Unilateral Multicystic Dysplastic Kidney Research Articles

Unilateral multicystic dysplastic kidney: long term outcomes

Aims: To report the long term follow up of children with antenatally detected unilateral multicystic dysplastic kidney (MCDK) with documentation of complications, involution rate with time, and renal function at...

Mutations in Uroplakin IIIA Are a Rare Cause of Renal Hypodysplasia in Humans

Renal hypodysplasia, characterized by a decrease in nephron number, small overall kidney size, and maldeveloped renal tissue, is a leading cause of chronic renal failure in young children. Familial clustering and renal hypodysplasia phenotypes observed in transgenic animal models suggest a genetic contribution. Uroplakin IIIa (encoded by UPIIIA) is an integral membrane protein present in urothelial plaques, and the murine UPIIIa knockout is associated with urothelial anomalies and vesicoureteral reflux. De novo UPIIIA mutations recently were identified in 4 of 17 patients with severe bilateral renal adysplasia. To evaluate the overall role of UPIIIA in human renal hypodysplasia pathogenesis, we performed UPIIIA mutation analysis in a cohort of 170 pediatric patients affected by severe unilateral or bilateral renal hypodysplasia. Eighty-one patients were affected by bilateral nonobstructive renal hypodysplasia; of these, 61 were without vesicoureteral reflux. Eighty-four patients presented with unilateral nonobstructive renal hypodysplasia, including 24 patients with unilateral multicystic dysplastic kidneys. Family history was positive in 11%. Mutation analysis showed 2 heterozygous mutations not observed in 200 race-matched control chromosomes. In only 1 family was distribution of the UPIIIA mutation consistent with a disease-causing effect. This de novo missense mutation (Gly202Asp) was identified in a patient with unilateral multicystic dysplastic kidneys. The second (intronically located) mutation appeared unlikely to be disease causing because it did not segregate with an obvious disease phenotype in the affected family. Our results indicate that de novo mutations in UPIIIA can be involved in defective early kidney development, but probably constitute only a rare cause of human renal hypodysplasia in a minor subset of individuals.

Predictive Factors of Ultrasonographic Involution of Prenatally Detected Multicystic Dysplastic Kidney

OBJECTIVE To evaluate possible predictive factors of involution on ultrasonography (US) or disappearance of a prenatally detected multicystic dysplastic kidney (MCDK). PATIENTS AND METHODS Forty-five children with unilateral MCDK detected by prenatal ultrasonography between 1989 and 2002 were analysed. All patients except one had 99mTc isotopic scintigraphy to confirm the absence of renal function in the MCDK. All children were managed conservatively with follow-up visits every 6 months, with US 6-monthly during the first 2 years of life and yearly thereafter. Survival was analysed using the Kaplan-Meier method to evaluate the involution of the MCDK, with differences between subgroups assessed using the two-sided log-rank test. Cox's regression model was applied for the multivariate analysis. RESULTS The mean (range) follow-up was 50 (12–167) months; in all, 279 ultrasonograms were taken, the mean (range) number per patient being 6 (3–10). US showed partial involution of the MCDK in 30 (67%) cases and complete involution in nine (20%). The absolute MCDK length remained almost unchanged in six children (13%). Univariate analysis showed that four variables were possibly associated with complete involution of the MCDK (gender, impalpable kidney, renal length at admission using two thresholds, 62 and 78 mm). After adjusting by Cox's model only a renal length at diagnosis of <62 mm remained associated with complete involution (relative risk 8, 95% confidence interval 0.98–68; P = 0.05). CONCLUSION These results suggest that only a renal length of <62 mm on initial US was predictive of complete involution of the MCDK during the follow-up.

575: Is Follow Up Necessary in Patients with Unilateral Multicystic Dysplastic Kidney?

You have accessJournal of UrologyModerated Poster, Monday, May 22, 2006, 8:00 - 10:00 am1 Apr 2006575: Is Follow Up Necessary in Patients with Unilateral Multicystic Dysplastic Kidney? Bulent Onal, and Barry A. Kogan Bulent OnalBulent Onal More articles by this author , and Barry A. KoganBarry A. Kogan More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(18)32821-0AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "575: Is Follow Up Necessary in Patients with Unilateral Multicystic Dysplastic Kidney?." The Journal of Urology, 175(4S), p. 186 © 2016 by American Urological AssociationFiguresReferencesRelatedDetails Volume 175Issue 4SApril 2006Page: 186 Advertisement Copyright & Permissions© 2016 by American Urological AssociationMetricsAuthor Information Bulent Onal More articles by this author Barry A. Kogan More articles by this author Expand All Advertisement Loading ...

