New advances in the diagnosis of congenital cytomegalovirus infection

Intrauterine therapy of cytomegalovirus infection with valganciclovir: review of the literature

Congenital cytomegalovirus (CMV) infection is the leading cause for sensorineural hearing loss and mental retardation in children without genetic diseases worldwide. There is little evidence guiding therapeutic strategies during pregnancy when intrauterine fetal CMV infection is confirmed. We provide a systematic review of the use of ganciclovir (GCV) or VGCV during pregnancy discussing safety of its use for mother and fetus and describe two cases of intrauterine therapy of fetal CMV infection with valganciclovir (VGCV). A PubMed database search was done up to November 16, 2016 without any restrictions of publication date or journal, using the following keywords: "valganciclovir" or "ganciclovir" and "pregnan*". Furthermore, citations were searched and expert references were obtained. Reported cases were considered if therapy was in humans and initiation of treatment of the CMV infection was during pregnancy. In total, seven case reports were retrieved which described GCV or VGCV use during pregnancy for fetal or maternal CMV infection. In the four cases of treatment for maternal CMV infection, no negative effects on the fetus were reported. Three cases of GCV administration to pregnant woman with the intention of fetal treatment after proven fetal infection were found. We additionally present two cases of VGCV treatment in pregnancy from our center of tertiary care. VGCV seems to be a safe treatment for congenital CMV infection for the mother and the fetus. Therapeutic concentrations can be achieved in the fetus by oral intake of the mother and CMV replication can be suppressed. Larger studies are needed to evaluate this therapeutic intervention and the long-term effects.

Sequence and Timing of Intracranial Changes in Cytomegalovirus in Pregnancy: A Case Report and Literature Review

Cytomegalovirus (CMV) is the most common cause of intrauterine infection, occurring in up to 2% of all live births. Most women are asymptomatic or experience nonspecific symptoms, which can lead to long-term sequelae in newborns including neurological impairment, hearing loss, and mental retardation. A 41-year-old woman (G6 P2), with a medical history of epilepsy, presented for her routine anomaly scan at 20 + 4/40. A single finding of echogenic bowel was noted on ultrasound which prompted a full investigation. A repeat ultrasound only five days later demonstrated progressive changes, which included bilateral ventriculomegaly with oedema of the posterior ventricular wall, periventricular hyperechogenicity, and enlargement of the cisterna magna. CMV DNA was detected at amniocentesis. Ultrasound findings are not diagnostic for CMV with only 11-15% of at-risk fetuses being identified. Unfortunately, these findings may be the only indication of an abnormality. There is a well-documented lack of awareness surrounding CMV and screening is not routinely offered. Given the risk to the pregnancy of CMV and to subsequent pregnancies, simple education at the start of a pregnancy could significantly reduce the incidence of maternal CMV.

Positive IgM in Congenital CMV Infection

Neonatal serum detection of cytomegalovirus (CMV) immunoglobulin M (IgM) has low sensitivity in identifying congenital cytomegalovirus (cCMV). Several reports have endeavored to associate the presence/absence of IgM to disease severity. Data were collected for all infants with cCMV followed in our clinic. Infant outcome after birth was compared between infants who tested positive or negative. Sensitivity of positive IgM in diagnosing cCMV was 40.7%. The rate of symptomatic disease in those who tested positive was statistically higher (67.7%, P < .001). Odds ratio for symptomatic disease in infants with positive IgM born after a maternal primary infection was 3.47 (95% confidence interval = 1.7-7.1). Positive IgM was found in only 48.8% of symptomatic and 22.1% of asymptomatic children. Our results demonstrated a low sensitivity of IgM in diagnosing cCMV. However, while a positive IgM antibody for CMV is associated with a more symptomatic disease, it does not serve as a precise laboratory marker for a severity.

Cytomegalovirus infection in pregnancy

Cytomegalovirus (CMV) is a DNA herpesvirus that is common worldwide. The two known main sources of primary CMV infection during pregnancy are through sexual activity and contact with young children. Primary infection occurs in approximately 1 to 4% of pregnancies, and is mostly asymptomatic in immunocompetent adults. However, primary infection may manifest as a mild mononucleosis or flu-like syndrome with persistent fever and fatigue. CMV can be transmitted from mother-to-child in utero, intrapartum, or during breastfeeding. Intrauterine transmission can lead to congenital CMV infection, a leading cause of permanent hearing and vision loss and neurological disability among children. Congenital CMV transmission rates are as high as 50% in women who acquire primary CMV infection during pregnancy, and less than 2% in women with nonprimary infection. There is no licensed CMV vaccine. Good hygiene practices and avoiding intimate contact with young children (e.g., kissing on the mouth and sharing utensils) have been suggested as an approach to prevent maternal primary CMV infection during pregnancy, but remains an unproven method of reducing the risk of congenital CMV infection. Approximately 1 in 10 infants who acquire CMV in utero will have clinical signs at birth, and an additional 10 to 15% will go on to develop late-onset sequelae. Antiviral treatment prenatally and postnatally has not proven effective at preventing congenital or postnatal CMV infection, and is not recommended for routine clinical care. However, antiviral treatment when initiated in the first month of life for symptomatic congenital CMV infection is recommended for improved neurodevelopmental and audiologic outcomes. Birth Defects Research 109:336-346, 2017. © 2017 Wiley Periodicals, Inc.

Presence of Cytomegalovirus in urine and blood of pregnant women with primary infection might be associated with fetal infection

BACKGROUND

Cytomegalovirus (CMV) congenital infection can result from primary infection, reinfection or reactivation among pregnant women. The risk of vertical transmission is much higher in case of primary infection, and the transmission rate increases with gestational age. However there are still many questions about maternal markers that can predict whether the virus will be transmitted to the fetus.

OBJECTIVES

To investigate the relationship between the presence and the quantity of CMV in urine and blood of women presenting a primary CMV infection during pregnancy and the presence of congenital infection in their offspring.

STUDY DESIGN

Detection and quantification of CMV DNA was performed on 150 urine samples and 114 blood samples from 150 pregnant women with proven CMV primary infection.

