Congenital cytomegalovirus infections

Human cytomegalovirus infection impairs neural differentiation via repressing sterol regulatory element binding protein 2-mediated cholesterol biosynthesis

Congenital human cytomegalovirus (HCMV) infection is a major cause of abnormalities and disorders in the central nervous system (CNS) and/or the peripheral nervous system (PNS). However, the complete pathogenesis of neural differentiation disorders caused by HCMV infection remains to be fully elucidated. Stem cells from human exfoliated deciduous teeth (SHEDs) are mesenchymal stem cells (MSCs) with a high proliferation and neurogenic differentiation capacity. Since SHEDs originate from the neural crest of the early embryonic ectoderm, SHEDs were hypothesized to serve as a promising cell line for investigating the pathogenesis of neural differentiation disorders in the PNS caused by congenital HCMV infection. In this work, SHEDs were demonstrated to be fully permissive to HCMV infection and the virus was able to complete its life cycle in SHEDs. Under neurogenic inductive conditions, HCMV infection of SHEDs caused an abnormal neural morphology. The expression of stem/neural cell markers was also disturbed by HCMV infection. The impairment of neural differentiation was mainly due to a reduction of intracellular cholesterol levels caused by HCMV infection. Sterol regulatory element binding protein-2 (SREBP2) is a critical transcription regulator that guides cholesterol synthesis. HCMV infection was shown to hinder the migration of SREBP2 into nucleus and resulted in perinuclear aggregations of SREBP2 during neural differentiation. Our findings provide new insights into the prevention and treatment of nervous system diseases caused by congenital HCMV infection.

Congenital Cytomegalovirus Infection With Isolated "Minor" Lesions at Fetal Magnetic Resonance Imaging: Long-Term Neurological Outcome

BACKGROUND

The prognostic relevance of fetal/early postnatal magnetic resonance (MR) imaging (MRI) isolated "minor" lesions in congenital cytomegalovirus (CMV) infection is still unclear, because of the heterogeneity of previously reported case series. The aim of this study was to report the imaging and long-term clinical follow-up data on a relatively large cohort of infected fetuses.

METHODS

Among 140 CMV-infected fetuses from a single-center 12-year-long fetal MRI database, cases that showed isolated "minor" lesions at MRI, mainly represented by polar temporal lesions, were selected. MRI features were described, and clinical follow-up information was collected through consultation of medical records and telephone interview to establish the auditory and neurological outcome of each patient.

RESULTS

Thirty-six cases were included in the study. The frequency of "minor" lesions increased progressively with ongoing gestational age in cases who underwent serial MR examination; 31% of cases were symptomatic at birth for unilateral altered auditory brainstem response. At long-term clinical follow-up, performed in 35 patients at a mean age of 64.5 months (range: 25 to 138), 43% of patients were asymptomatic and 57% presented with mild/moderate disability including hearing loss (34%), unilateral in all cases but one (therefore classified as severe), and/or minor cognitive and behavioral disorders (49%).

CONCLUSIONS

Descriptive analysis of the type and modality of occurrence of "minor" lesions suggests performing serial fetal/postnatal MR examinations not to miss later-onset lesions. Follow-up data from the present cohort, combined with maternal/fetal factors and serologic-laboratory parameters may contribute to improve prenatal and neonatal period counselling skills.

Pulmonary Complications of Cytomegalovirus Infection in Neonates and Infants: A Systematic Review of Case Reports and Pooled Analysis

BACKGROUND

Cytomegalovirus (CMV) causes intrauterine infections in 0.67% of neonates, with 12.7% displaying symptoms at birth. CMV can lead to severe multiorgan involvement, and mortality in symptomatic cases is around 30%. Pulmonary complications are rare in infants with CMV. This review assesses pulmonary complications and outcomes in infants with CMV infection.

METHODS

A systematic literature search was conducted using PubMed, SCOPUS and Ovid SP to retrieve case reports on pulmonary complications in infants with congenital or perinatal CMV infection. Descriptive analysis and pooled analysis were conducted for the case reports.

RESULTS

A total of 28 articles with 38 patients were included in this systematic review. The reported pulmonary complications in the case reports were CMV pneumonitis (34.2%), persistent pulmonary hypertension of the newborn (18.4%), emphysema and chronic lung disease (15.8%), diaphragmatic dysfunction (13.2%), lung cysts and calcifications (10.5%), Pneumocystis jirovecii infection (7.9%), pulmonary hypoplasia (5.3%) and bronchial atresia (2.6%). Seven (18.4%) of 38 patients passed away because of the pulmonary complications of CMV infection. Congenital transmission ( P = 0.0108), maternal CMV ( P = 0.0396) and presence of neonatal comorbidities ( P = 0.0398) were independent risk factors for mortality.

CONCLUSIONS

This systematic review demonstrated infrequent occurrence of severe pulmonary involvement in CMV infection but should be considered in infants with persistent or severe respiratory symptoms.

Long-term linguistic outcome in adults with congenital cytomegalovirus infection

BACKGROUND

Congenital cytomegalovirus (cCMV) is the most common prenatal infection and the main infectious cause of neurodevelopmental abnormalities in developed countries. Long-term neuropsychological outcome of cCMV infection is still not well understood. This is the first study that presents linguistic follow-up data performed on adults who were infected in utero.

METHOD

All individuals from a universal newborn CMV screening study in Sweden sampled from 1977 to 1985 were invited to participate in a follow-up study. 34/71 persons (48%) with cCMV and 22/46 controls (48%) were enrolled. Participants were between 34 and 43 years. Linguistic ability was evaluated with two-word fluency tasks (FAS letter fluency and verb fluency), and a qualitative analysis of the participants' word retrieval strategies was conducted.

RESULTS

No statistically significant group differences were found in the total number of retrieved words. When related to Swedish norm data, 43% of participants with cCMV infection, all asymptomatic at birth, had adequate results on both FAS and verb fluency tasks, compared to 86% of the controls. Education level was the most important factor for word fluency ability in both groups. Adults with cCMV infection and higher education levels used less effective retrieval strategies on FAS letter fluency than controls.

CONCLUSION

This study suggests that adults with cCMV infection may have deficits in the word retrieval process, even in the absence of known neurodevelopmental disorders. Long-term effects of cCMV infection may exist even in those with asymptomatic infection at birth.

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.

Beyond TORCH: A narrative review of the impact of antenatal and perinatal infections on the risk of disability

Infections and inflammation during pregnancy or early life can alter child neurodevelopment and increase the risk for structural brain abnormalities and mental health disorders. There is strong evidence that TORCH infections (i.e., Treponema pallidum, Toxoplasma gondii, rubella virus, cytomegalovirus, herpes virus) alter fetal neurodevelopment across multiple developmental domains and contribute to motor and cognitive disabilities. However, the impact of a broader range of viral and bacterial infections on fetal development and disability is less well understood. We performed a literature review of human studies to identify gaps in the link between maternal infections, inflammation, and several neurodevelopmental domains. We found strong and moderate evidence respectively for a higher risk of motor and cognitive delays and disabilities in offspring exposed to a range of non-TORCH pathogens during fetal life. In contrast, there is little evidence for an increased risk of language and sensory disabilities. While guidelines for TORCH infection prevention during pregnancy are common, further consideration for prevention of non-TORCH infections during pregnancy for fetal neuroprotection may be warranted.

