Apparent diffusion coefficient values of the white matter in magnetic resonance imaging of the neonatal brain may help predict outcome in congenital cytomegalovirus infection

BACKGROUND

White matter change is a well-known abnormality in congenital cytomegalovirus (cCMV) infection, but grading remains challenging and clinical relevance unclear.

OBJECTIVE

To investigate if quantitative measurement of white matter apparent diffusion coefficient (ADC) values in magnetic resonance imaging (MRI) of the neonatal brain can predict outcome in cCMV.

MATERIALS AND METHODS

A retrospective, single-center observational study, including patients with cCMV who had a neonatal brain MRI with diffusion-weighted imaging, was performed between 2007 and 2020. Regions of interest were systematically placed in the white matter on the ADC maps. Two pediatric radiologists independently scored additional brain abnormalities. Outcome measures were neonatal hearing and cognitive and motor development. Statistical analysis included simple and penalized elastic net regression.

RESULTS

Neonatal brain MRI was evaluated in 255 patients (median age 21 days, 25-75 percentiles: 14-28 days, 121 male). Gyral abnormalities were noted in nine patients (3.5%), ventriculomegaly in 24 (9.4%), and subependymal cysts in 58 (22.7%). General white matter ADC was significantly higher in patients with neonatal hearing loss and cognitive and motor impairment (P< 0.05). For neonatal hearing loss, simple logistic regression using only general white matter was the best prediction model, with a receiver operating characteristic area under the curve (AUC)=0.76. For cognitive impairment, interacting elastic net regression, including other brain abnormalities and frontoparietal white matter ADC, performed best, with AUC=0.89. For motor impairment, interacting elastic net regression, including other brain abnormalities and deep anterior frontal white matter performed best, with AUC=0.73.

CONCLUSION

Neonatal white matter ADC was significantly higher in patients with clinical impairments. Quantitative ADC measurement may be a useful tool for predicting clinical outcome in cCMV.

ATP2B2 de novo variants as a cause of variable neurodevelopmental disorders that feature dystonia, ataxia, intellectual disability, behavioral symptoms, and seizures

PURPOSE

ATP2B2 encodes the variant-constrained plasma-membrane calcium-transporting ATPase-2, expressed in sensory ear cells and specialized neurons. ATP2B2/Atp2b2 variants were previously linked to isolated hearing loss in patients and neurodevelopmental deficits with ataxia in mice. We aimed to establish the association between ATP2B2 and human neurological disorders.

METHODS

Multinational case recruitment, scrutiny of trio-based genomics data, in silico analyses, and functional variant characterization were performed.

RESULTS

We assembled 7 individuals harboring rare, predicted deleterious heterozygous ATP2B2 variants. The alleles comprised 5 missense substitutions that affected evolutionarily conserved sites and 2 frameshift variants in the penultimate exon. For 6 variants, a de novo status was confirmed. Unlike described patients with hearing loss, the individuals displayed a spectrum of neurological abnormalities, ranging from ataxia with dystonic features to complex neurodevelopmental manifestations with intellectual disability, autism, and seizures. Two cases with recurrent amino-acid variation showed distinctive overlap with cerebellar atrophy-associated ataxia and epilepsy. In cell-based studies, all variants caused significant alterations in cytosolic calcium handling with both loss- and gain-of-function effects.

CONCLUSION

Presentations in our series recapitulate key phenotypic aspects of Atp2b2-mouse models and underline the importance of precise calcium regulation for neurodevelopment and cerebellar function. Our study documents a role for ATP2B2 variants in causing heterogeneous neurodevelopmental and movement-disorder syndromes.

Neurodevelopmental outcome in children with congenital cytomegalovirus infection: A prospective multicenter cohort study

BACKGROUND

Congenital cytomegalovirus infection (cCMV) is the most common congenital infection worldwide and is a major cause of neurodevelopmental impairment in children. At this point there are insufficient data on neurodevelopmental outcome of children with cCMV, both symptomatic and asymptomatic.

AIM

This study aimed to describe the neurodevelopmental outcome in a large prospective cohort of children with cCMV.

METHODS

All children with cCMV, included in the Flemish cCMV register, were eligible for this study. Data on neurodevelopmental outcome was available in 753 children. Data on neuromotor, cognitive, behavioral, audiological and ophthalmological outcome were analyzed.

