Ureteral obstruction in the neonatal rat: Renal nerves modulate hemodynamic effects

In the neonate, chronic unilateral ureteral obstruction (UUO) reduces renal blood flow (RBF) of the ipsilateral kidney and increases RBF of the opposite kidney. To determine whether renal nerves mediate or modulate these responses complete left UUO in the neonatal rat was used as a model of severe obstructive uropathy, and was compared with sham-operated controls. At 24–28 days of age, animals underwent left or right mechanical renal denervation or left sham renal denervation. One week after denervation, animals were anesthetized and blood pressure and heart reate were measured. Cardiac output and RBF were determined by the radioactive microsphere technique. UUO increased blood pressure and heart rate, and decreased RBF in the obstructed kidney, regardless of denervation. While left UUO increased RBF to the intact opposite kidney in rats with left renal denervation, this was attenuated by right renal denervation. Thus, in the neonatal rat, UUO modulates systemic renal hemodynamics, possibly through activation of the renin-angiotensin system. While renal nerves do not mediate the vasoconstriction of the obstructed kidney, renal nerves modulate vascular tone of the kidney contralateral to UUO.     

肿瘤转移和浸润致输尿管梗阻性肾功能衰竭的临床处理

为提高肿瘤转移和浸润引起的上尿路梗阻性肾功能衰竭的临床诊断和治疗水平，总结了１９８９年８月￣１９９７年７月临床处理３４例的结果。其中原发灶为胃肠道肿瘤１０例，膀胱癌７例，前列腺癌６例，宫颈癌４例，卵巢癌３例，其他肿瘤４例。梗阻部位在输尿管上段９例，经皮尿管下段２５例（７３．５％），其中输尿管膀胱交界处７例（２０．６％）。治疗采用双Ｊ管内引流９例，经皮尿管下段２５例（７３．５％），其中输尿管膀胱交界     

Regulation of renal phosphate reabsorption during development: implications from a new model of growth hormone deficiency

It has been hypothesized that the high rate of renal phosphate (Pi) reabsorption in the immature animal is a consequence of the increased demand for Pi associated with the rapid rate of growth. Although growth hormone (GH) has been proposed to play a role in this process, investigations of the relationship between GH, growth and the renal Pi transport have been hampered by the lack of methods available to specifically alter circulating GH levels. This review summarizes the findings from recent studies using a newly developed peptidic antagonist to GH-releasing factor (GRF-AN) as a method of specifically inhibiting GH release. Systemic injection of GRF-AN was effective in suppressing the pulsatile release of GH, and in significantly attenuating the rate of growth, in both immature and adult rats. However, the inhibition of growth was associated with a reduction in net Pi retention only in immature rats, resulting in a doubling in the urinary excretion of Pi. GRF-AN treatment of immature rats lead to a decrease in the maximum tubular capacity to transport Pi-down to the level seen in adult rats. However, GRF-AN treatment did not alter renal Pi reabsorption in adult rats. We conclude that chronic administration of an antagonist to GRF in rats provides a new model of GH deficiency with which to study the interrelationships between growth, GH and other physiological systems. Furthermore, the findings suggest that the pulsatile release of GH, directly or indirectly, contributes to the high rate of renal Pi reabsorption in young, growing animals and may play a critical role in regulating Pi homeostasis during development.     

The current approach to the assessment of fetal renal function: fact or fiction?

The wide use of ultrasonography during pregnancy has led to the identification of a relatively large number of renal and urinary tract abnormalities, particularly hydronephrosis. Uncertainty, however, exists regarding the indications for surgical intervention. Prominent among the variables currently used to assess fetal renal function and predict the long-term outcome are measurements of urinary concentration of electrolytes and low molecular weight proteins. It has become, therefore, imperative to examine the evidence on which the selection of these variables is based, before they become entrenched in medical practice. The analysis reveals that single measurements of any of these variables is unlikely to be reliable. Sequential measurements, albeit more dependable, are impractical due to the narrow window of opportunity for useful surgical intervention. It is therefore necessary to search for new, innovative approaches aimed at detecting changes in the kidney or urine that reflect the biological response of the developing kidney to injury. Such markers may be represented by renal metabolites or peptides involved in the maintenance of renal function under conditions of stress.     

