Associated urologic anomalies in children with solitary kidney

Nephrotic Syndrome Associated with Hydronephrosis and Unilateral Renal Agenesis

We reported a case of nephrotic syndrome in a child presenting undiagnosed hydronephrosis and unilateral renal agenesis in a 3 years and 9 months old male patient presenting features of nephrotic syndrome, with left hydronephrosis and unilateral renal agenesis. The association of nephrotic syndrome with congenital anomalies is extremely rare. The importance of this unusual combination was discussed respecting the literature.

Retrospective evaluation of children with unilateral renal agenesis

BACKGROUND

Children born with unilateral renal agenesis (URA) are thought to have a risk of developing hypertension, proteinuria, and progressive chronic kidney disease (CKD). The present study aimed to evaluate the long-term prognosis and clinical characteristics of children with URA.

METHODS

The study included 171 patients aged < 18 years diagnosed as URA who were followed-up for ≥ 1 year and 121 healthy controls matched for age, gender, and BMI.

RESULTS

Median age at diagnosis was 2 years (IQR: 1 month-16 years) and the incidence of URA in males (65.4%) was higher than in females. Among the patients, 21 (12.2%) had other urinary system anomalies. It was noted that 2.3% of the patients had proteinuria, 15.2% had hyperfiltration, and 2.9% had CKD. Hypertension based on ambulatory blood pressure monitoring (ABPM) was diagnosed in 18 (10.5%) of the patients, of whom 10 had masked hypertension. Diastolic blood pressure in the URA patients was significantly higher than in the healthy controls. The incidence of hypertension and CKD was significantly higher in the patients with other urinary system anomalies.

CONCLUSIONS

Patients with a single functional kidney should be periodically evaluated throughout their lifetime for urine protein, blood pressure, and kidney functions. The most remarkable finding of this study is the importance of the use of ABPM for evaluating blood pressure in pediatric URA patients, especially for the detection of masked hypertension and the non-dipper phenomenon, which cannot be achieved with office blood pressure measurement.

Impact of prenatal ultrasound diagnosis for fetal renal abnormalities: Study Protocol

BACKGROUND

This study will evaluate diagnostic accuracy and management outcome studies involving patients assessed with prenatal ultrasound diagnosis (PUD) for fetal renal abnormalities (FRA).

METHODS

We will search the following electronic databases of MEDLINE, EMBASE, Cochrane Library, Web of Science, Springer, Cumulative Index to Nursing and Allied Health Literature, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure for diagnostic accuracy studies from inceptions to the present without language restrictions. Two authors will independently screen studies, collect data, and assess methodological quality.We will use RevMan V.5.3 and Stata V.12.0 software for data pooling and statistical analysis.

RESULTS

In this study, we will assess sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio to determine the diagnostic accuracy of PUD for the treatment of patients with FRA.

CONCLUSION

This study will provide latest evidence for the diagnostic accuracy of PUD for FRA.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019151306.

Congenital unilateral renal agenesis: Prevalence, prenatal diagnosis, associated anomalies. Data from two birth-defect registries

BACKGROUND

The different mechanisms leading to a solitary kidney should be differentiated because the long-term outcome might be different. The fetal period is the best moment to make a true diagnosis of congenital unilateral renal agenesis (URA). The objective was to determine the prevalence of URA at birth. The secondary objectives were to describe the evolution of sensitivity of prenatal diagnosis over time and the different forms of URA (isolated and associated with other malformations) detected up to 1 year.

METHODS

The cases were retrospectively identified through two French population-based birth defect registries (Auvergne and Bas-Rhin) between 1995 and 2013. Stillbirths and fetuses up to 22 weeks of gestation and infants up to 1 year old with URA were included.

RESULTS

A total of 177 cases of URA were registered. The prevalence at birth was 4.0/10,000. The overall prenatal prevalence was 3.6/10,000 (isolated URA: 2.8/10,000). URA were isolated (59.9%), associated with isolated contralateral congenital anomaly of kidney or urinary tract (CAKUT) (7.3%) and with other extra-renal anomalies (32.8%). The total proportion of contralateral CAKUT was 15%. Only three cases presented an aneuploidy, prenatally detected and conducting to a termination of pregnancy. The sensitivity of prenatal diagnosis improved over time (from 54.2% in 1995 to 1997 to 95.8% in 2010 to 2013; p = 0.002).

