Frequency of Confirmed Congenital Renal Malformations in Neonates with Antenatal Diagnosis of Renal Anomalies Presenting In Neonatal Intensive Care Unit of a Tertiary Care Setting of a Low Income Country.

INTRODUCTION:: Approximately 20 to 30% of all anomalies identified in the prenatal period are congenital anomalies of the kidney and urinary tract (CAKUT). Widespread antenatal screening has resulted in increased detection of anomalies of the kidneys and urinary tract. There are limited studies on the postnatal confirmation of these antenatally detected renal malformations. Moreover, there is no local data available in this regard. So, we conducted the study so that we can obtain local data as well as we can plan management and prevention protocols for such chronically, and sometimes critically, ill neonates. MATERIALS AND METHODS:: It was a cross-sectional study conducted at the neonatal intensive care unit (NICU) at the National Institute of Child Health, Karachi during 2017-2018. The sample size was 100 cases. The sampling technique was non-probability consecutive sampling. All neonates aged 1-28 days of either gender admitted in NICU with antenatal diagnosis of congenital renal anomalies on anomaly scan were included in the study. Preterm neonates (gestational age below 34 weeks) and neonates having siblings with similar congenital problems were excluded. RESULTS:: The mean age of the neonates in our study was 10.17 ±9.30 days and the mean gestational age at birth was 36.65 ±1.16 weeks. The majority of the neonates, that is 65%, were males while 35% were females. Sixty-six per cent (66%) neonates were ≤10 days of age while 34% were >10 days of age. Fifty five% of the neonates were ≤36 weeks of gestation at birth while 45% were >36 weeks of gestation at birth. Frequency of postnatally confirmed congenital renal malformation was observed in 78 (78%) neonates. Neonates whose age at presentation was >10 days were slightly more likely to have confirmed congenital renal malformation as compared to neonates with ≤10 days of age, which is 85.3 % vs 74.2 % (p-value 0.206). Males and females were found to have almost equal postnatally confirmed congenital renal malformations (78.5 % in males and 77.1% in females) (p-value 0.879). Postnatally confirmed congenital renal malformations were observed more commonly in neonates who were >36 weeks of gestational age (80%) as compared to those ≤36 weeks of gestational age (76.4%) (p-value 0.662). CONCLUSION::The frequency of confirmed congenital renal malformation was found higher in neonates presenting with antenatal diagnosis of renal anomalies presenting in the neonatal intensive care unit.

Main Physical Features, Echocardiographic and Renal Ultrasonographic Findings of Turner Syndrome in 107 Pediatric Patients

Turner syndrome (TS) is one of the most common malformation syndromes in females. A total number of 107 TS patients, diagnosed between 2000 and 2018, were evaluated for their phenotypic features, and cardiac and renal findings. The mean age of patients at admission was 10.08 ± 4.9 years (range, newborn to 18 years). Four different karyotype groups were encountered, and the most common findings in all groups were short stature, followed by cubitus valgus. Echocardiographic findings of 85 patients were available among which 63 (<i>n</i> = 63/85, 74.1%) were found to be normal. The most common cardiac anomaly was left ventricular outflow tract/aortic arch pathology detected in 9 patients (<i>n</i> = 9/22, 40.9%). Renal malformations were detected in 15 patients (<i>n</i> = 15/84, 17.9%) by renal ultrasonography, and horseshoe kidney was the most common renal malformation, followed by left multicystic dysplastic kidney. There was no significant difference in the frequency of renal malformation and cardiac anomalies among the 4different karyotype groups (χ² exact test, <i>p</i> &#x3e; 0.05). Compared with the literature, the frequency of renal anomalies was detected at a lower rate. Karyotype analysis should be carried out in all female patients with short stature, even if there are no associated phenotypic findings suggestive of TS. Since cardiac anomalies are frequently seen in TS patients and they represent a common cause of mortality, echocardiography should be carried out as soon as the definite diagnosis is established. Renal anomalies may be less frequent than cardiac anomalies; however, evaluation of TS patients with renal ultrasonography should be done at the time of diagnosis. Although renal ultrasonography can be used as the initial renal screening in TS patients, it may underestimate the frequency of renal malformation; hence, further management may be required.

