T-Cell Immune Responses in Newborns and Long-Term Sequelae in Congenital Cytomegalovirus Infection (CYTRIC Study)

OBJECTIVE

To assess the role of T-lymphocyte immune responses in newborns with congenital cytomegalovirus (CMV) infection (cCMV) and their potential association with the development of long-term sequelae.

STUDY DESIGN

A multicenter, prospective study from 2017 to 2022 was conducted across eight hospitals in Spain. Blood samples were collected within the first month of life from neonates diagnosed with cCMV. Intracellular cytokine staining was employed to evaluate the presence of CMV-specific interferon-gamma (IFN-γ)-producing CD8+ and CD4+ T lymphocytes (CMV-IFN-γ-CD8+ / CD4+) using flow cytometry. The development of sequelae, including hearing loss and neurologic impairment, was assessed during follow-up.

RESULTS

In total, 64 newborns were included; 42 infants (65.6%) had symptomatic cCMV. The median age at last follow-up visit was 25.3 months (IQR 20.1-34.4). Eighteen infants had long-term sequelae (28.1%), predominantly hearing loss (20.3%) and neurologic disorders (15.6%). No relationship was observed between total count or percentage of CMV-specific IFN-γ-CD8+ or CD4+ lymphocytes and long-term sequelae. Multivariable analysis demonstrated an association between lower total lymphocyte count and long-term sequelae (aOR 0.549, 95% CI: 0.323-0.833), which requires further study.

CONCLUSIONS

CMV-specific IFN-γ-CD4+ and CD8+ T-lymphocyte responses in neonates with cCMV were not predictive of long-term sequelae.

Decidual-tissue-resident memory T cells protect against nonprimary human cytomegalovirus infection at the maternal-fetal interface

Congenital cytomegalovirus (cCMV) is the most common intrauterine infection, leading to infant neurodevelopmental disabilities. An improved knowledge of correlates of protection against cCMV is needed to guide prevention strategies. Here, we employ an ex vivo model of human CMV (HCMV) infection in decidual tissues of women with and without preconception immunity against CMV, recapitulating nonprimary vs. primary infection at the authentic maternofetal transmission site. We show that decidual tissues of women with preconception immunity against CMV exhibit intrinsic resistance to HCMV, mounting a rapid activation of tissue-resident memory CD8+ and CD4+ T cells upon HCMV reinfection. We further reveal the role of HCMV-specific decidual-tissue-resident CD8+ T cells in local protection against nonprimary HCMV infection. The findings could inform the development of a vaccine against cCMV and provide insights for further studies of the integrity of immune defense against HCMV and other pathogens at the human maternal-fetal interface.

Prevention of Congenital Cytomegalovirus Infection: Review and Case Series of Valaciclovir versus Hyperimmune Globulin Therapy

Cytomegalovirus (CMV) is the most common cause of congenital infections in developed countries because is capable of infecting the fetus after both primary and recurrent maternal infection, and because the virus may be spread for years through infected children. Moreover, CMV is the most serious congenital infection associated with severe neurological and sensorineural sequelae, which can occur at birth or develop later on. Hygienic measures can prevent CMV transmission, which mainly involve contact with children under 3 years of age and attending a nursery or daycare. In animal and human pregnancies, many observational and controlled studies have shown that CMV-specific hyperimmune globulin (HIG) is safe and can significantly decrease maternal-fetal transmission of CMV infection and, mostly, the occurrence of CMV disease. Recently, valaciclovir at the dosage of 8 g/day was also reported to be capable of decreasing the rates of congenital infection and disease. However, comparing the results of our two recent case series, the infants born to women treated with HIG showed significantly lower rates of CMV DNA positivity in urine (9.7% vs. 75.0%; p < 0.0001) and abnormalities after follow-up (0.0% vs. 41.7%; p < 0.0001). The implementation of CMV screening would enable primary prevention via hygiene counseling, improve the understanding and awareness of congenital CMV infection, and increase the knowledge of the potential efficacy of preventive or therapeutic HIG or antiviral administration.