RESULTS

Neurodevelopmental outcome was normal in 530/753 (70,4 %) at any age of last follow-up. Mild, moderate and severe neurodevelopmental impairment was found in 128/753 (16,9 %), 56/753 (7,4 %) and 39/753 (5,2 %), respectively. Adverse outcome is found both in the symptomatic and asymptomatic children (53,5 % versus 17,8 %). Autism spectrum disorder (ASD) was diagnosed more often than in the general population in Flanders (2,5 % versus 0,7 %). Speech and language impairment was found in 2 %, even in absence of hearing loss.

CONCLUSION

Both symptomatic and asymptomatic cCMV children are at risk of sequelae, with higher risk in case of first trimester infection. During follow-up of this population, special attention should be given to the audiological follow-up, the presence of hypotonia at young age, the possible higher risk of ASD and the risk of speech and language impairment even in absence of hearing loss. Our results emphasize the need for multidisciplinary neurodevelopmental follow-up of all cCMV infected children.

Antenatal corticosteroids-to-birth interval in preterm birth

Objectives: The purpose of this study was to compare short-term outcomes in children born between 24 and 34 weeks' gestation, according to observed antenatal corticosteroids (ACS)-to-birth intervals. Research question: 'Is there a difference in short-term outcomes between observed ACS-to-birth intervals across a range of gestational ages at birth?'Methods: Cohort study assessing differences in incidence of short-term neonatal outcomes according to the observed interval between the last administration of ACS and birth. Linear, non-weighted GEE models with an independence working correlation structure were fitted to infant level data providing valid point estimates for either incidence or rate differences (binary outcomes) or average differences (continuous outcomes).Results: Of 886 children, 35.9% were born within 2 days after the last administration of ACS, 32.2% within 2 to 7 days, 14.1% within 8 to 14 days, and 17.8% more than 14 days after. Across gestational ages at birth, there were no differences in birth weight between children born at an ACS-to-birth interval of 7 days or less compared to more than 7 days, nor were there differences in respiratory outcomes, cerebral outcomes, or composite outcome.Conclusion: Drawing conclusions on the importance of the ACS-to-birth interval is difficult due to the post-hoc nature of the variable. In the absence of tools to better estimate if and when PTB will occur, it might not have any value in daily practice, regardless of whether there is an optimal ACS-to-birth interval or not.

Phenotypic spectrum of the RBM10-mediated intellectual disability and congenital malformation syndrome beyond classic TARP syndrome features

Pathogenic variants in the RBM10 gene cause a rare X-linked disorder described as TARP (Talipes equinovarus, Atrial septal defect, Robin sequence, and Persistent left vena cava superior) syndrome. We report two novel patients with truncating RBM10 variants in view of the literature, presenting a total of 26 patients from 15 unrelated families. Our results illustrate the highly pleiotropic nature of RBM10 pathogenic variants, beyond the classic TARP syndrome features. Major clinical characteristics include severe developmental delay, failure to thrive, brain malformations, neurological symptoms, respiratory issues, and facial dysmorphism. Minor features are growth retardation, cardiac, gastrointestinal, limb, and skeletal abnormalities. Additional recurrent features include genital and renal abnormalities as well as hearing and visual impairment. Thus, RBM10 loss of function variants typically cause an intellectual disability and congenital malformation syndrome that requires assessment of multiple organ systems at diagnosis and for which provided clinical features might simplify diagnostic assessment. Furthermore, evidence for an RBM10-related genotype-phenotype correlation is emerging, which can be important for prognosis.

Predictability of cerebral palsy in a high-risk NICU population

AIM

This study aims to create a predictive model for the assessment of the individual risk of developing cerebral palsy in a large cohort of selected high-risk infants.

PATIENTS AND METHODS

1099 NICU-admitted high-risk infants were assessed up to the corrected age of at least 12 months. CP was categorized relative to subtype, distribution and severity. Several perinatal characteristics (gender, gestational age, multiple gestation, small for gestational age, perinatal asphyxia and duration of mechanical ventilation), besides neonatal cerebral ultrasound data were used in the logistic regression model for the risk of CP.

RESULTS

Perinatal asphyxia, mechanical ventilation>7 days, white matter disease except for transient echodensities<7 days, intraventricular haemorrhage grades III and IV, cerebral infarction and deep grey matter lesions were recognized as independent predictors for the development of CP. 95% of all children with CP were correctly identified at or above the cut-off value of 4.5% probability of CP development. Higher gestational age, perinatal asphyxia and deep grey matter lesion are independent predictors for non-spastic versus spastic CP (OR=1.1, 3.6, and 7.5, respectively). Independent risk factors for prediction of unilateral versus bilateral spastic CP are higher gestational age, cerebral infarction and parenchymal haemorrhagic infarction (OR=1.2, 31, and 17.6, respectively). Perinatal asphyxia is the only significant variable retained for the prediction of severe CP versus mild or moderate CP.