RESULTS

Transmission rate was 36.7% (55/150). A statistically significant association was found between the presence of CMV in maternal urine and newborn infection (OR 2.03 95%CI 1.03-3.99). A clearly significant association was found between the presence of CMV in maternal blood and newborn infection (OR 3.14 95% CI 1.38-7.16). Taking into consideration those samples that are positive for CMV in maternal urine, the median value of viral load was significantly higher in those patients who transmitted to offspring (P=0.015). No significant association between viral load in maternal blood and newborn infection was observed.

CONCLUSION

The presence of CMV in maternal urine and maternal blood correlated to the transmission of CMV to offspring in our cohort. The median viral load in urine is higher in women who transmitted. These markers may help to identify pregnant women at risk to transmit to the fetus.

Symptomatic congenital cytomegalovirus disease following non-primary maternal infection: a retrospective cohort study

Background

Scarce data exist about screening, diagnosis and prognosis of non-primary Cytomegalovirus (CMV) during pregnancy. We aimed to examine antenatal diagnosis of maternal non-primary CMV infection and to identify risk factors for congenial CMV disease.

Methods

Retrospective cohort of 107 neonates with congenital symptomatic CMV infection, following either primary (n = 95) or non-primary (n = 12) maternal CMV infection. We compared the groups for the manifestations and severity of congenial CMV disease, as well as for possible factors associated with the risk of developing CMV related infant morbidity.

Results

Disease severity is not similar in affected newborns, with a higher incidence of abnormal brain sonographic findings, following primary versus non-primary maternal CMV infection (76.8% vs. 8.3%, p < .001). Symptomatic congenital CMV disease following a non-primary infection is more frequent if gestational hypertensive disorders and/or gestational diabetes mellitus have ensued during pregnancy (33.3% vs. 9.9%, p <0.038), as well as if any medications were taken throughout gestation (50% vs. 16.8%, p <0.016). CMV-IgM demonstrates a low detection rate for non-primary maternal infection during pregnancy compared to primary infection (25% vs. 75.8%, p = 0.0008).

Conclusion

Non-primary maternal CMV infection has an impact on the neonate. Although not readily diagnosed during pregnancy, knowledge of risk factors may aid in raising clinical suspicion.

Toward an Algorithm for the Diagnosis and Management of CMV in Patients with Colitis

INTRODUCTION

Concurrent cytomegalovirus (CMV) in inflammatory bowel disease-related colitis is an important yet complex clinical scenario associated with high rates of colectomy and other morbidity. This review aimed to examine the literature to produce a comprehensive diagnostic and treatment algorithm for the management of CMV in patients with colitis.

METHODS

A systematic literature review was conducted via PubMed/Medline databases until August 31, 2015, using multiple keywords in English language and where original data only presented.

RESULTS

This review discusses the concept of CMV reactivation which frequently occurs in inflammatory bowel disease-related colitis, most commonly in those presenting with steroid-refractory colitis. In this context, although signifying a poorer prognosis, in most cases, the virus is nonpathogenic and thus antiviral treatment is unhelpful. However, when reactivation gives rise to true CMV disease (colitis) as best discriminated by histology with immunohistochemistry (and the density of such) in colonic biopsy tissue, the patient does benefit from antivirals.

CONCLUSION

Diagnostic-based patient selection and treatment is integral to optimal outcomes in CMV, and therefore we propose an algorithm based on these concepts that now requires prospective evaluation.

Prediction of Congenital Cytomegalovirus Infection in High-Risk Pregnant Women

BACKGROUND

This prospective study aimed to determine maternal clinical, laboratory, and ultrasound findings that effectively predict the occurrence of congenital cytomegalovirus (CMV) infection (CCI) in high-risk pregnant women.

METHODS

Three hundred CMV immunoglobulin (Ig) M-positive pregnant women were enrolled. The maternal clinical and laboratory findings, including serum CMV IgM and IgG; IgG avidity index (AI); antigenemia assay (C7-HRP); polymerase chain reaction (PCR) for the detection of CMV-DNA in the maternal serum, urine, and uterine cervical secretion; and prenatal ultrasound findings, were evaluated. To determine predictive factors for the occurrence of CCI, logistic regression analyses were performed.

RESULTS

In 22 of the 300 women, CCI was confirmed using PCR for CMV-DNA in newborn urine. Univariate analyses demonstrated that the presence of maternal flu-like symptoms, presence of ultrasound fetal abnormalities, serum titers of CMV IgM, positive results for C7-HRP, CMV IgG AI <40%, and positive PCR results in the uterine cervical secretion were statistically associated with the occurrence of CCI. Multivariable analysis revealed that the presence of ultrasound fetal abnormalities (odds ratio [OR], 31.9; 95% confidence interval [CI], 8.5-120.3; P < .001) and positive PCR results in the uterine cervical secretion (OR, 16.4; 95% CI, 5.0-54.1; P < .001) were independent predictive factors of CCI in CMV IgM-positive women.

CONCLUSIONS

This is the first prospective cohort study to suggest that the presence of CMV-DNA in the maternal uterine cervical secretion and ultrasound fetal abnormalities are predictive of the occurrence of congenital CMV infection in high-risk pregnant women.

Diagnosis, gB genotype distribution and viral load of symptomatic congenitally infected CMV patients in Cuba

OBJECTIVE

Cytomegalovirus (CMV) is the leading cause of viral congenital infection. Some viral factors have been proposed to be CMV pathogenicity markers. The objective of this study was to investigate the frequency of congenital CMV infection in symptomatic patients and the possible association with the CMV glycoprotein B (gB) genotype and viral load.

STUDY DESIGN

A total of 361 newborns (NB) and 158 pregnant women (PW) with clinically suspected CMV infection were enrolled. Studied samples included urine, saliva, serum, vaginal swabs and amniotic fluid. CMV infection was diagnosed by multiplex nested PCR. CMV gB genotyping was performed on infected samples, followed by viral load determination.