Analysis of congenital hearing loss after neonatal hearing screening

Introduction

Neonates undergo neonatal hearing screening to detect congenital hearing loss at an early stage. Once confirmed, it is necessary to perform an etiological workup to start appropriate treatment. The study objective was to assess the different etiologies, risk factors, and hearing results of infants with permanent hearing loss and to evaluate the efficacy and consequences of the different screening devices over the last 21 years.

Methods

We conducted a single-center retrospective cohort analysis for all neonatal hearing screening program referrals and performed an etiological workup in case of confirmed hearing loss. We analyzed the evolution of the etiological protocols based on these results.

Results

The governmental neonatal hearing screening program referred 545 infants to our center. Hearing loss was confirmed in 362 (66.4%) infants and an audiological workup was performed in 458 (84%) cases. 133 (24.4%) infants were diagnosed with permanent hearing loss. Ninety infants (56 bilateral and 34 unilateral) had sensorineural hearing loss, and the degree was predominantly moderate or profound. The most common etiology in bilateral sensorineural hearing loss was a genetic etiology (32.1%), and in unilateral sensorineural hearing loss, an anatomical abnormality (26.5%). Familial history of hearing loss was the most frequently encountered risk factor.

Conclusion

There is a significant number of false positives after the neonatal hearing screening. Permanent hearing loss is found only in a limited number of infants. During the 21 years of this study, we noticed an increase in etiological diagnoses, especially genetic causes, due to more advanced techniques. Genetic causes and anatomical abnormalities are the most common etiology of bilateral and unilateral sensorineural hearing loss, respectively, but a portion remains unknown after extensive examinations.

Effectiveness and safety of prenatal valacyclovir for congenital cytomegalovirus infection: systematic review and meta-analysis

OBJECTIVE

Universal screening for cytomegalovirus (CMV) infection in pregnancy is not recommended in most countries. One of the major deterrents is the lack of effective prenatal therapy. The role of valacyclovir therapy in reducing the risk of vertical transmission, symptomatic congenital CMV infection and adverse outcome is controversial. The main aim of this systematic review and meta-analysis was to investigate the safety and effectiveness of prenatal valacyclovir therapy in pregnancies with maternal CMV infection.

METHODS

MEDLINE, EMBASE and Cochrane databases and ClinicalTrials.gov were searched. The inclusion criteria were pregnancy with confirmed maternal CMV infection, treated or untreated with valacyclovir. The primary outcome was the incidence of congenital CMV infection confirmed by a positive CMV polymerase chain reaction result of the amniotic fluid. The secondary outcomes were symptomatic and asymptomatic infection, perinatal death, termination of pregnancy, anomalies detected on follow-up ultrasound, on fetal magnetic resonance imaging or at birth, severe and mild-to-moderate symptoms due to congenital CMV infection, neurological, visual and hearing symptoms, and adverse events related to valacyclovir. Risk of bias was assessed using the revised Cochrane risk-of-bias tool for randomized trials (RoB 2) or Risk Of Bias In Non-randomized Studies of Interventions (ROBINS-I) tool, as appropriate. Head-to-head meta-analyses were used to compare the risk of each of the explored outcomes according to whether pregnancies with maternal CMV infection were treated with prenatal valacyclovir therapy.

