000, or 4000 mg/kg/day, or p-cresidine (400 mg/kg/day; positive control). No mortality was seen in mice receiving the low dose of resveratrol. However, the mid and high doses induced mortality associated with impaction of the test article in the gastrointestinal tract. Resveratrol had no effect on body weight, food consumption, or clinical signs in surviving mice in any dose group, but induced dose-related increases in liver weight and serum cholesterol in both sexes. Mild anemia was seen in male mice at the high dose only; hematologic effects were not seen in females. Histopathology identified the kidney (hydronephrosis) and urinary bladder (epithelial hyperplasia) as target tissues for resveratrol toxicity. The incidences of both benign and malignant tumors in mice exposed to resveratrol were comparable to those in vehicle controls. By contrast, the positive control article, p-cresidine, induced urinary bladder cancer in both sexes. When administered to p53(+/-) mice at its maximum tolerated dose, resveratrol demonstrates no evidence of oncogenicity.

Localization of cytochrome P450 1A1 in a specific region of hydronephrotic kidney of rat neonates lactationally exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin

Hydronephrosis is typically observed in terata caused by in utero and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), via the arylhydrocarbon receptor, but the molecular mechanism underlying its pathogenesis is largely unknown. In the present study, pregnant Holtzman rats were treated once by gavage with TCDD (1.0 microg/kg bw) or corn oil on gestation day 15. All dams were allowed to litter, and standardized litters in terms of litter size were then reciprocally cross-fostered on postnatal day (PND) 1. On PND1, pups were divided into four experimental groups: pups exposed only in utero, pups exposed only lactationally, pups not exposed via either route (vehicle control), and pups exposed via both routes. Pups were euthanized on PND21 for further analyses. The TCDD dose used was not overtly toxic to the dams or neonates. The incidence and severity of hydronephrosis were markedly high in pups exposed to TCDD lactationally, but not those exposed in utero. On PND21, cytochrome P450 (CYP) 1A1 was detected predominantly in the outer zone of the medulla of the kidney from all the pups lactationally exposed to TCDD, regardless of the occurrence of hydronephrosis. Interestingly, TCDD concentrations in the cortex, the outer zone of the medulla and the inner zone of the medulla were similar. When adult Holtzman rats were administered TCDD, the induction of CYP1A1 was immunohistochemically detected in the liver but not in the kidney 7 days postadministration. The present findings suggest that TCDD-inducible genes via an AhR-dependent mechanism may be associated with the etiology of hydronephrosis in a particular region of the kidney.

Leukocyte recruitment to the inflamed glomerulus: a critical role for platelet-derived P-selectin in the absence of rolling

The renal glomerulus is one of the few sites within the microvasculature in which leukocyte recruitment occurs in capillaries. However, due to the difficulty of directly visualizing the glomerulus, the mechanisms of leukocyte recruitment to glomerular capillaries are poorly understood. To overcome this, we rendered murine kidneys hydronephrotic to allow the visualization of the functional glomerular microvasculature during an inflammatory response. These experiments demonstrated that following infusion of anti-glomerular basement membrane (GBM) Ab, leukocytes became adherent in glomerular capillaries via a process of immediate arrest, without undergoing prior detectable rolling. However, despite the absence of rolling, this recruitment involved nonredundant roles for the P-selectin/P-selectin glycoprotein ligand-1 and beta2 integrin/ICAM-1 pathways, suggesting that a novel form of the multistep leukocyte adhesion cascade occurs in these vessels. Anti-GBM Ab also increased glomerular P-selectin expression and induced a P-selectin-independent increase in platelet accumulation. Moreover, platelet depletion prevented both the increase in glomerular P-selectin, and the leukocyte recruitment induced by anti-GBM Ab. Furthermore, depletion of neutrophils and platelets also prevented the increase in urinary protein excretion induced by anti-GBM Ab, indicating that their accumulation in glomeruli contributed to the development of renal injury. Finally, infusion of wild-type platelets into P-selectin-deficient mice restored the ability of glomeruli in these mice to support leukocyte adhesion. Together, these data indicate that anti-GBM Ab-induced leukocyte adhesion in glomeruli occurs via a novel pathway involving a nonrolling interaction mediated by platelet-derived P-selectin.