Does the multicystic dysplastic kidney really involute? The role of the retroperitoneoscopic approach

Objective To assess the role of video-assisted retroperitoneoscopy in the follow up of multicystic dysplastic kidney (MCDK) that has involuted – disappeared? – on serial renal ultrasonography (US). Patients and methods Prospectively, we performed a retroperitoneoscopy in 14 patients, nine girls and five boys, with unilateral MCDK that had involuted on serial US. MCDK was diagnosed in utero (80%) and confirmed postnatally by US and Tc99m dimercaptosuccinic acid radionuclide scan. Follow up US examinations were performed at 1 month, 5 months and 12 months in the first year of life and every 6 months from then on. US showed complete involution at a mean age of 13 months (range 5–18 months). Retroperitoneoscopy was then indicated, at a mean age of 23 months (range 8–24 months), to confirm the disappearance of the kidney dysplastic remnant. Results Retroperitoneoscopy detected persistence of anomalous kidney tissue in 100% of cases. The mean length of the renal remnant was 2 cm (range 1–3.5 cm). Two cases showed a pelvic ectopic location that was not detected by US before involution. The remnant was removed during the same procedure. Anatomo-pathological findings were found to be compatible with dysplastic renal tissue. There were no intra- or postoperative complications. All patients had a mean length of stay of less than 24 h. Conclusions Complete resolution on US does not mean disappearance of MCDK, as US does not detect renal dysplastic remnants after cyst involution has occurred. The retroperitoneoscopic approach to the renal and pelvic area is a minimally invasive, safe and effective procedure to diagnose and treat the renal dysplastic remnant in US-involuted MCDK.

Unilateral multicystic dysplastic kidney

A 4-year-old girl was referred to Great Ormond Street Hospital for Children NHS Trust, London, UK, for evaluation of solitary kidney. She had no symptoms. There were no dysmorphic features; a surgical scar was noted in the left flank. Her blood pressure was 97/65 mmHg. Hemoglobin was 12.6 g/dl, white blood cell count 8.2 x 10(9)/l and platelet count 334 x 10(9)/l. Plasma sodium was 144 mmol/l, potassium 3.6 mmol/l, creatinine 42 mmol/l (0.47 mg/dl), total calcium 2.35 mmol/l, magnesium 0.75 mmol/l, albumin 4.3 g/dl and parathyroid hormone 4.8 pmol/l (all normal). Plasma phosphate was raised at 2.28 mmol/l, but subsequent values were normal. Dipstick urinalysis revealed no blood, protein or glucose. Urinary microscopy revealed no red or white cells, and sparse coliforms (10(3)-10(4)/ml) on culture were interpreted as contaminants. Urinary albumin/creatinine ratio was 0.7 mg/mmol (normal range 0.5-3.3), but N-acetyl-beta-D-glucosaminidase/creatinine was elevated at 75 U/ml (normal 2-22). Ultrasonography (US) showed no renal tissue on the left, with a right kidney of normal shape and echogenicity: its length was 8.2 cm (50th centile for age, 7.1 cm); there was no renal tract dilation, and the bladder was normal with minimal postmicturition residual.

Routine Voiding Cystourethrography Is of No Value in Neonates With Unilateral Multicystic Dysplastic Kidney

Routine Voiding Cystourethrography Is of No Value in Neonates With Unilateral Multicystic Dysplastic Kidney

Conservative management of multicystic dysplastic kidney: clinical course and ultrasound outcome

The aim of this study was to describe the clinical course and ultrasound outcome of prenatally detected multicystic dysplastic kidney. Fifty-three children with unilateral multicystic dysplastic kidney detected by prenatal ultrasound between 1989 and 2004 were included in the analysis. All children were submitted to conservative management with follow-up visits every six months. Follow-up ultrasound examinations were performed at six-month intervals during the first two years of life and yearly thereafter. The following clinical parameters were evaluated: blood pressure, urinary tract infection, renal function, and growth. The following ultrasound parameters were evaluated: involution of multicystic dysplastic kidney and contralateral renal growth. The mean follow-up time was 68 months. Two children presented hypertension during follow-up and five had urinary tract infection (only one with recurrent episodes). There was no malignant degeneration of multicystic dysplastic kidney. A total of 334 ultrasound scans were analyzed. US scan demonstrated involution of the multicystic dysplastic kidney in 48 (90%) cases, including complete involution in nine (17%). The involution rate was faster in the first 30 months of life. There was progressive compensatory renal hypertrophy of the contralateral renal unit; the rate of growth was greater in the first 24 months of life. The results of prolonged follow-up of children with conservatively managed multicystic dysplastic kidney suggest that clinical approach is safe, the incidence of complications is small, and that there is a clear tendency for multicystic dysplastic kidney to decrease in size. Our data also suggest that the involution rate of multicystic dysplastic kidney as well as the growth of the contralateral kidney is greater in the first 24 months of life.