RESULTS

Eight studies (620 women) were included. Pregnancies treated with valacyclovir had a significantly lower risk of congenital CMV infection compared with those not receiving valacyclovir (three studies; 325 fetuses; pooled odds ratio (OR), 0.37 (95% CI, 0.21-0.64); I2  = 0%; P < 0.001). When stratifying the analysis according to gestational age at maternal infection, the risk of vertical transmission was significantly lower in pregnancies receiving valacyclovir following first-trimester maternal infection (three studies; 184 fetuses; pooled OR, 0.34 (95% CI, 0.15-0.74); I2  = 20.9%; P = 0.001), while there was no significant difference between the two groups in those acquiring CMV infection in the periconceptional period or in the third trimester of pregnancy. Only one study reported on the risk of vertical transmission in women infected in the second trimester, demonstrating a lower risk of congenital infection in women taking valacyclovir, although this was based on a small number of cases. Pregnancies treated with valacyclovir therapy had an increased likelihood of asymptomatic congenital CMV infection compared with those not receiving valacyclovir (two studies; 132 fetuses; pooled OR, 2.98 (95% CI, 1.18-7.55); I2  = 0%; P = 0.021), while there was no significant difference between the two groups in the risk of perinatal death (P = 0.923), termination of pregnancy (P = 0.089), anomalies detected at follow-up imaging assessment during pregnancy or at birth (P = 0.934) and symptoms due to CMV infection in the newborn (P = 0.092). The occurrence of all adverse events in pregnant individuals taking valacyclovir was 3.17% (95% CI, 1.24-5.93%) (six studies; 210 women), with 1.71% (95% CI, 0.41-3.39%) experiencing acute renal failure, which resolved after discontinuation of the drug. On GRADE assessment, the quality of evidence showing that valacyclovir reduced the risk of congenital CMV infection and adverse perinatal outcome was very low.

CONCLUSIONS

Prenatal valacyclovir administration in pregnancies with maternal CMV infection reduces the risk of congenital CMV infection. Further evidence is needed to elucidate whether valacyclovir can affect the course of infection in the fetus and the risk of symptomatic fetal or neonatal infection. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Modeling of vertical transmission and pathogenesis of cytomegalovirus in pregnancy: Opportunities and challenges

In addition to facilitating nutrient, oxygen, and waste transfer between developing fetus and mother, the placenta provides important immune barrier function against infection. Elucidation of the complexity of placental barrier function at the maternal-fetal interface has been greatly aided through experimental model organism systems. In this review, we focus on models of vertical transmission of cytomegalovirus (CMV), a ubiquitous double-stranded DNA viruses whose vertical transmission during pregnancy can lead to devastating neurological and obstetric sequelae. We review the current evidence related to guinea pig and murine models of congenital CMV infection, discuss the possible translatability of a non-human primate model, and conclude with recently developed technology using human placental organoids.

Congenital Human Cytomegalovirus Infection Is Associated With Decreased Transplacental IgG Transfer Efficiency Due to Maternal Hypergammaglobulinemia

BACKGROUND

Placentally transferred maternal immunoglobulin G (IgG) protects against pathogens in early life, yet vertically transmitted infections can interfere with transplacental IgG transfer. Although human cytomegalovirus (HCMV) is the most common placentally-transmitted viral infection worldwide, the impact of congenital HCMV (cCMV) infection on transplacental IgG transfer has been underexplored.

METHODS

We evaluated total and antigen-specific maternal and cord blood IgG levels and transplacental IgG transfer efficiency in a US-based cohort of 93 mother-infant pairs including 27 cCMV-infected and 66 cCMV-uninfected pairs, of which 29 infants were born to HCMV-seropositive nontransmitting mothers and 37 to HCMV-seronegative mothers. Controls were matched on sex, race/ethnicity, maternal age, and delivery year.

RESULTS

Transplacental IgG transfer efficiency was decreased by 23% (95% confidence interval [CI] 10-36%, P = .0079) in cCMV-infected pairs and 75% of this effect (95% CI 28-174%, P = .0085) was mediated by elevated maternal IgG levels (ie, hypergammaglobulinemia) in HCMV-transmitting women. Despite reduced transfer efficiency, IgG levels were similar in cord blood from infants with and without cCMV infection.

CONCLUSIONS

Our results indicate that cCMV infection moderately reduces transplacental IgG transfer efficiency due to maternal hypergammaglobulinemia; however, infants with and without cCMV infection had similar antigen-specific IgG levels, suggesting comparable protection from maternal IgG acquired via transplacental transfer.