Significance of cytomegalovirus tests after three weeks of life in children with hearing loss

BACKGROUND

To determine the diagnostic role of viral markers for cytomegalovirus (CMV) when tested after the diagnostically critical period (postnatal 3 weeks) in children with sensorineural hearing loss (SNHL).

METHODS

A retrospective review of 104 subjects who underwent CMV diagnostic tests after the critical period of 3 postnatal three weeks but before 24 months of age. Infants included had not passed universal newborn hearing screening tests in at least one ear and thus underwent obligatory follow up audiology testing as well as either exome sequencing or magnetic resonance imaging in cases of SNHL. Our cohort was classified into four subgroups depending on the results from audiological and etiologic diagnostic tests (genetic and radiological tests): congenital CMV (cCMV)-related SNHL (Group 1, n = 9), SNHL with another clear etiology (Group 2, n = 34), and SNHL classified as neither Group 1 nor 2 (Group 3, n = 18). We added age-matched, normal-hearing children (Group 4, n = 43) as a control group. CMV related viral metrics were compared among these four groups.

RESULTS

CMV PCR positivity, PCR titers, and culture positivity successfully differentiated Group 1 from Groups 2 and 4. Group 3 showed values of these parameters that were significantly different from Groups 2 and 4, while being more similar to those in Group 1, suggesting that a substantial portion of Group 3 truly had cCMV deafness. A hypothetical formula was developed to predict cCMV infections using logistic regression analysis.

CONCLUSION

This is the first study to propose the clinical significance of CMV test results obtained after 3 weeks post-birth in children with SNHL and to suggest how we can utilize them.

The association between congenital cytomegalovirus infection and cerebral palsy: A systematic review and meta-analysis

Cytomegalovirus (CMV) is the most common cause of congenital infection, affecting 1% of all live births. Intrauterine infection such as CMV infection is a risk factor for developing cerebral palsy. This study aims to investigate the association between congenital CMV infection and the development of cerebral palsy. A systematic literature search was conducted in PubMed, Web of Science and Ovid SP to identify relevant studies. The quality of studies was assessed using the Newcastle-Ottawa Scale. The random-effect model was used to calculate the pooled prevalence. The generic inverse variance method was used for statistical analysis. A total of 12 studies were included in this systematic review and meta-analysis. The overall pooled prevalence of cerebral palsy among patients diagnosed with congenital CMV infection was 26% (95% confidence interval (CI), 13-40%). The overall pooled prevalence of congenital CMV infection among patients with cerebral palsy was 10.9% (95% CI, 5-16%). Congenital CMV infection was significantly associated with the development of cerebral palsy in children. Routine follow-ups should be offered to screen for cerebral palsy.

Maternal Microbiome and Infections in Pregnancy

Pregnancy induces unique changes in maternal immune responses and metabolism. Drastic physiologic adaptations, in an intricately coordinated fashion, allow the maternal body to support the healthy growth of the fetus. The gut microbiome plays a central role in the regulation of the immune system, metabolism, and resistance to infections. Studies have reported changes in the maternal microbiome in the gut, vagina, and oral cavity during pregnancy; it remains unclear whether/how these changes might be related to maternal immune responses, metabolism, and susceptibility to infections during pregnancy. Our understanding of the concerted adaption of these different aspects of the human physiology to promote a successful pregnant remains limited. Here, we provide a comprehensive documentation and discussion of changes in the maternal microbiome in the gut, oral cavity, and vagina during pregnancy, metabolic changes and complications in the mother and newborn that may be, in part, driven by maternal gut dysbiosis, and, lastly, common infections in pregnancy. This review aims to shed light on how dysregulation of the maternal microbiome may underlie obstetrical metabolic complications and infections.

Multiple gene targeting siRNAs for down regulation of Immediate Early-2 (Ie2) and DNA polymerase genes mediated inhibition of novel rat Cytomegalovirus (strain All-03)

Background

Cytomegalovirus (CMV) is an opportunistic pathogen that causes severe complications in congenitally infected newborns and non-immunocompetent individuals. Developing an effective vaccine is a major public health priority and current drugs are fronting resistance and side effects on recipients. In the present study, with the aim of exploring new strategies to counteract CMV replication, several anti-CMV siRNAs targeting IE2 and DNA polymerase gene regions were characterized and used as in combinations for antiviral therapy.

Methods

The rat embryo fibroblast (REF) cells were transfected with multi siRNA before infecting with CMV strain ALL-03. Viral growth inhibition was measured by tissue culture infectious dose (TCID50), cytopathic effect (CPE) and droplet digital PCR (ddPCR) while IE2 and DNA polymerase gene knockdown was determined by real-time PCR. Ganciclovir was deployed as a control to benchmark the efficacy of antiviral activities of respective individual siRNAs.

Results

There was no significant cytotoxicity encountered for all the combinations of siRNAs on REF cells analyzed by MTT colorimetric assay (P > 0.05). Cytopathic effects (CPE) in cells infected by RCMV ALL-03 had developed significantly less and at much slower rate compared to control group. The expression of targeted genes was downregulated successfully resulted in significant reduction (P < 0.05) of viral mRNA and DNA copies (dpb + dpc: 79%, 68%; dpb + ie2b: 68%, 60%; dpb + dpc + ie2b: 48%, 42%). Flow cytometry analysis showed a greater percentage of viable and early apoptosis of combined siRNAs-treated cells compared to control group. Notably, the siRNAs targeting gene regions were sequenced and mutations were not encountered, thereby avoiding the formation of mutant with potential resistant viruses.

Conclusions

In conclusion. The study demonstrated a tremendous promise of innovative approach with the deployment of combined siRNAs targeting at several genes simultaneously with the aim to control CMV replication in host cells.