RESULTS

Overall, 18.7% of the tested patients were positive for CMV infection, 19.7% of NB were congenitally infected and 16.5% of PW showed active CMV infection. gB-2 was the most prevalent genotype detected (39/97 patients). gB CMV mixed infections were detected in 12 patients. gB-2 was associated with mono-infections (P<0.01). Mixed infections showed higher levels of viral load compared with gB mono-infection (P=0.03). Hepatomegaly, splenomegaly, jaundice, sepsis-like syndrome and malformations were the most prevalent clinical findings. gB-4 was more frequently associated with sepsis-like syndrome than other gB genotypes (P=0.04, odds ratio=4.3, confidence interval: 0.9 to 21.6). The difference in medians of CMV load was statistically significant among patients presenting different clinical signs (P=0.04).

CONCLUSIONS

This study showed that CMV is a frequent cause of congenital infection in symptomatic Cuban patients. Despite gB2 being the most frequently detected, gB-4 was the only genotype associated with clinical features (sepsis-like syndrome in NB). No other associations among specific genotypes and clinical characteristics were found. Further studies are needed to clarify the role that viral load and genotype play in the outcome of congenital infection.

Study of Soluble HLA-G in Congenital Human Cytomegalovirus Infection

Human leukocyte antigen-G (HLA-G) is a nonclassical HLA class I antigen that is expressed during pregnancy contributing to maternal-fetal tolerance. HLA-G can be expressed as membrane-bound and soluble forms. HLA-G expression increases strongly during viral infections such as congenital human cytomegalovirus (HCMV) infections, with functional consequences in immunoregulation. In this work we investigated the expression of soluble (s)HLA-G and beta-2 microglobulin (component of HLA) molecules in correlation with the risk of transmission and severity of congenital HCMV infection. We analyzed 182 blood samples from 130 pregnant women and 52 nonpregnant women and 56 amniotic fluid samples from women experiencing primary HCMV infection. The median levels of sHLA-G in maternal serum of women with primary HCMV infection were higher in comparison with nonprimary and uninfected pregnant women (p < 0.001). AF from HCMV symptomatic fetuses presented higher sHLA-G levels in comparison with infected asymptomatic fetuses (p < 0.001), presence of HLA-G free-heavy chain, and a concentration gradient from amniotic fluid to maternal blood. No significant statistical difference of beta-2 microglobulin median levels was observed between all different groups. Our results suggest the determination of sHLA-G molecules in both maternal blood and amniotic fluid as a promising biomarker of diagnosis of maternal HCMV primary infection and fetal HCMV disease.

Feasibility of predicting the outcome of fetal infection with cytomegalovirus at the time of prenatal diagnosis

BACKGROUND

Congenital cytomegalovirus infection occurs in 0.7% of live births with 15-20% of infected children developing long-term disability including hearing loss and cognitive deficit. Fetal cytomegalovirus infection is established by viral DNA amplification by polymerase chain reaction in amniotic fluid obtained by amniocentesis following maternal seroconversion or after the diagnosis of ultrasound features suggestive of fetal infection. Severe brain ultrasound anomalies are associated with a poor prognosis. The prognosis of an infected fetus showing either no ultrasound features or nonsevere ultrasound anomalies is difficult to establish up until late in the second or third trimester of pregnancy.

OBJECTIVE

We sought to evaluate the prognostic value of fetal ultrasound, amniotic fluid, and fetal blood analysis at the time of prenatal diagnosis of fetal infection.

STUDY DESIGN

We reviewed all cases of fetal cytomegalovirus infection with a sample of amniotic fluid positive for viral DNA and/or fetal blood analyzed in our laboratory from 2008 through 2013. Prenatal ultrasound features along with cytomegalovirus DNA loads in amniotic fluid and in fetal blood and fetal platelet counts were reviewed in relation to gestational age at maternal infection, neonatal examination, and postnatal follow-up or postmortem examination.

RESULTS

In all, 82 fetuses were infected following maternal infection mainly in the first trimester. At the time of prenatal diagnosis at a median of 23 weeks, 19, 22, and 41 fetuses showed severe brain ultrasound abnormalities, nonsevere ultrasound features, and normal ultrasound examination, respectively. Nonsevere ultrasound features, higher DNA load in amniotic fluid, fetal platelet count ≤114,000/mm(3), and DNA load ≥4.93 log10 IU/mL in fetal blood were associated with a symptomatic status at birth in univariate analysis (P < .001, P = .001, and P = .018, respectively). Bivariate analysis combining ultrasound results and either adjusted viral load in amniotic fluid or fetal blood profile showed that these were independent prognostic factors of a symptomatic status at birth. Both fetal blood parameters were better predictors than amniotic fluid viral load. At the time of prenatal diagnosis, the ultrasound negative predictive value for symptoms at birth or at termination of pregnancy was 93%. The combined negative predictive values of ultrasound and viral load in amniotic fluid and that of ultrasound and fetal blood parameters were 95% and 100%, respectively. In fetuses presenting with nonsevere ultrasound features, the positive predictive values of ultrasound alone and in combination with amniotic fluid viral load or with fetal blood parameters were 60%, 78%, and 79%, respectively.

CONCLUSION

Risk assessment of infected fetuses for being symptomatic at birth is possible as early as the time of diagnosis by using a combination of targeted ultrasound examination along with viral load in amniotic fluid and in fetal blood together with platelet count. The advantage of using amniotic fluid is that it is available at prenatal diagnosis. One may wonder if increasing the negative predictive value of the overall assessment of an infected fetus from 95-100% is worth the additional risk of cordocentesis for fetal blood sampling. This can only be an individual decision made by well-informed women and it seems therefore appropriate to use the figures presented here and their confidence intervals for counseling.

Follow-up of infants with congenital cytomegalovirus and normal fetal imaging

OBJECTIVE

To evaluate the outcome of infants with congenital cytomegalovirus (CMV) infection and normal fetal imaging.

DESIGN

Retrospective cohort study.

SETTING

Tertiary paediatric medical centre.

PATIENTS

98 infants born to mothers with primary CMV infection in the first and second trimesters (diagnosed by positive amniotic fluid findings) and normal fetal imaging.

METHODS

Initial evaluation included confirmatory urine culture, complete blood count, liver and kidney function tests, funduscopy, brain ultrasound and hearing test. Follow-up included periodic neurological and developmental evaluation, hearing tests until age 5 and Bayley-III Developmental Scale (in some patients).

