Fetal renal anomalies and genetic syndromes

Brain and spine malformations and neurodevelopmental disorders in a cohort of children with CAKUT

BACKGROUND

Congenital anomalies of the kidney and urinary tract (CAKUT) represent 20-30% of all birth defects and are often associated with extra-renal malformations. We investigated the frequency of brain/spine malformations and neurological features in children with CAKUT.

METHODS

We reviewed the clinico-radiological and genetic data of 199 out of 1,165 children with CAKUT evaluated from 2006 to 2023 (99 males, mean age at MRI 6.4 years) who underwent brain and/or spine MRI. Patients were grouped according to the type of CAKUT (CAKUT-K involving the kidney and CAKUT-H involving the inferior urinary tract). Group comparisons were performed using χ2 and Fisher exact tests.

RESULTS

Brain/spine malformations were observed in 101/199 subjects (50.7%), 8.6% (101/1165) of our CAKUT population, including midbrain-hindbrain anomalies (40/158, 25.3%), commissural malformations (36/158, 22.7%), malformation of cortical development (23/158, 14.5%), Chiari I anomaly (12/199, 6%), cranio-cervical junction malformations (12/199, 6%), vertebral defects (46/94, 48.9%), caudal regression syndrome (29/94, 30.8%), and other spinal dysraphisms (13/94, 13.8%). Brain/spine malformations were more frequent in the CAKUT-K group (62.4%, p < 0.001). Sixty-two subjects (62/199, 31.2%) had developmental delay/intellectual disability. Neurological examination was abnormal in 40/199 (20.1%). Seizures and/or electroencephalographic anomalies were reported in 28/199 (14%) and behavior problems in 19/199 subjects (9%). Developmental delay/intellectual disability was more frequent in kidney dysplasia (65.2%) and agenesis (40.7%) (p = 0.001).

CONCLUSIONS

We report a relative high frequency of brain/spine malformations and neurodevelopmental disorders in children with CAKUT who underwent MRI examinations in a tertiary referral center, widening the spectrum of anomalies associated with this condition.

Prenatal diagnosis and outcomes for fetuses with suspected pelvic kidney

OBJECTIVE

Evaluation of demographic characteristics and postnatal outcomes of patients with suspected fetal pelvic kidney diagnosis followed in a tertiary center.

METHODS

This retrospective study was conducted in Ankara Bilkent City Hospital perinatology clinic between 2020-2023. Demographic features, prenatal ultrasound findings, and postnatal outcomes were reported.

RESULTS

Pelvic kidney localization was on the left in 11(55 %) patients, on the right in 7(35 %), and bilateral in 2(10 %) patients in prenatal ultrasonography. The gender of the 12(60 %) fetuses were male and 8(40 %) of them were female. The pelvic kidney was an isolated finding in 8(40 %) fetuses, additional findings were present in the remaining 12(60 %) fetuses. Pelvic kidney was confirmed postnatally by ultrasound in all 18 fetuses. However two cases with prenatal ultrasound findings resulted in intrauterine fetal demise and the final diagnosis could not be confirmed as the parents refused autopsia. Cases were divided into 3 groups according to postnatal follow-up duration as 0-12 months (n = 7), 12-24 months (n = 7) and 24-44 months (n = 4). Atrial septal defect was the most common accompanying abnormality in the postnatal period (n = 4). Smaller kidney size (n = 7), vesicoureteral reflux (n = 3), and impaired renal function (n = 3) were the most common postnatal complications.

CONCLUSION

Pelvic kidney can be diagnosed in fetal abnormality screening ultrasound and postnatal follow-up should be performed closely for the assessment of renal functions.

The role of magnetic resonance imaging in refining the diagnosis of suspected fetal renal anomalies

OBJECTIVE

This prospective study was designed to detect the role of magnetic resonance imaging (MRI) in refining the diagnosis of suspected fetal renal anomalies detected during screening sonography.

MATERIAL AND METHODS

54 pregnant women, with suspected fetal renal anomalies detected during routine ultrasound screening, were rescanned by MRI to refine the diagnosis of the suspected renal anomalies. The pregnancy outcome was examined externally and by postnatal ultrasonography.