Implications of TORCH Diseases in Retinal Development-Special Focus on Congenital Toxoplasmosis

There are certain critical periods during pregnancy when the fetus is at high risk for exposure to teratogens. Some microorganisms, including Toxoplasma gondii, are known to exhibit teratogenic effects, interfering with fetal development and causing irreversible disturbances. T. gondii is an obligate intracellular parasite and the etiological agent of Toxoplasmosis, a zoonosis that affects one third of the world's population. Although congenital infection can cause severe fetal damage, the injury extension depends on the gestational period of infection, among other factors, like parasite genotype and host immunity. This parasite invades the Central Nervous System (CNS), forming tissue cysts, and can interfere with neurodevelopment, leading to frequent neurological abnormalities associated with T. gondii infection. Therefore, T. gondii is included in the TORCH complex of infectious diseases that may lead to neurological malformations (Toxoplasmosis, Others, Rubella, Cytomegalovirus, and Herpes). The retina is part of CNS, as it is derived from the diencephalon. Except for astrocytes and microglia, retinal cells originate from multipotent neural progenitors. After cell cycle exit, cells migrate to specific layers, undergo morphological and neurochemical differentiation, form synapses and establish their circuits. The retina is organized in nuclear layers intercalated by plexus, responsible for translating and preprocessing light stimuli and for sending this information to the brain visual nuclei for image perception. Ocular toxoplasmosis (OT) is a very debilitating condition and may present high severity in areas in which virulent strains are found. However, little is known about the effect of congenital infection on the biology of retinal progenitors/ immature cells and how this infection may affect the development of this tissue. In this context, this study reviews the effects that congenital infections may cause to the developing retina and the cellular and molecular aspects of these diseases, with special focus on congenital OT.

Hygiene promotion might be better than serological screening to deal with Cytomegalovirus infection during pregnancy: a methodological appraisal and decision analysis

BACKGROUND

Cytomegalovirus infection is the most frequent viral congenital infection, with possible consequences such as deafness, or psychomotor retardation. In 2016, the French High Council of Public Health was mandated to update recommendations regarding prevention of cytomegalovirus infection in pregnant women. We summarize a critical appraisal of knowledge and deterministic decision analysis comparing the current no-screening situation to serological screening during pregnancy, and to hygiene promotion.

METHODS

Screening was defined as systematic serological testing, during the first trimester, with repeated tests as needed, to all pregnant women. Outcomes were: 1) severe sequela: intellectual deficiency with IQ ≤ 50 or hearing impairment < 70 dB or sight impairment (≤ 3/10 at best eye); 2) moderate sequela: any level of intellectual, hearing or sight deficiency; and 3) death or termination of pregnancy. We simulated the one-year course of cytomegalovirus infection in a cohort of 800,000 pregnant women. We developed a deterministic decision model, using best and min-max estimates, extracted from systematic reviews or original studies.

RESULTS

Relevant data were scarce or imprecise. We estimated that 4352 maternal primary infections would result in 1741 foetal infections, and an unknown number of maternal reinfections would result in 1699 foetal infections. There would be 788 cytomegalovirus-related consequences, including 316 foetal deaths or terminations of pregnancy, and 424 moderate and 48 severe sequelae. Screening would result in a 1.66-fold increase of poor outcomes, mostly related to a 2.93-fold increase in deaths and terminations of pregnancy, not compensated by the decrease in severe symptomatic newborns. The promotion of hygiene would result in a 0.75-fold decrease of poor outcomes, related to both a decrease in severe sequelae among symptomatic newborns (RR = 0.75; min-max: 1.00-0.68), and in deaths and terminations of pregnancy (RR = 0.75; min-max: 0.97-0.68).

CONCLUSIONS

Prevention of cytomegalovirus infection during pregnancy should promote hygiene; serological screening should not be recommended.

Genetic and Epigenetic Etiology Underlying Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a pervasive neurodevelopmental disorder characterized by difficulties in social interaction, language development delays, repeated body movements, and markedly deteriorated activities and interests. Environmental factors, such as viral infection, parental age, and zinc deficiency, can be plausible contributors to ASD susceptibility. As ASD is highly heritable, genetic risk factors involved in neurodevelopment, neural communication, and social interaction provide important clues in explaining the etiology of ASD. Accumulated evidence also shows an important role of epigenetic factors, such as DNA methylation, histone modification, and noncoding RNA, in ASD etiology. In this review, we compiled the research published to date and described the genetic and epigenetic epidemiology together with environmental risk factors underlying the etiology of the different phenotypes of ASD.

[Neurological sequelae in patients with congenital cytomegalovirus]

INTRODUCTION

The infection due to cytomegalovirus is the most common congenital infection in developed countries, and on of the main causes of psychomotor impairment and neurosensory hearing loss of infectious origin. The present study has its objectives to describe the clinical-analytical and neuroimaging of patients with secondary neurological sequelae secondary to the congenital cytomegalovirus infection and then compare them with the group of patients with a congenital cytomegalovirus infection that did not have neurological symptoms during their follow-up.

MATERIAL AND METHODS

A retrospective, observational, cohort study was conducted that included all the cases of congenital cytomegalovirus infection from 2003 until 2018 and the short-medium term neurological sequelae were evaluated. Prenatal, perinatal, and postnatal data of patients with neurological sequelae were compared against those that did not present with any.

RESULTS

A total of 60 patients with congenital cytomegalovirus infection were recorded during the study period, with 65% having neurological involvement during their follow-up period (62.2% with psychomotor impairment, 61.5% with microcephaly, 46.2% loss of hearing, 27.8% motor disorders, 20.5% epilepsy, and 5.6% with chorioretinitis). In the patient group that had sequelae, the presence of clinical symptoms during the neonatal period, as well as changes in the neuroimaging study, were the most common, with both being statistically significant compared to the asymptomatic group. The patients with neurological involvement also had a higher score on the Noyola et al. neuroimaging scale.

CONCLUSIONS

The symptoms at birth, and certain findings in the neuroimaging, like the changes in the white matter or neuronal migration disorders, could predict neurocognitive sequelae in patients with congenital cytomegalovirus infection.

Executive Functions, Pragmatic Skills, and Mental Health in Children With Congenital Cytomegalovirus (CMV) Infection With Cochlear Implants: A Pilot Study

Congenital cytomegalovirus (cCMV) infection is the most common cause of progressive hearing impairment. In our previous study around 90% of children with a cCMV infection and CI had severely damaged balance functions (Karltorp et al., 2014). Around 20% had vision impairment, 15% were diagnosed with Autism-Spectrum-Disorder, and 20% with ADHD. One clinical observation was that children with cCMV infection had problems with executive functioning (EF), while controls with a genetic cause of deafness (Connexin 26 mutations; Cx26) did not have similar difficulties. A follow-up study was therefore initiated with the main objective to examine EF and pragmatic skills in relation to mental health in children with a cCMV infection and to draw a comparison with matched controls with Cx26 mutations (age, sex, hearing, non-verbal cognitive ability, vocabulary, and socioeconomic status level). Ten children with a cCMV infection and CI (4.8–12:9 years) and seven children with CI (4:8–12:8 years) participated in the study, which had a multidisciplinary approach. Executive functioning was assessed both with formal tests targeting working memory and attention, parent and teacher questionnaires, and a systematic observation by a blinded psychologist during one test situation. Pragmatics and mental health were investigated with parent and teacher reports. In addition, the early language outcome was considered in non-parametric correlation analyses examining the possible relationships between later EF skills, pragmatics, and mental health. Children with cCMV had a statistically significant worse pragmatic outcome and phonological working memory than controls despite their groups having similar non-verbal cognitive ability and vocabulary. However, there were no statistical differences between the groups regarding their EF skills in everyday settings and mental health. There were associations between early language outcomes and later EF skills and pragmatics in the whole sample.

