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.

Identifying high-confidence variants in human cytomegalovirus genomes sequenced from clinical samples.

Understanding the intrahost evolution of viral populations has implications in pathogenesis, diagnosis, and treatment and has recently made impressive advances from developments in high-throughput sequencing. However, the underlying analyses are very sensitive to sources of bias, error, and artefact in the data, and it is important that these are addressed adequately if robust conclusions are to be drawn. The key factors include (1) determining the number of viral strains present in the sample analysed; (2) monitoring the extent to which the data represent these strains and assessing the quality of these data; (3) dealing with the effects of cross-contamination; and (4) ensuring that the results are reproducible. We investigated these factors by generating sequence datasets, including biological and technical replicates, directly from clinical samples obtained from a small cohort of patients who had been infected congenitally with the herpesvirus human cytomegalovirus, with the aim of developing a strategy for identifying high-confidence intrahost variants. We found that such variants were few in number and typically present in low proportions and concluded that human cytomegalovirus exhibits a very low level of intrahost variability. In addition to clarifying the situation regarding human cytomegalovirus, our strategy has wider applicability to understanding the intrahost variability of other viruses.

Literature Review and an Italian Hospital Experience about Post-Natal CMV Infection Acquired by Breast-Feeding in Very Low and/or Extremely Low Birth Weight Infants.

Breastfeeding is recommended for all neonates due to a known variety of beneficial effects, but infants can be infected by cell-associated bacteria and viruses from breast milk, such as cytomegalovirus (CMV). The majority of CMV-seropositive breastfeeding women have a viral, self-restricted reactivation, can shed the virus in the milk for about 12 weeks after delivery, and can transmit the infection to their offspring. Post-natal CMV-infected term infants are mainly asymptomatic, while very low birth weight (VLBW, <1500 g) and extremely low birth weight (ELBW, <1000 g) infants may present with severe disease, short-term sequelae ranging from abnormalities in laboratory indexes to sepsis-like syndrome, and long-term sequelae such as developmental problems. Thus, the use of thermally treated maternal milk for VLBW/ELBW infants may be indicated to prevent/reduce the risk of CMV transmission. Different techniques, with varying efficacy in eradicating CMV and maintaining the activity of biological compounds in milk are available: long/short pasteurization, freeze-thawing, the use of microwaves, and ultraviolet-C irradiation. In our NICU, the use of maternal raw milk is always strongly recommended for term/preterm infants, but to reduce risk of CMV transmission, freeze-thawing mother's own milk is used in neonates with GA ≤ 30 weeks or/and weight ≤ 1000 g, usually regardless of serological maternal condition, as CMV screening is not routinely offered to pregnant women and the milk of seroimmune mothers is not evaluated for CMV reactivation, as its rate is similar to seroprevalence. Over the last 4 years, we had 10 VLBW/ELBW newborns in our NICU with late-onset sepsis and negative cultures. In these cases, the research of CMV DNA in neonatal urine or saliva, for the diagnosis of post-natal symptomatic infection (once congenital transmission has been excluded) may be useful and not invasive. The take-home message we would like to share is that acquired CMV infection should be considered in VLBW/ELBW infants breastfed by seropositive mothers and presenting severe symptoms-particularly sepsis with negative cultures. This could allow pediatricians to make better-quality diagnoses, perform supportive therapy, provide antiviral treatment if needed, or establish a "pre-emptive" therapy for these high-risk neonates.

Cytomegalovirus-Specific T Cell Epitope Recognition in Congenital Cytomegalovirus Mother-Infant Pairs.

Background: Congenital cytomegalovirus (cCMV) infection is the most common infection acquired before birth and from which about 20% of infants develop permanent neurodevelopmental effects regardless of presence or absence of symptoms at birth. Viral escape from host immune control may be a mechanism of CMV transmission and infant disease severity. We sought to identify and compare CMV epitopes recognized by mother-infant pairs. We also hypothesized that if immune escape were occurring, then one pattern of longitudinal CD8 T cell responses restricted by shared HLA alleles would be maternal loss (by viral escape) and infant gain (by viral reversion to wildtype) of CMV epitope recognition. Methods: The study population consisted of 6 women with primary CMV infection during pregnancy and their infants with cCMV infection. CMV UL83 and UL123 peptides with known or predicted restriction by maternal MHC class I alleles were identified, and a subset was selected for testing based on several criteria. Maternal or infant cells were stimulated with CMV peptides in the IFN-γ ELISpot assay. Results: Overall, 14 of 25 (56%; 8 UL83 and 6 UL123) peptides recognized by mother-infant pairs were not previously reported as CD8 T cell epitopes. Of three pairs with longitudinal samples, one showed maternal loss and infant gain of responses to a CMV epitope restricted by a shared HLA allele. Conclusions: CD8 T cell responses to multiple novel CMV epitopes were identified, particularly in infants. Moreover, the hypothesized pattern of CMV immune escape was observed in one mother-infant pair. These findings emphasize that knowledge of paired CMV epitope recognition allows exploration of viral immune escape that may operate within the maternal-fetal system. Our work provides rationale for future studies of this potential mechanism of CMV transmission during pregnancy or clinical outcomes of infants with cCMV infection.