CONCLUSION

The presented model based on perinatal characteristics and neonatal US-detected brain injuries is a useful tool in identifying specific infants at risk for developing CP.

Further delineation of the 15q13 microdeletion and duplication syndromes: a clinical spectrum varying from non-pathogenic to a severe outcome

BACKGROUND

Recurrent 15q13.3 microdeletions were recently identified with identical proximal (BP4) and distal (BP5) breakpoints and associated with mild to moderate mental retardation and epilepsy.

METHODS

To assess further the clinical implications of this novel 15q13.3 microdeletion syndrome, 18 new probands with a deletion were molecularly and clinically characterised. In addition, we evaluated the characteristics of a family with a more proximal deletion between BP3 and BP4. Finally, four patients with a duplication in the BP3-BP4-BP5 region were included in this study to ascertain the clinical significance of duplications in this region.

RESULTS

The 15q13.3 microdeletion in our series was associated with a highly variable intra- and inter-familial phenotype. At least 11 of the 18 deletions identified were inherited. Moreover, 7 of 10 siblings from four different families also had this deletion: one had a mild developmental delay, four had only learning problems during childhood, but functioned well in daily life as adults, whereas the other two had no learning problems at all. In contrast to previous findings, seizures were not a common feature in our series (only 2 of 17 living probands). Three patients with deletions had cardiac defects and deletion of the KLF13 gene, located in the critical region, may contribute to these abnormalities. The limited data from the single family with the more proximal BP3-BP4 deletion suggest this deletion may have little clinical significance. Patients with duplications of the BP3-BP4-BP5 region did not share a recognisable phenotype, but psychiatric disease was noted in 2 of 4 patients.

CONCLUSIONS

Overall, our findings broaden the phenotypic spectrum associated with 15q13.3 deletions and suggest that, in some individuals, deletion of 15q13.3 is not sufficient to cause disease. The existence of microdeletion syndromes, associated with an unpredictable and variable phenotypic outcome, will pose the clinician with diagnostic difficulties and challenge the commonly used paradigm in the diagnostic setting that aberrations inherited from a phenotypically normal parent are usually without clinical consequences.

Prevalence, type, distribution, and severity of cerebral palsy in relation to gestational age: a meta-analytic review

The aim of this review is to determine the relationship between gestational age (GA) and prevalence, type, distribution, and severity of cerebral palsy (CP). Epidemiological studies with cohorts expressed by GA were assessed. A comprehensive meta-analysis and meta-regression was performed on four fetal age categories. Studies of children with CP as a target population were added. Twenty-six articles met the inclusion criteria. The prevalence of CP decreases significantly with increasing GA category: 14.6% at 22 to 27 weeks' gestation, 6.2% at 28 to 31 weeks, 0.7% at 32 to 36 weeks, and 0.1% in term infants. Interestingly, a significant decrease in prevalence of CP starts only from a GA of 27 weeks onwards. In preterm infants, spastic CP is predominant. In term infants, the non-spastic form of CP is more prevalent than in preterm infants. Bilateral spastic CP is most prevalent in both preterm and term infants. However, the proportion of unilateral spastic CP in term infants is substantial. No relationship could be detected between severity of CP and GA. There is a strong need for an international, well-described, and generally accepted classification system for subtypes and severity of CP.

Visual contribution to walking in children with Developmental Coordination Disorder

BACKGROUND

The motor co-ordination problems of children with Developmental Coordination Disorder (DCD) have been frequently associated with poor visuospatial processing. In order to extend these findings mainly based on fine motor experiments, the present study investigates the contribution of vision to the control of walking in children with DCD.

METHODS

Children with DCD (n = 12) walked at their preferred speed on a straight, firm and uncluttered walkway in a condition with normal lighting and in a dark condition. Spatiotemporal gait variables were assessed by means of a three-dimensional ProReflex camera system and compared with the gait pattern of matched, typically developing (TD) children (n = 12).

RESULTS

In normal lighting, the gait pattern of both groups was similar, with the exception of subtle differences in the temporal phasing, showing a slightly longer support phase in the children with DCD. In the dark, step frequency and step length were decreased in the children with DCD, resulting in a significantly slower walking velocity. In addition, the medio-lateral excursion of the centre of mass tended to increase in this group. In the TD children, adaptations to the spatiotemporal pattern remained absent.