开放手术治疗肾移植术后输尿管梗阻的技术探讨

目的探讨肾移植术后移植肾输尿管狭窄的开放手术技巧与效果。方法首都医科大学附属北京友谊医院泌尿外科于2019年1月—2020年1月共行166例单肾移植,共发生5例肾移植术后输尿管狭窄,根据梗阻部位的不同采用了不同的开放手术术式进行治疗,回顾性分析这组患者的临床资料及预后。结果5例患者中,男性3例,女性2例,平均年龄42.6岁。其中2例患者原发病为Ⅱ型糖尿病,3例患者为肾小球肾炎。输尿管梗阻确诊的平均时间为肾移植术后143.8 d,行开放手术平均时间为肾移植术后209.8 d,确诊梗阻时平均血肌酐水平为271.94μmol/L。所有患者均因出现移植肾积水合并血肌酐进行性升高经影像学检查确诊,首先采取内支架或经皮肾造瘘紧急挽救肾功能。待肾功能恢复稳定后,根据梗阻段位置,3例患者行移植输尿管-膀胱再吻合术,1例患者行原输尿管-移植肾输尿管端端吻合术,1例患者行膀胱皮瓣翻转代输尿管术。5例患者开放手术平均时间为2.6 h,术中平均出血量为32 ml。开放手术后,5例患者均预后良好,开放手术后平均血清肌酐恢复至111.5μmol/L,尿量正常,无外科并发症发生。随访半年后,5例患者均未再发生输尿管梗阻。结论移植肾输尿管梗阻是肾移植术后常见外科并发症之一,腔内治疗中远期效果有限,根据不同梗阻部位选择不同术式进行开放手术,是治疗移植肾输尿管狭窄的有效方案。     

Acute renal failure due to obstruction in Burkitt lymphoma

 Acute renal failure in Burkitt lymphoma is commonly the result of tumor lysis syndrome. We present a 15-year-old boy who developed hypertension, seizures, and acute renal failure due to extrinsic compression of the bladder and ureters by a large retrovesical Burkitt lymphoma. The causes of acute renal failure in Burkitt lymphoma and the incidence of acute urinary obstruction in this disease are reviewed. Received: 18 May 1998 / Revised: 30 June 1998 / Accepted: 1 July 1998     

急诊输尿管镜碎石取石术治疗输尿管中下段结石并肾绞痛

目的探讨急诊输尿管镜碎石取石术治疗输尿管中下段结石并肾绞痛的临床应用价值。方法回顾分析我院2006年1月至2008年12月行急诊输尿管镜下碎石取石手术治疗输尿管结石并肾绞痛的患者临床资料,共137例,其中男78例,女59例,平均年龄38±9岁。中段11例,下段126例。结果 130例患者一次取石成功,成功率94.9%(130/137);7例未成功,其中2例术中发现结石已排入膀胱,5例进镜失败,术后行体外冲击波碎石术(ESWL),2个月内复查结石均排净。结论急诊行输尿管镜下碎石取石术治疗输尿管中下段结石并肾绞痛是一安全有效选择。     

Ureteral obstruction in the neonatal guinea pig: Interaction of sympathetic nerves and angiotensin