Hyperuricemia Is an Early and Relatively Common Feature in Children with HNF1B Nephropathy but Its Utility as a Predictor of the Disease Is Limited

Background: Hyperuricemia is recognized as an important feature of nephropathy, associated with a mutation in the hepatocyte nuclear factor-1B (HNF1B) gene, and could serve as a useful marker of the disease. However, neither a causal relationship nor its predictive value have been proven. The purpose of this study was to assess this in children with renal malformations, both with (mut+) and without HNF1B mutations (mut-). Methods: We performed a retrospective analysis of clinical characteristics of pediatric patients tested for HNF1B mutations, collected in a national registry. Results: 108 children were included in the study, comprising 43 mut+ patients and 65 mut- subjects. Mean sUA was higher and hyperuricemia more prevalent (42.5% vs. 15.4%) in HNF1B carriers. The two groups were similar with respect to respect to age, sex, anthropometric parameters, hypertension, and renal function. Renal function, fractional excretion of uric acid and parathyroid hormone level were independent predictors of sUA. The potential of hyperuricemia to predict mutation was low, and addition of hyperuricemia to a multivariate logistic regression model did not increase its accuracy. Conclusions: Hyperuricemia is an early and common feature of HNF1B nephropathy. A strong association of sUA with renal function and parathyroid hormone limits its utility as a reliable marker to predict HNF1B mutation among patients with kidney anomalies.

Hypercalcemia in an Infant With Pseudohypoaldosteronism Type 1

Background: Pseudohypoaldosteronism type 1 (PHA1) is an aldosterone resistance syndrome due to insensitivity of target tissues to aldosterone action, with supraphysiologic aldosterone and renin levels. PHA1 presents usually in infancy and is divided into autosomal dominant (AD) and autosomal recessive (AR) form. A secondary form of PHA1 associated with UTI and/or renal malformations was described. In AD PHA1, salt loss is due to renal mineralocorticoid resistance while hyponatremia in AR PHA1 is caused by multi-organ salt loss. PHA1 has variable signs/symptoms associated with hyponatremia and hyperkalemia; thus, this clinical picture can be attributed to more common conditions such as dehydration, poor feeding, congenital adrenal hyperplasia. Clinical Case: A 5-month old male was admitted for airway evaluation. He was a 23-week gestation preemie, with chronic lung disease, failure to thrive. Patient was found to have hyponatremia, hyperkalemia, high FeNa of 1.3% (intrinsic renal disease) and elevated BUN/Cr (92/1.15). Renal US found echogenic kidneys with poor cortical medullary differentiation suggesting renal disease. Further evaluation noted high aldosterone (1700 ng/dL) and renin (400 ng/mL/hr) levels. He was placed on low protein formula to help optimize BUN level. Baby was diagnosed with secondary PHA1 due to renal disease and started on NaCl supplementation. This led to normalization of BUN, creatinine and improvement in electrolytes. Patient also had high serum calcium ranging from 11.1 to 12.0 mg/dL. Hyponatremia, hyperkalemia, hypercalcemia could be attributed to possible CAH, however state screen and ACTH stimulation test were normal. Further workup showed high 25-OH-vitamin D &gt; 99 ng/mL, PTH 46.9 pg/mL, phosphorous 5.4 mg/dL and 1,25-OH-vitamin D 63.1 pg/mL. Urine Ca/cr ratio was 0.522. Vitamin D supplementation was stopped and daily total fluids increased. Subsequently, there was improvement in serum Ca at 10.9 mg/dL and 25-OH Vitamin D of 74 pg/mL. Next Generation Sequencing (NGS) was carried out, with a focus on the etiology of persisting hypercalcemia, including familial forms of hypercalcemia and Williams Syndrome. NGS revealed a likely pathogenic variant, c.2365 + 2T&gt;C (p.?), in NR3C2, consistent with a diagnosis of AD PHA 1. Conclusion: This is a case of AD PHA1, marked by renal mineralocorticoid receptor resistance associated with persisting hypercalcemia. Initial hypercalcemia could be explained by hypervitaminosis D. It is important to note that electrolyte abnormalities, including persistent hypercalcemia, could be also secondary to the kidney disease found on renal US. There are only few reports of hypercalcemia in patients with PHA1 in the literature. In children with electrolyte abnormalities and failure to thrive, monitoring of serum and urine electrolytes would facilitate early accurate diagnosis and timely treatment.

