An update on metabolic assessment in patients with urinary lithiasis.

PURPOSE: The objective of this study was to evaluate the prevalence of urinary metabolic abnormalities in patients with urolithiasis and their potential risk factors. METHODS: A total of 905 stone patients were evaluated in a prospective trial from February 2000 to January 2012. Inclusion criteria were as follows: history and/or imaging tests confirming at least 2 separate or concurrent stone episodes; creatinine clearance ≥ 60 mL/min; and negative proteinuria and urine culture. Metabolic study consisted of two 24-h urine collections separated by a period of 3 months for dosing Ca, P, uric acid, Na, K, Mg, oxalate, and citrate. Serum levels of Ca, P, uric acid, Na, K, Cl, Mg, creatinine, and glucose were assessed. Urinary pH and urinary acidification tests were also performed. RESULTS: A total of 735 patients were included, with a mean age of the 40 ± 1.0 year; 96.8 % of patients presented diagnosis of one or more urinary metabolic abnormalities. The most prevalent metabolic abnormalities were hypercalciuria (50.8 %), hypomagnesuria (50.1 %), hypocitraturia (35.4 %), and hyperuricosuria (30.7 %). Body weight was significantly higher in patients with hyperuricosuria (81.20 ± 15.67 kg vs. 70.17 ± 14.13 kg, respectively, p = 0.001). Urinary sodium was significantly higher in patients with hypercalciuria than without (246.97 ± 103.9 mEq/24 h vs. 200.31 ± 91.6 mEq/24 h, p = 0.001) and hyperuricosuria compared to without (283.24 ± 107.95 mEq/24 h vs. 198.57 ± 85.3 mEq/24 h, p = 0.001). CONCLUSION: Urinary metabolic disturbances were diagnosed in 96.8 % of patients in the study. These results warrant metabolic study and follow-up in patients with recurrent lithiasis in order to decrease recurrence rate through specific treatments, modification in alimentary, and behavioral habits.

The role of salt abuse on risk for hypercalciuria.

BACKGROUND: Elevated sodium excretion in urine resulting from excessive sodium intake can lead to hypercalciuria and contribute to the formation of urinary stones. The aim of this study was to evaluate salt intake in patients with urinary lithiasis and idiopathic hypercalciuria (IH). METHODS: Between August 2007 and June 2008, 105 lithiasic patients were distributed into 2 groups: Group 1 (n = 55): patients with IH (urinary calcium excretion > 250 mg in women and 300 mg in men with normal serum calcium); Group 2 (n = 50): normocalciuric patients (NC). Inclusion criteria were: age over 18 years, normal renal function (creatinine clearance ≥ 60 ml/min), absent proteinuria and negative urinary culture. Pregnant women, patients with intestinal pathologies, chronic diarrhea or using corticoids were excluded. The protocol of metabolic investigation was based on non-consecutive collection of two 24-hour samples for dosages of: calcium, sodium, uric acid, citrate, oxalate, magnesium and urinary volume. Food intake was evaluated by the three-day dietary record quantitative method, and the Body Mass Index (BMI) was calculated and classified according to the World Health Organization (WHO). Sodium intake was evaluated based on 24-hour urinary sodium excretion. RESULTS: The distribution in both groups as regards mean age (42.11 ± 10.61 vs. 46.14 ± 11.52), weight (77.14 ± 16.03 vs. 75.99 ± 15.80), height (1.64 ± 0.10 vs. 1.64 ± plusorminus 0.08) and BMI (28.78 ± 5.81 vs. 28.07 ± 5.27) was homogeneous. Urinary excretion of calcium (433.33 ± 141.92 vs. 188.93 ± 53.09), sodium (280.08 ± 100.94 vs. 200.44.93 ± 65.81), uric acid (880.63 ± 281.50 vs. 646.74 ± 182.76) and magnesium (88.78 ± 37.53 vs. 64.34 ± 31.84) was significantly higher in the IH group (p < 0.05). There was no statistical difference in calcium intake between the groups, and there was significantly higher salt intake in patients with IH than in NC. CONCLUSIONS: This study showed that salt intake was higher in patients with IH as compared to NC.

Metabolic investigation of patients with staghorn calculus: is it necessary?