The contribution of sympathetic nerves to the hemodynamic effects of unilateral ureteral obstruction (UUO) was investigated in the neonatal guinea pig. The left ureter was partially constricted (or sham-operated) at birth, and sympathetic innervation was inhibited by guanethidine and compared with saline vehicle-treated animals. At 15–20 days of age, blood presure, cardiac output, total vascular resistance (TVR), renal blood flow, and renal vascular resistance (RVR) were determined before and after infusion of enalapril. UUO reduced cardiac output, increased TVR, and increased RVR of the ipsilateral kidney, whereas guanethidine treatment had no additional effects. Enalapril decreased RVR only in obstructed kidneys and not in intact opposite kidneys of animals with UUO. This was not affected by guanethidine administration. In contrast, enalapril decreased RVR only in guanethidine-treated (but not saline-treated) sham-operated guinea pigs. Therefore, UUO increases angiotensin-dependent vascular tone of the ipsilateral kidney independent of renal innervation. However, UUO decreases angiotensin-mediated vascular tone of the contralateral kidney, an effect unmasked by sympathectomy.     

Transient urethral obstruction predisposes to ascending pyelonephritis and tubulo-interstitial disease: studies in rats

Chronic tubulo-interstitial disease, an important cause of end-stage renal disease, often results from the combined effects of a disturbed urinary outflow tract and urinary tract infection. Acute unilateral ureteral obstruction in rats rapidly induces foci of medullary necrosis, confined to the region of the papilla and fornices. This injury may provide a nidus for bacterial invasion and may invoke reactive and regenerative changes, ultimately leading to chronic pyelonephritis and tubulo-interstitial nephropathy. To explore this possibility, adult rats underwent renal morphological evaluation 2–7 days following transient 24-h unilateral ureteral obstruction. In some experiments the bladder was inoculated with bacteria (10⁸–10⁹ cfu/ml Escherichia coli in 0.5 ml) after release of ureteral obstruction, with subsequent cultures obtained from the pelvis of both kidneys and from the urinary bladder. Morphologic evaluation of perfusion-fixed kidneys, 2–7 days after the release of 24-h ureteral obstruction disclosed papillary necrosis, urothelial proliferation, marked inner-stripe interstitial expansion, and fibrosis and proximal tubular (S₃) dilatation. The lateral (perihilar region) was predominantly affected, with lesions spreading from the fornices. There was some progression of interstitial fibrosis during the postobstructive time course or following more prolonged ureteral obstruction. By contrast, infection hardly contributed to the tubulointerstitial changes. In rats subjected to infection, cultures were positive in all 15 postobstructive kidneys, as opposed to five contralateral kidneys (P < 0.0001). Viable counts from the postobstructive kidney were also higher than those from the contralateral side (79,000 ± 12,000 vs 2900 ± 1600 cfu/ml, mean ± SEM, P < 0.0001), and were comparable to those obtained from the bladder (77,000 ± 13,000 cfu/ml). We conclude that transient ureteral obstruction predisposes to ascending pyelonephritis and to tubulointerstitial disease. This vulnerability may relate to altered urodynamics and medullary tissue destruction. Received: 28 December 1999 / Accepted: 28 September 2000     

Ureteropelvic junction obstruction: morphological and clinical studies

This study included 27 patients with ureteropelvic (UPJ) obstruction. Both renal parenchyma and the junctional abnormality were examined and correlated with clinical findings. Renal biopsies were categorized into grades 1–4. Those with normal or minimal findings (grade 1 and 2, respectively) had excellent renal function as assessed by radionuclide studies. Those with grade 4 had severe histological abnormalities associated with poor renal function. Grade 3 renal changes were seen in patients whose renal function varied greatly and did not correlate with the extent of the limited histological abnormalities. Although there was great variation in the renal biopsies, glomerulosclerosis was a consistent finding, associated with extracapillary proliferation and periodic acid-Schiff-positive material (? Tamm-Horsfall protein) in the urinary space of glomeruli in 91% (10/11) of grade 3 or 4 renal biopsies. No extracapillary proliferation was seen in grade 1 renal biopsies. The UPJ obstruction area was consistently inflamed and markedly thickened due to varying degrees of perifascicular fibrosis and muscular hypertrophy. Extensive fibrosis with associated muscular atrophy was the most-severe change in this spectrum.     