Onset of valganciclovir resistance in two infants with congenital cytomegalovirus infection.

Ganciclovir and its prodrug valganciclovir are elective treatments for cCMV. Neonates with important symptoms undergo 6 months of therapy to ameliorate/prevent symptoms and late sequelae, but evidence of resistance is emerging. Over the last 5 years, we took care of 59 cCMV infants and experienced two cases of resistance among nine cCMV infants receiving long-term valganciclovir therapy. In the first case, valganciclovir therapy was prolonged beyond 6 months due to severity of symptoms, control of viral load, and absence of adverse events. Resistance was detected in the 8th month of therapy. In the second case, after a significant reduction following valganciclovir administration and no adverse events, CMV viral load suddenly increased in the 6th month of therapy due to resistance. Both events were associated with UL97 gene mutation. The cCMV infants, affected by severe symptoms, remained in a steady state during treatment, and their later neurological development was coherent with initial seriousness of diagnosis. Prolonged therapeutic exposure may therefore be a risk for resistance, suggesting that constant dosage/weight adjustments, monthly surveillance of viral load, and therapeutic drug monitoring could be proposed to monitor resistance onset and optimize the therapy regime. The risk-benefit ratio for long-term therapy, including the possibility of resistance onset, alongside SNHL and neurodevelopmental improvement, should also be evaluated.

Zika Virus Infection in Pregnancy: Advanced Diagnostic Approaches in Dengue-Naive and Dengue-Experienced Pregnant Women and Possible Implication for Cross-Reactivity and Cross-Protection.

Zika virus (ZIKV) infection has been linked to congenital defects in fetuses and infants, as exemplified by the microcephaly epidemic in Brazil. Given the overlapping presence of Dengue virus (DENV) in the majority of ZIKV epidemic regions, advanced diagnostic approaches need to be evaluated to establish the role of pre-existing DENV immunity in ZIKV infection. From 2015 to 2017, five pregnant women with suspected ZIKV infection were investigated in Pavia, Italy. Among the five pregnant women, three were DENV-ZIKV immunologically cross-reactive, and two were DENV-naïve. Advanced diagnosis included the following: (i) NS1 blockade-of-binding (BOB) ELISA assay for ZIKV specific antibodies and (ii) ELISpot assay for the quantification of effector memory T cells for DENV and ZIKV. These novel assays allowed to distinguish between related flavivirus infections. The three DENV-experienced mothers did not transmit ZIKV to the fetus, while the two DENV-naive mothers transmitted ZIKV to the fetus. Pre-existing immunity in DENV experienced mothers might play a role in cross-protection.

Neonatal HCMV-related polymicrogyria in seroimmune women: What is the optimal pregnancy management?

BACKGROUND: Human cytomegalovirus (HCMV) infection is the most common congenital infection in developed countries. Recent studies highlighted similar percentages of symptoms in HCMV congenitally-infected infants following either primary or non-primary maternal infections. OBJECTIVES: To highlight correlation between neonatal brain abnormalities, detected by ultrasounds and magnetic resonance image in HCMV congenitally-infected infants, and maternal virological parameters during pregnancy, especially in seroimmune mothers. STUDY DESIGN: We considered the 36 HCMV congenitally-infected infants (26 asymptomatic and 10 symptomatic) referred to our center over 4 consecutive years. Maternal serologic data during pregnancy were available for all cases. Neonatal cranial ultrasound and magnetic resonance images were related to maternal virological findings during pregnancy. RESULTS: Polymicrogyria was observed in 6/10 (60.0%) symptomatic and 0/26 (0%) asymptomatic newborns (p < 0.001). The 6 infants with polymicrogyria were all born to mothers who were HCMV IgG reactive with negative specific IgM, in the first trimester of pregnancy (range: 8-14 weeks). For these six women, pre-conceptional HCMV serologic information were absent and they all were considered immune for HCMV during pregnancy, therefore no further serologic investigation or specific educational and hygienic information were recommended during gestation. CONCLUSION: These data highlight the elevated frequency of polymicrogyria in HCMV congenitally-infected infants born to mothers defined as seroimmune in the early stage of pregnancy and having no pre-existing serologic information. The paper stresses the potential utility of pre-conceptional screening to define maternal infection reliably (primary vs non-primary), and allow evidence-based counseling in women with positive serology, suggesting also preventive hygienic measures during pregnancy.

