Combined Retrograde Flexible Ureteroscopic Lithotripsy with Holmium YAG Laser for Renal Calculi Associated with Ipsilateral Ureteral Stones

Purpose: The purpose of this study was to evaluate the effectiveness of combined ureteroscopic holmium YAG lithotripsy for renal calculi associated with ipsilateral ureteral stones. Materials and Methods: Between August 2002 and March 2007, retrograde flexible ureteroscopic stone treatment was attempted in 351 cases. Indication for treatment was concurrent symptomatic ureteral stones in 63 patients (group I). Additional operative time and perioperative complication rates were compared to a group of 39 patients submitted to ureteroscopic treatment for ureteral calculi exclusively (group II). Results: Mean ureteral stone size was 8.0 +/- 2.6 mm and 8.1 +/- 3.4 mm for groups I and II, respectively. Mean operative time for group I was 67.9 +/- 29.5 minutes and for group 2 was 49.3 +/- 13.2 minutes (p < 0.001). Flexible ureteroscopic therapy for renal calculi increased 18 minutes in the mean operative time. The overall complication rate was 3.1% and 2.5% for groups I and II, respectively (p = 0.87). Mean renal stone size was 10.7 +/- 6.4 mm, overall stone free rate in group I was 81%. However, considering only patients with renal stones smaller than 15 mm, the stone free rate was 88%. Successful treatment occurred in 81% of patients presenting lower pole stones, but only 76% of patients with multiple renal stones became stone free. As expected, stone free rate showed a significant negative correlation with renal stone size (p = 0.03; r = -0.36). Logistic regression model indicated an independent association of renal stones smaller than 15 mm and stone free rate (OR = 13.5; p = 0.01). Conclusion: Combined ureteroscopic treatment for ureteral and ipsilateral renal calculi is a safe and attractive option for patients presenting for symptomatic ureteral stone and ipsilateral renal calculi smaller than 15 mm.

Comparison of videolaparoscopic versus open surgery for benign renal diseases in children

Introduction: Laparoscopic nephrectomy in children has become a reasonable alternative to open nephrectomy and has replaced open surgery for many renal diseases. The purpose of our study is to evaluate transperitoneal videolaparoscopic procedures in renal benign diseases in comparison to an open surgery approach. Patients and methods: 34 children aged between 17 days and 15 years old (mean 6.14) were divided into two groups in order to be submitted to nephrectomy. The first one underwent transperitoneal videolaparoscopic nephrectomy and was composed by 21 patients aged from 2 months to 15 years (mean 7.42), from which 12 were females and 9 males. The second group was submitted to open nephrectomy and was composed by 13 patients aged from 17 days to 11 years (mean 3.91), 6 females and 7 males. The groups were compared regarding anesthesic time, operative time, length of hospital stay, postoperative pain and time of reintroduction of oral intake. Short and long term complications were also evaluated. Statistical analysis was performed by Student t-test with the level of significance set at P < 0.05. The study was previously approved by the Committee on Ethics in Research of our institution. Results: Significant statistical difference was observed only for the variable length of hospital stay. No laparoscopy group case was converted to open surgery. There was no immediate or late complication. Blood loss was negligible and no transfusion was required. Conclusions: In our experience, transperitoneal videolaparoscopic nephrectomy has similar results to open nephrectomy, except for time of hospitalization. (C) 2009 AEU. Published by Elsevier Espana, S.L. All rights reserved.

Percutaneous ultrasound-guided renal biopsy in children - safety, efficacy, indications and renal pathology findings: 14-year Brazilian university hospital

Introduction: Pediatric percutaneous renal biopsy (Bx) is a routine procedure in pediatric nephrology to obtain renal tissues for histological study. We evaluated the safety, efficacy, indications and renal findings of this procedure at a tertiary care pediatric university hospital and compared our findings with the literature. Methods: Retrospective study based on medical records from January 1993 to June 2006. Results: In the study period, 305 Bx were performed in 262 patients, 127 (48.5%) male, aged 9.8 +/- 4.2 years. A 16-gauge needle was utilized in 56/305 Bx, an 18-gauge needle in 252/305 Bx (82.6%). 56.1% Bx were performed under sedation plus local anesthesia, 43.9% under general anesthesia. The number of punctures per Bx was 3.1 +/- 1.3. Minor complications occurred in 8.6% procedures. The 16-gauge needle caused a higher frequency of renal hematomas (p = 0.05). The number of glomeruli per puncture was >= 5 in 96.7% and >= 7 in 92%. Glomeruli number per puncture and frequency of complications were not different according to the type of anesthesia used. A renal pathology diagnosis was achieved in 93.1% Bx. The main indications of Bx were nephrotic syndrome (NS), lupus nephritis (LN) and hematuria (HE). The diagnosis of minimal change disease (MCD) (61.3%), class V (35.6%) and IgA nephropathy (26.3%) predominated in NS, LN and HE patients, respectively. Conclusion: Pediatric real-time ultrasound-guided percutaneous renal biopsy was safe and effective. The main clinical indications for Bx were NS and LN, the predominant renal pathology diagnoses were MCD and class V LN.