OBJECTIVE: To evaluate the prevalence of metabolic disorders in patients with staghorn calculi treated at the Regional Center of Lithiasis Metabolic Studies in central region of Såo Paulo State, Brazil. MATERIALS AND METHODS: Between February 2000 and February 2008, 630 patients with urinary calculi were evaluated in the lithiasis outpatient clinic. Thirty-seven of them had staghorn calculi (35 women and 2 men). The inclusion criteria for the metabolic investigation included the absence of urological manipulation 30 days before the examination, negative urine culture and creatinine clearance > 60 mL/min. The protocol for metabolic investigation consisted of qualitative search for cystinuria. Two non-consecutive 24-hour urine samples collected to measure calcium, phosphorus, uric acid, sodium, potassium, magnesium, oxalate and citrate, and serum calcium levels, phosphorus, uric acid, sodium, potassium, magnesium, chloride, parathormone and urine pH. RESULTS: Among patients with lithiasis, 5.9% (37/630) had staghorn calculus and in 48.6% (18/37) were diagnosed with urinary infection. The females were predominant for 94.5% of cases. The calculi were unilateral in 31 of cases and bilateral in six. Metabolic abnormalities were found in 68.2% of patients with hypercalciuria (64.2%) and hypocitraturia (53.3%) being the most common disorders. CONCLUSIONS: The presence of metabolic disorders in nearly 70% of patients with staghorn calculus reinforces the necessity for evaluation of these patients. The diagnosis and treatment of identified metabolic abnormalities can contribute to the prevention of recurrent staghorn calculi.

Metabolic investigation of patients with staghorn calculus: is it necessary?

Objective: To evaluate the prevalence of metabolic disorders in patients with staghorn calculi treated at the Regional Center of Lithiasis Metabolic Studies in central region of São Paulo State, Brazil. Materials and methods: Between February 2000 and February 2008, 630 patients with urinary calculi were evaluated in the lithiasis outpatient clinic. Thirty-seven of them had staghorn calculi (35 women and 2 men). The inclusion criteria for the metabolic investigation included the absence of urological manipulation 30 days before the examination, negative urine culture and creatinine clearance > 60 mL/min. The protocol for metabolic investigation consisted of qualitative search for cystinuria. Two non-consecutive 24-hour urine samples collected to measure calcium, phosphorus, uric acid, sodium, potassium, magnesium, oxalate and citrate, and serum calcium levels , phosphorus, uric acid, sodium, potassium, magnesium, chloride, parathormone and urine pH. Results: Among patients with lithiasis, 5.9 percent (37/ 630) had staghorn calculus and in 48.6 percent (18/37) were diagnosed with urinary infection. The females were predominant for 94.5 percent of cases. The calculi were unilateral in 31 of cases and bilateral in six. Metabolic abnormalities were found in 68.2 percent of patients with hypercalciuria (64.2 percent) and hypocitraturia (53.3 percent) being the most common disorders. Conclusions: The presence of metabolic disorders in nearly 70 percent of patients with staghorn calculus reinforces the necessity for evaluation of these patients. The diagnosis and treatment of identified metabolic abnormalities can contribute to the prevention of recurrent staghorn calculi.

DNA methylation patterns in bladder cancer and washing cell sediments: a perspective for tumor recurrence detection.

BACKGROUND: Epigenetic alterations are a hallmark of human cancer. In this study, we aimed to investigate whether aberrant DNA methylation of cancer-associated genes is related to urinary bladder cancer recurrence. METHODS: A set of 4 genes, including CDH1 (E-cadherin), SFN (stratifin), RARB (retinoic acid receptor, beta) and RASSF1A (Ras association (RalGDS/AF-6) domain family 1), had their methylation patterns evaluated by MSP (Methylation-Specific Polymerase Chain Reaction) analysis in 49 fresh urinary bladder carcinoma tissues (including 14 cases paired with adjacent normal bladder epithelium, 3 squamous cell carcinomas and 2 adenocarcinomas) and 24 cell sediment samples from bladder washings of patients classified as cancer-free by cytological analysis (control group). A third set of samples included 39 archived tumor fragments and 23 matched washouts from 20 urinary bladder cancer patients in post-surgical monitoring. After genomic DNA isolation and sodium bisulfite modification, methylation patterns were determined and correlated with standard clinic-histopathological parameters. RESULTS: CDH1 and SFN genes were methylated at high frequencies in bladder cancer as well as in paired normal adjacent tissue and exfoliated cells from cancer-free patients. Although no statistically significant differences were found between RARB and RASSF1A methylation and the clinical and histopathological parameters in bladder cancer, a sensitivity of 95% and a specificity of 71% were observed for RARB methylation (Fisher's Exact test (p < 0.0001; OR = 48.89) and, 58% and 17% (p < 0.05; OR = 0.29) for RASSF1A gene, respectively, in relation to the control group. CONCLUSION: Indistinct DNA hypermethylation of CDH1 and SFN genes between tumoral and normal urinary bladder samples suggests that these epigenetic features are not suitable biomarkers for urinary bladder cancer. However, RARB and RASSF1A gene methylation appears to be an initial event in urinary bladder carcinogenesis and should be considered as defining a panel of differentially methylated genes in this neoplasia in order to maximize the diagnostic coverage of epigenetic markers, especially in studies aiming at early recurrence detection.

