Neuroimaging assessment of pediatric cerebral changes associated with SARS-CoV-2 infection during pregnancy

The association between maternal immune activation and brain structure and function in human offspring: a systematic review

Maternal immune activation (MIA) during pregnancy, as a result of infectious or inflammatory stimuli, has gained increasing attention for its potential role in adverse child neurodevelopment, with studies focusing on associations in children born preterm. This systematic review summarizes research on the link between several types of prenatal MIA and subsequent child structural and/or functional brain development outcomes. We identified 111 neuroimaging studies in five MIA areas: inflammatory biomarkers (n = 13), chorioamnionitis (n = 18), other types of infections (n = 18), human immunodeficiency virus (HIV) (n = 42), and Zika virus (n = 20). Overall, there was large heterogeneity in the type of MIA exposure examined and in study methodology. Most studies had a prospective single cohort design and mainly focused on potential effects on the brain up to one year after birth. The median sample size was 53 participants. Severe infections, i.e., HIV and Zika virus, were associated with various types of cerebral lesions (e.g., microcephaly, atrophy, or periventricular leukomalacia) that were consistently identified across studies. For less severe infections and chronic inflammation, findings were generally inconsistent and mostly included deviations in white matter structure/function. Current findings have been mainly observed in the infants' brain, presenting an opportunity for future studies to investigate whether these associations persist throughout development. Additionally, the inconsistent findings, encompassing both regions of interest and null results, call into question whether prenatal exposure to less severe infections and chronic inflammation exerts a small effect or no effect on child brain development.

Maternal Immune Activation and Child Brain Development: A Longitudinal Population-Based Multimodal Neuroimaging Study

BACKGROUND

Maternal immune activation (MIA) has been hypothesized to have an adverse effect on child neurodevelopment, but only a few neuroimaging studies have been performed to date, mostly in neonates. In this population-based cohort study, we investigated the association between MIA and multiple neuroimaging modalities depicting brain development from childhood to adolescence.

METHODS

We used data of mother-child pairs from the Generation R Study. To define our exposure, we measured interleukin (IL) 1β, IL-6, IL-17a, IL-23, interferon gamma, and C-reactive protein at 2 time points during pregnancy. Because levels of these 5 cytokines were highly correlated, we were able to compute a cytokine index. We used multiple brain imaging modalities as outcomes, including global and regional measures of brain morphology (structural magnetic resonance imaging, volume; n = 3295), white matter microstructure (diffusion magnetic resonance imaging, fractional anisotropy and mean diffusivity; n = 3267), and functional connectivity (functional magnetic resonance imaging, graph theory measures, and network-level connectivity; n = 2914) in the children at ages 10 and 14 years. We performed mixed effects models using child's age as a continuous time variable.

RESULTS

We found no significant effect of time on any neuroimaging outcomes in children over time, and there was no time × MIA interaction. These associations were similar for the cytokine index, C-reactive protein, and individual cytokines. We observed no evidence for differential effects of timing of prenatal MIA or child sex after multiple testing correction.

CONCLUSIONS

In this longitudinal population-based study, we found no evidence for an association between MIA and child brain development in the general population. Our findings differ from previous research in neonates that have shown structural and functional brain abnormalities after MIA.

Cranial ultrasonographic findings in newborns exposed to SARS-CoV-2: a single-centre cross-sectional analysis

BACKGROUND

SARS-CoV-2's potential consequences on the developing brain are still unknown. The aim of this study was to describe cranial ultrasonographic (cUS) findings in a population of newborns exposed to SARS-CoV-2 born at San Marco Hospital in Catania.

METHODS

Two cohort of newborns, one exposed to SARS-CoV-2 both during gestation and at birth and one unexposed, were enrolled in this cross-sectional study conducted according to the STROBE guidelines (Strenghtening the Reporting of Observational Studies in Epidemiology) and underwent cUS. We performed a statistical analysis using the Fisher's exact test to assess whether significant differences among the two groups existed.

RESULTS

we enrolled 139 exposed newborns (62 females, 77 males with median gestational age 38.4 ± 1.9 W and median weight at birth 3142.8 ± 594.4 g) and 139 unexposed newborns (60 females, 79 males with median gestational age 38,9 ± 1.3 W and median weight at birth 3230 ± 336 g). cUS abnormalities were found in 32 exposed patients (23%) and in 23 (16.5%) unexposed patients. A statistically significant difference was found in the incidence of minor intracranial abnormalities (p 0.036) between exposed and unexposed patients and between newborns exposed during pregnancy and unexposed patients (p 0.016).

CONCLUSIONS

in our experience, the incidence of minor intracranial abnormalities was higher in SARS-COV-2-exposed newborns. Our results must be taken with caution and need further confirmation in larger studies but suggest to consider performing cUS at birth in newborns exposed to SARS-CoV-2 in research contexts.