An Italian Prospective Experience on the Association Between Congenital Cytomegalovirus Infection and Autistic Spectrum Disorder.

The aim of this retrospective study, with prospective data collection, was to correlate congenital cytomegalovirus (CMV) infection with autism spectrum disorder (ASD) and to define its prevalence. Seventy proven congenitally-infected infants, born between 2007 and 2012, were referred to our centre for CMV diagnosis and follow-up, which consisted of a consolidated protocol allowing an early evaluation of autism. We considered four children 2-year old, two of whom, at the age of 3, were diagnosed with ASD demonstrating a 2-3 fold higher prevalence (2.86%), than that in general Italian population (0.66-1.36%).Our protocol enabled us to make the earliest diagnosis and highlight the role of the virus among other causes of autism, which may be a long term sequela of congenital CMV.

Risk of congenital disease in 46 infected fetuses according to gestational age of primary human cytomegalovirus infection in the mother.

Given the difficulty in establishing the exact time of HCMV transmission from mother to fetus, HCMV intrauterine infection was investigated in 46 infected fetuses/newborns by correlating maternal and fetal parameters with clinical outcome according to the time interval between the onset of maternal infection and prenatal diagnosis. In detail, 17/28 (60.7%) asymptomatic and 18/18 (100%) symptomatic fetuses/newborns were infected as a consequence of a primary maternal HCMV infection acquired ≤8 weeks of gestational age, while 11/28 (39.3%) asymptomatic and 0/18 (0%) symptomatic fetuses/newborns were congenitally infected when maternal infection was acquired >8 weeks' gestation. Symptomatic fetal infections appeared to be associated with a maternal primary infection occurring at ≤ 8 weeks' gestation. Cordocentesis performed at 20 weeks' gestation should be restricted to high risk infected fetuses.

Maternal, fetal, and neonatal parameters for prognosis and counseling of HCMV congenital infection.

To investigate retrospectively the prognostic significance of maternal, fetal, and neonatal parameters and clinical outcome in 150 HCMV congenital infections during the period 1995-2009. HCMV fetal infection was investigated in amniotic fluid and fetal blood samples. HCMV congenital infection was confirmed in newborn urine and blood samples. Symptomatic infection was defined in HCMV-infected fetuses and in infected newborns on the basis of physical and instrumental findings. Follow-up at 3, 6, 12 months, and then annually up to school age, included clinical evaluation, funduscopic, audiologic, neurologic, and cognitive assessment. Overall, 122/150 (81.3%) newborns were asymptomatic and 28/150 (18.7%) were symptomatic at birth. The best prognostic maternal parameter of symptomatic infection at birth was gestational age at infection (P = 0.037). The best fetal virological markers were HCMV DNA levels in amniotic fluid (P < 0.001), antigenaemia levels (P = 0.007), HCMV DNA levels in blood (P = 0.004), and HCMV-specific IgM index values (P = 0.002). The only significant neonatal parameter was HCMV DNA level in blood [P = 0.006; OR, 3.62 (95% CI, 1.46-8.97)]. Symptoms at birth correlated significantly with long-term sequelae (P = 0.021). A trend towards a risk of sequelae in early (n = 15/58 examined) versus late (n = 6/57 examined) maternal infection was documented. The risk of symptomatic congenital infection at birth increased linearly with the number of significant maternal, fetal, and neonatal parameters.

Diagnosis and counseling of fetal and neonatal HCMV infection.

Fetal HCMV infection is investigated by amniocentesis when a maternal primary infection is diagnosed or ultrasound (US/MRI) abnormalities are observed. In fetal blood, prognostic markers of symptomatic congenital infection may be evaluated for parental counseling. At birth, viral load measurement in body fluids may correlate with long-term sequelae, but the prognostic accuracy of symptomatic infection increases when maternal, fetal, and neonatal parameters are combined.

Pharmacokinetics, pharmacodynamics and clinical use of valganciclovir in newborns with symptomatic congenital cytomegalovirus infection.