CONCLUSION

Our study provides estimates of prevalence of URA at birth. A longitudinal cohort from the antenatal period to puberty should be performed to determine the prognosis of the contralateral kidney among these children with isolated, associated with contralateral CAKUT and URA with extra-renal anomalies. Birth Defects Research 109:1204-1211, 2017. © 2017 Wiley Periodicals, Inc.

Unilateral Fetal Renal Abnormalities: Are They Really Isolated?

OBJECTIVES

Our objective was to describe the association between unilateral fetal renal abnormalities and other major anomalies that were not apparent in the second trimester.

METHODS

A review of the ultrasound database identified fetuses with suspected unilateral renal agenesis, unilateral multicystic dysplastic kidney, and renal ectopia from 2005 to 2014. Neonatal records were reviewed to identify anomalies not suspected in the second trimester, and postnatal imaging studies were reviewed. Categorical data were compared by &x003C7;(2) analysis and the Fisher exact test.

RESULTS

We identified 102 cases, including 36 with suspected renal agenesis, 28 with suspected multicystic dysplastic kidney, and 38 with suspected renal ectopia. There were 8 cases (7.8%) with major anomalies not suspected in the second trimester. In 5 cases (4.9%), there were no associated findings in the second trimester. There were no significant differences in the rates of unsuspected abnormalities between the 3 groups. There was a trend toward a higher rate of unsuspected anomalies in the cases with a single umbilical artery compared to those with a 3-vessel cord (28.6% vs 6.3%; P= .09).

CONCLUSIONS

In fetuses with unilateral renal abnormalities, major anomalies that were not suspected in the second trimester were uncommon. However, patients should be aware of the possibility that other major anomalies could subsequently be identified, and the outcome may depend on more than postnatal renal function.

Upper urinary tract anomalies and perinatal renal tumors

Congenital anomalies of the upper urinary tract are common and frequently diagnosed on prenatal ultrasound. In the absence of infection, these anomalies are often asymptomatic. This article reviews key features and long-term implications to assist in discussions with families. In contrast, a perinatal renal tumor is rare but extremely alarming. This update on the most common tumors and their treatment is useful in reassuring parents that most infants, after primary surgical resection, are cured without adjuvant therapies. To understand renal agenesis and other congenital renal malformations and their associated anomalies, a brief review of normal renal development is presented.

Is microalbuminuria a risk factor for hypertension in children with solitary kidney?

BACKGROUND

The correlations between ambulatory blood pressure measurements (ABPM) and serum cystatin C (Cys C), serum creatinine (Cr), microalbumin (MA), and β2-microglobulin (β2-MG) levels in 24 h (24-h) urine were analyzed in children with solitary kidney (SK) and compared to healthy children.

METHODS

Fifty children with normal functioning SK and 25 controls were studied. The ABPM, serum Cys C, serum Cr, MA, and β2-MG levels in 24-h urine were measured in all children. Clinical symptoms and signs, laboratory results, urinary ultrasonography, voiding cystourethrography, and Dimercaptosuccinic acid (DMSA) scintigraphy results were recorded in the SK group. Four patients with Wilms' tumor and two with renal scarring were excluded from the study.

RESULTS

The mean ages of the SK group and controls were 9.6 ± 3.6 and 9.3 ± 3.3 years, respectively. The serum Cys C and Cr levels, 24-h urinary β2-MG and MA levels were similar in both groups (p > 0.05). However, 24-h urinary MA excretion was higher in patients living with SK more than 5 years (p = 0.01). Standard deviation scores of ABPM parameters showed no significant correlation with serum Cr, serum Cys C, MA, and β2-MG in 24-h urine of both groups.

CONCLUSIONS

Children with SK have increased 24-h urinary MA excretion in the long term, and need prolonged follow-up to detect early deterioration of renal function and to prevent end-organ damage later in life.