Tratamento conservador do rim displásico multicístico: curso clínico e ultra-sonográfico

OBJETIVO: Descrever o curso clínico e a evolução ultra-sonográfica de pacientes com rim displásico multicístico tratados conservadoramente. MÉTODOS: Foram incluídas no estudo 53 crianças com rim displásico multicístico unilateral diagnosticado pela ultra-sonografia fetal entre 1989 e 2004. Todos os pacientes foram submetidos a protocolo sistemático, incluindo tratamento conservador e exames clínicos, laboratoriais e ultra-sonográficos periódicos. Os exames foram realizados com periodicidade de 6 meses, nos 2 primeiros anos, e anualmente, após esse período. No curso clínico, foram avaliados: pressão arterial, infecção do trato urinário, função renal e crescimento dos pacientes. Na evolução ecográfica, foram avaliados a involução do rim displásico multicístico e o crescimento do rim contralateral. RESULTADOS: O tempo médio de seguimento foi de 68 meses. Dois pacientes apresentaram hipertensão arterial no seguimento. Cinco tiveram infecção urinária (apenas um com episódios repetidos). Não houve degeneração maligna do rim displásico multicístico. Foram realizados 334 exames ultra-sonográficos seriados. Houve involução do rim displásico multicístico em 90% dos casos, sendo que nove (17%) desapareceram. O ritmo de involução foi maior nos 30 primeiros meses de vida. Houve progressiva hipertrofia compensatória do rim contralateral, sendo o ritmo mais intenso nos 2 primeiros anos de vida. CONCLUSÃO: Os resultados do acompanhamento prospectivo de crianças portadoras de rim displásico multicístico tratadas conservadoramente sugerem que a conduta clínica é segura, a incidência de complicações é mínima e há uma nítida tendência de involução ultra-sonográfica da unidade renal afetada. Os dados sugerem, ainda, que o ritmo de involução do rim displásico multicístico, assim como da hipertrofia compensatória do rim contralateral, sejam maiores nos 2 primeiros anos de vida.

A familial case of multicystic dysplastic kidney

A familial case of multicystic dysplastic kidney (MCDK) is described. The proband is a one-year-old boy with left MCDK, and his father was also revealed to have unilateral MCDK. The mother had two abortions; the second pregnancy was terminated because of bilateral MCDK of the fetus (Potter anomaly). The two patients and the aborted male fetus did not have any malformations except for MCDK. Thus in this family MCDK occurs as an isolated phenomenon in three individuals within two generations, presumably as a result of autosomal dominant inheritance.

Routine Voiding Cystourethrography is of no Value in Neonates with Unilateral Multicystic Dysplastic Kidney

To determine if two successive ultrasound examinations could rule out the presence of clinically significant contralateral anomalies in neonates with multicystic dysplastic kidney (MCDK), thereby avoiding unnecessary voiding cystourethrography (VCUG). We followed 76 newborn infants with antenatally discovered MCDK. Two successive neonatal renal ultrasound examinations were performed, one within the first week and one at around 1 month of life. VCUG and isotopic studies were performed in all infants. Urologic anomalies of the contralateral kidney were present in 19 of 76 children (25%): vesicoureteral reflux (VUR) in 16 (21%), ureteropelvic junction obstruction in 2 (3%), and renal duplex kidney in 1 (1%). Sixty-one infants (80% of total) had normal contralateral urinary tract on the 2 successive neonatal renal ultrasound scans. Among them, 4 of 61 (7%) infants presented with low-grade VUR on VCUG that had resolved spontaneously before 2 years of age. The sensitivity, specificity, positive predictive value, and negative predictive value of two successive ultrasound scans in the neonatal period to predict contralateral urological anomalies on VCUG were 75%, 95%, 80%, and 93%, respectively. In infants with antenatally diagnosed MCDK, two successive normal neonatal renal ultrasound scans will rule out clinically significant contralateral anomalies, thereby rendering the need for a neonatal VCUG unnecessary.