MAIN OUTCOME MEASURES

The presence and rate of sequelae of congenital CMV.

RESULTS

52 (53.1%) infants received early antiviral treatment for central nervous system symptoms or signs, mainly lenticulostriatal vasculopathy on postnatal ultrasonography (88.5%). Sensorineural hearing loss was found on first examination in 16 infants (25 ears), of whom 10 also had cranial ultrasound findings; another five with late-onset hearing loss were also treated. The median follow-up time was 32 (12-83) months. Most infants with moderate and severe hearing loss were infected in the first trimester (10 vs 2, p=0.053). At the last assessment, eight children (10 ears) still had hearing loss, including two with bilateral loss who underwent a cochlear implant. The mean Bayley-III score was 102.6±10.3 (range 85-127). All 98 children attended regular educational institutions.

CONCLUSIONS

Congenital CMV infection acquired from primary maternal infection with normal fetal imaging is associated with a high rate of subtle signs and symptoms after birth. Overall, intermediate-term outcome is good with a low rate of sequelae.

Diagnosis and antenatal management of congenital cytomegalovirus infection

Congenital cytomegalovirus (CMV) is the most common viral infection, affecting nearly 40,000 infants each year in the United States. Of seronegative women, 1-4% will acquire a primary infection during pregnancy, and the majority of these women will be asymptomatic. Prior maternal exposure to CMV does not preclude neonatal infection. The purpose of this document is to review diagnosis of primary maternal CMV infection, diagnosis of fetal CMV infection, and whether antenatal therapy is warranted. We recommend the following: (1) that women with a diagnosis of primary CMV infection in pregnancy be advised that the risk of congenital infection is 30-50%, on average, and that the severity of infection varies widely (Best Practice); (2) for women suspected of having primary CMV infection in pregnancy, we recommend that diagnosis should be either by IgG seroconversion or with positive CMV IgM, positive IgG, and low IgG avidity (grade 1B); (3) amniocentesis is the best option as a prenatal diagnostic tool to detect fetal congenital CMV infection, performed >21 weeks of gestation and >6 weeks from maternal infection (grade 1C); (4) we do not recommend routine screening of all pregnant women for evidence of primary CMV infection at this time (grade 1B); and (5) we do not recommend antenatal treatment with ganciclovir or valacyclovir; and we recommend that any antenatal therapy, either with antivirals or CMV hyperimmune globulin, should only be offered as part of a research protocol (Best Practice).

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.

[A 5-year retrospective clinical study of perinatal cytomegalovirus infection]

OBJECTIVE

To investigate the incidence, clinical features, and treatment of perinatal cytomegalovirus (CMV) infection, as well as the factors affecting the therapeutic effect of ganciclovir.

METHODS

The clinical data of 237 infants who were hospitalized and diagnosed with perinatal CMV infection from 2008 to 2012 were retrospectively analyzed.

RESULTS

The clinical features of infants with perinatal CMV infection and the proportion of such infants in all hospitalized infants showed no significant differences across the five years. In most infants, two or more systems were involved, and CMV hepatitis plus CMV pneumonia was most common (43.1%). The results of pathogen detection showed that the percentage of the infants with positive blood CMV-IgM and blood/urine CMV-DNA was 3.8%, while 90.3% of all infants had positive blood CMV-IgM alone and 5.9% had positive blood/urine CMV-DNA alone. A total of 197 infants were treated with ganciclovir, and the cure rate was 88.3%. An abnormal history of pregnancy (OR=6.191, 95% CI: 1.597-24.002) and liver involvement before medication (OR=3.705, 95% CI: 1.537-8.931) were the independent risk factors affecting the therapeutic effect of ganciclovir in infants with perinatal CMV infection.

CONCLUSIONS

The epidemiological characteristics of perinatal CMV infection have remained generally stable for the last 5 years. CMV often involves several organs or systems, especially the liver and lung. Ganciclovir has a significant efficacy in the treatment of perinatal CMV infection, and an abnormal history of pregnancy and liver involvement before medication can increase the risk of ganciclovir resistance in infants with perinatal CMV infection.

Biology and pathogenesis of cytomegalovirus in periodontal disease

Human periodontitis is associated with a wide range of bacteria and viruses and with complex innate and adaptive immune responses. Porphyromonas gingivalis, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, Treponema denticola, cytomegalovirus and other herpesviruses are major suspected pathogens of periodontitis, and a combined herpesvirus–bacterial periodontal infection can potentially explain major clinical features of the disease. Cytomegalovirus infects periodontal macrophages and T‐cells and elicits a release of interleukin‐1β and tumor necrosis factor‐α. These proinflammatory cytokines play an important role in the host defense against the virus, but they also have the potential to induce alveolar bone resorption and loss of periodontal ligament. Gingival fibroblasts infected with cytomegalovirus also exhibit diminished collagen production and release of an increased level of matrix metalloproteinases. This article reviews innate and adaptive immunity to cytomegalovirus and suggests that immune responses towards cytomegalovirus can play roles in controlling, as well as in exacerbating, destructive periodontal disease.

Congenital cytomegalovirus infection in pregnancy: a review of prevalence, clinical features, diagnosis and prevention

Human cytomegalovirus (CMV) is under-recognised, despite being the leading infectious cause of congenital malformation, affecting ~0.3% of Australian live births. Approximately 11% of infants born with congenital CMV infection are symptomatic, resulting in clinical manifestations, including jaundice, hepatosplenomegaly, petechiae, microcephaly, intrauterine growth restriction and death. Congenital CMV infection may cause severe long-term sequelae, including progressive sensorineural hearing loss and developmental delay in 40-58% of symptomatic neonates, and ~14% of initially asymptomatic infected neonates. Up to 50% of maternal CMV infections have nonspecific clinical manifestations, and most remain undetected unless specific serological testing is undertaken. The combination of serology tests for CMV-specific IgM, IgG and IgG avidity provide improved distinction between primary and secondary maternal infections. In pregnancies with confirmed primary maternal CMV infection, amniocentesis with CMV-PCR performed on amniotic fluid, undertaken after 21-22 weeks gestation, may determine whether maternofetal virus transmission has occurred. Ultrasound and, to a lesser extent, magnetic resonance imaging are valuable tools to assess fetal structural and growth abnormalities, although the absence of fetal abnormalities does not exclude fetal damage. Diagnosis of congenital CMV infection at birth or in the first 3 weeks of an infant's life is crucial, as this should prompt interventions for prevention of delayed-onset hearing loss and neurodevelopmental delay in affected infants. Prevention strategies should also target mothers because increased awareness and hygiene measures may reduce maternal infection. Recognition of the importance of CMV in pregnancy and in neonates is increasingly needed, particularly as therapeutic and preventive interventions expand for this serious problem.