Universal Newborn Screening for Congenital Cytomegalovirus Infection - From Infant to Maternal Infection: A Prospective Multicenter Study

INTRODUCTION

Most infants at risk for cytomegalovirus (CMV)-associated sensorineural hearing loss (SNHL) are unrecognized because of the absence of a universal neonatal CMV screening. The search of CMV-DNA by molecular methods in salivary swabs was demonstrated to be a reliable approach. This study describes the results obtained by carrying out a universal screening for congenital CMV (cCMV) infection including all live-born newborns in three Italian sites, as well as the therapeutic interventions and clinical outcome of the CMV-infected neonates. Moreover, CMV maternal infection's characteristics were evaluated.

METHODS

To confirm or exclude cCMV infection, a CMV-DNA-positive result on a first salivary swab was followed by repeated saliva and urine samples collected within 21 days of age. Breast milk samples were also collected. The search of CMV-DNA was performed with a single automated quantitative commercial real-time PCR assay, regardless of the type of samples used.

RESULTS

A total of 3,151 newborns were enrolled; 21 (0.66%) of them were congenitally infected (median saliva viral load at screening, 6.65 [range, 5.03-7.17] log₁₀ IU/ml). Very low/low viral load in screening saliva samples (median value, 1.87 [range, 1.14-2.59] log₁₀ IU/ml) was associated with false-positive results (n = 54; 1.7%). CMV-DNA was detected in almost half of the breast milk samples of mother-infant pairs with a false-positive result, suggesting that contamination from breast milk may not be the only explanation in the study population. cCMV infection confirmation with the search of CMV-DNA in a urine sample proved to be the gold standard strategy, since false-positive results were observed in 4/54 (7.5%) of the repeated saliva samples. Symptomatic cCMV infection was observed in 3/21 (14.3%) infants; notably, one (4.7%) developed moderate unilateral SNHL at 5 months after birth. Finally, two symptomatic cCMV infections were associated with primary maternal infection acquired in the first trimester of gestation; one newborn with severe cCMV symptoms was born to a mother with no CMV checkups in pregnancy.

CONCLUSION

Without universal neonatal CMV screening, some infected infants who develop late neurological sequelae may not be recognized and, consequently, they are not able to benefit early from instrumental and therapeutic interventions to limit and/or treat CMV disease.

Diversity of the cochlear and vestibular pathologies in human temporal bones of newborns infected with cytomegalovirus

Hypothesis

Human temporal bones of newborns with congenital cytomegalovirus (cCMV) infection can be characterized by diverse cochlear and vestibular histopathologies associated with the variability in sensorineural hearing loss (SNHL) and vestibular dysfunction in these newborns.

Background

Only a small number of studies on the cochlear and vestibular pathologies in human temporal bones with cCMV infection have been previously reported.

Methods

Cochleovestibular histopathologies were evaluated in 4 temporal bones from 3 infants with cCMV infection by light microscopy.

Results

In one available temporal bone of the infant in Case 1, no cytomegalic cells were found. Large areas of cellular and non-cellular structures were observed in the scala tympani of the perilymphatic space; however, there was no obvious loss of cochlear or vestibular hair cells. In Case 2, cytomegalic cells, a loss of vestibular hair cells, and a loss of nerve fibers were observed only in the area of dark cells in the vestibular labyrinth of the left temporal bone. No cytomegalic cells were found in the right temporal bone of the same infant; however, there was a loss of outer hair cells in the organ of Corti and hypervascularity in the stria vascularis. The one available temporal bone of the infant in Case 3 showed cytomegalic cells and a loss of hair cells in both cochlear and vestibular parts of the inner ear.

Conclusions

Human temporal bones of newborns with cCMV demonstrate diverse cochleovestibular histopathologies. This diversity is consistent with the variable SNHL and vestibular dysfunction reported in infected newborns.

