Study of the association between the BMP4 gene and congenital anomalies of the kidney and urinary tract / Estudo da associação entre o gene BMP-4 e anomalias congênitas do rim e trato urinário

OBJECTIVE: To determine the frequency of different phenotypes for congenital anomalies of the kidney and urinary tract (CAKUT) in a Brazilian sample, and to evaluate the association between the CAKUT phenotypes and the BMP4 gene. METHODS: In this study, 457 Brazilian individuals were analyzed in an attempt to establish the association between the BMP4 gene and the CAKUT diagnosis. A case-control sample was genotyped for three BMP4 gene polymorphisms. RESULTS: Association data was established with CAKUT sample as a whole and with the three most important CAKUT phenotypes: multicystic dysplastic kidney disease (MDK), ureteropelvic junction obstruction (UPJO) and vesicoureteral reflux (VUR). When the sample was segregated in these three phenotypes, associations between the BMP4 gene were observed with UPJO and with MDK. Conversely, VUR was not associated to the polymorphisms of the BMP4 gene. CONCLUSIONS: The present data suggest that Brazilian individuals with polymorphisms of the BMP4 gene have a higher risk to develop CAKUT, especially the malformations related to nephrogenesis and initial branching such as MDK and UPJO. Conversely, VUR appeared not to be related to BMP4 gene. .

OBJETIVO: Determinar a frequência de diferentes fenótipos de anomalias congênitas do rim e trato urinário (CAKUT) em uma amostra brasileira e avaliar a associação entre os CAKUT e o gene BMP-4. MÉTODOS: Neste estudo, analisamos 457 indivíduos brasileiros em uma tentativa de estabelecera associação entre o gene BMP-4 e o diagnóstico de CAKUT. As amostras de caso e de controle foram genotipadas em busca de três polimorfismos do gene BMP-4. RESULTADOS: Os dados de associação foram estabelecidos com a amostra de CAKUT como um todo e com os três fenótipos de CAKUT mais importantes: rim displásico multicístico (RDM), obstrução da junção ureteropélvica (UPJO) e refluxo vesico-ureteral (VUR). Quando a amostra foi separada nesses três fenótipos, encontramos associações entre o gene BMP-4 com UPJO e com RDM. Por outro lado, o VUR não foi associado aos polimorfismos do gene BMP-4. CONCLUSÕES: Esses dados sugerem que os indivíduos brasileiros com polimorfismos do gene BMP-4 apresentam maior risco de desenvolver CAKUT, principalmente as malformações relacionadas a nefrogênese e ramificação inicial, como RDM e UPJO. Por outro lado, o VUR parece não estar relacionado ao gene BMP-4. .

Multicystic dysplastic kidney - A need for conservative and long term approach.

Objective. We retrospectively studied our cases of Multicystic Dysplastic Kidney (MCDK). The review was aimed at identifying the pattern of the disease in Indian Scenario and the required management thereof. Methods. We studied the clinical, radiological and nuclear scan findings of 22 patients with unilateral MCDK. They were diagnosed and/or treated in our unit from 1999 to 2007. The diagnosis was achieved by Ultrasound and further confirmed by DMSA scans. Other ancillary investigations like Micturating cystourethrogram were done if indicated. These patients were followed and followup investigations consisted of renal ultrasound, blood pressure measurement, and urinalysis and blood biochemistry. Results. A total of 22 patients (18 boys and 4 girls) with unilateral MCDK were investigated and followed for a mean period of 41 months. MCDK was detected on antenatal ultrasound only in 12(55%) and postnatally in 10(45%) babies. Mean age for postnatal diagnosis was 20 months. Follow up ultrasound revealed complete involution of MCDK in 3 patients and partial regression in 11 patients. The size of dysplastic kidney was unchanged in 4 patients and a further 4 patients underwent nephrectomy. Indications of nephrectomy were parental anxiety in 2, hypertension in 1 and palpable mass in 1. Conclusion. Large proportion (45%) of patients in presented series are diagnosed post natally contrary to western world where more than 80% are diagnosed antenatally. Uncomplicated isolated MCDK carry good prognosis with nephrectomy required in only a few patients. Association with other urological anomalies in ipsilateral/contralateral genitourinary tract is important to identify as they have worse outcome in terms of ultimate renal function. All patients with simple/complex unilateral MCDK should be advised long term follow up for the possible development of hypertension and/or hyper infiltration injury.