Complications after bladder augmentation in children

PURPOSE : Bladder augmentation is an effective surgical procedure for increasing bladder capacity and reducing pressure on the urinary system. It is indicated for patients with anomalies such as spina bifida, myelomeningocele, urethral valve and bladder exstrophy, who progress with low tolerance of medication. CASES : This was a retrospective study conducted on pediatric patients submitted to bladder augmentation from 2000 to 2011. RESULTS : 34 patients aged 4 to 17 years were submitted to bladder augmentation, 30 of them with an ileal loop and 4 with a ureter.A continent urinary shunt was performed in 16 patients, the Mitrofanoff conduit was associated in 15, and the Macedo technique was used in one. Mean follow-up was 34.35 months (1 to 122 months). Mean creatinine was 1.5 ng/ml (0.4 to 7.5 ng/ml) preoperatively and 1.78 ng/ml postoperatively. Three patients required a renal transplant during follow-up. There was improvement or resolution of vesicoureteral reflux in 83.5% of the kidneys on the right and in 75% on the left. Bladder capacity increased, on average, from 152.5 ml to 410 ml. The main complications were vesical lithiasis in 3 patients and conduit perforation in one. CONCLUSION : Bladder augmentation showed good results in this series, preserving renal function in most of the patients.

Postnatal evaluation of intrauterine hydronephrosis due to ureteropelvic junction obstruction / Avaliação pós-natal de hidronefrose intra-uterina por estenose da junção ureteropiélica

PURPOSE: Fetal hydronephrosis is a frequent finding due to advances in prenatal ultrasonography. The definition of fetal and neonatal urinary tract obstruction is a very difficult task requiring confirmation of reduced renal function and hydronephrosis. In this study we followed a series of consecutive patients with intrauterine hydronephrosis that persisted during post-natal life. METHODS: 116 newborns with antenatal hydronephrosis diagnosed by ultrasound and submitted to a specific post-natal evaluative protocol with a follow-up period of 6 years. RESULTS: In 45 (38.8%) of 116 patients, ureteropelvic junction (UPJ) obstruction was confirmed and surgical correction of the UPJ obstruction was done in 19 patients. From 26 children who were initially submitted to non-surgical treatment, only 6 (23%) needed a surgical approach during follow up. Overall analysis showed that surgery was performed in 25 patients with UPJ obstruction, and the others 20 patients were kept under clinical observation, since normal renal function was confirmed by scintigraphy scans. CONCLUSION: Fetal hydronephrosis due to UPJ obstruction deserves careful postnatal evaluation. UPJ obstruction is the most frequent anomaly and its surgical treatment has very precise indications. The evaluative protocol was useful in identify patients that could be followed-up with a non-surgical approach.

OBJETIVO: Com a ampla utilização dos exames ultrassonográficos na avaliação pré-natal, é frequente o diagnóstico da hidronefrose fetal. A definição de obstrução do trato urinário no periodo pós-natal necessita da confirmação de redução da função renal além da hidronefrose. Neste estudo, acompanhamos uma série de pacientes consecutivos com hidronefrose intra-útero que persistiu no periodo pós-natal. MÉTODOS: 116 recém-nascidos com hidronefrose pré-natal diagnosticada pela ultrassonografia foram submetidos a protocolo específico de avaliação e companhados pelo periodo de 06 anos. RESULTADOS: Em 46 (38,8%) dos 116 pacientes foi confirmado o diagnóstico de estenose da junção ureteropiélica (JUP). Conforme os resultados do protocolo aplicado a correção cirúrgica da estenose da JUP foi realizada em 19 pacientes. Das 26 crianças encaminhadas inicialmente para observação clínica, apenas 6 (23%) necessitaram cirurgia durante o seguimento ambulatorial. Na análise geral, o procedimento cirúrgico para correção da estenose da JUP foi indicado em 25 pacientes. Nas outras 20 crianças não houve necessidade da realização da cirurgia. CONCLUSÃO: a hidronefrose fetal requer cuidadosa avaliação pós-natal. A estenose da junção pielo-ureteral é a anomalia mais frequente como causa da hidronefrose, e sua correção cirúrgica tem indicações precisas. O protocolo aplicado foi útil em diferenciar pacientes que não necessitaram cirurgia para tratamento da estenose da JUP.

Expression of VEGF and collagen using a latex biomembrane as bladder replacement in rabbits

OBJECTIVE: To investigate the VEGF expression and collagen deposition using a latex biomembrane as bladder replacement in rabbits. MATERIALS AND METHODS: After partial cystectomy, a patch of a non-vulcanized latex biomembrane (2 x 2 cm) was sewn to the bladder of rabbits with 5/0 monofilament polydioxanone sulfate sutures in a watertight manner. Groups of 5 animals were killed at 15, 45 and 90 days after surgery and the bladder was removed. Sections of 5µm were cut and stained with picrosirius-red in order to estimate the amount of extracellular matrix in the graft. To confirm the presence of VEGF in tissues, protein expression was determined by immunohistochemistry. RESULTS: No death, urinary leakage or graft extrusion occurred in any group. All bladders showed a spherical shape. A progressive reduction in the amount of collagen occurred in the graft area and was negatively and linearly correlated with time (p < 0.001). VEGF expression was higher in grafted areas when compared to controls at 15 and 45 days after surgery and decreased with time (p < 0.001). CONCLUSION: The latex biomembrane as a matrix for partial bladder replacement in rabbits promotes temporary collagen deposition and stimulates the angiogenic process.