Renal parenchymal thickness in children with solitary functioning kidney

BACKGROUND

Reduced renal parenchymal thickness (PT) is a parameter used by clinicians to assess the degree of hydronephrosis. In patients with a congenital hydronephrotic solitary functioning kidney (SFK), PT is difficult to determine as there is no comparison with the contralateral kidney. The aim of this study was to obtain ultrasound measurements of PT in children with normal SFK and to compare these data with PT measurements in children with two functioning kidneys.

METHODS

This was a prospective multicenter study carried out between 2006 and 2011 in which 236 children aged 11 days to 18.96 years with healthy SFK were examined. The SFK etiologies were unilateral renal agenesis or a nonfunctioning contralateral kidney, mostly due to multicystic dysplasia. In addition to determining other parameters, we measured PT in the middle third of the kidney by ultrasound. Correlations between PT and age, height and weight were assessed.

RESULTS

Correlation analysis showed a positive correlation with renal PT for all parameters. The correlation coefficients for age, height and weight were 0.863, 0.873 and 0.874, respectively. In most age categories, the renal parenchyma was significantly thicker in the SFK than in two functioning kidneys.

CONCLUSIONS

Based on our results, we suggest that PT in the SFK is correlated with height, weight and age of the patient. Consequently, measurements of PT may be used for monitoring the development of the healthy SFK and may contribute to a more accurate assessment of the severity of SFK anomalies.

Unilateral renal agenesis: a systematic review on associated anomalies and renal injury

BACKGROUND

Unilateral renal agenesis (URA) is associated with other congenital anomalies of the kidney and urinary tract (CAKUT) and extra-renal anomalies. However, the reported prevalences of these anomalies are highly variable. We estimated the prevalence of associated CAKUT and extra-renal anomalies in patients with URA. Furthermore, we determined the prevalence of renal injury in URA patients.

METHODS

We conducted a systematic review of English and non-English articles using PubMed and Embase.com. Included studies reported at least one of the following items: incidence of URA, gender, side of URA, prenatal diagnosis, performance of micturating cystourethrogram, associated CAKUT, urinary tract infection or extra-renal anomalies. Studies that described a mean/median glomerular filtration rate (GFR) and proportions of patients with hypertension, micro-albuminuria or a decreased GFR were also included.

RESULTS

Analyses were based on 43 included studies (total number of patients: 2684, 63% male). The general incidence of URA was 1 in ∼2000. Associated CAKUT were identified in 32% of patients, of which vesicoureteral reflux was most frequently identified (24% of patients). Extra-renal anomalies were found in 31% of patients. Hypertension could be identified in 16% of patients, whereas 21% of patients had micro-albuminuria. Ten per cent of patients had a GFR<60 mL/min/1.73 m2;.

CONCLUSIONS

These aggregate results provide insight in the prevalence of associated anomalies and renal injury in patients with URA. Our systematic review implicates that URA is not a harmless malformation by definition. Therefore, we emphasize the need for clinical follow-up in URA patients starting at birth.

Renal functional reserve in children with apparently normal congenital solitary functioning kidney

OBJECTIVE

The aim of the study was to investigate renal functional reserve (RFR) and to assess its relationship with serum cystatin C and blood pressure in children with apparently normal congenital solitary functioning kidney (SFK).

MATERIAL AND METHODS

RFR was obtained from the difference of endogenous creatinine clearance (CrCs) before and after a meat-free oral protein load (OPL) in the patients who were pre-treated with cimetidine. Serum cystatin C and urinary protein excretion were determined before and after OPL.

RESULTS

Among 22 patients (13 boys), aged 9.5 ± 4.3 years, 72.7% had increased serum cystatin C, and 54.5% had decreased RFR. Following OPL, CrCs and urine creatinine increased, while serum creatinine and cystatin C remained unchanged. The multiple regression analysis demonstrated that cystatin C could predict more than 90% of RFR variability.

CONCLUSION

Half of the patients with apparently normal SFK had decreased RFR. Serum cystatin C is one of the best predictors of RFR.

