[Congenital cytomegalovirus infection and cortical/subcortical malformations]

Updating an Overview of Teratology

In this chapter, the authors aim to update an overview of the principles of teratology, beginning with the definition of teratology, the critical point at which this process occurs, and some of the most common etiological agents that improve our understanding of teratology.Modern teratology has greatly improved in recent years with advances in new methods in molecular biology, toxicology, animal laboratory science, and genetics, increasing our knowledge of ambient influences. Nevertheless, there is a lot to do to reduce the influence of hazardous intervening agents, whether they target our genetics or not, that can negatively affect pregnancy and induce congenital development disorders, including morphological, biochemical, or behavioral defects.Certain agents might indeed be related to certain defects, but we have not been able to identify the cause of most congenital defects, which highlights the importance of finding and testing out new genetics techniques and conducting laboratory animal science to unravel the etiology and pathogenicity of each congenital defect.

Effect of neonatal neuronal intensive care unit on neonatal encephalopathy

Prophylaxis of brain injury in newborns has been a main concern since the first neonatal neuronal intensive care unit (NNICU) was established in the world in 2008. The aim of this study was to outline and evaluate the unit’s development by analyzing the demographics of the patients, the services delivered, the short-term outcomes before and after the establishment of NNICU. During the two investigation periods, 384 newborns were diagnosed or suspected as “neonatal encephalopathy”, among which 185 patients admitted to NNICU between 2011.03.01 and 2012.09.30 before the establishment of NNICU were enrolled in the pre-NNICU group, another 199 neonates hospitalized during 2018.03.01 to 2019.09.30 were included in the post-NNICU group. Patients in the post-NNICU group were more likely to have seizures (P = 0.001), incomplete or absent primitive reflexes (P = 0.002), therapeutic hypothermia (P<0.001) and liquid control (P<0.001) in acute phase. Meanwhile, amplitude-integrated electro encephalogram (aEEG) monitoring (P<0.001) and cranial ultrasound (P<0.001) were more often used in NNICU. Both of the follow-up rate in brain MRI and the assessment of neurodevelopment at 3 months were higher in the post-NNICU group (P<0.001). In conclusion, the NNICU focused on the neonatal neurocritical care for the babies susceptible to NE with the guidance of evidence-based medicine, the establishment of NNICU is gradually improving and standardizing the neuroprotective therapy and clinical follow-up to improve neurodevelopmental prognosis of the NE patients in CHCMU.

Unilateral right closed-lip schizencephaly

Schizencephaly is a rare central nervous system (CNS) malformation secondary to neuronal migration defects. The pathogenesis is complex and is secondary to environmental and genetic factors. Clinically, the majority of patients present with varying degrees of motor and psychological disturbances. Imaging plays a cornerstone in the diagnosis by identifying the characteristic lesional features and recognising other associated abnormalities such as an absent septum pellucidum and corpus callosum dysgenesis. Here, we present a male paediatric case who presented with an interestingly asymptomatic unilateral right closed-lip schizencephaly and review the aetiology, clinical presentation and imaging characteristics of the disease and associated literature.

Congenital human cytomegalovirus infection and neurologic diseases in newborns

Objective:

This review aimed to summarize research progress regarding congenital cytomegalovirus (cCMV) infection-related nervous system diseases and their mechanisms.

Data sources:

All literature quoted in this review was retrieved from PubMed and Web of Science using the keywords “Cytomegalovirus” and “Neurologic disease” in English. To identify more important information, we did not set time limits.

Study selection:

Relevant articles were selected by carefully reading the titles and abstracts. Then, different diagnosis and clinical treatment methods for human CMV infection-related neurologic diseases were compared, and the main mechanism and pathogenesis of neurologic damage caused by CMV were summarized from the selected published articles.

Results:

cCMV infection is a major cause of neonatal malformation. cCMV can infect the fetal encephalon during early gestation and compromise neurodevelopment, resulting in varying degrees of neurologic damage, mainly including hearing impairment, central nervous system (CNS) infection, neurodevelopmental disorders, ophthalmic complications, cerebral neoplasms, infantile autism, epilepsy, and other neurologic abnormalities.