Histological and functional renal alterations caused by Bothrops alternatus snake venom: Expression and activity of Na(+)/K(+)-ATPase

Background: Acute renal failure is a serious complication of human envenoming by Bothrops snakes. The ion pump Na(+)/K(+)-ATPase has an important role in renal tubule function, where it modulates sodium reabsorption and homeostasis of the extracellular compartment. Here, we investigated the morphological and functional renal alterations and changes in Na(+)/K(+)-ATPase expression and activity in rats injected with Bothrops alternatus snake venom. Methods: Male Wistar rats were injected with venom (0.8 mg/kg, iv.) and renal function was assessed 6.24, 48 and 72 h and 7 days post-venom. The rats were then killed and renal Na(+)/K(+)-ATPase activity was assayed based on phosphate release from ATP; gene and protein expressions were assessed by real time PCR and immunofluorescence microscopy, respectively. Results: Venom caused lobulation of the capillary tufts, dilation of Bowman`s capsular space. F-actin disruption in Bowman`s capsule and renal tubule brush border, and deposition of collagen around glomeruli and proximal tubules that persisted seven days after envenoming. Enhanced sodium and potassium excretion, reduced proximal sodium reabsorption, and proteinuria were observed 6 h post-venom, followed by a transient decrease in the glomerular filtration rate. Gene and protein expressions of the Na(+)/K(+)-ATPase alpha(1) subunit were increased 6 h post-venom, whereas Na(+)/K(+)-ATPase activity increased 6 h and 24 h post-venom. Conclusions: Bothrops alternatus venom caused marked morphological and functional renal alterations with enhanced Na(+)/K(+)-ATPase expression and activity in the early phase of renal damage. General significance: Enhanced Na(+)/K(+)-ATPase activity in the early hours after envenoming may attenuate the renal dysfunction associated with venom-induced damage. (C) 2011 Elsevier B.V. All rights reserved.

Essential regulatory elements for NHE3 gene transcription in renal proximal tubule cells

The objectives of the present study were to identify the cis-elements of the promoter absolutely required for the efficient rat NHE3 gene transcription and to locate positive and negative regulatory elements in the 5’-flanking sequence (5’FS), which might modulate the gene expression in proximal tubules, and to compare this result to those reported for intestinal cell lines. We analyzed the promoter activity of different 5’FS segments of the rat NHE3 gene, in the OKP renal proximal tubule cell line by measuring the activity of the reporter gene luciferase. Because the segment spanning the first 157 bp of 5’FS was the most active it was studied in more detail by sequential deletions, point mutations, and gel shift assays. The essential elements for gene transcription are in the region -85 to -33, where we can identify consensual binding sites for Sp1 and EGR-1, which are relevant to NHE3 gene basal transcription. Although a low level of transcription is still possible when the first 25 bp of the 5’FS are used as promoter, efficient transcription only occurs with 44 bp of 5’FS. There are negative regulatory elements in the segments spanning -1196 to -889 and -467 to -152, and positive enhancers between -889 and -479 bp of 5’FS. Transcription factors in the OKP cell nuclear extract efficiently bound to DNA elements of rat NHE3 promoter as demonstrated by gel shift assays, suggesting a high level of similarity between transcription factors of both species, including Sp1 and EGR-1.