Laparoscopic nephrectomy for unilateral multicystic dysplastic kidney in children

The contemporary management of children with unilateral multicystic dysplastic kidney remains controversial. With the potential risks of hypertension, infection, and malignant transformation of the dysplastic kidney, conservative management necessitates long-term review with frequent ultrasound scans, urine analyses, and blood pressure checks. Operative management has traditionally used open nephrectomy with its associated patient morbidity. The introduction of laparoscopic procedures has allowed the development of techniques that reduce patient morbidity, hospital stay, and analgesia requirement. This article reports a series of 13 children who underwent elective laparoscopic nephrectomy for unilateral multicystic dysplastic kidney and discusses the advantages this procedure has to offer for their management.

Predictive factors of ultrasonographic involution of prenatally detected multicystic dysplastic kidney

To evaluate possible predictive factors of involution on ultrasonography (US) or disappearance of a prenatally detected multicystic dysplastic kidney (MCDK). Forty-five children with unilateral MCDK detected by prenatal ultrasonography between 1989 and 2002 were analysed. All patients except one had (99m)Tc isotopic scintigraphy to confirm the absence of renal function in the MCDK. All children were managed conservatively with follow-up visits every 6 months, with US 6-monthly during the first 2 years of life and yearly thereafter. Survival was analysed using the Kaplan-Meier method to evaluate the involution of the MCDK, with differences between subgroups assessed using the two-sided log-rank test. Cox's regression model was applied for the multivariate analysis. The mean (range) follow-up was 50 (12-167) months; in all, 279 ultrasonograms were taken, the mean (range) number per patient being 6 (3-10). US showed partial involution of the MCDK in 30 (67%) cases and complete involution in nine (20%). The absolute MCDK length remained almost unchanged in six children (13%). Univariate analysis showed that four variables were possibly associated with complete involution of the MCDK (gender, impalpable kidney, renal length at admission using two thresholds, 62 and 78 mm). After adjusting by Cox's model only a renal length at diagnosis of <62 mm remained associated with complete involution (relative risk 8, 95% confidence interval 0.98-68; P = 0.05). These results suggest that only a renal length of <62 mm on initial US was predictive of complete involution of the MCDK during the follow-up.

Prenatal Detection of Congenital Renal Malformations by Fetal Ultrasonographic Examination: An Analysis of 709,030 Births in 12 European Countries

The study was performed to evaluate the prevalence of prenatal ultrasound diagnoses for renal anomalies in 20 registries of 12 European countries, and to compare the different prenatal scanning policies. Standardized data were acquired from 709,030 livebirths, stillbirths, and induced abortions during the study period of 2.5 years and transmitted for central analysis. At least one renal malformation was diagnosed in 1130 infants and fetuses. Prenatal diagnosis (PD) was given in 81.8% of all cases, 29% of these pregnancies were terminated. The highest detection rate was reported for unilateral multicystic dysplastic kidneys with 97% (102/105). An early diagnosis was documented for exstrophy of bladder at a mean gestational age of 18.5 weeks. Dilatations of the upper urinary tract were seen late in pregnancy at 28.3 weeks. Terminations of pregnancies (TOP) were performed in 67% (58/86) of the detected bilateral renal agenesis/dysgenesis, but only 4% of the unilateral multicystic dysplastic renal malformations (4/102). In about 1/3 of the cases, renal malformations are within the category of associated malformations, which include multiple non-syndromal malformations, chromosomal aberrations, and non-chromosomal syndromes. Renal malformations were detected in 2/3 of the associated category by the first prenatal ultrasound scan. Detection rates vary in the different countries of the European community due to diverse policies, ethical, and religious background. Countries with no routine ultrasound show the lowest rates in detection, and termination of pregnancy. Prenatally detected renal malformations should result in a careful examination for further anomalies. Prenatal ultrasound fulfills the needs of screening examinations and is a good tool in detecting lethal and severe renal malformations.