Mechanobiological insight into brain diseases based on mechanosensitive channels: Common mechanisms and clinical potential

BACKGROUND

As physical signals, mechanical cues regulate the neural cells in the brain. The mechanosensitive channels (MSCs) perceive the mechanical cues and transduce them by permeating specific ions or molecules across the plasma membrane, and finally trigger a series of intracellular bioelectrical and biochemical signals. Emerging evidence supports that wide-distributed, high-expressed MSCs like Piezo1 play important roles in several neurophysiological processes and neurological disorders.

AIMS

To systematically conclude the functions of MSCs in the brain and provide a novel mechanobiological perspective for brain diseases.

METHOD

We summarized the mechanical cues and MSCs detected in the brain and the research progress on the functional roles of MSCs in physiological conditions. We then concluded the pathological activation and downstream pathways triggered by MSCs in two categories of brain diseases, neurodegenerative diseases and place-occupying damages. Finally, we outlined the methods for manipulating MSCs and discussed their medical potential with some crucial outstanding issues.

RESULTS

The MSCs present underlying common mechanisms in different brain diseases by acting as the "transportation hubs" to transduce the distinct signal patterns: the upstream mechanical cues and the downstream intracellular pathways. Manipulating the MSCs is feasible to alter the complicated downstream processes, providing them promising targets for clinical treatment.

CONCLUSIONS

Recent research on MSCs provides a novel insight into brain diseases. The common mechanisms mediated by MSCs inspire a wide range of therapeutic potentials targeted on MSCs in different brain diseases.

Insights Into MRI Neuroimaging Patterns of COVID-19 in Children: A Retrospective Comprehensive Analysis

RATIONALE AND OBJECTIVES

Neurological complications associated with coronavirus disease (COVID-19) have been reported in children; however, data on neuroimaging findings remain limited. This study aimed to comprehensively examine neuroimaging patterns of COVID-19 in children and their relationship with clinical outcomes.

MATERIALS AND METHODS

This retrospective cross-sectional study involved reviewing the medical records and MRI scans of 95 children who developed new neurological symptoms within 2-4 weeks of clinical and laboratory confirmation of COVID-19. Patients were categorized into four groups based on guidelines approved by the Centers for Disease Control and Prevention (CDC). Initial brain/spinal MRI was performed. Images were reviewed by three blinded radiologists, and the findings were analyzed and categorized based on the observed patterns in the brain and spinal cord. Follow-up MRI was performed and analyzed to track lesion progression.

RESULTS

Encephalopathy was the most common neurological symptom (50.5%). The most common initial MRI involvement patterns were non-confluent multifocal hyperintense white matter (WM) lesions (36.8%) and ischemia (18.9%). Most patients who underwent follow-up MRI (n = 56) showed complete resolution (69.9%); however, some patients developed encephalomalacia and myelomalacia (23.2% and 7.1%, respectively). Non-confluent hyperintense WM lesions were associated with good outcomes (45.9%, P = 0.014), whereas ischemia and hemorrhage were associated with poor outcomes (44.1%, P < 0.001).

CONCLUSION

This study revealed diverse neuroimaging patterns in pediatric COVID-19 patients. Non-confluent WM lesions were associated with good outcomes, whereas ischemia and hemorrhage were associated with poorer prognoses. Understanding these patterns is crucial for their early detection, accurate diagnosis, and appropriate management.

How Much Does SARS-CoV-2 Infection during Pregnancy Affect the Neonatal Brain, Heart, and Kidney? A Parallel between COVID-19, Vaccination, and Normal Pregnancy

During the last decades, a growing number of studies have shown that infections during pregnancy have an important impact on both pregnant women and their fetuses. Our goal was to include newborns from pregnancies with SARS-CoV-2 infection and to investigate the extension of neonatal complications using cardiac, abdominal, and cerebral ultrasonography; hearing testing; and indirect ophthalmoscopy. Likewise, neonates whose mothers were vaccinated against COVID-19 during pregnancy and those from pathology-free pregnancies were examined. A total of 458 mother-newborn dyads were included over a period of 10 months and divided into three groups: the COVID-19 group, vaccine group, and control group. Although six cardiac malformations were found in the COVID-19 group, no correlation was made compared to the vaccine and control group (p = 0.07). Grade 1 intraventricular hemorrhage and hypoxic ischemic encephalopathy were the most prevalent among neonates from mothers with SARS-CoV-2 infection (p = 0.002 and p < 0.001, respectively). The kidney anomaly found to be most frequent in this group was grade 1 unilateral hydronephrosis (p < 0.001). COVID-19 disease during the gestational period had no effect on the auditory or visual function. Our findings highlight the importance of implementing proper infection control practices for future mothers, and by continuing to investigate this topic, we can gather valuable insights that will improve neonatal health in this context.