Reduced cortical renal GLUT1 expression induced by angiotensin-converting enzyme inhibition in diabetic spontaneously hypertensive rats

Diabetes in spontaneously hypertensive rats is associated with cortical renal GLUT1 and GLUT2 overexpression. Our objective was to evaluate the effect of the angiotensin-converting enzyme blockade on cortical renal GLUT1 and GLUT2 expression, urinary albumin and urinary TGF-β1. Streptozotocin, 50 mg/kg, or citrate buffer (N = 16) was administered as a single injection into the tail vein in adult spontaneously hypertensive rats (~260 g). Thirty days later, these diabetic spontaneously hypertensive rats received ramipril by gavage: 0.01 mg·kg-1·day-1 (D0.01, N = 14), 1 mg·kg-1·day-1 (D1, N = 9) or water (D, N = 11) for 15 days. Albumin and TGF-β1 (24-h urine), direct arterial pressure, renal tissue angiotensin-converting enzyme activity (fluorometric assay), and GLUT1 and GLUT2 protein levels (Western blot, renal cortex) were determined. Glycemia and glycosuria were higher (P < 0.05) in the diabetic rats compared with controls, but similar between the diabetic groups. Diabetes in spontaneously hypertensive rats lowered renal tissue angiotensin-converting enzyme activity (40%), which was reduced further when higher ramipril doses were used. Diabetes associated with hypertension raised GLUT1 by 28% (P < 0.0001) and GLUT2 by 76% (P = 0.01), and both doses of ramipril equally reduced cortical GLUT1 (D vs D1 and vs D0.01, P ≤ 0.001). GLUT2 levels were reduced in D0.01 (P < 0.05 vs D). Diabetes increased urinary albumin and TGF-β1 urinary excretion, but the 15-day ramipril treatment (with either dose) did not reduce them. In conclusion, ramipril is effective in lowering renal tissue angiotensin-converting enzyme activity, as well as blocking cortical GLUT1 overexpression, which may be beneficial in arresting the development of diabetic nephropathy.

Influência do bloqueador de receptor de angiotensina (Losartana potássica) na função renal e pressão arterial em cães GRMD

A distrofia muscular de Duchenne (DMD) é uma alteração neuromuscular caracterizada por contínua necrose muscular e degeneração, com eventual fibrose e infiltração por tecido adiposo. O aumento progressivo da fibrose intersticial no músculo impede a migração das células miogênicas, necessárias para a formação muscular. O modelo canino constitui-se nas melhores fenocópias da doença em humanos, quando comparados com outros modelos animais com distrofia. O tratamento antifibrose de pacientes DMD, tendo como alvo os mediadores da citocina, TGF-beta, e o tratamento com antiinflamatórios, podem limitar a degeneração muscular e contribuir para a melhora do curso da doença. O presente estudo teve como objetivo observar os possíveis efeitos adversos na fisiologia renal, por meio de avaliação bioquímica sanguínea e da pressão arterial, verificando a viabilidade do uso do Losartan (um inibidor de TGF-beta) nos cães afetados pela distrofia muscular. Foram utilizados quatro cães adultos, sendo dois machos e duas fêmeas. Utilizou-se a dose de 50mg de Losartan, administrada via oral, uma vez ao dia. Os exames clínicos, bem como alterações na função renal, o nível do potássio sérico e a pressão arterial não evidenciaram reação adversa durante todo o período do experimento. O uso de Losartan, por um período de 9 semanas, mostrou-se como uma terapia segura para o tratamento antifibrótico em cães adultos, não afetando a função renal ou pressão arterial dos animais.

Ultra-sonografia do fígado, aparelho renal e reprodutivo da jibóia (Boa constrictor)

Atualmente os animais silvestres têm despertado o interesse particular na criação domestica. Na medicina de animais selvagens, os exames ultra-sonográficos podem ser considerados como ferramenta para diagnosticar e prevenir doenças. Deste modo, realizou-se um estudo em 20 jibóias (Boa constrictor), a fim de caracterizar a morfologia e aparência ultra-sonográfica das estruturas presentes da cavidade celomática desses animais. Ultra-sonograficamente, o fígado apresentou-se variando de hipoecóica a levemente hiperecogênica, com margens ecogênicas e ecotextura homogênea em toda sua extensão. Os rins mostraram formato elipsóide, com cápsula fina, regular e hiperecóica. Os folículos ovarianos apresentaram formato ovóide, margens finas, regulares e discretamente hiperecóicas. As estruturas do sistema reprodutor do macho não foram evidenciadas com precisão, devido a sua ecogenicidade similar em relação às estruturas adjacentes e pela presença do "corpo gorduroso" localizado nessa região. A ultra-sonografia da cavidade celomática em jibóias demonstrou ser uma técnica rápida e de fácil acesso, permitindo identificar a morfologia, sintopia e aparência ultra-sonográfica de estruturas como o fígado, rins e de folículos vitelogênicos nas fêmeas.