Congenital ureteric stenosis: a study of 17 children

AIM

To review cases of congenital ureteric stenosis treated in the period between 1999 and 2007. We propose to analyze the type of presentation, management and results.

MATERIAL AND METHODS

We report 17 children aged 20 days to 8 years with obstructive uropathy due to congenital stenosis of the ureter at one or more levels. This condition could be mistaken for the more common pelviureteric junction obstruction (PUJO) or primary megaureter, but it is a distinct and more serious anomaly. 13 of the 17 children had one or more associated anomalies, the most significant of which was a contralateral multicystic dysplastic kidney. Other associated anomalies included PUJO, megacalyx, vesicoureteric reflux, urogenital sinus, duplicate vagina, anorectal malformation and agenesis of the bladder. 16 children were symptomatic at presentation, with uremia (serum creatinine >1 mg/dl) in 5, while 1 was diagnosed antenatally. The correct preoperative diagnosis was made in only three children. Reconstruction included ureteroureteral anastomosis, ureteric reimplantation or ureteral substitution.

RESULTS

There is follow up for 15 of the 17 patients. Length of follow up ranges from 1 to 7 years (average 2.7 years). There was satisfactory urinary drainage established in all 17 cases and uremia has resolved 3 of the 5 children. The children with solitary functioning kidney are at risk of uremia in later life.

CONCLUSION

Congenital ureteric stenosis is a rare condition, but distinct anomaly with possible grave consequence and has been distinguished from other causes of congenital ureteric obstruction.

Postnatal evaluation of infants with an abnormal antenatal renal sonogram

PURPOSE OF REVIEW

Antenatally detected renal abnormalities are frequently encountered. Recommended postnatal evaluation of these infants has evolved to minimize invasive testing while maximizing detection of significant abnormalities.

RECENT FINDINGS

There is a low rate of detectable renal abnormalities in infants with a normal postnatal sonogram at 4-6 weeks of age. Routine prophylactic antibiotics are not indicated in infants with isolated antenatal hydronephrosis. Infants with a multicystic dysplastic kidney and a normal contralateral kidney on renal ultrasound do not require further evaluation. Parents of these children should be counseled on symptoms of urinary tract infections to allow prompt diagnosis.

SUMMARY

All infants with abnormalities on antenatal sonogram should undergo postnatal evaluation with a sonogram after birth and at 4-6 weeks of age. Further evaluation can be safely limited when the postnatal sonogram is normal at 6 weeks of age.

Management and etiology of the unilateral multicystic dysplastic kidney: a review

In children, unilateral multicystic dysplastic kidney (MCDK) is one of the most frequently identified urinary tract abnormalities. A variety of proposed etiologies has been associated with the underlying pathogenesis of MCDK. These include genetic disturbances, teratogens, in utero infections, and urinary outflow tract obstruction. From 5-43% of the time, MCDK has associated genito-urinary anomalies, both structural and functional in nature. A review of the literature reveals that involution rates are reported to be 19-73%, compensatory hypertrophy of the contralateral kidney occurs from 24-81% of the time, and estimated glomerular filtration rates (GFRs) (by the Schwartz formula) range from 86-122 ml/min per 1.73 m(2) body surface area. Most authors suggest serial ultrasonography to monitor contralateral growth, routine blood pressure monitoring, and a serum creatinine monitoring algorithm. The risk of hypertension in those with MCDKs does not appear to be greater than that of the general population, and the rates of malignant transformation of MCDK are small, if at all increased, in comparison with those in the general population. If the patient develops a urinary tract infection or has abnormalities of the contralateral kidney, shown on ultrasound, a voiding cystourethrogram is recommended. Finally, the body of literature does not support the routine surgical removal of MCDKs.

Unilateral multicystic dysplastic kidney: a meta-analysis of observational studies on the incidence, associated urinary tract malformations and the contralateral kidney

BACKGROUND

Many papers are published on cohorts with unilateral multicystic dysplastic kidney (MCDK) patients, but show variable results as to the incidence of associated urinary tract abnormalities. The objective of this study was to describe the status of the urinary tract, including contralateral hypertrophy and malformations, in patients with unilateral MCDK based on a meta-analysis of the literature, taking into account the timing of diagnosis (pre- versus postnatal) as a possible source of bias.