Conclusions:

cCMV infection-induced neurodevelopmental abnormalities, which were directly caused by fetal encephalon infection, thus inducing neuroimmune responses to damage nerve cells. Such abnormalities were also caused by suppression of the proliferation and differentiation of neural progenitor cells by CMV's gene products. cCMV infection in the fetal encephalon can also inhibit neuronal migration and synapse formation and indirectly trigger placental inflammation and thus disrupt the oxygen supply to the fetus.

DISTURBANCE OF THE PROGESTERONE AND ITS METABOLITES SYNTHESIS IN THE DEVELOPMENT OF NEUROLOGICAL DISORDERS IN CHILDREN AFTER CYTOMEGALOVIRUS INFECTION DURING PREGNANCY

Cytomegalovirus (CMV) infection is one of the causes of congenital neurological disorders and the virus itself is the most common viral  agent causing an imbalance in the production of placenta  progesterone and its neuroactive metabolites – allopregnenolone and 5α-dihydroprogesterone. The aim was to evaluate the concentration  of progesterone and its metabolites – 5α-dihydroprogesterone and  allopregnenolone – in placenta during exacerbation of CMV infection  in the first trimester of pregnancy, and the impact of these  disturbances on the development of neurological disorders in children. We examined 30 pregnant women with exacerbation of  CMV infection in the first trimester of pregnancy and 30 pregnant  women with latent disease; and later their newborns. The enzyme  immunoassay was used to determine  concentration of progesterone  in placenta; the histochemical method – to determine 5α-dihydroprogesterone and allopregnenolone. Newborns underwent  neurosonography studies. Exacerbation of CMV infection in the first  trimester of pregnancy decreased progesterone in placenta by 1.3  times, 5α-dihydroprogesterone – by 1.73 times and allopregnenolone – by 2 times. Ultrasound examination of the brain  showed ventriculomegaly, periventricular ischemia, and pseudocysts  in newborns up to one year from mothers with exacerbation of CMV  during pregnancy. Later, minimal brain dysfunctions were manifested by motor disorders, increased general, vegetative excitability, and a  tendency to digestive and sleep disorders. The data obtained  indicate that the exacerbation of CMV infection in the first trimester  of pregnancy is interrelated with a decrease in the concentration of progesterone and its metabolites (5α-dihydroprogesterone, allopregnenolone) in the placenta and development of neurological dysfunction in newborns.

Screening for seemingly healthy newborns with congenital cytomegalovirus infection by quantitative real-time polymerase chain reaction using newborn urine: an observational study

OBJECTIVE

Approximately 8-10% of newborns with asymptomatic congenital cytomegalovirus (cCMV) infection develop sensorineural hearing loss (SNHL). However, the relationship between CMV load, SNHL and central nervous system (CNS) damage in cCMV infection remains unclear. This study aimed to examine the relationship between urinary CMV load, SNHL and CNS damage in newborns with cCMV infection.

STUDY DESIGN

The study included 23 368 newborns from two maternity hospitals in Saitama Prefecture, Japan. Urine screening for cCMV infection (quantitative real-time PCR) and newborn hearing screening (automated auditory brainstem response (AABR) testing) were conducted within 5 days of birth to examine the incidence of cCMV infection and SNHL, respectively. CNS damage was assessed by MRI of cCMV-infected newborns.

RESULTS

The incidence of cCMV infection was 60/23 368 (0.257%; 95% CI 0.192% to 0.322%). The geometric mean urinary CMV DNA copy number in newborns with cCMV was 1.79×10⁶ copies/mL (95% CI 7.97×10⁵ to 4.02×10⁶). AABR testing revealed abnormalities in 171 of the 22 229 (0.769%) newborns whose parents approved hearing screening. Of these 171 newborns, 22 had SNHL (12.9%), and 5 of these 22 were infected with cCMV (22.7%). Newborns with both cCMV and SNHL had a higher urinary CMV DNA copy number than newborns with cCMV without SNHL (p=0.036). MRI revealed CNS damage, including white matter abnormalities, in 83.0% of newborns with cCMV. Moreover, newborns with CNS damage had a significantly greater urinary CMV load than newborns without CNS damage (p=0.013).

CONCLUSIONS

We determined the incidence of cCMV infection and urinary CMV DNA copy number in seemingly healthy newborns from two hospitals in Saitama Prefecture. SNHL and CNS damage were associated with urinary CMV DNA copy number. Quantification of urinary CMV load may effectively predict the incidence of late-onset SNHL and neurodevelopmental disorders.