Conclusion: Children with a cCMV infection are at risk of developing learning difficulties in school due to difficulties with phonological working memory and pragmatic skills in social interactions.

Congenital Cytomegalovirus Infection Masquerading as Antenatal Ventriculomegaly With Intraventricular Hemorrhage in a Term Neonate

Intraventricular hemorrhage is an uncommon manifestation of congenital cytomegalovirus (CMV) infection and has been described in preterm neonates. We discuss a term neonate, who was referred because of intracranial hemorrhage and hydrocephalous detected in the antenatal ultrasound. She had cholestatic jaundice, hepatitis, and thrombocytopenia, with positive polymerase chain reaction for CMV. Neuroimaging revealed reduced sulcation, mildly enlarged ventricles, and multiple periventricular cysts, along with residual hemorrhage in occipital horn of left lateral ventricle. She was started on ganciclovir, following which there was improvement in platelet count, jaundice, as well as transaminase levels.

Macular Colobomata: Comparison of Clinical and Optical Coherence Tomography Features With Serologic Results

PURPOSE

To assess the correlation between the morphologic features and serology in eyes with macular colobomata (MC).

DESIGN

Retrospective comparative case series.

METHODS

Setting: Institutional.

STUDY POPULATION

Patients presenting with MC to the retina clinic over a period of 2 years (January 2016 to December 2017). Interventional/Observational Procedure: Color fundus and swept-source optical coherence tomography (SSOCT) features were reviewed and assessed in 3 groups based on the serum IgG results: positive for Toxoplasma, positive for cytomegalovirus (CMV), and serology negative.

MAIN OUTCOME MEASURE

Morphologic features on clinical and OCT-based examination.

RESULTS

A total of 49 eyes of 27 patients were recruited. The mean age was 24.8 ± 14.9 years (range 7-60 years). While the lesion size, the presence of satellite lesions, choroidal excavation, and choroidal lacunae (large choroidal vessels) on SSOCT differed significantly among the groups, pigmentation, retinal fibrosis, shape, retinal vessel pattern, and choroidal vessel visibility did not vary significantly. The lesions in CMV serology-positive cases were mostly solitary (n = 8/8), large (n = 5/8) and deeply excavated (n = 8/8). The lesions in Toxoplasma serology-positive cases were mostly flat to shallow (n = 18/26), medium-sized (n = 19/26), and either a solitary lesion (n = 17/26) or multiple satellite lesions (n = 9/26). The lesions in serology-negative cases were mostly small to medium (n = 13/15), solitary (n = 15/15), deeply excavated lesions (n = 11/15) with choroidal lacunae (n = 8/15).

CONCLUSIONS

The clinical and SSOCT features such as the lesion size, the presence of satellite lesions, choroidal excavation, and choroidal lacunae can provide a clue toward the etiology of macular colobomata.

Clinical and Neuroimaging Spectrum of Peroxisomal Disorders

Peroxisomes play vital roles in a broad spectrum of cellular metabolic pathways. Defects in genes encoding peroxisomal proteins can result in a wide array of disorders, depending upon the metabolic pathways affected. These disorders can be broadly classified into 2 main groups; peroxisome biogenesis disorders (PBDs) and single peroxisomal enzyme deficiencies. Peroxisomal enzyme deficiencies are result of dysfunction of a specific metabolic pathway, while PBDs are due to generalized peroxisomal dysfunction. Mutations in PEX1 gene are the most common cause of PBDs, accounting for two-thirds of cases. Peroxisomal fission defects is a recently recognized entity, included under the subgroup of PBDs. The aim of this article is to provide a comprehensive review on the clinical and neuroimaging spectrum of peroxisomal disorders.

Pilot Study of Model-Based Dosage Individualization of Ganciclovir in Neonates and Young Infants with Congenital Cytomegalovirus Infection

Newborns with congenital cytomegalovirus (CMV) infection are at high risk for developing permanent sequelae. Intravenous ganciclovir therapy is frequently used for the treatment of congenital CMV infection. A target area under the concentration-time curve from 0 to 24 h (AUC_0-24) of 40 to 50 μg · h/ml is recommended. The standard dose has resulted in a large variability in ganciclovir exposure in newborns, indicating the unmet need of dosage individualization for this vulnerable population, but the implementation of this strategy remains challenging in clinical practice. We aim to evaluate the clinical utility of model-based dosage individualization of ganciclovir in newborns using an opportunistic sampling approach. The predictive performance of a published ganciclovir population pharmacokinetic model was evaluated using an independent patient cohort. The individual dose was adjusted based on the target AUC_0-24 to ensure its efficacy. A total of 26 newborns with congenital CMV infection were included in the present study. Only 11 (42.3%) patients achieved the target AUC_0-24 after being given the standard dose. For all the subtherapeutic patients (achieving <80% of the target AUC) (n = 5), a model-based dosage adjustment was performed using the Bayesian estimation method combined with the opportunistic sampling strategy. The adjusted doses were increased by 28.6% to 60.0% in these five patients, and all adapted AUC_0-24 values achieved the target (range, 48.6 to 66.1 μg · h/ml). The clinical utility of model-based dosing individualization of ganciclovir was demonstrated in newborns with congenital CMV infection. The population pharmacokinetic model combined with the opportunistic sampling strategy provides a clinically feasible method to adapt the ganciclovir dose in neonatal clinical practice. (This study has been registered at ClinicalTrials.gov under registration no. NCT03113344.).

Long-term stability of CMV DNA in human breast milk

BACKGROUND

Human cytomegalovirus (CMV) is the leading cause of intrauterine and perinatal viral infection. The most common route of CMV transmission in newborns is through breastmilk and this can lead to infant morbidity and mortality. Breast milk that has been frozen for an extended period may need to be tested for CMV DNA to determine the source of infection. It has been a challenge for clinical laboratories to ensure the stability of CMV DNA in frozen breast milk for accurate viral load measurement.

OBJECTIVES

To evaluate the stability of CMV DNA in breast milk by testing quantitative viral loads over a 28-day period for breast milk stored at 4 °C and a 90-day period for breast milk stored at -20 °C.

STUDY DESIGN

Baseline viral loads were determined on day 0 and the samples stored at 4 °C underwent extraction and amplification at four time points, up to 28 days. The samples stored at -20 °C underwent extraction and amplification at five time points up to 90 days. Log₁₀ values were calculated and t-test, Pearson's coefficient, and concordance correlation coefficient were calculated.

RESULTS

There was no statistically significant difference between the time points by t-test, and correlation coefficients showed greater than 90% concordance for days 0 and 28 as well as days 0 and 90 at both storage temperatures tested.

CONCLUSIONS

The concentration of CMV DNA in breast milk was stable for 28 days at 4 °C and 90 days at -20 °C as the concentrations did not differ significantly from the baseline viral loads.