MO043HYPERURICEMIA IS RELATIVELY COMMON IN CHILDREN WITH HNF1B MUTATION, BUT ITS UTILITY AS A CLINICALLY USEFUL MARKER FOR PREDICTING THE MUTATION IS LIMITED

Background and Aims Hyperuricemia is recognized as an important feature of HNF1B nephropathy, and could serve as a good marker of the disease facilitating selection of patients for genetic testing. However, neither the casual relationship nor its predictive value have been proven yet. We thus decided to assess this in a cohort of children with renal malformations with (mut+) and without HNF1B mutations (mut-). Method We performed a retrospective analysis of clinical and genetic results of pediatric patients tested for HNF1B mutations, whose data were collected in a national registry. Hyperuricemia was assessed by using the newest, age- and gender-dependent reference values for serum uric acid (sUA) in children. Results A total of 108 children were included into the study comprising 43 mut+ patients, and 65 mut- subjects. Mean sUA was higher in mut+ than in mut- subjects (p = 0.006), and hyperuricemia was more prevalent in those with HNF1B mutations (42.5% vs. 15.4%, p = 0.002). Renal phenotype analysis revealed renal hyperechogenicity and multicystic dysplastic kidney disease were more frequent in mut+ patients, but no influence of any renal features/phenotypes on hyperuricemia was found. The two patient cohorts were different with regard to pancreatic anomaly (p &lt; 0.001), glucose metabolism disorders (p = 0.003), hypomagnesemia (p &lt; 0.001), and hyperparathyroidism (p &lt; 0.001). In a multivariate linear stepwise regression model, eGFR, fractional excretion of uric acid, impairments in glucose metabolism and pancreatic anomaly were found to be independent predictive variables of sUA (R2=0.67, F=13.27, p &lt; 0.001). Mutation was not identified as a determinant of sUA. After exclusion of patients with hyperglycemia and/or pancreatic malformations, the difference in hyperuricemia prevalence did not persist between mut+ and mut-. Potential of hyperuricemia for mutation prediction was tested in a model with hypomagnesemia and hyperparathyroidism, which showed an accuracy of 85% (sensitivity: 83%, specificity: 86%). Adding hyperuricemia to the model did not increase the accuracy (79%; sensitivity: 77%, specificity: 82%). Information gain, which informs selective potential of each parameter, was the lowest for hyperuricemia (0.34 compared with 0.99 and 0.63 for hyperparathyroidism and hypomagnesemia, respectively). Conclusion Hyperuricemia is relatively common in children with HNF1B mutation, however its direct association with this molecular defect remains still unproven. Its dependence on renal function and hyperglycemia diminishes the utility as a clinically useful marker for predicting HNF1B disease.

A case report of VACTERL syndrome (anorectal, cardiac and renal malformations)

Introduction. VACTERL is a rare condition, named after the spectrum of malformations characterizing it: vertebral/vas­cu­lar anomalies, anal atresia, cardiac malformations, tracheo-esophageal fistula, renal anomalies, limb ano­ma­lies. Case presentation. We report the case of a male infant who presented in our clinic with the suspicion of inborn error of metabolism due to the severe metabolic acidosis and hypoglycemia. He was operated in the second day of life for imperforate anus and rectoperineal fistula. The radiological examination revealed severe bronchopneumonia for which he required antibiotic treatment and electrolyte infusions for the correction of the acidosis. Starting from the anorectal anomalies, we performed imagistic investigations that detected atrial septal defect and unilateral kidney agenesis. Based on the presence of three specific anomalies, we could establish the diagnosis of VACTERL association and we started the supportive treatment. Conclusions. VACTERL association is a complex spectrum of malformations, some of them with high mortality if they are not corrected on the right moment.

Clinical delineation, sex differences, and genotype–phenotype correlation in pathogenic KDM6A variants causing X-linked Kabuki syndrome type 2

Purpose The variant spectrum and the phenotype of X-linked Kabuki syndrome type 2 (KS2) are poorly understood. Methods Genetic and clinical details of new and published individuals with pathogenic KDM6A variants were compiled and analyzed. Results Sixty-one distinct pathogenic KDM6A variants (50 truncating, 11 missense) from 80 patients (34 males, 46 females) were identified. Missense variants clustered in the TRP 2, 3, 7 and Jmj-C domains. Truncating variants were significantly more likely to be de novo. Thirteen individuals had maternally inherited variants and one had a paternally inherited variant. Neonatal feeding difficulties, hypoglycemia, postnatal growth retardation, poor weight gain, motor delay, intellectual disability (ID), microcephaly, congenital heart anomalies, palate defects, renal malformations, strabismus, hearing loss, recurrent infections, hyperinsulinism, seizures, joint hypermobility, and gastroesophageal reflux were frequent clinical findings. Facial features of over a third of patients were not typical for KS. Males were significantly more likely to be born prematurely, have shorter stature, and severe developmental delay/ID. Conclusion We expand the KDM6A variant spectrum and delineate the KS2 phenotype. We demonstrate that the variability of the KS2 phenotypic depends on sex and the variant type. We also highlight the overlaps and differences between the phenotypes of KS2 and KS1.