METHODS

A systematic review of the scientific literature in English was conducted using PubMed and Embase. A meta-analysis was performed with the studies that were identified using our reproducible search.

RESULTS

Based on analysis of the data in 19 populations, the overall incidence of unilateral MCDK is 1 in 4300 with an increasing trend over the years. A total of 67 cohorts with over 3500 patients with unilateral MCDK were included in the meta-analysis. Fifty-nine percent of patients were male and the MCDKs were significantly more often found on the left side (53.1%). Associated anomalies in the solitary functioning kidney were found in 1 in 3 patients, mainly vesicoureteric reflux (VUR, in 19.7%). In patients with VUR, 40% have severe contralateral VUR, defined as grade III-V. Contralateral hypertrophy, present in 77% of patients after a follow-up of at least 10 years, showed a trend to be less pronounced in patients with VUR. Timing of the diagnosis of MCDK did not essentially influence the results.

CONCLUSIONS

These aggregate results provide insight into the incidence, demographic data and associated anomalies in patients with unilateral MCDK. One in three patients with unilateral MCDK show anomalies in the contralateral, solitary functioning kidney. However, studies into the long-term consequences of these anomalies are scarce.

Diagnostic approach to reflux in 2007

There is ongoing controversy regarding the association between vesicoureteric reflux (VUR), recurrent urinary tract infections (UTI), and renal damage. Despite this, routine work up for VUR is still recommended after febrile UTI in most children. The present article reviews the indications and imaging modalities available for VUR diagnosis. Alternative newer techniques like MR cystography and voiding urosonography are discussed. The increasing evidence of the role of DMSA scans in managing children with VUR is highlighted.

Dysplastic kidneys

Dysplastic kidneys are common malformations affecting up to 1 in 1000 of the general population. They are part of the spectrum of Congenital Abnormalities of the Kidney and Urinary Tract (CAKUT) and an increasing number of children are being diagnosed on antenatal ultrasound. In the past, these patients may not have been detected until adulthood following investigation for other illness, or even as incidental findings at post mortem, unless there was severe bilateral dysplasia leading to Potter's sequence or renal failure in childhood. Excluding syndromic cases with defects in other organ systems, features linked to worse prognosis at presentation are: (1) bilateral disease; (2) decreased functional renal mass (which encompasses not just small kidneys but also large ones where cysts replace normal architecture); (3) lower urinary tract obstruction; and (4) anhydramnios or severe oligohydramnios. Dysplasia and renal function are dynamic and can evolve during pregnancy, so repeated assessment is necessary when pathology is expected. Worsening dimensions or decreasing amniotic fluid levels imply poorer prognosis, but there are no proven therapies during pregnancy, though vesicoamniotic shunting may be indicated with obstruction. Postnatal investigations aim to define the anatomy, which helps to estimate risks of infection and kidney function. Management might then involve observation, prophylactic antibiotics, surgery and/or renal support. Risks of renal malignancy and hypertension are low during childhood, but longer-term follow-up is needed, particularly to determine blood pressure and renal function in adulthood and pregnancy. Around 10% of cases have a family history of significant renal/urinary tract malformation. Monogenic causes include mutations in individual genes, such as TCF2/hepatocyte nuclear factor 1ss (HNF1beta), PAX2 and uroplakins, but there are also recent reports of children with compound heterozygote mutations in several renal/urinary tract developmental genes. Effective genetic screening in future may require gene chip or other techniques to assess multiple genes concurrently, but this should not replace a multidisciplinary approach to these often difficult cases.

Blood pressure, renal function, and proteinuria in children with unilateral renal agenesis

BACKGROUND/AIM

Unilateral renal agenesis (URA) is a model for a reduced nephron number that is believed to be a risk factor for blood pressure (BP) elevation and reduced renal function. The aim of the study was to investigate BP and renal function in children with URA.