Detection of Cytomegalovirus Antibodies Using a Biosensor Based on Imaging Ellipsometry

Background

Cytomegalovirus (CMV) is the most common infectious cause of mental disability in newborns in developed countries. There is an urgent need to establish an early detection and high-throughput screening method for CMV infection using portable detection devices.

Methods

An antibody analysis method is reported for the detection and identification of CMV antibodies in serum using a biosensor based on high spatial resolution imaging ellipsometry (BIE). CMV antigen (CMV-3A) was immobilized on silicon wafers and used to capture CMV antibodies in serum. An antibody against human immunoglobulin G (anti-IgG) was used to confirm the IgG antibody against CMV captured by the CMV-3A.

Results

Our results show that this assay is rapid and specific for the identification of IgG antibody against CMV. Further, patient serum was quantitatively assessed using the standard curve method, and the quantitative results were in agreement with the enzyme-linked immunosorbent assay. The CMV antibody detection sensitivity of BIE reached 0.01 IU/mL.

Conclusions

This novel biosensor may be a valuable diagnostic tool for analysis of IgG antibody against CMV during CMV infection screening.

Metabolomics technology and their application to the study of the viral infection

OBJECTIVE

In the present review article we have summarized the use of the metabolomics approach to study the metabolic modifications occurring in several bio-fluids due to viral infections. The aim is to highlight the ability of metabolomics to find early fingerprints, which are related to the infections.

METHODS

The (1)H-NMR, UHPLC/MS/MS(2), UPLC/ESI-SYNAPT-HDMS, UPLC-Q-TOF-HDMS analyses were used for the determination of several metabolites representative of the viral infections. The data were analyzed by Principal Component Analysis (PCA), Partial Least Square Discriminant Analysis (PLS-DA) and by regression techniques.

RESULTS

The major changes were related to nucleotide, carbohydrates, lipids and amino acid metabolisms.

CONCLUSIONS

The metabolomics approach could be considered a viable option for characterization of the viral infection and for detecting on going differences in the bio-fluids composition.

Dried blood spots PCR assays to screen congenital cytomegalovirus infection: a meta-analysis

The performance of dried blood spots (DBS) polymerase chain reaction (PCR) assays in screening for congenital cytomegalovirus (cCMV) infection varies between different studies. To determine whether the DBS PCR assay has sufficient accuracy to be used as a screening test for cCMV infection, we performed a meta-analysis of 15 studies (n = 26007 neonates) that evaluated the performance of DBS PCR tests in screening for cCMV infection and that met our inclusion criteria. The pooled sensitivity and specificity were 0.844 (95% CI = 0.812–0.872) and 0.999 (95% CI = 0.998–0.999), respectively, and the diagnostic odds ratio was 1362.10 (95%CI = 566.91–3272.60). As sensitivity analysis showed that the results were robust. In conclusion, the performance of DBS PCR assays for testing cCMV was more suitable for retrospective diagnosis than screening.

Reduced frequencies of polyfunctional CMV-specific T cell responses in infants with congenital CMV infection

PURPOSE

CMV infection remains a priority for vaccine development. Vaccination of infants could modify congenital infection and provide lifetime immunity. Properties of CMV-specific T cells associated with control of viral replication in early life have not been fully defined.

METHODS

CMV-specific CD4 and CD8 T cell responses were investigated in infants with congenital CMV infection and compared to adults with primary or chronic infection. PBMC were stimulated with UL83 (pp65) or UL122 (IE-2) peptide pools then stained with antibodies to markers of T cell subset (CD4 or CD8), phenotype (CD45RA, CCR7), or function (MIP1β, CD107, IFNγ, IL2) for flow cytometry analysis.

RESULTS

Detection of CMV pp65-specific CD4 T cells was less common in infants than adults. Responder cells were primarily effector memory (EM, CD45RA-CCR7-) in adults, but mixed memory subsets in infants. Detection of CMV pp65-specific CD8 T cells did not differ between the groups, but infants had lower frequencies of total responding cells and of MIP1β- or CD107-expressing cells. Responder cells were EM or effector memory RA (CD45RA + CCR7-) in all groups. Polyfunctional T cells were less commonly detected in infants than adults. Responses to IE-2 were detected in adults but not infants. All infants had detectable circulating CMV DNA at initial study (versus 60 % of adults with primary infection) despite longer duration of CMV infection.

CONCLUSIONS

Reduced frequencies and altered functional profile of CMV-specific CD4 and CD8 T cell responses were detected in infants compared to adults, and were associated with persistent CMV DNA in peripheral blood.

Rapid detection of active human cytomegalovirus infection in pregnancy using loop-mediated isothermal amplification

Understanding the association between congenital human cytomegalovirus (HCMV) infection and active maternal HCMV infection during pregnancy is important for maternal and neonatal healthcare. In the present study, a loop-mediated isothermal amplification (LAMP) method was established for the detection of CMV DNA from whole blood or amniotic fluid samples, using reverse transcription-quantitative polymerase chain reaction. The results of the present study demonstrated that the CMV LAMP assay detection was specific for CMV DNA, whereas it did not detect viral DNA from herpes simplex type 1 (HSV-1), HSV-2, varicella zoster virus, HSV-6 or HSV-7. Sensitivity determination using serially-diluted CMV glycoprotein B-containing plasmids, demonstrated that >10 copies per tube were detectable using the CMV LAMP method. Furthermore, the detection results, using the LAMP method for 336 whole blood samples, demonstrated that at a threshold of 10(1)-10(4) copies per tube, the sensitivity of this method was 86.96-100%, the specificity was 97.24-100%, the positive predictive value was 76.92-100% and the negative predictive value was 99.05-100%. The results for 11 amniotic fluid samples from pregnant women with whole blood CMV-positive and 15 control amniotic fluid samples, indicated that the CMV LAMP assay was sensitive and specific for CMV detection. In conclusion, in the present study, a CMV LAMP method was developed, which was shown to be sensitive, specific and efficient in the detection of HCMV infection. Furthermore, CMV LAMP is capable of detecting active CMV infection in pregnant women. Therefore, the current study provides novel insights into diagnostic approaches for active CMV infection in pregnant women.