Late presentation of posterior urethral valve: two case reports.

CONTEXT: Posterior urethral valve (PUV) is a widely known condition affecting males that generally presents prenatally or at birth. PUVs have also been occasionally described in literature in cases diagnosed during adolescence or adulthood. CASE REPORT: This report presents two late PUV cases, one in a teenager and the other in an adult. Both cases had had clinical signs of urinary tract infection and obstructive urinary symptoms. The diagnoses were made by means of voiding cystourethrography and urethrocystoscopy. Endoscopic valve fulguration was the treatment chosen for both. Their follow-up was uneventful.

Late presentation of posterior urethral valve: two case reports / Apresentação tardia de válvula de uretra posterior: relato de dois casos

CONTEXT: Posterior urethral valve (PUV) is a widely known condition affecting males that generally presents prenatally or at birth. PUVs have also been occasionally described in literature in cases diagnosed during adolescence or adulthood. CASE REPORT: This report presents two late PUV cases, one in a teenager and the other in an adult. Both cases had had clinical signs of urinary tract infection and obstructive urinary symptoms. The diagnoses were made by means of voiding cystourethrography and urethrocystoscopy. Endoscopic valve fulguration was the treatment chosen for both. Their follow-up was uneventful.

CONTEXTO: Válvula de uretra posterior (VUP) é uma conhecida malformação congênita urinária, geralmente diagnosticada em exames ultra-sonográficos pré-natais ou ao nascimento. Raramente, esta doença pode ser encontrada em adolescentes e em adultos. RELATO DE CASOS: Este artigo mostra dois casos de VUP, encontrados em um adolescente e em um adulto. Ambos apresentavam sinais clínicos de infecção do trato urinário e sintomas obstrutivos infravesicais. Os diagnósticos foram realizados por uretrocistografia miccional e uretrocistoscopia. Fulguração endoscópica das válvulas foi o tratamento de escolha para ambos os casos. O acompanhamento demonstrou melhora importante dos sintomas após o tratamento.

Estudo do jato urinário intravesical com Doppler colorido em pacientes com e sem refluxo vesicoureteral / Study of the ureterovesical jet by means of color Doppler in patients with and without vesicoureteral reflux

OBJETIVO: O presente estudo teve como objetivo comparar os achados da uretrocistografia miccional com o ultra-som Doppler duplex colorido, em pacientes com suspeita de refluxo vesicoureteral. MATERIAIS E MÉTODOS: A pesquisa foi realizada através do estudo dos ângulos dos jatos urinários intravesicais, nos planos axial e longitudinal. Foi analisada, também, a distância (em centímetros) entre os meatos ureterais. RESULTADOS: Do total de 32 pacientes estudados (com média de idade de 5 anos e 2 meses), 18 pacientes apresentaram refluxo vesicoureteral (10 com refluxo unilateral, sendo 4 no lado direito e 6 no lado esquerdo, e 8 com refluxo bilateral) e 14 pacientes não apresentaram refluxo. Os valores angulares dos jatos urinários intravesicais e as distâncias entre os meatos ureterais foram obtidos para todos os pacientes e foram calculados a média, o desvio-padrão e o coeficiente de variação. CONCLUSÃO: Os dados evidenciaram tendência de que a lateralização do meato ureteral seja sinal de predisposição ao refluxo vesicoureteral. A análise estatística não-paramétrica de Mann-Whitney não evidenciou diferenças significativas (p > 0,05) entre os grupos (ângulos de inclinação dos jatos urinários intravesicais e distância entre os meatos ureterais).