Nephrectomy for multicystic dysplastic kidneys: a new therapeutic option

We read with interest the article entitled “Natural history of multicystic kidney conservatively managed: a prospective study” by Rabelo et al. [1] in this journal and would like to describe our current approach for the management of multicystic dysplastic kidneys (MCDK) with laparoscopic nephrectomy. Rabelo et al. [1] postulated that the long-term conservative management of children with unilateral MCDK is a safe option because its natural history is benign with a small number of complications and a low rate of contralateral kidney abnormalities. According to their calculation, it takes nearly 10 years (122 months) for the MCDK to involute completely. Recently, however, management has been based on cost-effectiveness [2]. In addition, it should be noted that long-term follow-up of the seemingly asymptomatic child does not only result in significant clinic non-attendance but also induces long-term parental anxiety [3]. Recent advances in laparoscopic nephrectomy have enabled us to apply this procedure to infants [4]. The benefit of this less invasive approach is based on improved cosmetic results and shorter convalescence compared with open surgery. We have recently performed laparoscopic nephrectomy in ten infants with MCDK. This option was chosen by the parents’ families after being informed of the risks of laparoscopic nephrectomy and the potential morbidity associated with conservative management. As a result, they were fully satisfied after the nephrectomy. Furthermore, based on our calculation of the cumulative cost of management of children with unilateral MCDK, laparoscopic nephrectomy is less expensive than conservative follow-up if it takes more than 3 years for natural involution (Table 1, [5]). The cost for conservative management is based on the charge of the outpatient clinic visit where the physical examination, measurements of blood pressure, and ultrasound examination were performed. The frequency of the clinic attendance is monthly during the first 3 months, trimonthly between 3 months and 12 months of age, at 6 months’ intervals between 1 and 2 years of age, and yearly thereafter [5]. Thus, we currently favor a less invasive laparoscopic nephrectomy for unilateral MCDK over long-term conservative management because of its cost-effectiveness and avoidance of complications. However, the final decision should be made by the family after being fully informed. K. Kaneko Department of Pediatrics, Juntendo University Urayasu Hospital, Chiba, Japan

Should determination of the karyotype be systematic for all malformations detected by obstetrical ultrasound?

The aim of this study was to determine whether karyotyping should be performed for every fetal malformation detected in low risk populations. A karyotype was obtained from 428 fetuses examined over a 10-year period after fetal malformation was diagnosed using obstetrical ultrasound. These fetuses were separated into two groups, one with isolated malformations and the other with multiple malformations. The association between each type of malformation and the result of karyotype was evaluated. Forty-eight chromosomal abnormalities were encountered in 428 fetuses (11.2%). The karyotype was abnormal in 32/343 (9.3%) fetuses with isolated malformations and 16/85 (18.8%) fetuses with multiple malformations (p=0.022). The probability of an abnormal karyotype among the group of isolated malformation depended on the anatomical system involved (p<0.001). Our study demonstrated several isolated malformations without chromosomal abnormality (hydronephrosis with high obstruction, unilateral multicystic dysplastic kidney, gastroschisis, intestinal dilatation, meconium peritonitis, cystic adenomatoid malformation, pulmonary sequestration, tumor, vertebral anomaly). Each fetus with multiple malformations needs a chromosomal analysis. Within the group of isolated malformations, our study emphasizes that medical maternal history and the type of malformation need to be taken into account before performing a fetal karyotype.

Natural history of multicystic kidney conservatively managed: a prospective study.

We report the long-term clinical results of conservative management of children with unilateral multicystic dysplastic kidneys (MCDK). Between 1989 and 2002, 43 children with MCDK detected by prenatal ultrasonography were prospectively followed. At birth, ultrasonography confirmed the prenatal findings in all cases. Patients underwent a radioisotope scan and micturating cystogram in order to confirm the diagnosis and to exclude other uropathies. Follow-up ultrasound (US) examinations were performed at 6-month intervals during the first 2 years of life and yearly thereafter. The mean follow-up time was 42 months (range 12-156 months). Two children developed hypertension during follow-up. In total 257 US scans were performed. The mean number of US scans per patient was 6 (range 3-10). US scans demonstrated partial involution of the MCDK in 30 (70%) cases and complete involution in 8 (19%). The absolute MCDK length remained almost unchanged in 5 children (11%). The estimated median time of complete involution of the MCDK was 122 months [95% confidence interval (CI)=86-158 months]. A total of 33 (76.7%) contralateral kidneys underwent compensatory hypertrophy, reaching a renal length above the 95th percentile during follow-up. The estimated median time for the occurrence of compensatory hypertrophy was 30 months (95% CI=15-45 months). In conclusion, the natural history of MCDK is usually benign but patients must have long-term follow-up with US scans and blood pressure measurements.

Nephrectomy for multicystic dysplastic kidney: if and when?