METHODS

Data on children with URA from two pediatric nephrology centers were firstly retrospectively reviewed (renal ultrasound and scintigraphy, clinical BP, creatinine clearance, urinalysis). Children with normal renal ultrasound and scintigraphy were thereafter investigated using ambulatory BP monitoring.

RESULTS

Twenty-nine children with URA were investigated--14 children with an abnormal kidney (mostly scarring) and 15 children with healthy kidneys. Hypertension was diagnosed on the basis of clinical BP in 57% of the children with abnormal kidneys and on the basis of ambulatory BP monitoring in 1 child (7%) with healthy kidneys. The mean ambulatory BP in children with normal kidneys was not significantly different from that in controls. Forty-three percent of the children with abnormal kidneys had a reduced renal function, but none of children with normal kidneys.

CONCLUSIONS

Children with abnormalities of a solitary kidney have often hypertension, proteinuria, or a reduced renal function. In contrast, children with healthy solitary kidneys have BP and renal function similar to those of healthy children.

Mixed germ cell tumor in intra-abdominal testis associated with ipsilateral ectopic dysplastic kidney

Testicular tumor of the cryptorchid testis associated with renal dysplasia is relatively infrequent and indicates maldevelopment during embryogenesis. We report a case of a 31-year-old man with a mixed germ cell tumor found in an intra-abdominal testis associated with an ipsilateral ectopic dysplastic kidney. He underwent orchiectomy with partial cystectomy. Simple nephrectomy was also performed. No evidence of disease recurrence was found at 16 months of follow-up.

Urological anomalies in children with renal agenesis or multicystic dysplastic kidney

This study aimed to determine the frequency of associated urological abnormalities in children with unilateral renal agenesis (RA) or multicystic dysplastic kidney (MCDK). In total, 38 children (10 girls, 28 boys) were studied: 21 with RA and 17 with MCDK. In 14 children (37%) anomalies of the urinary tract were suspected prenatally in ultrasound studies. In the remaining 24 children the diagnosis of RA/MCDK was made postnatally: in 13 (34%) in the first 7 days of life, in 11 (29%) at the age of 8 days to 34 months, mean 10.6+/-8.05 months. Voiding cystourethrography was done in 36 (95%) children, the isotopic 99mTc-EC/DMSA scan of the kidney in 29 (67%), and urography in 8. Urological anomalies were present in 11 (29%) children: in 7 (33%) with RA and in 4 (24%) with MCDK. Vesicoureteral reflux was diagnosed in 8 children: grade II in 4, III in 3, and IV in 1 (in 1 child to duplicated, in 1 to ectopic kidney); ureterovesical junction obstruction in 2 (9.5%); and ureteropelvic junction obstruction in 1 (4.8%). Among them, 2 children demanded surgery on the contralateral urinary tract: pyeloplasty in 1, antireflux procedure in 1; while 9 children were treated conservatively. Compensatory hypertrophy of the contralateral kidney was found in 90% of children. Thus due to an increased risk of pathological changes in the single functioning kidney, lifelong nephrological care is recommended in patients with unilateral RA/MCDK.

Assessment of serum cystatin C in children with congenital solitary kidney

The aim of the study was to assess serum cystatin C level in children with a congenital solitary kidney, depending on their age and compensatory overgrowth of the kidney. The study group (I) consisted of 36 children, 3-21 years of age (median 10.8 years), with a congenital solitary kidney and no other urinary defects. The control group (C) contained 36 healthy children, 5-21 years old (median 10.9 years). Nephelometric methods were used to determine serum cystatin C level, the Jaffe method to assess creatinine concentration and the Schwartz formula to estimate glomerular filtration rate. Kidney length was measured with the patient in a supine position, and overgrowth was estimated (O%) in comparison with the respective kidney in the control group. Serum cystatin C level in group I was higher than that in the control group (P<0.05). Increased values, above 0.95 mg/l, were found in 16/36 (44%) children aged 12-21 years. Glomerular filtration rate (GFR, estimated by the Schwartz formula) and creatinine level in group I were similar to those of the control group (P>0.05). Increased kidney length was found (median 18.2%). Cystatin C concentration was positively correlated with O% (r=0.406, P<0.01) and kidney length to child height ratio (L/H) (r=0.376, P<0.05). We conclude that Increased serum cystatin C concentration in patients with a unilateral congenital solitary kidney occurs after 12 years of age and correlates with compensatory overgrowth of the kidney.