Morfologia e desenvolvimento ultraestrutural do sistema renal de embriões bovinos com idade gestacional entre 10 e 50 dias

O presente estudo teve como objetivo descrever o desenvolvimento dos sistemas renais de bovinos durante o período embrionário compreendido entre 10 e 50 dias. Embriões bovinos coletados em frigorífico foram fotografados e medidos utilizando-se o método Crow-Rump (CR) para estimar a idade gestacional. Os embriões destinados à miscroscopia óptica foram fixados em solução de Bouin para a avaliação do desenvolvimento do sistema renal, assim como suas estruturas. Alguns embriões também foram fixados em Glutaraldeído 2,5% e destinados à microscopia eletrônica de transmissão para o estudo ultraestrutural das células do sistema renal. Embriões entre o 14° e o 15° dia de desenvolvimento (E14-15) não apresentaram pronefro, mas apresentaram mesonefro, assim como indícios morfológicos que indicam sua atividade funcional. O mesonefro apresentou, no interior de suas células tubulares, inúmeras mitocôndrias e interdigitações, indicando uma alta atividade de transporte iônico. O metanefro, ou rim definitivo, iniciou seu desenvolvimento em E23-24. Os achados emonstram que a involução do mesonefro acontece simultaneamente com a diferenciação metanefrogênica. Em E45-46, já iniciando a fase fetal, o metanefro possuiu unidades filtradoras (néfrons), com seus respectivos glomérulos, túbulos contorcidos proximais e distais e alça de Henle. Nessa fase, o rim ainda não apresenta lobação externa.

Avaliação da técnica de arteriografia renal guiada por fluoroscopia em suínos

The fluoroscopy-guided renal arteriography was evaluated in order to be used as an auxiliary method in investigations and as a way to experimentally induce kidney diseases in swine. The technique was effective to obtain sharp images as well as to determine the area of renal irrigation. Despite its easiness, trained professionals are required to perform it.

Classificação em estágios da doença renal crônica em cães e gatos: abordagem clínica, laboratorial e terapêutica

Foi proposta uma revisão das terminologias empregadas para a descrição das alterações renais e também sugerida uma classificação em estágios para a doença renal crônica à semelhança da medicina humana pela IRIS (International Renal Interest Society). Essa classificação considera os estágios da doença de acordo com o tempo de evolução e a presença de marcadores de lesão renal. O objetivo principal é auxiliar no estabelecimento do diagnóstico, do prognóstico e da terapia adequada conforme cada estágio e, assim, retardar a perda da função dos rins e a evolução da doença renal e, dessa forma, propiciar melhor qualidade de vida ao paciente.

Endoscopic Ultrasound Facilitates Histological Diagnosis of Renal Cell Cancer

Over two-thirds of renal masses noted incidentally on abdominal CT scans performed for nonurological indications are most likely renal cell carcinoma (RCC). The prognosis in these instances is often quite favorable, as early diagnosis offers the best hope of a complete cure. We report the identification of a RCC incidentally at endoscopic ultrasound (EUS) while an earlier CT scan of abdomen was negative. The mass was biopsied resulting in a histological confirmation of RCC and successful surgical resection.

Comparison of the effects of carbon dioxide and helium pneumoperitoneum on renal function

Background and Purpose: Carbon dioxide pneumoperitoneum is associated with significant hypercarbia and acidosis. The aim of this study is to evaluate the effects of carbon dioxide and helium pneumoperitoneum on renal function. Materials and Methods: Thirty adult dogs were put randomly into one of three groups ( n = 10 animals each): group A - pneumoperitoneum not performed; group B - CO2 pneumoperitoneum; and group C - helium pneumoperitoneum. The groups were analyzed with consideration given to body weight, hematologic values, hemodynamic parameters ( heart rate, mean arterial pressure, central venous pressure, cardiac output, stroke volume, systemic vascular resistance, pulmonary vascular resistance, left cardiac work index, cardiac index, mean pulmonary artery pressure, and pulmonary capillary wedge pressure), and renal function ( plasma renin activity, urinary output, creatinine clearance, and sodium excretory fraction). Results: An accentuated decrease in urinary output was observed during pneumoperitoneum in groups B and C compared to the control group. In groups B and C, creatinine clearance declined significantly during pneumoperitoneum in comparison to group A, but after deflation a faster recovery of glomerular filtration was noticed for group C, and a significant increase in sodium excretory fraction was seen for group B. On the other hand, in comparison to the control group, group B had a significant increase in plasma renin activity, with late recovery of glomerular function. Conclusion: Helium ameliorates renal alterations when used for pneumoperitoneum, and it might be used for patients with compromised renal function who have to undergo laparoscopic surgery.