Inclusion of the Guinea Pig Cytomegalovirus Pentameric Complex in a Live Virus Vaccine Aids Efficacy against Congenital Infection but Is Not Essential for Improving Maternal and Neonatal Outcomes

The development of a vaccine against congenital human cytomegalovirus (HCMV) infection is a major priority. The pentameric complex (PC) of virion envelope proteins gH, gL, UL128, UL130, and UL131A is a key vaccine target. To determine the importance of immunity to the homologous PC encoded by guinea pig cytomegalovirus (GPCMV) in preventing congenital CMV, PC-intact and PC-deficient live-attenuated vaccines were generated and directly compared for immunogenicity and efficacy against vertical transmission in a vertical transmission model. A virulent PC-intact GPCMV (PC/intact) was modified by galK mutagenesis either to abrogate PC expression (PC/null; containing a frame-shift mutation in GP129, homolog of UL128) or to delete genes encoding three MHC Class I homologs and a protein kinase R (PKR) evasin while retaining the PC (3DX/Δ145). Attenuated vaccines were compared to sham immunization in a two-dose preconception subcutaneous inoculation regimen in GPCMV seronegative Hartley guinea pigs. Vaccines induced transient, low-grade viremia in 5/12 PC/intact-, 2/12 PC/null-, and 1/11 3DX/Δ145-vaccinated animals. Upon completion of the two-dose vaccine series, ELISA titers for the PC/intact group (geometic mean titer (GMT) 13,669) were not significantly different from PC/null (GMT 8127) but were significantly higher than for the 3DX/Δ145 group (GMT 6185; p < 0.01). Dams were challenged with salivary gland-adapted GPCMV in the second trimester. All vaccines conferred protection against maternal viremia. Newborn weights were significantly lower in sham-immunized controls (84.5 ± 2.4 g) compared to PC/intact (96 ± 2.3 g), PC/null (97.6 ± 1.9 g), or 3DX/Δ145 (93 ± 1.7) pups (p < 0.01). Pup mortality in sham-immunized controls was 29/40 (73%) and decreased to 1/44 (2.3%), 2/46 (4.3%), or 4/40 (10%) in PC/intact, PC/null, or 3DX/Δ145 groups, respectively (all p < 0.001 compared to control). Congenital GPCMV transmission occurred in 5/44 (11%), 16/46 (35%), or 29/38 (76%) of pups in PC/intact, PC/null, or 3DX/Δ145 groups, versus 36/40 (90%) in controls. For infected pups, viral loads were lower in pups born to vaccinated dams compared to controls. Sequence analysis demonstrated that infected pups in the vaccine groups had salivary gland-adapted GPCMV and not vaccine strain-specific sequences, indicating that congenital transmission was due to the challenge virus and not vaccine virus. We conclude that inclusion of the PC in a live, attenuated preconception vaccine improves immunogenicity and reduces vertical transmission, but PC-null vaccines are equal to PC-intact vaccines in reducing maternal viremia and protecting against GPCMV-related pup mortality.

Single Nucleotide Polymorphisms of Interleukins and Toll-like Receptors and Neuroimaging Results in Newborns with Congenital HCMV Infection

Congenital cytomegalovirus infection (cCMV) is the most common intrauterine infection with central nervous system (CNS) involvement. There is limited data on the associations between Single Nucleotide Polymorphisms (SNPs) in genes involving the first-line defense mechanism and the risk of CNS damage during cCMV. We investigated the associations between neuroimaging findings and SNPs in genes encoding the following cytokines and cytokine receptors in 92 infants with cCMV: interleukins (IL1B rs16944, IL12B rs3212227, IL28B rs12979860), C-C motif chemokine ligand 2 (CCL2 rs1024611), dendritic cell-specific intercellular adhesion grabbing non-integrin (DC-SIGN rs735240), Toll-like receptors (TLR2 rs5743708, TLR4 rs4986791, TLR9 rs352140). The SNP of IL1B rs16944 (G/A) was associated with a reduced risk of ventriculomegaly on MRI (OR = 0.46, 95% CI, 0.22-0.95; p = 0.03) and cUS (OR = 0.38, 95% CI, 0.0-0.93; p = 0.034). Infants carrying heterozygous (T/C) genotype at IL28B rs12979860 had an increased risk of cystic lesions on cUS (OR = 3.31, 95% CI, 1.37-8.01; p = 0.0064) and MRI (OR = 4.97, 95% CI, 1.84-13.43; p = 0.001), and an increased risk of ventriculomegaly on MRI (OR = 2.46, 95% CI, 1.03-5.90; p = 0.04). No other associations between genotyped SNPs and neuroimaging results were found. This is the first study demonstrating new associations between SNPs of IL1B and IL28B and abnormal neuroimaging in infants with cCMV.