Whole-exome sequencing identified a novel heterozygous mutation of SALL1 and a new homozygous mutation of PTPRQ in a Chinese family with Townes-Brocks syndrome and hearing loss

Background Previous studies have revealed that mutations of Spalt Like Transcription Factor 1 (SALL1) are responsible for Townes-Brocks syndrome (TBS), a rare genetic disorder that is characterized by an imperforate anus, dysplastic ears, thumb malformations and other abnormalities, such as hearing loss, foot malformations, renal impairment with or without renal malformations, genitourinary malformations, and congenital heart disease. In addition, the protein tyrosine phosphatase receptor type Q (PTPRQ) gene has been identified in nonsyndromic hearing loss patients with autosomal recessive or autosomal dominant inherited patterns. Methods A Chinese family with TBS and hearing loss was enrolled in this study. The proband was a two-month-old girl who suffered from congenital anal atresia with rectal perineal fistula, ventricular septal defect, patent ductus arteriosus, pulmonary hypertension (PH), and finger deformities. The proband’s father also had external ear deformity with deafness, toe deformities and PH, although his anus was normal. Further investigation found that the proband’s mother presented nonsyndromic hearing loss, and the proband’s mother’s parents were consanguine married. Whole-exome sequencing and Sanger sequencing were applied to detect the genetic lesions of TBS and nonsyndromic hearing loss. Results Via whole-exome sequencing and Sanger sequencing of the proband and her mother, we identified a novel heterozygous mutation (ENST00000251020: c.1428_1429insT, p. K478QfsX38) of SALL1 in the proband and her father who presented TBS phenotypes, and we also detected a new homozygous mutation [ENST00000266688: c.1057_1057delC, p. L353SfsX8)] of PTPRQ in the proband’s mother and uncle, who suffered from nonsyndromic hearing loss. Both mutations were located in the conserved sites of the respective protein and were predicted to be deleterious by informatics analysis. Conclusions This study confirmed the diagnosis of TBS at the molecular level and expanded the spectrum of SALL1 mutations and PTPRQ mutations. Our study may contribute to the clinical management and genetic counselling of TBS and hearing loss.

Whole-exome Sequencing Identified a Novel Heterozygous Mutation of SALL1 and a New Homozygous Mutation of PTPRQ in a Chinese Family With Townes-brocks Syndrome and Hearing Loss

Background: Previous studies have revealed that mutations of Spalt Like Transcription Factor 1 (SALL1) are responsible for Townes-Brocks syndrome (TBS), a rare genetic disorder that is characterized by an imperforate anus, dysplastic ears, thumb malformations and other abnormalities, such as hearing loss, foot malformations, renal impairment with or without renal malformations, genitourinary malformations, and congenital heart disease (CHD). In addition, the protein tyrosine phosphatase receptor type Q (PTPRQ) gene has been identified in nonsyndromic hearing loss patients with autosomal recessive or autosomal dominant inherited patterns.Methods: A Chinese family with TBS and hearing loss was enrolled in this study. The proband was a two-month-old girl who suffered from congenital anal atresia with rectal perineal fistula, ventricular septal defect, patent ductus arteriosus, pulmonary hypertension (PH), and finger deformities. The proband’s father also had external ear deformity with deafness, toe deformities and PH, although his anus was normal. Further investigation found that the proband’s mother presented nonsyndromic hearing loss, and the proband’s mother’s parents were consanguine married. Whole-exome sequencing and Sanger sequencing were applied to detect the genetic lesions of TBS and nonsyndromic hearing loss.Results: Via whole-exome sequencing and Sanger sequencing of the proband and her mother, we identified a novel heterozygous mutation (ENST00000251020: c.1428_1429insT, p. K478QfsX38) of SALL1 in the proband and her father who presented TBS phenotypes, and we also detected a new homozygous mutation (ENST00000266688: c.1057_1057delC, p. L353SfsX8)) of PTPRQ in the proband’s mother and uncle, who suffered from nonsyndromic hearing loss. Both mutations were located in the conserved sites of the respective protein and were predicted to be deleterious by informatics analysis.Conclusions: This study confirmed the diagnosis of TBS at the molecular level and expanded the spectrum of SALL1 mutations and PTPRQ mutations. Our study may contribute to the clinical management and genetic counselling of TBS and hearing loss.

Bardet-Biedl syndrome presented as chronic kidney disease with rare clinical associations in a Sudanese woman (case report)

Bardet–Biedl syndrome is a rare autosomal recessive disorder falls under the spectrum of ciliopathy disorders. Its characterized by rod-cone dystrophy, renal malformations, postaxial polydactyly, learning difficulties, central obesity and hypogonadism. Hyponatremia, hepatic haemangioma, gall bladder stones and subclinical hypothyroidism rarely described in the literature as clinical presentations in BBS.