Evaluation of Cadaveric Renal Vein Lengths and Their Extension Loss with Three Types of Ligature and Section

Background and Purpose: The right kidney has been less frequently used in live donor nephrectomy, because of the shorter length of the right renal vein (RRV) that is associated with technical difficulties and higher rates of venous thrombosis. In live open donor or deceased donor transplant nephrectomy, an additional cuff of the inferior vena cava is usually removed, but this is a more difficult and risky maneuver in laparoscopic nephrectomy. For this reason, laparoscopic right nephrectomy (LRN) for renal transplantation (RT) is not frequently performed in most medical institutions. We evaluate the difference between RRV and left renal vein (LRV) lengths in cadavers, as harvested for RT by three clamping methods. Our objective was to obtain information that could clarify when LRN for RT should be encouraged or avoided with regard to conventional surgery. Materials and Methods: Ninety adult fresh unfrozen cadavers were randomly divided into three groups of 30, according to the clamping device used: Satinsky, stapler, and Hem-o-lok clip. The abdominal viscera were removed through a median xyphopubic incision, and the veins were measured on the bench. Two lateral limits were used: The renal hilum and the tangential line of the renal poles. As for medial limits, the inferior vena cava or the laparoscopic clipping device on the RRV were used on the right side, while on the LRV, the medial border of the emergence of the adrenal vein was considered. After section of the renal vein, a slight traction of the extremity was applied for the measurement. All measurements were obtained three times using a metallic millimetric ruler, and the arithmetic mean was considered. The chi-square, one-way analysis of variance, and paired t tests were used for statistical analysis. Statistical significance was accepted at P <= 0.05. Results: The groups of cadavers were homogeneous in demographic characteristics. Regardless of the clamping method and considering the useful length of the LRV, the RRV was statistically smaller. The evaluation of the vein length did not depend on the lateral limit considered. Independent of the clamping method, on both sides, the lengths after the vein section were larger than before the section, a fact attributed to traction. Use of a stapler and a single Hem-o-lok presented the same waste of vein length on the right side. On average, the RRV was 13.7% shorter than the LRV. Conclusions: With the wide acceptance of laparoscopic live donor nephrectomy, the length difference between the veins of both kidneys is an important issue, and the right kidney is therefore used less than the left, compared with conventional surgery. This article represents the first step to quantify the anatomic length of renal veins in different situations. Certainly, more imagenologic or surgical studies should be carried out before decisions can be made for better selection of patients for LRN.

Determination of the Most Efficient Temperature for Radiofrequency Ablation of Renal Cells: A Prospective Study in Dogs

Background and Purpose: Radiofrequency (RF) ablation of renal tumors is a major technique for tumor cell destruction while preserving healthy renal parenchyma. There is no consensus in the literature regarding the optimal temperature, impedance, and time for RF application for effective cell destruction. This study investigated two variables while keeping time unchanged: Temperature for RF cell destruction and tissue impedance in dog kidneys. Materials and Methods: Sixteen dogs had renal punctures through videolaparoscopy for RF interstitial tissue ablation. A RF generator was applied for 10 minutes to the dog's kidney at different target temperatures: 80 degrees C, 90 degrees C, and 100 degrees C. On postoperative day14, the animals were sacrificed and nephrectomized. All lesions were macroscopically and microscopically examined. The bioelectrical impedance was evaluated at three different temperatures. Results: Renal injuries were wider and deeper at 90 degrees C (P < 0.001), and they were similar at 80 degrees C and 100 degrees C. The bioelectrical impedance was lower at 90 degrees C than at the temperatures of 80 degrees C and 100 degrees C (P < 0.001). Viable cells in the RF ablation tissue area were not found in the microscopic examination. Conclusion: The most effective cell destruction in terms of width and depth was achieved at 90 degrees C, which was also the optimal temperature for tissue impedance. RF ablation of renal cells eliminated all viable cells.