Endometriosis presenting as hydronephrosis

The most serious urological complication of endometriosis is hydronephrotic renal atrophy secondary to ureteric involvement. As only half of these patients are symptomatic, it is commonly diagnosed late and more by the clinicians awareness and suspicion of this entity. We report a case of an unmarried young female who presented primarily with left loin pain of 2-year duration. She was found to have lower ureteric stricture by an IVU done by her referring doctor. Further workup at our center showed that she had pelvic endometriosis with hydronephrosis secondary to extrinsic ureteric endometriosis. She had a first-degree relative with the same disease. She had no menstrual problems. Diagnostic laparoscopy, biopsy of the lesion, ureteric dilatation with stenting, along with hormonal treatment was given to her as first line of treatment. There was no improvement of the ureteric obstruction even after 6 months of treatment. Finally, surgical excision of the endometrioma, left oophorectomy, along with resection of the ureteric stricture with uretero-ureterostomy was done. This case report includes details of her further management and outcome along with a brief review of literature.

Multiple periorbital dermoid cysts, clefting and mental retardation: a new malformation syndrome?

We report a child with multiple anomalies that was born to healthy nonconsanguineous parents after an unremarkable pregnancy. The female infant had bilateral cleft lip and palate, bilateral toe syndactyly (second and third with no bony fusion), multiple bilateral periorbital tumors, ectropion, lagophthalmos, strabismus and prominent eyes. High frontal hairline and everted lower lip were also noted. Soon after delivery, she was referred to the 'Cleft Clinic' where she underwent cleft lip and palate repair. Seven dermoid cysts were also removed from both periorbital areas. Follow-up documented moderate developmental retardation, hypothyroidism and hydronephrosis. Although some features of our patient overlap with those described in ectrodactyly, ectodermal dysplasia and cleft lip/palate, Martinez, Zlotogora-Ogur, Filippi, Freihofer and Blepharocheilodontic syndromes, our patient has a combination of features not previously reported.

Calyceal plication with pyeloplasty in the treatment of giant hydronephrosis in children

The relief of obstruction alone is frequently not sufficient to ensure renal salvage in giant hydronephrosis. We report on our experience with plication of the renal calyces used as an adjunct to dismembered pyeloplasty in patients with giant hydronephrosis. We describe the operative technique and outcomes in ten children after a follow-up period of six months. Ten patients (six girls and four boys) with a mean age of 8.1 years (range 2-14 years) with giant hydronephrosis caused by primary ureteropelvic junction obstruction underwent a dismembered pyeloplasty followed by plication of the dilated renal calyces. The preoperative evaluation included an excretory urography, ultrasonography, 99mTc-DMSA and 99mTc-DTPA scans. The same tests were repeated six months after the operation to evaluate the outcomes. There were no intraoperative or postoperative complications. Excretory urography and ultrasonography performed six months after the operation demonstrated a significant improvement of the morphology of the operated kidneys. The kidneys shrunk in diameter from a mean of 149.5 mm (range 89-224 mm) to 93.6 mm (range 68-121 mm) and the mean diameter of the calyces was reduced from 26.9 mm (range 15-42 mm) to 14.7 mm (range 10-24 mm). Renal 99mTc-DTPA scans showed improved perfusion and renal function after surgery, with the mean elimination rate decreasing from 22.41 min (range 17.84 - 28.22 min) to 11.7 min (range 8.16-13.76 mm). 99mTc-DMSA scans demonstrated no new scars and no deterioration of renal parenchyma after surgery. We believe that plication of the renal calyces is the method of choice to be used as an adjunct to the Anderson-Hynes pyeloplasty in the treatment of paediatric patients with giant hydronephrosis.

Congenital progressive hydronephrosis (cph) is caused by an S256L mutation in aquaporin-2 that affects its phosphorylation and apical membrane accumulation

Congenital progressive hydronephrosis (cph) is a spontaneous recessive mutation that causes severe hydronephrosis and obstructive nephropathy in affected mice. The mutation has been mapped to the distal end of mouse chromosome 15, but the mutated gene has not been found. Here, we describe the identification of a single base pair change in aquaporin-2 (Aqp2) in cph mutants through genetic linkage mapping. The C-T change led to the substitution of a Ser (S256) by a Leu in the cytoplasmic tail of the Aqp2 protein, preventing its phosphorylation at S256 and the subsequent accumulation of Aqp2 on the apical membrane of the collecting duct principal cells. The interference with normal trafficking of Aqp2 by this mutation resulted in a severe urine concentration defect. cph homozygotes demonstrated polydipsia and produced a copious amount of hypotonic urine. The urine concentration defect could not be corrected by [deamino-Cys1,D-Arg8]-vasopressin (DDAVP, a vasopressin analog), characteristic of nephrogenic diabetes insipidus. The nephrogenic diabetes insipidus symptoms and the absence of developmental defects in the pyeloureteral peristaltic machinery in the mutants before the onset of hydronephrosis suggest that the congenital obstructive nephropathy is most likely a result of the polyuria. This study has revealed the genetic basis for the classical cph mutation and has provided direct genetic evidence that S256 in Aqp2 is indispensable for the apical accumulation, but not the general glycosylation or membrane association, of Aqp2.