Cytomegalovirus DNA Detection by Polymerase Chain Reaction in Cerebrospinal Fluid of Infants With Congenital Infection: Associations With Clinical Evaluation at Birth and Implications for Follow-up

Background

DNA detection of human cytomegalovirus (hCMV) in cerebrospinal fluid (CSF) by polymerase chain reaction (PCR) is a marker of central nervous system (CNS) involvement in congenital hCMV infection (cCMV), but its prognostic value is unknown.

Methods

A multicenter, retrospective study was performed using the Spanish Congenital Cytomegalovirus Infection Database (REDICCMV; http://www.cmvcongenito.es). Newborns with cCMV and a lumbar puncture performed were included and classified according to their hCMV-PCR in CSF result (positive/negative). Clinical characteristics, neuroimaging abnormalities, plasma viral load, and audiological and neurological outcomes of both groups were compared.

Results

A total of 136 neonates were included in the study: 21 (15.4%) with positive CSF hCMV-PCR and 115 (84.6%) with negative results. Seventeen patients (81%) in the positive group were symptomatic at birth compared with 52.2% of infants in the negative group (odds ratio [OR], 3.86; 95% confidence interval [CI], 1.28-14.1; P = .01). Only 4 asymptomatic newborns (6.8%) had a positive CSF hCMV-PCR. There were no differences between groups regarding the rate of microcephaly, neuroimaging abnormalities, neurological sequelae at 6 months of age, or plasma viral load. Sensorineural hearing loss (SNHL) at birth was associated with a positive CSF hCMV-PCR result (OR, 3.49; 95% CI, 1.08-11.27; P = .04), although no association was found at 6 months of age.

Conclusions

A positive hCMV-PCR result in CSF is associated with symptomatic cCMV and SNHL at birth. However, no differences in neuroimaging studies, plasma viral load, or outcomes at 6 months were found. These results suggest that hCMV-PCR in CSF may not be a useful prognostic marker in cCMV.

Cyclophilin A as a target in the treatment of cytomegalovirus infections

BACKGROUND

Viruses are obligate parasites that depend on the cellular machinery of the host to regenerate and manufacture their proteins. Most antiviral drugs on the market today target viral proteins. However, the more recent strategies involve targeting the host cell proteins or pathways that mediate viral replication. This new approach would be effective for most viruses while minimizing drug resistance and toxicity.

METHODS

Cytomegalovirus replication, latency, and immune response are mediated by the intermediate early protein 2, the main protein that determines the effectiveness of drugs in cytomegalovirus inhibition. This review explains how intermediate early protein 2 can modify the action of cyclosporin A, an immunosuppressive, and antiviral drug. It also links all the pathways mediated by cyclosporin A, cytomegalovirus replication, and its encoded proteins.

RESULTS

Intermediate early protein 2 can influence the cellular cyclophilin A pathway, affecting cyclosporin A as a mediator of viral replication or anti-cytomegalovirus drug.

CONCLUSION

Cyclosporin A has a dual function in cytomegalovirus pathogenesis. It has the immunosuppressive effect that establishes virus replication through the inhibition of T-cell function. It also has an anti-cytomegalovirus effect mediated by intermediate early protein 2. Both of these functions involve cyclophilin A pathway.

Pneumonia

Neonatal pneumonia may occur in isolation or as one component of a larger infectious process. Bacteria, viruses, fungi, and parasites are all potential causes of neonatal pneumonia, and may be transmitted vertically from the mother or acquired from the postnatal environment. The patient's age at the time of disease onset may help narrow the differential diagnosis, as different pathogens are associated with congenital, early-onset, and late-onset pneumonia. Supportive care and rationally selected antimicrobial therapy are the mainstays of treatment for neonatal pneumonia. The challenges involved in microbiological testing of the lower airways may prevent definitive identification of a causative organism. In this case, secondary data must guide selection of empiric therapy, and the response to treatment must be closely monitored.

Human cytomegalovirus reactivation from latency: validation of a "switch" model in vitro

Background

Human cytomegalovirus (HCMV) is an opportunistic pathogen leading to severe and even fatal diseases in ‘at-risk’ categories of individuals upon primary infection or the symptomatic reactivation of the endogenous virus. The mechanisms which make the virus able to reactivate from latency are still matter of intense study. However, the very low number of peripheral blood monocytes (an important latent virus reservoir) harbouring HCMV DNA makes it very difficult to obtain adequate viral quantities to use in such studies.

Thus, the aim of the present study was to demonstrate the usefulness of human THP-1 monocytes, mostly employed as HCMV latent or lytic infection system, as a reactivation model.

Methods

THP-1 monocytes were infected with HCMV TB40E strain (latency model) at multiplicities of infection (MOI) of 0.5, 0.25 or 0.125. After infection, THP-1 aliquots were differentiated into macrophages (reactivation model). Infections were carried out for 30 h, 4, 6 and 7 days. Viral DNA evaluation was performed with viable and UV-inactivated virus by q-Real-Time PCR. RNA extracted from latency and reactivation models at 7 days post-infection (p.i.) was subjected to RT-PCR to analyse viral latency and lytic transcripts. To perform viral progeny analysis and titration, the culture medium from infected THP-1 latency and reactivation models (7 days p.i.) was used to infect human fibroblasts; it was also checked for the presence of exosomes.

For viral progeny analysis experiments, the Towne strain was also used.

Results

Our results showed that, while comparable TB40E DNA amounts were present in both latent and reactivation models at 30 h p.i., gradually increased quantities of viral DNA were only evident in the latter model at 4, 6, 7 days p.i.. The completion of the lytic cycle upon reactivation was also proved by the presence of HCMV lytic transcripts and an infectious viral yield at 7 days p.i.

Conclusions

Our data demonstrate the effectiveness of THP-1 cells as a “switch” model for studying the mechanisms that regulate HCMV reactivation from latency. This system is able to provide adequate quantities of cells harbouring latent/reactivated virus, thereby overcoming the intrinsic difficulties connected to the ex vivo system.

Electronic supplementary material

The online version of this article (doi:10.1186/s12985-016-0634-z) contains supplementary material, which is available to authorized users.

Diffuse periventricular calcification and brain atrophy: A case of neonatal central nervous system cytomegalovirus infection

TORCH refers to the most common congenitally acquired infections: toxoplasma, rubella, cytomegalovirus, and herpes simplex virus. Neonatal cytomegalovirus infection remains a common cause of congenital infection worldwide with effects ranging from hearing impairment to significant neurological morbidity. We report a case of a term neonate with ventriculomegaly on prenatal ultrasound who presented with low birth weight, small head circumference, hepatosplenomegaly, and purpuric rash on physical exam. Central nervous system cytomegalovirus infection typically shows periventricular calcifications and associated deep white matter damage and ventriculomegaly. Ultrasound, computed tomography, and magnetic resonance imaging have different roles in the diagnosis of congenital central nervous system cytomegalovirus infection. Many imaging features of congenital cytomegalovirus are distinctive, and can spur a diagnostic work-up as well as help provide a prognosis.