Perinatal cytomegalovirus and varicella zoster virus infections: epidemiology, prevention, and treatment

Mother-to-child transmission of cytomegalovirus (CMV) and varicella zoster virus (VZV) can lead to severe birth defects and neurologic impairment of infants. Congenital CMV complicates up to 1% of all pregnancies globally. Although antiviral treatment of infants congenitally infected with CMV can ameliorate the CMV-associated hearing loss and developmental delay, interventions to prevent congenital CMV infection and the associated neurologic impairments are still being evaluated. Congenital VZV infection is rare. Active and passive immunization strategies to prevent perinatal CMV infection with similar efficacy to those established to prevent perinatal VZV infections are critically needed in pediatric health.

[The role of virological tests in the diagnosis of cytomegalovirus infection in pregnant women]

INTRODUCTION

The most harmful and most frequent foetal agent is cytomegalovirus. The progress in diagnostic tools and therapeutic opportunities opened new perspectives in the diagnosis and management of foetal cytomegalovirus infection.

AIM

Evaluation of cytomegalovirus virological test results performed during pregnancy between 2007 and 2012.

METHOD

Clinical and virology data were retrospectively analysed.

RESULTS

64.5% of the 956 tested women were serologically protected and 33.3% were susceptible to cytomegalovirus. Recent infection was confirmed in 10 pregnant women, while the infection could not be confirmed or excluded in 3 pregnant women. Six pregnant women were asymptomatic, 5 had typical disease, and 2 had abnormal fetal ultrasound. One fetus aborted, congenital infection was confirmed in 2, and was excluded in one of the four newborns tested.

CONCLUSIONS

The immunity of women to cytomegalovirus reflects high socioeconomic circumstances. Confimatory tests must be done both in women who have cytomegalovirus disease and those who have IgM positive result detected by enzyme (linked) immunoassay. Screening must be done prior to pregnancy. Strict collaboration between professionals of different medical specialties is necessary.

The obstetrician, congenital cytomegalovirus, clinical and diagnostic approaches to the pregnant woman

There is low awareness of congenital cytomegalovirus (CMV) in Australia. Routine pregnancy serological screening for CMV is not recommended, but all pregnant women should be given advice about CMV prevention. Obstetricians may be asked to see a pregnant woman when serology suggests CMV infection or when features of fetal infection are present on ultrasound. If maternal CMV infection is confirmed, the timing of infection (pre-pregnancy or gestation of pregnancy), must be determined to predict the fetal risks. In addition, it is important to establish whether maternal infection is primary or reactivation. If there is fetal infection, ultrasound can be used to attempt to establish whether the fetus may have been affected. Serial serology, CMV IgG avidity, maternal viraemia (using serum PCR), amniotic fluid CMV PCR, serial fetal ultrasounds, and possibly fetal MRI (magnetic resonance imaging) are investigations that may be useful to predict neonatal outcomes. Timely and accurate counselling is important to optimise maternal and neonatal management.

New diagnostics and methods of assessing pregnant women at risk of cytomegalovirus

Human cytomegalovirus (CMV) infection can occur in pregnant women by primary infection or by non-primary infection, namely by either reactivation of the latent virus or reinfection with a different strain1. In all cases the mother can transmit the virus to the fetus through the placenta2,3. In the diagnosis of primary CMV infection, the gold standard is maternal seroconversion to CMV-specific antibodies. Currently, women are not routinely screened for CMV before conception or during pregnancy, thus CMV seroconversion is infrequently documented1. Lastly, serological diagnosis of non-primary CMV infection is very difficult and very often unreliable since no optimal diagnostic methods are currently available. Today, the fetal compartment can be only studied by amniocentesis and ultrasound examination for the diagnosis and prognosis of CMV infection and generally, invasive diagnostic protocol can be only suggested to pregnant women with evidence of primary CMV infection acquired early in gestation and in case of abnormal findings suggestive of congenital infection1. Therefore, a correct maternal diagnosis makes so that invasive prenatal diagnosis is only offered in selected cases. This report points out how a CMV-screening program combined with an advanced diagnostic protocol performed on pregnant women could identify those at high risk of transmitting the virus to their fetus. Furthermore, we evaluated the possible role of soluble HLA-G (sHLA-G) molecules detected in maternal and fetal samples in order to more accurately assess a greater risk of CMV-transmission and fetal/neonatal injury.

Seroprevalence of cytomegalovirus among children 1 to 5 years of age in the United States from the National Health and Nutrition Examination Survey of 2011 to 2012

Cytomegalovirus (CMV) seroprevalence among U.S. children 1 to 5 years old was assessed in the National Health and Nutrition Examination Survey of 2011 to 2012. The overall seroprevalence (95% confidence interval) of IgG was 20.7% (14.4 to 28.2%), that of IgM was 1.1% (0.4 to 2.4%), and that of low IgG avidity was 3.6% (1.7 to 6.6%), corresponding to a 17.3% (10.1 to 26.7%) prevalence of recent infection among IgG-positive children.

UNIVERSAL CYTOMEGALOVIRUS SCREENING: TIME FOR REAPPRAISAL?

Congenital cytomegalovirus (CMV) infection is now the commonest infective cause of neurological handicap. Arguably, there is no other single contributor to developmental disability where a greater opportunity, and imperative, exists to improve outcomes than CMV. CMV is the most common intrauterine infection and congenital CMV is the leading non-inherited cause of sensorineural deafness. The public health impact of CMV is significant: the overall birth prevalence of congenital CMV is estimated at 0.64%, with 11% of live born infants displaying symptoms.