Risk of hypertension with multicystic kidney disease: a systematic review

BACKGROUND

Children with multicystic kidney disease (MCKD) are increasingly managed conservatively, and are followed up throughout childhood because of the risk of hypertension highlighted in some reports. With this risk still poorly defined, the strategy and the duration of follow up do not seem to be based on evidence.

METHODS

Systematic review of the literature for all published cohort studies (prospective and retrospective) of children diagnosed to have unilateral MCKD and managed conservatively. Exclusion criteria were bilateral MCKD, and nephrectomy (not for hypertension) during the follow up period. For children with MCKD, the probability of developing hypertension during the follow up period was estimated.

RESULTS

From 29 reviewed studies, six cases of hypertension developed in 1115 eligible children. The mean probability of a child with unilateral MCKD developing hypertension was therefore 5.4 per 1000 (95% CI estimated at 1.9 to 11.7 per 1000).

CONCLUSION

Although the risk of hypertension in MCKD is low, the results of this study do not allow firm recommendations on the frequency and duration of blood pressure measurement follow up for these children. Large prospective cohort studies with a very long duration of follow up are needed.

Associated anomalies in children with congenital solitary functioning kidney

Congenital solitary functioning kidney (CSFK) is a relatively common renal malformation and in children is frequently complicated by anomalies of the ipsilateral genital organs and occasionally by anomalies of other organs. The aim of this study was to determine the incidence of associated urological, cardiac, gastrointestinal, hematological, neurological, skeletal, and other congenital malformations in children with CSFK. We retrospectively reviewed 87 consecutive cases of CSFK diagnosed at our hospital between 1995 and 2003. There were 45 boys and 42 girls, whose ages at diagnosis ranged from newborn to 16 years (mean 4.67+/-4.48 years). In all patients, CSFK was diagnosed by abdominal ultrasound and confirmed by radionuclide studies. In 46 patients (53%) the left kidney was absent, and in 41 patients (47%) the right kidney was absent. Overall associated anomalies were detected in 52 of the 87 children (60%) with CSFK. Urological anomalies were most common, with an incidence of 37% (32/87). Nonurological anomalies were detected in 38 children (44%) with CSFK; these included cardiac anomalies in 13, gastrointestinal anomalies in eight, hematological anomalies in five, neurological anomalies in three, and other organ anomalies in nine. In our study, more than half of the patients with CSFK had associated anomalies. For this reason we recommend abdominal ultrasound and voiding cystourethrogram for early recognition of urological anomalies and a careful physical examination for other organ anomalies in patients with CSFK.

Risk of Wilms' tumour with multicystic kidney disease: a systematic review

BACKGROUND

Children with multicystic kidney disease (MCKD) are increasingly managed conservatively and are followed up throughout childhood because they are perceived to be at increased risk of developing Wilms' tumour. With this risk still poorly defined and somewhat controversial, the strategy and the duration of follow up do not seem to be based on evidence.

METHODS

Systematic review of the literature for all published cohort studies (prospective and retrospective) of children diagnosed to have unilateral MCKD and managed conservatively.

EXCLUSION CRITERIA

bilateral MCKD, nephrectomy (not for malignancy) during the follow up period. We estimated for children with MCKD the probability of developing Wilms' tumour during the follow up period, with 95% CI using the Poisson distribution.

RESULTS

From 26 reviewed studies, no cases of Wilms' tumour developed in 1041 eligible children. The mean probability of a child with unilateral MCKD to develop Wilms' was therefore nil, with a 97.5% upper CI estimated at 0.0035 (or 3.5 per 1000 children).

CONCLUSION

The development of a national or a European registry for children with MCKD would increase the precision of their risk estimate to develop Wilms' tumour. In the meantime, there is no evidence to support any of the different modalities for following up these children by ultrasound, if indeed such a strategy is necessary.