Early prenatal diagnosis of concordant posterior urethral valves in male monochorionic twins

The association between monozygotic twins and posterior urethral valves (PUV) in postnatal life has been thoroughly described. In the fetus, the prenatal recognition of PUV is feasible. However, it has been repeatedly reported in singletons but never in monochorionic twins. We describe two cases of early prenatal diagnosis of concordant PUVs in monochorionic twins. In one of the sets, the expression of the disease was different for each twin.

Tbx18 regulates the development of the ureteral mesenchyme

Congenital malformations of the urinary tract are a major cause of renal failure in children and young adults. They are often caused by physical obstruction or by functional impairment of the peristaltic machinery of the ureter. The underlying molecular and cellular defects are, however, poorly understood. Here we present the phenotypic characterization of a new mouse model for congenital ureter malformation that revealed the molecular pathway important for the formation of the functional mesenchymal coating of the ureter. The gene encoding the T-box transcription factor Tbx18 was expressed in undifferentiated mesenchymal cells surrounding the distal ureter stalk. In Tbx18-/- mice, prospective ureteral mesenchymal cells largely dislocalized to the surface of the kidneys. The remaining ureteral mesenchymal cells showed reduced proliferation and failed to differentiate into smooth muscles, but instead became fibrous and ligamentous tissue. Absence of ureteral smooth muscles resulted in a short hydroureter and hydronephrosis at birth. Our analysis also showed that the ureteral mesenchyme derives from a distinct cell population that is separated early in kidney development from that of other mesenchymal cells of the renal system.

[Concurrent tumors in a patient with giant hydronephrosis]

OBJECTIVES

Giant hydronephrosis, defined as the presence of a liquid volume over 1000 ml within the urinary collector system, is a rare clinical entity, the diagnosis of which is an excellent exercise because it lacks of a defined clinical presentation.

METHODS/RESULTS

We report the case of a 66-year-old male under study for a suspicious digestive tumor due to a long lasting clinical picture with severe cachexia, asthenia, anemia, constipation, and abdominal mass. Radiological tests showed a great right hydronephrosis secondary to a culculus in the ureteral-pelvic junction. Simple nephrectomy was performed, evacuating 7800 ml of serous-hematic liquid from the pyelocalicial system. A histological diagnosis revealed the presence of multiple foci of transitional cell carcinoma and renal cell carcinoma associated. We review the diagnostic and therapeutic features in the literature.

CONCLUSIONS

Giant hydronephrosis represents a diagnostic dilemma. It may present as an asymptomatic process, with clinical features of abdominal organs compression (bowel or urinary obstruction) or simulate abdominal tumors, massive ascites, or cystic retroperitoneal lesions. Simple nephrectomy is the treatment of choice in most cases, due to the advanced deterioration of the renal unit. Nevertheless, in some cases, in compromised patients, percutaneous drainage may be necessary as previous or definitive treatment to avoid changes in the hemodynamic balance secondary to the sudden abdominal decompression.

Antenatal hydronephrosis: differential diagnosis, evaluation, and treatment options

The diagnosis, evaluation and management of antenatal hydronephrosis has undergone a two stage paradigm shift since the advent of prenatal ultrasonography in the early 1980s. Initially the identification of a large number of asymptomatic infants appeared to afford the surgeon the opportunity for preemptive intervention. However, it has now become apparent that antenatal hydronephrosis (AH) is far more difficult to interpret thanoriginally perceived. The initial enthusiasm for surgery has now been replaced by a much more conservative approach to ureteropelvic junction(UPJ) obstruction, multi-cystic dysplastic kidney(MCDK), vesicoureteral reflux and the non-refluxing megaureter. This review will highlight the postnatal evaluation of AH and include an overview of the Society for Fetal Urology grading system for hydronephrosis. The differential diagnosis and treatment options for UPJ obstruction, vesicoureteral reflux, MCDK, duplication anomalies, megaureter, and posterior urethral valves will be discussed.

Extracorporeal Shock Wave Lithotripsy in the Treatment of Proximal Ureteral Stones: Does the Presence and Degree of Hydronephrosis Affect Success?

