Case report: KPTN gene-related syndrome associated with a spectrum of neurodevelopmental anomalies including severe epilepsy

Biallelic variants in the kaptin gene KPTN were identified recently in individuals with a novel syndrome referred to as autosomal recessive intellectual developmental disorder 41 (MRT41). MRT41 is characterized by developmental delay, predominantly in language development, behavioral abnormalities, and epilepsy. Only about 15 affected individuals have been described in the literature, all with primary or secondary macrocephaly. Using exome sequencing, we identified three different biallelic variants in KPTN in five affected individuals from three unrelated families. In total, two KPTN variants were already reported as a loss of function variants. A novel splice site variant in KPTN was detected in two unrelated families of this study. The core phenotype with neurodevelopment delay was present in all patients. However, macrocephaly was not present in at least one patient. In total, two patients exhibited developmental and epileptic encephalopathies with generalized tonic-clonic seizures that were drug-resistant in one of them. Thus, we further delineate the KPTN-related syndrome, especially emphasizing the severity of epilepsy phenotypes and difficulties in treatment in patients of our cohort.

Wireless Heart Sensor for Capturing Cardiac Orienting Response for Prediction of Neurodevelopmental Delay in Infants

Early identification of infants at risk of neurodevelopmental delay is an essential public health aim. Such a diagnosis allows early interventions for infants that maximally take advantage of the neural plasticity in the developing brain. Using standardized physiological developmental tests, such as the assessment of neurophysiological response to environmental events using cardiac orienting responses (CORs), is a promising and effective approach for early recognition of neurodevelopmental delay. Previous CORs have been collected on children using large bulky equipment that would not be feasible for widespread screening in routine clinical visits. We developed a portable wireless electrocardiogram (ECG) system along with a custom application for IOS tablets that, in tandem, can extract CORs with sufficient physiologic and timing accuracy to reflect the well-characterized ECG response to both auditory and visual stimuli. The sensor described here serves as an initial step in determining the extent to which COR tools are cost-effective for the early screening of children to determine who is at risk of developing neurocognitive deficits and may benefit from early interventions. We demonstrated that our approach, based on a wireless heartbeat sensor system and a custom mobile application for stimulus display and data recording, is sufficient to capture CORs from infants. The COR monitoring approach described here with mobile technology is an example of a desired standardized physiologic assessment that is a cost-and-time efficient, scalable method for early recognition of neurodevelopmental delay.

Three de novo variants in KMT2A (MLL) identified by whole exome sequencing in patients with Wiedemann-Steiner syndrome

Background

Wiedemann–Steiner syndrome (WSS) is an autosomal dominant disorder characterized by short stature, hypertrichosis, intellectual disability, developmental delay, along with facial dysmorphism. WSS patients exhibit great phenotypic heterogeneities. Some variants in KMT2A (MLL) gene have been identified as the cause of WSS.

Methods

Whole exome sequencing on the probands followed by Sanger sequencing validations in the family were applied to determine genetic variants. In silico analyses were used for predicting potential effects of the variants.

Results

We identified three novel de novo heterozygous variants: c.883A>T (p.Lys295*), c.4171C>T (p.Gln1391*), and c.3499T>C (p.Cys1167Arg), in KMT2A gene from three unrelated Chinese WSS patients. According to the American College of Medical Genetics and Genomics (ACMG) guidelines, these three variants were classified as pathogenic, pathogenic and likely pathogenic variant, respectively. By reviewing all the available cases with same mutated KMT2A regions as the three patients had, we found that in addition to the representative symptoms, our patients exhibited some sporadically observed symptoms, such as severe ophthalmological symptoms, endocardial fibroelastosis, cytomegalovirus infection, and feet eversion. We also revealed that variants in different KMT2A regions contribute to the phenotypic heterogeneity of WSS, highlighting challenges in the diagnosis of syndromic disorders spanning a broad phenotypic spectrum.

Conclusion

Our study would aid in further broadening our knowledge about the genotype–phenotype correlation of WSS.

Neurodevelopmental outcome of healthy term newborn with serum bilirubin >15 mg/dl at one year

BACKGROUND

Neonatal hyperbilirubinemia is a common medical emergency in early neonatal period. Unconjugated bilirubin is neurotoxic and can lead to lifelong neurological sequelae in survivors.

OBJECTIVE

To find out the association between serum bilirubin and neurodevelopmental outcome at 1 year of age using Development Assessment Scale for Indian Infants (DASII).

METHODS

A prospective cohort study was conducted in the Department of Pediatrics of a tertiary care institution of Central India between January 2018 and August 2019. Total 108 term healthy neonates, with at least one serum bilirubin value of >15 mg/dl, were included. Subjects were divided into three groups based on the serum bilirubin; group 1: (15-20 mg/dl) -85(78.7%) cases, group 2: (20-25 mg/dl) -17(15.7%), and group 3: (>25 mg/dl) -6(5.5%). Developmental assessment was done using DASII at 3, 6, 9, 12 months of age.

RESULTS

Out of 108 cases, 101(93.5%) received phototherapy, and 7(6.5%) received double volume exchange transfusion. Severe delay was observed in 5(4.6%) and mild delay in 2(1.9%) cases in the motor domain of DASII at one year. Severe delay in the motor domain was associated with mean TSB of 27.940±2.89 mg/dl and mild delay with mean TSB of 22.75±1.76 mg/dl (p = 0.001). On cluster analysis, delay was observed in locomotion 1 score in 11(13%) cases (p = 0.003) and manipulation score in 6(7.1%) cases in group 1.

CONCLUSION

Increased serum bilirubin was a significant risk factor for the delayed neurodevelopment in babies with neonatal jaundice. Even a moderate level of bilirubin significantly affects the developmental outcome.