Human Cytomegalovirus Infection in Women With Preexisting Immunity: Sources of Infection and Mechanisms of Infection in the Presence of Antiviral Immunity

Human cytomegalovirus (HCMV) infection remains an important cause of neurodevelopmental sequelae in infants infected in utero. Unique to the natural history of perinatal HCMV infections is the occurrence of congenital HCMV infections (cCMV) in women with existing immunity to HCMV, infections that have been designated as nonprimary maternal infection. In maternal populations with a high HCMV seroprevalence, cCMV that follows nonprimary maternal infections accounts for 75%-90% of all cases of cCMV infections as well as a large proportion of infected infants with neurodevelopmental sequelae. Although considerable effort has been directed toward understanding immune correlates that can modify maternal infections and intrauterine transmission, the source of virus leading to nonprimary maternal infections and intrauterine transmission is not well defined. Previous paradigms that included reactivation of latent virus as the source of infection in immune women have been challenged by studies demonstrating acquisition and transmission of antigenically distinct viruses, a finding suggesting that reinfection through exposure to an exogenous virus is responsible for some cases of nonprimary maternal infection. Additional understanding of the source(s) of virus that leads to nonprimary maternal infection will be of considerable value in the development and testing of interventions such as vaccines designed to limit the incidence of cCMV in populations with high HCMV seroprevalence.

Blood Viral Load in Symptomatic Congenital Cytomegalovirus Infection

BACKGROUND

Viral loads (VLs) frequently are followed during treatment of symptomatic congenital cytomegalovirus disease, but their predictive value is unclear.

METHODS

Post hoc analysis of 2 antiviral studies was performed. Seventy-three subjects were treated for 6 weeks and 47 subjects were treated for 6 months. Whole blood VL was determined by real-time polymerase chain reaction before and during therapy.

RESULTS

Higher baseline VL was associated with central nervous system involvement (3.82 log, range 1-5.65 vs 3.32 log, range 1-5.36; P = .001), thrombocytopenia (3.68 log, range 1-5.65 vs 3.43 log, range 1-5.36; P = .03), and transaminitis at presentation (3.73 log, range 1-5.60 vs 3.39 log, range 1-5.65; P = .009), but with overlap in the amount of virus detected between groups. In subjects treated for 6 months, lower VL at presentation correlated with better hearing outcomes at 12 months, but VL breakpoints predictive of hearing loss were not identified. Sustained viral suppression during 6 months of therapy correlated with better hearing outcomes at 6, 12, and 24 months (P = .01, P = .0007, P = .04), but a majority without viral suppression still had improved hearing.

CONCLUSIONS

In infants with symptomatic congenital cytomegalovirus disease, higher whole blood VL before initiation of antiviral therapy has no clinically meaningful predictive value for long-term outcomes.

