Congenital cytomegalovirus infection: epidemiology, prediction, diagnosis, and emerging treatment options for symptomatic infants

Late-onset and congenital hearing loss detected using AABR due to congenital cytomegalovirus infection that improved with valganciclovir

Congenital cytomegalovirus (cCMV) infection is the most common congenital viral infection and is the leading non-genetic cause of sensorineural hearing loss and an important cause of neurodevelopmental disabilities. Auto auditory brainstem response (AABR) is a simple hearing test and used for the purpose of neonatal hearing screening, but can use it for early detection hard of hearing within the study age of the model. We experienced two case of asymptomatic CMV infection in which congenital and late-onset hearing loss were diagnosed early with AABR, and hearing loss improved with valganciclovir.

Cytomegalovirus infection in a single-centre Australian neonatal cohort

AIM

Congenital cytomegalovirus (cCMV) is the most common infectious cause of congenital malformation, non-genetic sensorineural hearing loss and neurodevelopmental sequelae in childhood. The primary aim of this retrospective cohort study was to identify the birth and neurodevelopmental outcomes of neonates diagnosed with symptomatic and asymptomatic cCMV in a large regional tertiary referral hospital.

METHODS

This was a retrospective cohort study of laboratory-based cCMV diagnoses in neonates born at a single study centre between January 2005 and January 2020. Audit of medical records was undertaken to evaluate maternal characteristics, symptom patterns, radiological and neurodevelopmental outcomes of neonates meeting the laboratory diagnostic criteria during the first 24 months.

RESULTS

There were 45 neonates with proven CMV infection and 27 mothers with proven infection with an associated pregnancy outcome. Nineteen neonates were born at term (>37 weeks). Of these, 32 (71.1%) neonates had a significant intercurrent comorbidity and 22 (48.9%) neonates were reported to have a degree of delay in one or more developmental domains. A large proportion (77.3%) of the symptomatic untreated neonates had an unknown history of maternal infection compared to the asymptomatic (10.0%) and symptomatic treated (53.8%) neonates (P = 0.001).

CONCLUSION

Up to half of the neonates with cCMV were at risk of developing a degree of developmental delay at our centre. Whether these outcomes are related primarily to CMV infection or are confounded by the co-existence of prematurity is unclear and needs further evaluation in prospective studies.

Oral Valganciclovir Therapy in Infants Aged ≤2 Months with Congenital Cytomegalovirus Disease: A Multicenter, Single-Arm, Open-Label Clinical Trial in Japan

Our aims were to determine the clinical impact of oral valganciclovir (VGCV) in infants aged ≤2 months with congenital cytomegalovirus (CMV) disease and evaluate the efficacy of VGCV when initiated beyond the neonatal period. The multicenter, single-arm, open-label clinical trial was conducted in Japan. Twenty-five infants aged ≤2 months with congenital CMV disease involving the central nervous system were enrolled and treated with VGCV for 6 months. The primary endpoint was the change in the whole blood CMV load before and after treatment. The secondary endpoint was the change in the auditory brainstem response (ABR) before and after treatment. Changes in ABR were assessed between the younger and older age groups (≤ and >30 days at treatment initiation). Of the 25 patients, one was excluded owing to epilepsy before VGCV administration. The median change in the CMV DNA level in whole blood was −246.0 IU/mL. The best ear and total ear assessments based on ABR were categorized as (improved + unchanged) after treatment for 100% and 93.8%, respectively. No differences in hearing efficacy were observed between the younger and older age groups. Oral VGCV is a potential therapeutic option for treating infants aged ≤2 months with congenital CMV disease.

Survey of physician knowledge of congenital cytomegalovirus infection and clinical practices in Japan: A web-based survey

Congenital cytomegalovirus infection (cCMVi) can cause serious and long-term effects in newborns. Without available vaccines or antiviral prophylaxis, prevention strategies for cCMVi and cytomegalovirus disease during pregnancy are limited to hygiene and behavioral interventions to prevent transmission. The objective of this study was to assess cCMVi-related awareness, knowledge, and physicians' actual and preferred clinical practices in Japan. This web-based cross-sectional survey was conducted using online panels. Survey invitations were sent by email to physicians (pediatricians, obstetricians, otolaryngologists, and internists). Participants were asked about their awareness of congenital conditions, including cCMVi. Participants who were aware of cCMVi were then asked additional questions related to the study objectives. Participants included 292 pediatricians, 245 obstetricians, 245 otolaryngologists, and 279 internists. Awareness of cCMVi was generally high (69.2%-97.6%). Pediatricians and obstetricians were most knowledgeable about cCMVi; however, responses to specific questions such as those pertaining to risk factors, patient counseling, and clinical management of cCMVi varied. For example, correct identification of potential cytomegalovirus transmission routes among pediatricians ranged from 36.8% to 65.6%. Survey results showed a discrepancy between responses when physicians were asked about their actual and preferred clinical practices to manage cCMVi. For example, although around 90% of obstetricians and pediatricians considered it preferred practice to educate pregnant women about cCMVi, only 60.1% of obstetricians reported being able to actually do so in current practice.This survey revealed that knowledge about cCMVi among Japanese physicians could be improved and identified variability in clinical practice.