Congenital cytomegalovirus infection is the most common cause of nonhereditary sensorineural hearing loss and an important cause of psychomotor retardation. Newborns suffering from symptomatic congenital cytomegalovirus infection have been typically treated with i.v. ganciclovir (GCV). Nowadays valganciclovir (V-GCV), a mono-valyl ester pro-drug of GCV, is available as an oral syrup. The existing literature demonstrated that V-GCV is well absorbed from the gastrointestinal tract and is rapidly converted into GCV in the intestinal wall and liver. The mechanism of antiviral action is the same that has been described for GCV. All these characteristics make this formulation particularly suitable for the symptomatic congenitally infected newborns. In neonates, V-GCV oral formulation proved stable and constant GVC plasma concentrations, in the suggested therapeutic range. The syrup demonstrated to be clinically effective and well tolerated and to be appropriate for a prolonged post-discharge therapy avoiding the discomfort of hospitalization, reducing the risk for nosocomial infections and decreasing the cost for the National Health Service. This article reviews all the available literature about V-GCV syrup in the treatment of newborns and infants with congenital CMV infection with the regard to pharmacokinetics, pharmacodynamic properties and clinical use, focussing on new data and on our experience.

Breast milk-acquired cytomegalovirus infection in very low birth weight infants.

Perinatal transmission of human cytomegalovirus (HCMV) infection in very low birth weight (VLBW) premature infants can lead to serious clinical symptoms and it has ben increasingly recognized that breast milk is the most frequent route of transmission. Breast milk is considered ideal food for newborns because of its nutritional value and anti-infectious components, but it can also be vehicle for viral and bacterial infection. The majority of HCMV seropositive mothers shed the virus into their breast milk and can transmit infection to their offspring. Perinatally acquired infections in full-term neonates are usually asymptomatic without sequelae due to protective maternal HCMV-specific antibodies received during pregnancy. In contrast, VLBW preterm infants are at risk of symptomatic infection with neutropaenia, thrombocytopaenia, sepsis-like syndrome and, less frequently, pneumonia and enteric infection. Postnatally acquired infection seems to spontaneously resolve without altering the clinical outcome. Ganciclovir treatment is restricted to severe symptomatic infections. Preterm infants with a gestational age <30 weeks, or with a birth weight <1000 g, are at greater risk of severe postnatal symptomatic HCMV infection, transmitted via maternal milk. The pasteurization of breast milk entirely eliminates infectivity and prevents virus transmission but alters nutritional and immunological milk properties, and freezing reduces, but does not eradicate, infectivity. Most authors encourage fresh maternal breastfeeding because its beneficial effects outweigh the risk of a transient infection, sequelae-free. Nevertheless, an individual decision based on the condition of health of the infant is important.

Congenital cytomegalovirus infection: treatment, sequelae and follow-up.

Cytomegalovirus (CMV) is the most common cause of congenital infection affecting about 1% of all the live births worldwide. Its prevalence in the developed world seems to be slightly lower, ranging between 0.6 and 0.7%. Symptoms can be detected at birth in 10-15% of the congenitally infected of which 50-90% will develop sequelae, the most frequent being sensorineural hearing loss (SNHL), visual defect, psychomotor impairment, mental retardation, cerebral palsy and seizures. Eighty-five to 90% of the infected newborns are asymptomatic but 10-15% of them are equally at risk for sensorineural sequelae, like 20-30% of all the infected children. Therefore it is important a time prolonged and closer follow-up of infected children that we propose should be until 6 years of age. This should lead to an early intervention, better management and eventually even control the long-term sequelae. Infants born with symptomatic congenital infection have a worse prognosis than those with no evidence of clinical disease, and ganciclovir (GCV) intravenous 6 mg/kg every 12 h for 6 weeks is the most used therapy for symptomatic newborns. Valganciclovir (V-GCV) syrup is a pro-drug of GCV and presents high oral bioavailability. To date, it is possible to administer this drug at home, and the tolerability profile may allow for wider indications and longer treatments.

From apneic spells to the development of hypertensive hydrocephalus: a case report of homocystinuria with early onset.

Homocystinuria represents a group of hereditary metabolic disorders characterized by an accumulation of homocysteine in the serum and an increased excretion of homocysteine in the urine. The infantile form is severe: the main clinical findings are neurologic signs, associated with hematological signs and bone alterations. Immediate restoration of plasma amino acids is the primary goal and early diagnosis is crucial not to delay the onset of possible treatment. We report a case of homocystinuria with early onset: an initial symptomatology was undervalued by the pediatrician with a delay in diagnosis. Despite the therapy, the patient developed tetraventricular hydrocephalus requiring ventricular drainage. In conclusion, we want to remember the necessity to perform a complete metabolic workup in a patient with clinical manifestations suggestive for homocystinuria, and the importance of early recognition of the signs and symptoms of hypertensive hydrocephalus, a possible complication of this condition.