CONCLUSIONS

These results suggest that children with DCD are more dependent on global visual flow information than TD children for the maintenance of balance and the control of velocity during walking. This increased dependency on visual control might be associated with a poorly developed internal sensorimotor model.

Neonatal infarction within basal cerebral vein territory

In this report, an unusual intracranial haemorrhage in a term male infant born to a mother with diabetes is explained on the basis of occlusion of both basal veins of Rosenthal. This diagnosis relies on anatomical location and iconographic aspect of the clots. Evidence that this vessel is occluded cannot be ascertained from ultrasound or MR angiographic techniques in the neonatal period. The basal vein has not been implicated in previous reports of neonatal brain haemorrhage.

Perinatal cortical infarction within middle cerebral artery trunks

AIM

To define neonatal pial middle cerebral artery infarction.

METHODS

A retrospective study was made of neonates in whom focal arterial infarction had been detected ultrasonographically. A detailed study was made of cortical middle cerebral artery infarction subtypes.

RESULTS

Forty infarctions, with the exception of those in a posterior cerebral artery, were detected ultrasonographically over a period of 10 years. Most were confirmed by computed tomography or magnetic resonance imaging. Factor V Leiden heterozygosity was documented in three. The onset was probably antepartum in three, and associated with fetal distress before labour in one. There were 19 cases of cortical middle cerebral artery stroke. The truncal type (n=13) was more common than complete (n = 5) middle cerebral artery infarction. Of six infarcts in the anterior trunk, four were in term infants and five affected the right hemisphere. Clinical seizures were part of the anterior truncal presentation in three. One of these infants, with involvement of the primary motor area, developed a severe motor hemisyndrome. The Bayley Mental Developmental Index was above 80 in all of three infants tested with anterior truncal infarction. Of seven patients with posterior truncal infarction, six were at or near term. Six of these lesions were left sided. Clinical seizures were observed in three. A mild motor hemisyndrome developed in at least three of these infants due to involvement of parieto-temporal non-primary cortex.

CONCLUSIONS

Inability to differentiate between truncal and complete middle cerebral artery stroke is one of the explanations for the reported different outcomes. Severe motor hemisyndrome can be predicted from neonatal ultrasonography on the basis of primary motor cortex involvement. Clinical seizures were recognised in less than half of the patients with truncal infarction; left sided presentation was present in the posterior, but not the anterior truncal type of infarction. Asphyxia is a rare cause of focal arterial infarction.

Neonatal focal temporal lobe or atrial wall haemorrhagic infarction

AIMS

To describe two variants of infarction within the temporal lobe, associated with local matrix bleeding and mild to moderate intraventricular haemorrhage.

METHODS

The files of 10 neonates, extracted from a sonographic study of 560 very low birthweight infants conducted between 1993 and 1997, were retrospectively examined.

RESULTS

Seven lesions were located in the middle to posterior area of the temporal lobe, three others faced the atrium. All except two of those with a temporal site were VLBW infants with hyaline membrane disease. Except for one fatal case, intraventricular bleeding was mild to moderate. Computed tomograms or magnetic resonance imaging were used to illustrate the haemorrhagic nature of three lesions. Survivors of this so far undescribed entity who were followed up for more than 18 months did not have a uniform type of cerebral palsy but some scored in the low normal range on the Bayley Mental Development Index. One girl developed temporal lobe epilepsy.

CONCLUSIONS

This pattern of injury seems to be one of venous infarction associated with temporal or para-atrial matrix haemorrhage. The temporal site fits the picture of venous infarction within the area drained by the inferior ventricular vein. A less constant lateral atrial vein, either draining into the basal or internal cerebral vein, is probably involved in the para-atrial lesion. Sonography may be the only practical tool currently available for detection in life.

On the variability of the Brachmann-de Lange syndrome in seven patients

The results of the clinical and radiographic study of 7 patients support the view of a unimodal and rather narrow phenotypic spectrum in the Brachmann-de Lange syndrome (BDLS) and reject the existence of a "classic" type of patient and a "mild phenotype" without upper limb defects who survive with moderate to severe mental retardation. Similarity among all patients is greater than their phenotypic differences. Strict clinical definition of the syndrome warrants easier access to the still unknown cause, most probably a single gene mutation with autosomal dominant inheritance.