A High Risk of Missing Congenital Cytomegalovirus-Associated Hearing Loss through Newborn Hearing Screening in Japan

It remains unclear to what extent newborn hearing screening (NHS) detects congenital cytomegalovirus (cCMV)-associated sensorineural hearing loss (SNHL) in Japan. This study aimed to clarify the NHS results and audiological characteristics of patients with cCMV-associated SNHL. A total of 541 individuals with unilateral or bilateral hearing loss of unknown etiology were examined for cCMV infection. cCMV infection was defined by the presence of CMV DNA in the dried umbilical cord detected using real-time quantitative PCR. NHS results and audiological data were retrospectively obtained from medical records. Forty-four cases (8.1%) were positive for cCMV infection. Of them, 33 cases underwent NHS and 13 cases (39.4%) passed NHS bilaterally. The pure-tone audiograms of 21 patients were obtained. There were seven cases of unilateral SNHL, five cases of asymmetric bilateral SNHL, and nine cases of symmetric bilateral SNHL. cCMV-related hearing loss is highly heterogeneous, and there is a high risk of missing this condition through NHS.

Intravenous Immune Globulin Uses in the Fetus and Neonate: A Review

Intravenous immune globulin (IVIG) is made after processing plasma from healthy donors. It is composed mainly of pooled immunoglobulin and has clinical evidence-based applications in adult and pediatric populations. Recently, several clinical applications have been proposed for managing conditions in the neonatal population, such as hemolytic disease of the newborn, treatment, and prophylaxis for sepsis in high-risk neonates, enterovirus parvovirus and COVID-19 related neonatal infections, fetal and neonatal immune-induced thrombocytopenia, neonatal hemochromatosis, neonatal Kawasaki disease, and some types of immunodeficiency. The dosing, mechanism of action, effectiveness, side effects, and adverse reactions of IVIG have been relatively well studied in adults but are not well described in the neonatal population. This review aims to provide the most recent evidence and consensus guidelines about the use of IVIG in the fetus and neonate.

Regulation of the MIE Locus During HCMV Latency and Reactivation

Human cytomegalovirus (HCMV) is a ubiquitous herpesviral pathogen that results in life-long infection. HCMV maintains a latent or quiescent infection in hematopoietic cells, which is broadly defined by transcriptional silencing and the absence of de novo virion production. However, upon cell differentiation coupled with immune dysfunction, the virus can reactivate, which leads to lytic replication in a variety of cell and tissue types. One of the mechanisms controlling the balance between latency and reactivation/lytic replication is the regulation of the major immediate-early (MIE) locus. This enhancer/promoter region is complex, and it is regulated by chromatinization and associated factors, as well as a variety of transcription factors. Herein, we discuss these factors and how they influence the MIE locus, which ultimately impacts the phase of HCMV infection.

Efficacy and safety of valganciclovir in patients with symptomatic congenital cytomegalovirus disease: Study Protocol Clinical Trial (SPIRIT Compliant)

BACKGROUND

Congenital cytomegalovirus (CMV) disease, a common mother-to-child infection, can lead to neurological sequelae. Some clinical trials have shown that oral valganciclovir (VGCV) can improve hearing and neurodevelopmental impairment in infants with congenital CMV disease. However, VGCV has neither been approved in Japan nor other countries as a treatment for this disease by the government health insurance.

METHODS

This study is a non-randomized, prospective, open-label, multicenter, single-arm clinical trial and will include subjects meeting the following criteria: confirmation of positive CMV-DNA amplification in urine by an in vitro diagnostic test within 21 days of age; congenital CMV disease with one or more central nervous system disorders-microcephaly, hydrocephalus or ventricular enlargement, periventricular calcification, cortical hypoplasia or white matter injury, retinal choroiditis, and abnormal auditory brainstem response (ABR); and infants within 2 months of age with a gestational age ≥32 weeks at birth and weighing ≥1800 g at the time of registration. Subjects will be orally administered 16 mg/kg VGCV twice daily for 6 months. The target number of cases for enrollment between February 3, 2020 and July 31, 2021 is 25. Primary endpoint is the change in whole blood CMV loads before and after 6 months of treatment. The important secondary endpoint is the change in ABR (both best and total ear hearing assessments) before and after 6 months of treatment. The safety endpoints are adverse events and drug side effects.

DISCUSSION

To the best of our knowledge, this multicenter, open-label, single-arm study will be the first well-designed clinical trial to evaluate the efficacy of oral VGCV in infants with congenital CMV diseases. The findings will reveal the efficacy and safety of oral VGCV treatments and enable the approval of oral VGCV as a treatment for infants with congenital CMV disease by the government health insurance of Japan.