Comportamento do magnésio urinário em pacientes com litíase renal / Urine magnesium in patients with nephrolithiasis

Introdução: O Magnésio é considerado como tendo efeito inibidor na cristalização, nucleação e crescimento do oxalatode cálcio. Diversos estudos têm demonstrado diferentes resultados do manuseio do magnésio pelo néfron. Objetivo: Oobjetivo deste trabalho foi estudar o comportamento do magnésio urinário nos portadores de alterações metabólicas presentesnos pacientes com litíase renal. Pacientes e Métodos: Foram estudados 182 pacientes com história de litíaserecorrente, clearance de creatinina ³ 60ml/min, ausência de proteinúria e urocultura negativa. O protocolo consistiu emdosagens urinárias de 24h de Ca, P, AcU, Na, K, Mg, Ox e Ci e dosagens séricas de glicemia, Ca, P, AcU, Na, K, Cl,Mg, U, Cr; índice CaU/MgU em urina 24h; pH urinário. Resultados: Preencheram os critérios de inclusão 158 pacientes.Destes, 151 apresentaram pelo menos uma alteração metabólica, sendo: hipercalciúria (74,0), hipocitratúria (37,3),hiperoxalúria (24,1), hipomagnesúria (21), hiperuricosúria (20,2), hiperparatireoidismo primário (1,8), secundário(0,6) e ATR (0,6). O índice CaU/MgU estava significativamente maior (p< 0,0001) nos pacientes hipercalciúricos.Conclusões: A hipomagnesúria isolada não se correlacionou com nenhuma alteração metabólica, porém o índiceCaU/MgU estava significativamente aumentado nas hipercalciúrias em comparação aos não hipercalciúricos. A partirdestes dados sugerimos que o magnésio deva ser monitorado nestes pacientes; sua reposição poderia ser mais umaopção terapêutica na prevenção de novos cálculos de cálcio.

Metabolic assessment in patients with urinary lithiasis.

INTRODUCTION: Metabolic investigation in patients with urinary lithiasis is very important for preventing recurrence of disease. The objective of this work was to diagnose and to determine the prevalence of metabolic disorders, to assess the quality of the water consumed and volume of diuresis as potential risk factors for this pathology. PATIENTS AND METHODS: We studied 182 patients older than 12 years. We included patients with history and/or imaging tests confirming at least 2 stones, with creatinine clearance > or = 60 mL/min and negative urine culture. The protocol consisted in the collection of 2, 24-hour urine samples, for dosing Ca, P, uric acid, Na, K, Mg, Ox and Ci, glycemia and serum levels of Ca, P, Uric acid, Na, K, Cl, Mg, U and Cr, urinary pH and urinary acidification test. RESULTS: 158 patients fulfilled the inclusion criteria. Among these, 151 (95.5%) presented metabolic changes, with 94 (62.2%) presenting isolated metabolic change and 57 (37.8%) had mixed changes. The main disorders detected were hypercalciuria (74%), hypocitraturia (37.3%), hyperoxaluria (24.1%), hypomagnesuria (21%), hyperuricosuria (20.2%), primary hyperparathyroidism (1.8%), secondary hyperparathyroidism (0.6%) and renal tubular acidosis (0.6). CONCLUSION: Metabolic change was diagnosed in 95.5% of patients. These results warrant the metabolic study and follow-up in patients with recurrent lithiasis in order to decrease the recurrence rate through specific treatments, modification in alimentary and behavioral habits.

Single testicular metastasis mimicking primary testicular neoplasm: a rare manifestation of prostate cancer.

The incidence of secondary testicular tumors ranges from 0.02 to 2.5% among autopsies in general. With the exception of leukemias and lymphomas, prostate cancer is the most common primary site. It is diagnosed in autopsies or incidentally, following therapeutic orchiectomies in more advanced stages of the disease. In the present report, we show a case of testicular metastasis derived from prostate neoplasm whose clinical presentation as a single metastasis was similar to a primary testicular neoplasm. The diagnosis was evidenced after orchiectomy by histological examination and immunohistochemical tests.