Role of cytomegalovirus (CMV) IgG avidity testing in diagnosing primary CMV infection during pregnancy

The risk of intrauterine transmission of cytomegalovirus (CMV) during pregnancy is much greater for women who contract primary CMV infection after conception than for women with evidence of infection (circulating CMV antibodies) before conception. Thus, laboratory tests that aid in the identification of recent primary CMV infection are important tools for managing the care of pregnant women suspected of having been exposed to CMV. CMV IgM detection is a sensitive marker of primary CMV infection, but its specificity is poor because CMV IgM is also produced during viral reactivation and persists following primary infection in some individuals. Studies conducted over the last 20 years convincingly demonstrate that measurement of CMV IgG avidity is both a sensitive and a specific method for identifying pregnant women with recent primary CMV infection and thus at increased risk for vertical CMV transmission. IgG avidity is defined as the strength with which IgG binds to antigenic epitopes expressed by a given protein; it matures gradually during the 6 months following primary infection. Low CMV IgG avidity is an accurate indicator of primary infection within the preceding 3 to 4 months, whereas high avidity excludes primary infection within the preceding 3 months. In this minireview, we summarize published data demonstrating the clinical utility of CMV IgG avidity results for estimating time since primary infection in pregnant women, describe commercially available CMV IgG avidity assays, and discuss some of the issues and controversies surrounding CMV IgG avidity testing during pregnancy.

Cytomegalovirus seroprevalence in pregnant women and association with adverse pregnancy/neonatal outcomes in Jiangsu Province, China

Background

In this study, we aimed to determine the provincial population-based seroprevalence in pregnant women and to further explore the association of maternal CMV infection status and adverse pregnancy/neonatal/growth outcomes in Jiangsu, China.

Methods

In this case-control study, the sera from 527 pregnant women with adverse pregnancy/neonatal outcomes and 496 mothers of healthy infants in Jiangsu Province, collected at gestation age of 15–20 weeks, were tested for anti-CMV IgG, IgM and IgG avidity. Adverse pregnancy/neonatal outcomes were identified based on pregnancy/neonatal outcomes.

Results

The overall seroprevalence of anti-CMV IgG was 98.7%, with 99.4% and 98.0% in the case and control groups, respectively (P = 0.039). The prevalence of anti-CMV IgG+/IgM+, was higher in the case group than that in the control group (3.8% vs. 1.6%, P = 0.033). Anti-CMV IgG avidity assay showed that none in the control group were primarily infected, but five (0.9%) in the case group underwent primary infection (P = 0.084); all five infants of these women presented severe adverse neonatal/growth outcomes. Exact logistic regression analysis showed that anti-CMV IgG+/IgM+ was associated with adverse pregnancy/neonatal/growth outcomes (aOR = 2.44, 95% CI 1.01–6.48, P = 0.047). Maternal low education level and prior abnormal pregnancies also were risk factors for adverse pregnancy/neonatal outcomes.

Conclusions

In populations with very high prevalence of latent CMV infection, active maternal CMV infection during pregnancy might be a risk factor for adverse pregnancy/neonatal outcomes.

Clinical features of cerebral palsy in children with symptomatic congenital cytomegalovirus infection

BACKGROUND

Human cytomegalovirus is the most common cause of vertically transmitted viral infection, affecting around 1% of liveborns. Infection is symptomatic in nearly 10% of infected children who are at higher risk of development of severe neurological disorders, including cerebral palsy.

AIMS

To study the clinical profile of children with cerebral palsy caused by symptomatic congenital cytomegalovirus infection in a multicenter study involving six countries from the Surveillance of Cerebral Palsy in Europe (SCPE) Network.

METHODS

Data on 35 children (13 males, 22 females; mean age at last assessment 12y 6mo, age range 14y 6mo, min 4y, max 18y 6mo) on pre/peri/neonatal history and last clinical assessment were collected. Classification of cerebral palsy and associated impairments was performed according to SCPE criteria.

RESULTS

The majority of children had bilateral spastic cerebral palsy, 85.7%, with a confidence interval (CI) [69.7-95.2], and 71.4% [CI 53.7-85.4] were unable to walk (GMFCS levels IV-V) while fine motor function was severely affected in 62.8% [CI 44.9-78.5] (BFMF levels IV and V). Most of the children with severe CP had severe associated impairments. 11.4% of children had severe visual and 42.8% severe hearing impairment, 77.1% [CI 59.9-89.6] suffered from epilepsy, also 77.1% had severe intellectual impairment, and speech was undeveloped in 71.4%. Female:male ratio was 1.69:1 and 80% of children were term born.

CONCLUSIONS

Cerebral palsy following symptomatic congenital cytomegalovirus infection seems to be in most cases a severe condition and associated impairments are overrepresented.

Metabolomics: a new tool for the investigation of metabolic changes induced by cytomegalovirus

To date, cytomegalovirus (CMV) is one of the most studied and characterized virus, however the current knowledge on the effect of the human CMV (HCMV) infection on global metabolism is still poorly understood. Metabolomics is a new approach based on the systematic study of the complete set of low molecular weight compounds, both endogenous and exogenous, found within a cell, tissue, biofluid or organism. The purpose of this review is to provide insight into the use of the metabolomic approach on the study of the impact of HCMV on the human metabolome. The results described in this work suggest that metabolomics could be a new tool for HCMV investigation.

Urine real-time polymerase chain reaction detection for children virus pneumonia with acute human cytomegalovirus infection

BACKGROUND

Human cytomegalovirus (HCMV) is an important pathogen of viral pneumonia in children. The diagnosis of acute HCMV infection is complicated and difficult.

METHODS

Clinical and laboratory data of 6063 hospitalized children with respiratory infection and 509 with respiratory virus infection alone were retrospectively analyzed. Urine and respiratory specimens of 186 hospitalized children with pneumonia were also prospectively collected. Real-time polymerase chain reaction (PCR) and a chemiluminescent assay were used to detect HCMV DNA copy number, the pp65 gene, and HCMV IgM.