Vertically transmitted cytomegalovirus infection in newborn preterm infants

OBJECTIVE

To determine the epidemiology of congenital and acquired cytomegalovirus (CMV) infections in preterm infants and to analyze the efficacy of breast milk freezing in decreasing the vertical transmission rate of CMV.

STUDY DESIGN

During 2013 and 2014, preterm newborns who weighed ≤1500 g and were admitted to 22 Spanish neonatal units were included and screened for CMV infection according to the Spanish Neonatology Society recommendations. Each hospital treated the breast milk according to its own protocols.

RESULTS

Among the 1236 preterm neonates included, 10 had a congenital infection (0.8%) and 49 had an acquired infection (4.0%) (82% demonstrated positive PCR-CMV in breast milk). The neonates who received only frozen milk presented less frequently with acquired infection (1.2%) than those fed fresh milk (5.5%) (RR=0.22; 95% CI 0.05-0.90; P=0.017). The newborns who received bank milk followed by frozen or fresh breast milk more frequently had an acquired infection (2.1% or 2.2%, respectively) than those fed only frozen breast milk.

CONCLUSIONS

The incidence of congenital CMV infection in our sample is low, as described in the literature. To reduce acquired CMV infection, freezing breast milk might be an advisable procedure for preterm neonates born from seropositive mothers, either from the beginning of lactation or after a period of bank milk administration.

A dynamic transmission model with age-dependent infectiousness and reactivation for cytomegalovirus in the United States: Potential impact of vaccination strategies on congenital infection

We present an age-structured dynamic transmission model for cytomegalovirus (CMV) in the United States, based on natural history and available data, primarily aiming to combine the available qualitative and quantitative knowledge toward more complex modeling frameworks to better reflect the underlying biology and epidemiology of the CMV infection. The model structure explicitly accounts for primary infections, reactivations and re-infections. Duration of infectiousness and likelihood of reactivation were both assumed to be age-dependent, and natural reduction in the re-infection risk following primary infection was included. We used an empirical social contact matrix (POLYMOD-based) as support for CMV transmission between different age groups. The baseline model reproduced well the age-stratified seroprevalence data (National Health and Nutrition Examination Survey III) used for calibration. The model was further used to explore the potential impact of hypothetical vaccination on reducing congenital CMV infection under various vaccine profiles and vaccination scenarios. Our preliminary model-based simulations suggested that while infant vaccination may represent an attractive way to reduce congenital CMV infection over time, adolescent female vaccination with an adequate routine booster platform may, under certain conditions, provide an alternative. However, for such tools to be considered toward actual decision-making, enhanced validations based on additional studies and data would be further necessary. The modeling framework presented in this paper was designed to be sufficiently general and flexible, such that it can allow for further adaptations to reflect new knowledge or data that may become available in the future.

Clinical Significance of IgG Avidity Testing and Other Considerations in the Diagnosis of Congenital Cytomegalovirus Infection: A Review Update

Prompt and accurate laboratory testing of women before or during antenatal days is necessary for detecting humoral immunological responses against cytomegalovirus (CMV) infection and assessing risk of congenital transmission. CMV is the most common viral etiology with the greatest propensity to induce neonatal pathologies. Most healthcare facilities in developing countries rely solely on anti-CMV IgM and IgG assays in diagnosing CMV infections. However, these parameters have some worrisome limitations. This study reviewed the significance of IgG avidity testing as a highly sensitive and specific tool that improves decisions regarding diagnosis of maternal and congenital CMV infections. We conducted this review from relevant published articles using an extensive literature search made through PubMed, Scopus and Google scholar on the concepts of congenital CMV (CCMV) transmission and clinical significance of IgG avidity testing in diagnosis of CCMV infections. Findings from our review revealed that IgG avidity testing in some developed societies was frequently utilized to resolve dilemmas associated with serodiagnosis of CMV infections, however, there is paucity of information in regards to its use in developing countries. The non-inclusion of IgG avidity testing during serological investigations of CMV could be a reason why congenital CMV infections and associated pathologies often go underdiagnosed in developing countries.

Comparison of Presentation, Course, and Outcome of Congenital and Acquired Cytomegalovirus Infection in Twins

Background Cytomegalovirus (CMV) is one of the most common causes of serious viral intrauterine infections. It is universally distributed among the human population with an average incidence of 0.15 to 2%. Indeed, at least half of the women in the reproductive age have evidence of prior CMV infection. Epidemiology and Pathogenicity However, it is not a usual practice to screen asymptomatic pregnant woman or neonates for CMV. Even if a mother developed a primary CMV infection during pregnancy, up to 90% of the newborns with congenital CMV will be asymptomatic at the time of birth. Only 5 to 7% of the infected babies will be acutely symptomatic, and the typical clinical presentation includes intrauterine growth restriction, microcephaly, various cutaneous manifestations (including petechiae and purpura), hematological abnormalities (particularly resistant thrombocytopenia), hepatosplenomegaly, chorioretinitis, hepatitis, etc. In contrast, acquired CMV infection is extremely unlikely to cause any serious sequelae for the infant. Cases  We present a case of congenital and acquired CMV infection in twins with a focus of dissimilarity in presentation, clinical course, and outcome.

Lenticulostriate Vasculopathy in Brain Ultrasonography is Associated with Cytomegalovirus Infection in Newborns

BACKGROUND

Lenticulostriate vasculopathy is associated with various disorders, in particular cytomegalovirus infection, which can cause neurological consequences. We wanted to evaluate the association of lenticulostriate vasculopathy and cytomegalovirus infection. We retrospectively collected data on lenticulostriate vasculopathy from 858 neonatal ultrasonography scans.

METHODS

Fifty-five patients with lenticulostriate vasculopathy were diagnosed. Lenticulostriate vasculopathy was classified as severe and mild according to the ultrasonographic findings. We analyzed gender, unilateral and bilateral lenticulostriate vasculopathy, mild and severe lenticulostriate vasculopathy, intrauterine growth retardation, and lenticulostriate vasculopathy associated with other brain malformations to determine whether they were correlated with cytomegalovirus infection.

RESULTS

Neonatal cytomegalovirus infections correlated primarily with lenticulostriate vasculopathy that was associated with brain structure anomalies p < 0.0001, followed by severe lenticulostriate vasculopathy (p = 0.029). Cytomegalovirus urine polymerase chain reaction ratios were 69% for severe and 23% for mild lenticulostriate vasculopathy (p = 0.002; odds ratio = 7.33). Of 72 newborns with intrauterine growth retardation without lenticulostriate vasculopathy, 33 were analyzed for cytomegalovirus, of whom only one was positive, which was significantly different from the newborns with lenticulostriate vasculopathy (p = 0.003; odds ratio = 11.64).