OBJECTIVES

We investigated the relation between the presence and degree of stone induced hydronephrosis and the outcome of extracorporeal shock wave lithotripsy (SWL) in patients with solitary proximal ureteral stones.

METHODS

130 patients with or without hydronephrosis were treated with SWL. The degree of hydronephrosis was defined by renal ultrasound. Patients were divided into four groups according to the degree of stone induced hydronephrosis. Group 0 (24%) had no urinary system dilatation, group 1 (31.2%) had a mild dilatation of the renal pelvis, group 2 (40%) had a moderate and group 3 (4.8%) a severe dilatation of the renal pelvis and calices. The stone size, number of shock waves applied and number of sessions required to achieve stone clearance were recorded.

RESULTS

Mean stone size was 8.2 mm+/-2.5 mm. Mean time to stone clearance was 13.7 days+/-16.3. In 74.4% of patients stone clearance was observed. Additional 4.8% harbored residual fragments < or =3 mm after 3 months. Differences among the four groups in terms of stone size, time to stone clearance and treatment failure were not significant.

CONCLUSIONS

The presence or degree of hydronephrosis caused by a proximal ureteral stone does not affect the time to stone clearance or success rate after SWL.

Urinary tract involvement in a child with epidermolysis bullosa simplex

Epidermolysis bullosa is a rare disorder which may present various systemic involvement. We present a 15-month-old boy with epidermolysis bullosa simplex who was admitted with symptoms of hematuria and dysuria and discuss the pathology from a urological standpoint.

[Giant hydronephrosis of the upper left kidney in the case of complete, one-sided double pelvis]

We present the case of giant hydronephrosis in double pelvis of the left kidney. Patient was admitted to the urology department with hypertension and palpable giant mass in the abdomen. During imaging examination (CT, MRI ) the diagnosis of double pelvis and ureter on left side was established. The upper collecting system was extremely hydronephrotic and afunctional. Patient underwent partial nephrectomy - upper part of left kidney. We evacuated 9 liters of stagnated urine. After surgery blood pressure normalised, renal efficiency remained normal.

Tissue Inhibitor of Metalloproteinase-3 Plays Important Roles in the Kidney Following Unilateral Ureteral Obstruction

Tissue inhibitor of metalloproteinase-3 (Timp-3), an inhibitor of matrix-degrading enzymes, is an important molecule for maintenance of the extracellular matrix. In this study, we generated Timp-3-deficient mice and used them to examine the effect of Timp-3-deficiency on blood pressure and to investigate the role of Timp-3 in the kidney following unilateral ureteral obstruction. The blood pressure and heart rate of Timp-3-deficient mice were not significantly different from those of wild-type mice. On the other hand, the obstructed kidneys of Timp-3-deficient mice developed more severe hydronephrosis than those of wild-type animals. Matrix metalloproteinase activities assessed by in situ zymography and transforming growth factor-beta expression were elevated in Timp-3-deficient mice. The renal tissues were thinner and the ratio of renal medulla to cortex was significantly lower in the obstructed Timp-3-deficient kidneys. These findings indicate that Timp-3-deficiency does not substantially affect the blood pressure in mice, and that Timp-3 plays an important role in the maintenance of renal macrostructure after unilateral ureteral obstruction.

Hydronephrosis associated with antiurothelial and antinuclear autoantibodies in BALB/c-Fcgr2b-/-Pdcd1-/- mice

Because most autoimmune diseases are polygenic, analysis of the synergistic involvement of various immune regulators is essential for a complete understanding of the molecular pathology of these diseases. We report the regulation of autoimmune diseases by epistatic effects of two immunoinhibitory receptors, low affinity type IIb Fc receptor for IgG (FcγRIIB) and programmed cell death 1 (PD-1). Approximately one third of the BALB/c-Fcgr2b^−/−Pdcd1^−/− mice developed autoimmune hydronephrosis, which is not observed in either BALB/c-Fcgr2b^−/− or BALB/c-Pdcd1^−/− mice. Hydronephrotic mice produced autoantibodies (autoAbs) against urothelial antigens, including uroplakin IIIa, and these antibodies were deposited on the urothelial cells of the urinary bladder. In addition, ∼15% of the BALB/c-Fcgr2b^−/−Pdcd1^−/− mice produced antinuclear autoAbs. In contrast, the frequency of the autoimmune cardiomyopathy and the production of anti–parietal cell autoAb, which were observed in BALB/c-Pdcd1^−/− mice, were not affected by the additional FcγRIIB deficiency. These observations suggest cross talk between two immunoinhibitory receptors, FcγRIIB and PD-1, on the regulation of autoimmune diseases.