传统开放手术联合经皮顺行通道内镜微创治疗移植肾输尿管梗阻一例

<正>输尿管梗阻是肾移植术后常见的泌尿系统并发症,病因复杂,若诊治不及时可能会导致移植肾功能丧失,严重影响肾移植受者术后生存质量。2018年3月,南方医科大学珠江医院器官移植科采用传统开放手术联合经皮顺行通道内镜微创手术成功治疗1例肾移植术后并发移植肾输尿管梗阻受者,现报道如下。1病例资料受者男性,50岁。2017年12月20日因"尿毒症"于我院接受公民逝世后器官捐献供肾肾移植手     

肿瘤浸润或转移致输尿管梗阻性肾功能衰竭的处理

目的探讨由于肿瘤浸润或转移至后腹膜压迫输尿管引起的梗阻性肾功能衰竭的处理方法。方法报告25例此种患者的临床资料,原发灶为消化道肿瘤11例,泌尿生殖系肿瘤等13例,原发灶不明1例。采用CT扫描明确输尿管梗阻部位12例,MRU扫描5例,B超检查12例,IVU检查6例;并且明确肿瘤转移与梗阻的关系。采用双J导管内引流9例,输尿管皮肤造瘘10例,肾造瘘术6例。结果15例经治疗后肾功能完全恢复正常,10例肾功能有改善。结论CT扫描和MRU对于梗阻部位定位准确且无创;采用双J导管内引流和造瘘外引流损伤小,简便而效果好。     

Evaluation of complications due to percutaneous renal biopsy: a clinical and angiographic study

Complications due to 173 percutaneous biopsies in 158 patients were evaluated. In 57 of the patients the biopsies were guided by renal angiography, and in this group hematomas were found in 23% of the biopsies, arteriovenous fistulae in 8%, and renal infarction in 6%. No predisposing factors leading to complications were found. A transient increase in serum creatinine concentration was recorded with a maximal value about the fourth to sixth day after the biopsy. Thirteen percent of the biopsies controlled by angiography resulted in permanent kidney lesions, but none of them seemed to be of clinical importance.     

Nephrogenic adenoma associated with cytomegalovirus infection of the ureter in a renal transplant patient: presentation as ureteral obstruction

Nephrogenic adenoma (NA), a rare benign lesion of the urinary tract, is widely accepted to be a metaplastic reaction due to urothelial injury. It mainly occurs in the urinary bladder and rarely in the ureter. Renal transplant recipients are prone to the development of NA. However in those patients, NA was diagnosed exclusively in the bladder. Herein, we present the – to our knowledge – first case of NA involving a transplanted ureter. A 42-year-old female kidney transplant recipient suffered hematuria, oliguria, and acute renal failure and presented with ureteral obstruction and hydronephrosis of the renal transplant. To our surprise, evidence of cytomegalovirus (CMV) infection of the NA was demonstrated using special immunohistochemical staining. The findings in this case raise the possibility that CMV infection, as an irritant of the ureteral epithelium, may be an etiological factor of NA. Received: 5 November 1999 Revised: 7 August 2000 Accepted: 20 November 2000     

Urinary tract infection in the newborn: clinical and radio imaging studies

The objective of this study was to assess clinical characteristics and results of radio imaging studies and compare community-acquired urinary tract infection (UTI) with nosocomial UTI in 301 neonates with UTI consecutively admitted to 28 neonatal units in Spain over 3 years (community-acquired UTI, n = 250; nosocomial UTI, n = 51). UTI was diagnosed in the presence of symptoms of infection together with any colony growth for a single pathogen from urine obtained by suprapubic aspiration, or >or=10(4) CFU/ml for a single pathogen from urine obtained by urethral catheterization. Abnormal renal ultrasound was present in 37.1% of cases (34% in community-acquired UTI and 54.5% in nosocomial UTI, P < 0.01). The voiding cystourethrography (VCUG) showed vesicoureteral reflux (VUR) in 27% of cases (23.8% in community-acquired UTI and 48.6% in nosocomial UTI, P < 0.01). In patients with abnormal renal ultrasound and VUR, renal scan with dimercaptosuccinic acid (DMSA) performed early after UTI revealed cortical defects in 69.5% of cases. However, in patients with abnormal renal ultrasound and normal VCUG, DMSA also revealed cortical defects in 39% of cases. The absence of VUR in neonates with UTI and abnormal renal ultrasound does not exclude the presence of cortical defects suggestive of pyelonephritis.     