Objectives To evaluate the criteria for conservative versus surgical treatment of multicystic dysplastic kidneys and to attempt to specify the optimal timing for surgery, when considered indicated. Methods The study population comprised 48 antenatally or neonatally detected consecutive patients with unilateral multicystic dysplastic kidney. The fate of the affected renal conglomerate was regularly analyzed by ultrasonography. All cases were primarily followed up conservatively. In the patients who eventually underwent nephrectomy, the decision to operate was made after a minimum of 18 months (median 25). Results Ultrasound follow-up showed complete involution in 13 cases (27%); in 35 cases (73%), the renal conglomerate persisted throughout the study period (mean 46 months). Of the 48 patients, 32 (67%) eventually underwent nephrectomy. The size of the affected mass among the involuted cases was significantly smaller throughout the study period than in those requiring nephrectomy. The difference between the two groups continuously increased during follow-up, with a mean involution rate of 2.5 cm/yr versus 0.6 cm/yr (up to 18 months) for the involuted versus noninvoluted cases, respectively ( P <0.0001). From 18 months on, no statistically significant involution was observed in those who eventually underwent nephrectomy. Conclusions Patients with antenatally or neonatally detected multicystic dysplastic kidney can primarily be followed up conservatively. Involution occurs in approximately one fourth of the cases, usually within about 14 months. In our experience, no significant involution can be expected to occur after 18 months. If surgery is decided on, we recommend an age of about 2 years. Late complications (eg, Wilms' tumor and renovascular hypertension) are rare.

Unilateral multicystic dysplastic kidney: experience in children.

To report a retrospective study of unilateral multicystic dysplastic kidneys (MCDK) in children, assessing the contralateral kidneys and urinary tract, the functional consequences, and the urological and nephrological management and outcome, as unilateral MCDK is the most common cause of renal cystic disease in children, and malformations of the contralateral urinary tract and kidney (pelvi-ureteric obstruction, megaureter, reflux, renal dysplasia) have been reported. The study included 97 patients (60 boys, 37 girls) with MCDK seen between 1985 and 1998; 82 were diagnosed in utero by ultrasonography (US). After birth, the diagnosis was verified by US, renal scanning (in 93) or intravenous urography (in four), and 89 (92%) had voiding cysto-urethrography (VCUG). Of the 97 children, 87 (90% had a mean (range) follow-up of 44.3 (15-115) months. The MCDK was removed in 17 children; the follow-up of 75 children (five lost to follow-up) showed total involution of the MCDK in 25%, shrinkage in 60% and a stable size in 15%. None had any sign of malignancy. The contralateral kidney showed anomalies in 19 of 97 children (20%); 12 had a dilated renal pelvis (two with megaureter), six had a high echogenicity of the contralateral kidney (one had reflux, and two also pelvic dilatation). In only four of the 89 children was reflux found by VCUG; 16 of the 19 anomalies were detected by US. Five children needed surgery on the contralateral urinary tract (three a pyeloplasty, and one each a pyeloplasty plus ureteroneocystostomy, and an antireflux procedure). Of the contralateral kidneys 43% showed compensatory hypertrophy. There was mild renal insufficiency in three children; renal function seemed to be slightly impaired in many. Five infants had hypertension (four with spontaneous resolution) caused by renal scarring after pyelonephritis or inborn dysplasia of the contralateral kidney. There were symptomatic urinary tract infections in seven children. US can be used safely to diagnose unilateral MCDKs and malformations of the contralateral urinary tract and kidney. In cases where US of the dysplastic kidney remains uncertain renal scintigraphy is necessary to detect the lack of renal function. The low rate of reflux makes routine VCUG unnecessary if the contralateral upper urinary tract and kidney appear to be normal on US. Nephrectomy of the dysplastic kidney in typical cases is also unnecessary. A long-term nephro-urological follow-up of children with MCDK is recommended.

Displasia renal multiquística unilateral y megacaliosis contralateral. Una asociación inusual

Dilation of the genitourinary tract is not always synonymous with obstruction. It is well known that malformations with apparent hydronephrosis and normal urinary flow can exist. In addition, two or more distinct malformations of the genitourinary tract can coexist in the same patient. We present a case of coexistence of a unilateral multicystic dysplastic kidney and contralateral megacalycosis associated with ipsilateral distal segmental megaureter. This association is unusual in the literature. Glomerular renal function was normal, with only a slight defect of renal concentration capacity.