CONCLUSION

Lenticulostriate vasculopathy on neonatal ultrasonography is useful for predicting cytomegalovirus infection, particularly in severe lenticulostriate vasculopathy. When severe lenticulostriate vasculopathy is associated with a brain structure anomaly, cytomegalovirus infection should be considered. The outcomes for the cases in which cytomegalovirus infection was associated with other brain structure anomalies were significantly worse than the outcomes in cases associated with lenticulostriate vasculopathy only.

Fetal cytomegalovirus infection manifesting as transient pancytopenia

We encountered a patient with a fetal cytomegalovirus infection manifesting as pancytopenia and thoracic hypoplasia. The fetal anemia was treated by transfusion via the umbilical cord, and did not progress after 22 weeks' gestation. The neutropenia resolved spontaneously, and only thrombocytopenia was persistent at birth. The severe thoracic hypoplasia led to pulmonary hypertension and required intensive postnatal respiratory management. Our experience suggests that pancytopenia is a possible manifestation in fetuses infected with cytomegalovirus. This may be transient, resolving spontaneously during fetal life; however, caution should be taken with blood counts, particularly platelet counts, after delivery. In addition, clinicians should carefully follow the thoracic volume in cytomegalovirus-infected fetuses and consider the possibility of postnatal severe respiratory insufficiency.

Magnetic resonance imaging in viral and prion diseases of the central nervous system

The early detection and specific diagnosis of viral infections of the central nervous system are important because many of these diseases are potentially treatable. However, clinical symptoms and physical examination are often nonspecific, and rapid diagnostic tests are available for some, but not all, viruses. Neuroimaging, in conjunction with clinical history and laboratory tests, plays an important role in narrowing the differential diagnoses. In this article, we review the clinical features, imaging characteristics, diagnosis, and treatment of the more common viral infections and prions that involve the central nervous system.

Discordant humoral and cellular immune responses to Cytomegalovirus (CMV) in glioblastoma patients whose tumors are positive for CMV

Background. Glioblastoma (GBM) is the most common malignant brain tumor in adults and is nearly always fatal. Emerging evidence suggests that human Cytomegalovirus (HCMV) is present in 90-100% of GBMs and that add-on antiviral treatment for HCMV show promise to improve survival. Methods. In a randomized, placebo-controlled trial of valganciclovir in 42 GBM patients, blood samples were collected for analyses of HCMV DNA, RNA, reactivity against HCMV peptides, IgG, and IgM at baseline and at 3, 12, and 24 weeks of treatment. Results. All 42 tumors were positive for HCMV protein. All patients examined had at least one blood sample positive for HCMV DNA, 63% were HCMV RNA positive, and 21% were IgM positive. However, 29% of GBM patients were IgG negative for HCMV. Five of these samples were positive in an enzyme-linked immunosorbent assay (ELISA) that used antigens derived from a clinical isolate. Blood T cells from 11 of 13 (85%) HCMV IgG-negative GBM patients reacted against HCMV peptides. Valganciclovir did not affect IgG titers, DNA, or RNA levels of the HCMV immediate early (HCMV IE) gene in blood. Conclusion. In GBM patients, HCMV activity is higher than in healthy controls and serology is a poor test to define previous or active HCMV infection in these patients.

Neuro-imaging findings in infants with congenital cytomegalovirus infection: relation to trimester of infection

BACKGROUND

Congenital cytomegalovirus (cCMV) infection early in pregnancy may result in major disabilities. Cerebral abnormalities detected using cranial ultrasound (cUS) and magnetic resonance imaging (MRI) have been related to neurological sequelae.

OBJECTIVE

To evaluate the additional value of MRI and assess the relationship between time of infection during pregnancy and outcome in infants with cCMV infection.

METHODS AND STUDY DESIGN

Demographic and clinical data were collected in infants with cCMV infection (1992-2013). Trimester of infection, neuro-imaging results and outcome were reviewed. Cerebral abnormalities were categorized into none, mild (lenticulostriate vasculopathy, germinolytic cysts, high signal intensity on T2-weighted images) and severe (migrational disorder, ventriculomegaly, cerebellar hypoplasia). Results were statistically analysed.

RESULTS

Thirty-six infants were eligible for analysis. cUS was performed in all and cranial MRI in 20 infants. Migrational disorders were only diagnosed using MRI (p < 0.01). In 17 infants trimester of infection was ascertained. Seven out of 10 infants infected during the first trimester had severe abnormalities on cUS (5 confirmed on MRI) and adverse sequelae; 3 had no/mild abnormalities on cUS/MRI and normal outcome. Two out of 3 infants infected during the second trimester with no/mild abnormalities on cUS/MRI had normal outcome; 1 with mild cUS and MRI abnormalities developed sensorineural hearing loss. Four infants infected during the third trimester with no/mild abnormalities on cUS/MRI had normal outcome.

CONCLUSION

Infants with a first trimester cCMV infection are most at risk of severe cerebral abnormalities and neurological sequelae. MRI, and not cUS, enables an early diagnosis of migrational disorders, which can improve prediction of outcome.

Double encephalitis with herpes simplex virus type II and cytomegalovirus in an elder Chinese: a case report

Herpes simplex encephalitis is a rare disease. In adults, most of the reported cytomegalovirus (CMV) infections are seen in immunocompromised patients. We present a case of 67-year-old Chinese male with the coinfection of CMV and herpes simplex virus type II (HSV-II). He had no history of being treated with immunosuppressants, showed symptoms of psychosis and was scored 109 on the Positive and Negative Syndrome Scale. This patient presented with a rare case of coinfection of CMV and herpes simplex virus type II with psychotic symptoms.

A perinatal cytomegalovirus infection in an immunocompetent patient with chorioretinitis

Cytomegalovirus (CMV) infection is the most common viral infection of newborns in all periods worldwide. Perinatal form of infection is usually less severe than the congenital form because of having a lower rate for serious organ involvement like central nervous system. In this article, we report a 3-month-old immunocompetent patient who was diagnosed as having perinatal CMV infection with a scar of chorioretinitis after presenting with gastroenteritis and hepatitis.

CMV infection associated with severe lung involvement and persistent pulmonary hypertension of the newborn (PPHN) in two preterm twin neonates

The diagnosis of congenital CMV is usually guided by a number of specific symptoms and findings. Unusual presentations may occur and diagnosis is challenging due to uncommon or rare features. Here we report the case of two preterm, extremely low birthweight, 28-week gestational age old twin neonates with CMV infection associated with severe lung involvement and persistent pulmonary hypertension of the newborn (PPHN). They were born to a HIV-positive mother, hence they underwent treatment with zidovudine since birth. Both infants featured severe refractory hypoxemia, requiring high-frequency ventilation, inhaled nitric oxide and inotropic support, with full recovery after 2 months. Treatment with ganciclovir was not feasible due the concomitant treatment with zidovudine and the risk of severe, fatal toxicity. Therefore administration of intravenous hyperimmune anti-CMV immunoglobulin therapy was initiated. Severe lung involvement at birth and subsequent pulmonary hypertension are rarely described in preterm infants as early manifestations of CMV congenital disease. In the two twin siblings here described, the extreme prematurity and the treatment with zidovudine likely worsened immunosuppression and ultimately required a complex management of the CMV-associated lung involvement.