RESULTS

Fifty-four cases of suspected renal anomalies detected during screening sonography of 8400 pregnant women (0.6%), were res-canned by MRI in this study. The MRI gave a similar diagnosis to postnatal ultrasound in 46 cases (16 cases of hydronephrosis, 14 cases of Polycystic Kidney Disease (PCKD), 9 cases of Multicystic Kidney Disease (MCKD), 2 cases of Renal Agensis (RA), 3 cases of single renal cyst and 2 cases of megacystis+hydroureter), while it gave a different diagnosis (false positive) in 6 cases (4 cases of hydronephrosis diagnosed by MRI confirmed to be PCKD by postnatal ultrasound, also, 1 case of MCKD diagnosed by MRI confirmed to be hydronephrosis by postnatal ultrasound and 1 case of RA diagnosed by MRI confirmed to be normal by postnatal ultrasound). The prenatal ultrasound gave a similar diagnosis to postnatal ultrasound in 43 cases (14 cases of hydronephrosis, 13 case of PCKD, 9 cases of MCKD, 2 cases of RA, 3 cases of single renal cyst and 2 case of megacystis+hydroureter), while it gave a different diagnosis (false positive) in 9 cases; 4 cases of hydronephrosis diagnosed by prenatal sonography confirmed to be PCKD by postnatal ultrasound, one case of PCKD+one case of MCKD, and one case of megacystis+hydroureter confirmed to be hydronephrosis by postnatal ultrasound, while one case of MCKD diagnosed by prenatal sonography was confirmed to be PCKD by postnatal ultrasound and one case of RA diagnosed by prenatal ultrasound was confirmed to be normal by postnatal ultrasound.

CONCLUSION

The MRI can be used as a complementary adjunctive modality with excellent tissue contrast, especially in equivocal cases or inconclusive sonographic findings.

Post-mortem examination of prenatally diagnosed fatal renal malformation

OBJECTIVE

Renal malformations can be associated with genetic syndromes and chromosomal disorders. Fetal autopsy including histopathological examination of kidney is important to arrive at definite diagnosis. The objective was to assess importance of fetal autopsy and histopathology.

STUDY DESIGN

Retrospective analysis of cases with fetal renal malformations was done. All fetuses terminated were examined with whole body radiograph, external and internal examination and histopathological examination.

RESULT

A total of 21 cases with renal malformations were studied. Of all 3 were of bilateral renal agenesis, 4 showed autosomal recessive polycystic kidney disease and 13 showed features of multicystic kidney. Three of these had hyperplasic-enlarged bladder and autopsy confirmed urorectal septum malformations in two cases and posterior urethral valve in one case. One case had associated malformations like encephalocele that suggested diagnosis of Meckel-Gruber syndrome and another had associated lateral body wall defect. In five cases kidney was hypoplastic suggestive of Potter type IIa.

CONCLUSION

Ultrasound is an effective diagnostic modality; however fetal autopsy after termination of pregnancy is important to arrive at a definitive diagnosis. It's important to distinguish between autosomal recessive polycystic kidney disease (ARPKD) and cystic dysplastic kidney as recurrence risk is 3% in case of cystic renal dysplasia in contrast to 25% in case of ARPKD. Gross examination may point toward syndromic diagnosis like Meckel-Gruber syndrome; hence mode of prenatal diagnosis may vary in subsequent pregnancies.

Upper urinary tract dilatation: prenatal diagnosis, management and outcome

Upper urinary tract dilatation is one of the most common abnormalities detected on prenatal ultrasound scanning. It is commonly due to transient urine flow impairment (UFI) at the level of the pelvi-ureteric and vesico-ureteric junctions, which improves with time in most cases. It is usually in the neonatal period that the diagnosis is confirmed and during the first 18 months of life that the prognosis of the dilatation is defined.

Perinatal assessment of hereditary cystic renal diseases: the contribution of sonography

The aims of this review article were to clarify the steps that may lead to a proper diagnosis of fetal and neonatal renal cystic diseases. All the hereditary cystic diseases are reviewed and a classification is proposed. The various sonographic patterns that can be used to ascertain the diagnosis are also reviewed. Finally, tables with differential diagnoses are presented to help the reader in the work-up of such pathologies.

Congenital renal tract anomalies: outcome and follow-up of 402 cases detected antenatally between 1986 and 2001

OBJECTIVE

To determine the long-term prognosis of antenatally detected renal tract anomalies in order to optimize parental counseling.

METHODS

This was a follow-up study of all renal tract abnormalities detected antenatally in a Level 3 ultrasound department between 1986 and 2001. Follow-up data (median age, 8 years) were retrieved from the records of the Paediatric Urology Department or the attending pediatrician.

RESULTS

A urinary tract anomaly was detected in 408 fetuses. There were four false-positive diagnoses. From two children follow-up data were incomplete, leaving 402 cases for analysis. A chromosomal abnormality was present in 7/81 (8.6%) fetuses that had karyotyping. Termination of pregnancy was performed in 55 (13.7%) cases and a further 66 (16.4%) children died during the perinatal period and up to 1 year of age. In 106/121 (26.4% of all fetuses) deceased children the cause of death was directly related to the renal tract anomaly. In the 281 surviving children a total of 545 renal tract anomalies were diagnosed postnatally, requiring a total of 381 surgical interventions in 156 infants. Outcome in survivors was generally good, with impaired renal function in nine infants and hypertension in three (4% of the survivors).

CONCLUSIONS

Congenital renal tract anomalies are associated with a high mortality rate, especially when they are structural developmental anomalies of the kidneys. Survivors require multiple operations, but the outcome is generally favorable. Ultrasound diagnosis, especially when made early, of non-lethal urinary tract anomalies may prevent additional renal damage by timing of delivery and early postnatal treatment.