Lovastatin protects mithochondrial and renal function in kidney ischemia-reperfusion in rats / Lovastatina protege a função renal e mitocondrial na isquemia/reperfusão renal em ratos

PURPOSE: To investigate the effect of lovastatin on renal ischemia followed by reperfusion. METHODS: Thirty one Wistar rats submitted to left renal ischemia for 60 minutes followed by contralateral nephrectomy were divided into two groups: A (n =17, control, no treatment), and B (n=14, lovastatin 15 mg/kg/day p.o. ten days before ischemia). The animals were sacrificed at the end of ischemia, after 24 hours and at seven days after reperfusion. Survival, serum urea and creatinine levels and renal mitochondrial function were evaluated. RESULTS: Mortality was 29.4% in group A and 0.7% in group B. Urea and creatinine levels were increased in both groups, but the values were significantly lower in group B. Mitochondrial function showed decoupling in 83.4% of group A, as opposed to 38.4/% of group B. CONCLUSIONS: The result shows a protective action of renal function by lovastatin administered before ischemia/reperfusion. Since most of the mitochondrial fraction presented membranes with the ability to maintain ATP production in group B, stabilization of the mitochondrial membrane should be considered as part of the protective action of lovastatin on renal function in ischemia/reperfusion.

OBJETIVO: Investigar a ação da lovastatina na isquemia renal seguida de reperfusão. MÉTODOS: Trinta e um ratos Wistar submetidos à isquemia renal esquerda durante 60 minutos, seguida da nefrectomia contralateral, foram distribuídos em dois grupos: A (n=17, controle, sem tratamento) e B (n=14, recebendo 15 mg/Kg/dia de lovastatina via oral), durante os dez dias que antecederam a isquemia. Os animais foram mortos ao final da isquemia, e com 24 horas e sete dias após a reperfusão. Foram avaliadas a sobrevida, os valores séricos de uréia e creatinina e a função mitocondrial renal. RESULTADOS: A mortalidade foi 29,4% no grupo A e 0,7% no grupo B. Os níveis de uréia e creatinina elevaram-se nos dois grupos, mas foram significativamente menores no grupo B. No grupo A a função mitocondrial renal ficou desacoplada em 83,4% dos ensaios, enquanto que no grupo B isto ocorreu em apenas 38,4% dos ensaios. CONCLUSÕES: Os resultados mostram que a administração de lovastatina antes do episódio de isquemia protege a função renal. No grupo B, como a maior parte da fração mitocondrial isolada apresentou função acoplada à produção de ATP, deve-se também considerar a estabilização da membrana mitocondrial como parte da ação protetora da lovastatina na função renal durante isquemia e reperfusão.

Chronic partial urethral obstruction in female rats: description of an experimental model and initial results / Obstrução parcial uretral crônica em ratos: descrição de um modelo experimental e resultados iniciais

PURPOSE: To develop an experimental model of infravesical urinary obstruction in female rats. METHODS: After median caudal laparotomy, the urethra of 14 female rats was delicately separated from the vagina and loosely wrapped with cellophane tape measuring 0.4 x 1.0 cm. The animals were evaluated 4 (n=7) and 8 (n=7) weeks later. Five additional control animals were only subjected to separation of the urethra and vagina and monitored for 12 weeks. RESULTS: After four weeks, three rats presented vesical dilation associated with discrete ureteral ectasis in 2 animals, with the third presenting discrete hydronephrosis in one kidney. After eight weeks, five rats (71.4 percent) presented vesical distension with bilateral ureterohydronephrosis. No significant changes (p>0.05) in serum urea or creatinine occurred in any group compared to preoperative values. CONCLUSION: We present here an inexpensive and simple method for the slow induction of urethral obstruction in adult female rats, with the development of progressive vesical hypertrophy and ureterohydronephrosis, which may be used as an experimental model for the study of different aspects of obstructive nephropathy.

OBJETIVO: Desenvolver modelo experimental de obstrução urinária infravesical em ratas. MÉTODOS: Após laparotomia caudal mediana, as uretras de 14 ratas foram delicadamente separadas da vagina e frouxamente envoltas com fita de celofane medindo 0.4 x 1.0 cm. Os animais foram avaliados 4 (n=7) e 8 (n=7) semanas depois. Cinco animais adicionais (controle) foram submetidos apenas à separação da uretra e da vagina e monitoradas por 12 semanas. RESULTADOS: Após quatro semanas, três ratas apresentaram dilatação vesical associada a discreta ectasia ureteral em 2 animais, com o terceiro apresentando discreta hidronefrose em um rim. Após oito semanas, cinco ratas (71.4 por cento) apresentaram distensão vesical com ureterohidronefrose bilateral. Não ocorreram alterações significativas (p>0.05) nos valores de uréia ou creatinina em qualquer grupo, comparado com valores pré-operatórios. CONCLUSÃO: Apresentamos aqui um método barato e simples para a indução lenta de obstrução uretral em ratas adultas, com desenvolvimento progressivo de hipertrofia vesical e ureterohidronefrose, podendo ser utilizado como modelo experimental para estudo de diferentes aspectos da nefropatia obstrutiva.