Human cytomegalovirus infection of human embryonic stem cell-derived primitive neural stem cells is restricted at several steps but leads to the persistence of viral DNA

Congenital human cytomegalovirus (HCMV) infection is a major cause of central nervous system structural anomalies and sensory impairments. It is likely that the stage of fetal development, as well as the state of differentiation of susceptible cells at the time of infection, affects the severity of the disease. We used human embryonic stem (ES) cell-derived primitive prerosette neural stem cells (pNSCs) and neural progenitor cells (NPCs) maintained in chemically defined conditions to study HCMV replication in cells at the early stages of neural development. In contrast to what was observed previously using fetus-derived NPCs, infection of ES cell-derived pNSCs with HCMV was nonprogressive. At a low multiplicity of infection, we observed only a small percentage of cells expressing immediate-early genes (IE) and early genes. IE expression was found to be restricted to cells negative for the anterior marker FORSE-1, and treatment of pNSCs with retinoic acid restored IE expression. Differentiation of pNSCs into NPCs restored IE expression but not the transactivation of early genes. Virions produced in NPCs and pNSCs were exclusively cell associated and were mostly non-neural tropic. Finally, we found that viral genomes could persist in pNSC cultures for up to a month after infection despite the absence of detectable IE expression by immunofluorescence, and infectious virus could be produced upon differentiation of pNSCs to neurons. In conclusion, our results highlight the complex array of hurdles that HCMV must overcome in order to infect primitive neural stem cells and suggest that these cells might act as a reservoir for the virus.

IMPORTANCE

Human cytomegalovirus (HCMV) is a betaherpesvirus that is highly prevalent in the population. HCMV infection is usually asymptomatic but can lead to severe consequences in immunosuppressed individuals. HCMV is also the most important infectious cause of congenital developmental birth defects. Manifestations of fetal HCMV disease range from deafness and learning disabilities to more severe symptoms such as microcephaly. In this study, we have used embryonic stem cells to generate primitive neural stem cells and have used these to model HCMV infection of the fetal central nervous system (CNS) in vitro. Our results reveal that these cells, which are similar to those present in the developing neural tube, do not support viral replication but instead likely constitute a viral reservoir. Future work will define the effect of viral persistence on cellular functions as well as the exogenous signals leading to the reactivation of viral replication in the CNS.

How to use... neonatal TORCH testing

Toxoplasma gondii, rubella, cytomegalovirus and herpes simplex virus have in common that they can cause congenital (TORCH) infection, leading to fetal and neonatal morbidity and mortality. During the last decades, TORCH screening, which is generally considered to be single serum testing, has been increasingly used inappropriately and questions have been raised concerning the indications and cost-effectiveness of TORCH testing. The problems of TORCH screening lie in requesting the screening for the wrong indications, wrong interpretation of the single serum results and in case there is a good indication for diagnosis of congenital infection, sending in the wrong materials. This review provides an overview of the pathogenesis, epidemiology and clinical consequences of congenital TORCH infections and discusses the indications for, and interpretation of, TORCH screens.

Intraventricular hemorrhage and multiple intracranial cysts associated with congenital cytomegalovirus infection

Intraventricular hemorrhage with congenital cytomegalovirus (CMV) infection is rare and has been reported only in extremely premature infants or in association with thrombocytopenia. We report the first case of a full-term male infant with congenital CMV infection and intraventricular hemorrhage with a normal platelet count and coagulation profile. The infant also had a left subependymal cyst and bilateral occipital cysts without any other manifestations of CMV infection.

Viral mitochondria-localized inhibitor of apoptosis (UL37 exon 1 protein) does not protect human neural precursor cells from human cytomegalovirus-induced cell death

Congenital human cytomegalovirus (HCMV) infection can cause severe brain abnormalities. Apoptotic HCMV-infected brain cells have been detected in a congenitally infected infant. In biologically relevant human neural precursor cells (hNPCs), cultured in physiological oxygen tensions, HCMV infection (m.o.i. of 1 or 3) induced cell death within 3 days post-infection (p.i.) and increased thereafter. Surprisingly, its known anti-apoptotic genes, including the potent UL37 exon 1 protein (pUL37x1) or viral mitochondria-localized inhibitor of apoptosis (vMIA), which protects infected human fibroblasts (HFFs) from apoptosis and from caspase-independent, mitochondrial serine protease-mediated cell death, were expressed by 2 days p.i. Consistent with this finding, an HCMV UL37x1 mutant, BADsubstitutionUL37x1 (BADsubUL37x1) induced cell death in hNPCs (m.o.i. = 1) to level which were indistinguishable from parental virus (BADwild-type)-infected hNPCs. Surprisingly, although BADsubUL37x1 is growth defective in permissive HFFs, it produced infectious progeny in hNPCs with similar kinetics and to levels comparable to BADwild-type-infected hNPCs (m.o.i. = 1). While delayed at a lower multiplicity (m.o.i. = 0.3), the BADsubUL37x1 mutant reached similar levels to revertant within 12 days, in contrast to its phenotype in HFFs. The inability of pUL37x1/vMIA to protect hNPCs from HCMV-induced cell death did not result from impaired trafficking as pUL37x1/vMIA trafficked efficiently to mitochondria in transfected hNPCs and in HCMV-infected hNPCs. These results establish that pUL37x1/vMIA, although protective in permissive HFFs, does not protect HCMV-infected hNPCs from cell death under physiologically relevant oxygen tensions. They further suggest that pUL37x1/vMIA is not essential for HCMV growth in hNPCs and has different cell type-specific roles.

Infectious agents associated with schizophrenia: a meta-analysis

Schizophrenia is a highly disabling and limiting disorder for patients and the possibility that infections by some microorganisms may be associated to its development may allow prevention and recovery. In the current study we have done a meta-analysis of studies that have assessed the possible association between detection of different infectious agents and schizophrenia. We report results that support the idea that there is a statistically significant association between schizophrenia and infection by Human Herpesvirus 2 (OR=1.34; CI 95%: 1.09-1.70; p=0.05), Borna Disease Virus (OR=2.03; CI 95%: 1.35-3.06; p<0.01), Human Endogenous Retrovirus W (OR=19.31; CI 95%: 6.74-55.29; p<0.001), Chlamydophila pneumoniae (OR=6.34; CI 95%: 2.83-14.19; p<0.001), Chlamydophila psittaci (OR=29.05; CI 95%: 8.91-94.70; p<0.001) and Toxoplasma gondii (OR=2.70; CI 95%: 1.34-4.42; p=0.005). The implications of these findings are discussed and further research options are also explicated.