Metabolic assessment in patients with urinary lithiasis

INTRODUCTION: Metabolic investigation in patients with urinary lithiasis is very important for preventing recurrence of disease. The objective of this work was to diagnose and to determine the prevalence of metabolic disorders, to assess the quality of the water consumed and volume of diuresis as potential risk factors for this pathology. PATIENTS AND METHODS: We studied 182 patients older than 12 years. We included patients with history and/or imaging tests confirming at least 2 stones, with creatinine clearance > 60 mL/min and negative urine culture. The protocol consisted in the collection of 2, 24-hour urine samples, for dosing Ca, P, uric acid, Na, K, Mg, Ox and Ci, glycemia and serum levels of Ca, P, Uric acid, Na, K, Cl, Mg, U and Cr, urinary pH and urinary acidification test. RESULTS: 158 patients fulfilled the inclusion criteria. Among these, 151 (95.5 percent) presented metabolic changes, with 94 (62.2 percent) presenting isolated metabolic change and 57 (37.8 percent) had mixed changes. The main disorders detected were hypercalciuria (74 percent), hypocitraturia (37.3 percent), hyperoxaluria (24.1 percent), hypomagnesuria (21 percent), hyperuricosuria (20.2 percent), primary hyperparathyroidism (1.8 percent) secondary hyperparathyroidism (0.6 percent) and renal tubular acidosis (0.6). CONCLUSION: Metabolic change was diagnosed in 95.5 percent of patients. These results warrant the metabolic study and follow-up in patients with recurrent lithiasis in order to decrease the recurrence rate through specific treatments, modification in alimentary and behavioral habits.

Single testicular metastasis mimicking primary testicular neoplasm: a rare manifestation of prostate cancer

The incidence of secondary testicular tumors ranges from 0.02 to 2.5 percent among autopsies in general. With the exception of leukemias and lymphomas, prostate cancer is the most common primary site. It is diagnosed in autopsies or incidentally, following therapeutic orchiectomies in more advanced stages of the disease. In the present report, we show a case of testicular metastasis derived from prostate neoplasm whose clinical presentation as a single metastasis was similar to a primary testicular neoplasm. The diagnosis was evidenced after orchiectomy by histological examination and immunohistochemical tests.

Oxibutinina intravesical / Intravesical oxybutynin

Os autores apresentam o caso de uma criança com bexiga neurogênica hiper-reflexa secundária a mielomeningocele, tratada inicialmente com oxibutinina por via oral e cateterismo intermitente, com bons resultados durante 18 meses. Após este período, a paciente desenvolveu náuseas e constipaçäo intestinal severa. A substituiçäo da medicaçäo oral pela via intravesical obteve bons resultados terapêuticos, com o desaparecimento dos efeitos colaterais

Fístula uretero-vaginal: análise de cinco casos / Ureterovaginal fistula: reviewed five cases

A fístula uretero-vaginal (FUV) pode ocorrer em conseqüência a intervençöes cirúrgicas da cavidade pélvica. No período de janeiro de 1975 a outubro de 1990 foram estudados cinco casos de fístula uretero-vaginal. A idade média foi de 44 anos, variando de 28 a 66 anos. A lesåo ureteral foi bilateral em um caso (20 por cento) e unilateral em quatro (80 por cento), sendo três (75 por cento) à direita. Em todos os casos havia perda urinária contínua com micçöes intermitentes. A urografia excretora e a pielografia ascendente foram exames decisivos na confirmaçåo diagnóstica. O intervalo entre o diagnóstico e o tratamento variou de três a 28 semanas. A correçåo da FUV foi realizada por reimplante uretero-vesical em cinco ureteres e por anastomoose uretero-ureteral em um caso. Os resultados foram bons em quatro pacientes, com um seguimento de 12 meses. O único caso de insucesso ocorreu em uma paciente submetida previamente a tratamento radioterápico

Expression of beta-human chorionic gonadotropin (ß-hCG) in non-trophoblastic elements of transitional cell carcinoma of the bladder: possible relationship with the prognosis

Transitional cell carcinoma (TCC) of the bladder is a neoplasm with variability in its clinical behavior. Although there are several studies correlating stage and ABO isoantigen expression with invasiveness, there is no single predictor factor to assess the potential invasiveness, especially in the low grade, non-invasive TCC. In the present study we evaluated the correlation of histological gradeplus stage and the expression of beta human chorionic gonadotropin (ß-hCG); in 100 cases of TCC, with the clinical behavior. These features were correlated with tumor progression in patients with at least two years of follow up. We observed more aggressiveness in G4 group (high grade and invasive) (93 per cents had tumor progression) when comapared to G1 group (low grade and superficial) (11 per cents had tumor progression). However in 25.5 per cents of the TCC cases (groups G2: low grade and invasive and G3: high grade and superficial) the clincial behavior was intermediate, showing some limitation in using grading and staging only, as predictive factor. There was an expression of ß-hCG in 21.4 per cents of the cases in up to 25 per cents of the tumor cells without any trophoblastic morphology. These ß-hCG producing TCC had a strong correlation with aggressiveness: 39.1 per cents and 12.8 per cents of the TCC expressed ß-hCG with and without tumor progression, respectively

Estudo polarográfico da isquemia renal no cäo: açäo do manitol / Polarographic study of renal ischaemia in dog: manitol effect

Um estudo polarográfico do oxigênio renal, no córtex e na medula, antes e após isquemia renal foi realizado em 27 caes anestesiados, implantando-se 2 eletrodos de platino no rim esquerdo. A pesquisa teve como objetivo o estudo do fenômeno "no-reflow" após 2 e 3 horas de isquemia renal sob proteçao do manitol. A polarografia detectou o fenômeno "no-reflow" e demonstrou o efeito protetor do manitol na isquemia renal.