The Natural History of Hearing Disorders in Asymptomatic Congenital Cytomegalovirus Infection

Background and Aim: Cytomegalovirus (CMV) is the main cause of congenital infection in developed countries leading to deafness but the burden of sensorineural hearing loss (SNHL) in asymptomatic children remains incompletely characterized. Aim of this study was to evaluate the long-term audiological outcome in this group of patients. Methods: Consecutive neonates with congenital CMV infection were followed from 2002 to 2018. Patients were considered asymptomatic if free from any clinical and instrumental impairment at referral and underwent serial clinical exams, audiological evaluations and CMV-PCR determinations. Results: A cohort of 258 children was analyzed and the disease onset was asymptomatic in 125 (48%) infants. Among these, we studied 102 patients with a follow-up longer than 1 year and a median observation period of 2.8 years (range: 1-10.3 years). No patient developed a stable delayed SNHL but only 14 (14%) presented a variable hearing impairment, seven of which bilateral. The unstable SNHL was mild in 12 infants and moderate in two. Patients with fluctuating SNHL had significantly higher urine viral load (p 0.002) and more often positive viremia (p 0.015) than babies with stable normal hearing. Conclusions: CMV infected, asymptomatic neonates have a low risk of transient SNHL later in infancy. Positive viremia and high urine viral load at onset are significant risk factors for delayed fluctuating SNHL. These data are relevant for an appropriate follow up plan of these patients.

Congenital Cytomegalovirus Infection: Maternal-Child HLA-C, HLA-E, and HLA-G Affect Clinical Outcome

Congenital CMV infection (cCMV) is the most common congenital infection causing permanent long-term impairments (LTI). cCMV immunopathogenesis is largely unknown due to the complex interplay between viral, maternal, placental, and child factors. In this study, a large retrospective nationwide cohort of children with cCMV and their mothers was used. HLA-C, HLA-E, and HLA-G were assessed in 96 mother–child pairs in relation to symptoms at birth and LTI at 6 years of age. The mothers were additionally typed for killer cell immunoglobulin-like receptors. The maternal HLA-G 14 bp deletion/deletion polymorphism was associated with a worse outcome, as the immunomodulation effect of higher protein levels may induce less CMV control, with a direct impact on placenta and fetus. The absence of maternal HLA-C belonging to the C2 group was associated with symptoms at birth, as activating signals on decidual NK may override inhibitory signals, contributing to a placental pro-inflammatory environment. Here, the increased HLA-E*0101 and HLA-C mismatches, which were associated with symptoms at birth, may enhance maternal allo-reactivity to fetal Ags, and cause suboptimal viral clearance. Finally, HLA-C non-inherited maternal antigens (NIMAs) were associated with LTI. The tolerance induced in the fetus toward NIMAs may indirectly induce a suboptimal CMV antiviral response throughout childhood. In light of our findings, the potential role of maternal–child HLA in controlling CMV infection and cCMV-related disease, and the clinical value as predictor for long-term outcome certainly deserve further evaluation.

High Cytomegalovirus (CMV) DNAemia Predicts CMV Sequelae in Asymptomatic Congenitally Infected Newborns Born to Women With Primary Infection During Pregnancy

OBJECTIVE

We investigated the kinetics of cytomegalovirus (CMV) clearance in blood and urine and the relationship between the viral load in blood at birth and the development of late-onset sequelae in asymptomatic congenital CMV infection.

METHODS

Thirty-three newborns with congenital asymptomatic CMV infection born to women with primary CMV infection during pregnancy were enrolled. CMV infection was monitored by polymerase chain reaction analysis of blood and urine. The follow-up examination was concluded at 6 years of age.

RESULTS

Ten infants developed postnatal sequelae, whereas twenty-three infants remained asymptomatic. Fifty percent of babies cleared CMV in blood and urine within 3 and 36 months, respectively. Logistic multivariate regression revealed that the risk of neonatal clinical disease crossed the level of 50% with a DNAemia at birth of ≥ 12,000 copies/mL (P = .0002). The risk of hearing deficit crossed the level of 50% with a DNAemia at birth of ≥ 17,000 copies/mL (P = .0001). No significant difference was found between the kinetics of CMV clearance in asymptomatic children as compared to babies with late-onset disease.

CONCLUSIONS

Asymptomatic newborns with a CMV DNAemia at birth of ≥ 12,000 copies/mL were more likely to experience CMV-related sequelae. The risk of hearing deficit increased with a viral load in blood of ≥ 17,000 copies/mL.