Urinary excretion of tubular proteins and the technetium-99m dimercaptosuccinic acid (DMSA) absolute renal uptake in partial ureteral obstruction in rats: a functional evaluation of hydronephrotic kidneys

The aim of this longitudinal study was to evaluate tubular proteinuria in rats with unilateral (UPO) and bilateral (BPO) partial ureteral obstruction with the dimercaptosuccinic acid (DMSA) scan as the gold standard for measuring renal tubular damage. We studied 70 female Wistar rats: 28 animals with UPO, 28 animals with BPO, 7 sham-operated animals, and 7 controls. All animals with obstructed ureters showed renal dilatation on the diethylenetriaminepentaacetic acid DTPA images 1 and 5 weeks postoperatively. One week following UPO and BPO, tubular proteinuria and urinary N-acetyl-beta-d-glucosaminidase (NAG) activity increased (P < 0.01) and the absolute DMSA uptake decreased (P < 0.01). Persistently (week 6) high tubular proteinuria was found in 29% of the animals and was related to severe damage on the DMSA scan (P < 0.01) and to albuminuria (P < 0.05). Renal tubular damage was demonstrated by measuring renal enzymes, tubular proteins, and DMSA uptake after UPO and BPO. Persistent elevated tubular proteinuria was related to severely damaged kidneys. Received: 18 June 1998 / Accepted: 20 October 1998     

Effect of prednisolone on ascending renal infection due to biofilm disease and lower urinary tract obstruction in rats

A model of renal infection due to lower urinary tract obstruction and biofilm disease was constructed for the study of renal scarring by inserting glass beads coated with bacterial biofilm into the bladder of rats and then clamping the urethra. We previously reported the effect of antimicrobial therapy used in combination with the anti-inflammatory agent prednisolone to prevent renal scarring. In this study we investigated the effect of prednisolone on renal scar formation using our new model. Renal scarring could not be prevented in the group in which prednisolone was administered in the period during which the urethra was regularly being clamped. In contrast, scarring was prevented in the group that began to receive prednisolone after the period of clamping had ended. Therefore, in cases of lower urinary tract obstruction prednisolone should only be administered for the prevention of renal scarrring after the obstruction has been resolved.     

In utero exposure to nonsteroidal anti-inflammatory drugs: neonatal renal failure

We report a case of neonatal transient renal failure after maternal ingestion of diclofenac, paracetamol, and nimesulide during pregnancy. The baby girl was delivered at the 33 weeks gestation for complete absence of amniotic fluid. Acute renal failure was present. Urine output started 12 h after birth, increasing to polyuria on day 6, and then decreasing gradually to normal values. Serum creatinine normalized on day 6. Several cases of severe and sometimes irreversible renal problems have been described in neonates exposed to indomethacin, a non-selective cyclooxgenase (COX) inhibitor, during their fetal life. More recently, the use of nimesulide, a selective COX-2 inhibitor, as a tocolytic agent has been advocated. Although it is difficult to ascribe the observed side effects to one specific drug in our patient, using the Naranjo ADR probability scale, renal failure was probably related to nimesulide exposure. Paracetamol is considered safe at therapeutic doses, and there are no reports of prenatal diclofenac toxicity. However, recently there have been some reports of neonatal renal failure associated with maternal nimesulide consumption and probably modulated by genetic factors. Hence, cautious use of nimesulide during pregnancy must be advocated.