Estudo polarográfico do oxigênio renal no cäo: açäo do manitol / Polarographic study of renal oxygen in dog: mannitol action

Um estudo polarográfico do oxigênio renal, no córtex e na medula, foi efetuado em 19 cäes anestesiados, implantando-se 2 eletrodos de platina no rim esquerdo. A pesquisa teve como objetivos o estudo do método polarográfico e da açäo do manitol. Foram estudados os atributos: intensidade basal (ib), intensidade máxima (imax) e intervalo (I). A pesqusia constou de 2 grupos: grupo 1 (controle) e grupo 2 (administraçäo endovenosa de manitol). Os valores de ib e imax encontrados no córtex foram menores do que os da medula. Näo houve diferença significante nos atributos estudados entre o início e o fim da experiência (grupo 1). No grupo 2 o manitol determinou uma diminuiçäo de ib e um aumento de I

Avaliaçäo do oxigênio renal pelo método polarográfico na obstruçäo ureteral aguda: estudo experimental no cäo / Evaluation of renal oxygen by polarographics methods in the ureteral obstruction: experimental study in dog

Com o objetivo de se avaliar, no rim, a repercussäo da obstruçäo ureteral unilateral aguda e da atuaçäo do manitol durante e após a obstruçäo, realizou-se, em 18 cäes anestesiados, um estudo polafrográfico de oxigênio no córtex dos rins direito e esquerdo (obstruído), abordados por laparotomia. Foram estudados os seguintes atributos obtidos nas curvas polarográficas: Intervalo (I) em segundos, intensidade basal (ib) e intensidade máxima (imax), obtidos em uA e posteriormente transformados em pressäo parcial de oxigênio (mmHg) e denominados, respectivamente, pressäo basal (Pb) e pressäo máxima (Pmax). Foram também estudados pressäo ureteral (PU) em mm de Hg, pressäo arterial (PA) em cm de Hg, pressäo venosa central (PVC) em cm de H2O e diurese (ml). A pesquisa constou de dois grupos experimentais: Grupo 1 (G1) - Realizou-se obstruçäo ureteral, tendo-se administrado, após desobstruçäo, manitol a 20 por cento (15 ml/kg/peso) por via endovenosa. Grupo 2 (G2) - Realizou-se obstruçäo ureteral, com administraçäo de manitol a 20 por cento (7 ml/kg/peso) por via endovenosa, na vigência da mesma. Os atributos foram estudados nos seguintes momentos: M1 - 30 minutos pós implante dos eletrodos. Obstruçäo ureter esquerdo. M2 - 60 minutos pós obstruçäo do ureter. Manitol no G2. M3 - 90 minutos pós obstruçäo do ureter. M4 - 120 minutos pós obstruçäo do ureter. M5 - 180 minutos pós obstruçäo do ureter. M6 - 30 minutos pós desobstruçäo do ureter. Manitol no G1. M7 - 60 minutos pós desobstruçäo do ureter. Mp - durante estudo da pressäo ureteral, imediatamente após a obstruçäo ureteral. Ao término do experimento, os rins foram retirados e examinados macroscopicamente. A presente pesquisa permitiu as conclusöes a seguir enumeradas: 1. A polarografia se mostrou um método adequado no estudo do oxigênio renal. 2. Os eletrodos polarográficos, tal como foram manufaturados, mostraram-se com características adequadas quanto à sensibilidade e fixaçäo no rim. 3. A metodologia empregada na obstruçäo do ureter foi eficiente em produzir aumento da pressäo ureteral. 4. A obstruçäo ureteral (Grupo 1) näo provocou alteraçöes estatisticamente significativas, nos atributos polarográficos. 5. O manitol, pós desobstruçäo (Grupo 1), provocou aumento näo significativo da Pb e Pmax. 6. O manitol, na fase de obstruçäo (Grupo 2), provocou uma diminuiçäo da Pmax (significativa) e da Pb (näo significativa).