RESULTS

The patients with respiratory virus infection alone and those with pulmonary HCMV infection (n = 422) were mostly children aged <6 months old (82.91%, 422/509). The accuracy of urine HCMV DNA (82.32%) was higher than that of HCMV IgM (67.78%), indicating that PCR of urine samples is suitable for determining pediatric acute pulmonary HCMV infection. There was no significant difference in detecting HCMV DNA or the pp65 gene between urinary and respiratory specimens (P > 0.05) in 186 pediatric pneumonia cases. The accuracy of the pp65 gene measured in urine for determining acute pulmonary HCMV infection was the highest (93.01%).

CONCLUSIONS

Our study shows a novel method for investigating acute pulmonary HCMV infection in children by using real-time PCR and non-invasive samples. This study also highlights the superiority and potential use of the pp65 gene as an important target for the diagnosis of acute pulmonary HCMV infection.

Cytomegalovirus infection among infants in California neonatal intensive care units, 2005-2010

AIM

To assess the burden of congenital and perinatal cytomegalovirus (CMV) disease among infants hospitalized in neonatal intensive care units (NICUs).

METHODS

CMV infection was defined as a report of positive CMV viral culture or polymerase chain reaction at any time since birth in an infant hospitalized in a NICU reporting to California Perinatal Quality Care Collaborative during 2005-2010.

RESULTS

One hundred and fifty-six (1.7 per 1000) infants were reported with CMV infection, representing an estimated 5% of the expected number of live births with symptomatic CMV disease. Prevalence was higher among infants with younger gestational ages and lower birth weights. Infants with CMV infection had significantly longer hospital stays and 14 (9%) died.

CONCLUSIONS

Reported prevalence of CMV infection in NICUs represents a fraction of total expected disease burden from CMV in the newborn period, likely resulting from underdiagnosis and milder symptomatic cases that do not require NICU care. More complete ascertainment of infants with congenital CMV infection that would benefit from antiviral treatment may reduce the burden of CMV disease in this population.

Cytomegalovirus infection in immunocompetent wheezy infants: the diagnostic value of CMV PCR in bronchoalveolar lavage fluid

WHAT IS KNOWN AND OBJECTIVE

Cytomegalovirus (CMV) pneumonitis in immunocompetent hosts is uncommon but is being recognized more frequently, particularly when presenting as severe viral pneumonia. The objective of this study was to examine lower respiratory tract CMV infection in immunocompetent wheezy infants, based on polymerase chain reaction (PCR) in bronchoalveolar lavage (BAL) fluid, to compare CMV PCR results in BAL and in blood samples and to evaluate the benefits of antiviral ganciclovir therapy in these patients.

METHODS

Retrospective review of the records of patients referred to our tertiary care hospital between January 2000 and July 2010 who had unexplained persistent wheezing and underwent fibreoptic flexible bronchoscopy (FFB).

RESULTS AND DISCUSSION

Fibreoptic flexible bronchoscopy was applied to 102 infants with persistent wheezing and diffuse interstitial infiltration on radiological investigations; so CMV PCR in BAL fluid was performed. CMV PCR in BAL fluid was positive in 51 patients. Retrospectively, we had access to the files of 25 of these patients. The mean CMV PCR in BAL fluid was 334 840 copies/mL. Only eight patients had CMV PCR positivity in their blood samples (mean: 2026·3 copies/mL). There was not a relationship between BAL and blood CMV PCR values based on Spearman's correlation analysis (r = -0·008). Fourteen patients had severe respiratory symptoms and received ganciclovir therapy. Twelve of them fully recovered.

WHAT IS NEW AND CONCLUSION

Bronchoalveolar lavage fluid CMV PCR was superior to blood CMV PCR in diagnosing lower respiratory tract infections caused by CMV in immunocompetent infants. Ganciclovir therapy may be effective in selected immunocompetent wheezy infants with CMV PCR positivity in BAL fluid.

Performance of a cytomegalovirus IgG enzyme immunoassay kit modified to measure avidity

The measurement of cytomegalovirus (CMV) IgG avidity accurately discriminates recent and past CMV infections. We sought to determine if the Wampole Laboratories CMV IgG enzyme immunoassay (EIA) could be modified to measure avidity. The evaluation panel consisted of 156 serum samples we used in 2002 to validate a laboratory-developed EIA, in which 78 serum samples exhibited low avidity, 7 exhibited intermediate avidity, and 71 exhibited high avidity. The qualitative agreement between the two avidity assays was 94% (147/156); all 9 sera with discordant results exhibited intermediate avidity in one of the assays. The avidity index (AI) values in the two assays showed excellent correlation (r = 0.96, P < 0.0001). The definition of high avidity was verified for the Wampole assay by demonstrating high avidity in 91/93 (98%) recently collected CMV IgG-positive/IgM-negative serum samples. The performance of the Wampole avidity assay in a reference laboratory setting was assessed using 470 consecutive serum samples submitted for CMV IgG avidity testing. Surprisingly, 101 serum samples were negative when screened for CMV IgG using the Wampole kit per the package insert; 98 of these 101 serum samples were tested using a CMV IgG chemiluminescent immunoassay, and only 5 were positive. Of the 369 CMV IgG-positive samples, 6% exhibited low IgG avidity, 6% exhibited intermediate avidity, and 88% exhibited high avidity; CMV IgM detection rates were inversely related to AI levels. These findings show that (i) the Wampole CMV IgG EIA can be modified to measure CMV IgG avidity, (ii) many samples are apparently submitted for avidity testing without knowledge of their CMV IgG status, and (iii) most CMV IgG-positive sera submitted for avidity testing exhibit high avidity.

Potential impact of different cytomegalovirus (CMV) IgM assays on an algorithm requiring IgM reactivity as a criterion for measuring CMV IgG avidity

The measurement of cytomegalovirus (CMV) IgG avidity is a powerful tool for identifying individuals with recent CMV infection. Because such patients are expected to be positive for CMV IgM, several investigators have suggested that CMV IgG-positive sera first be screened for CMV IgM and then only the IgM-reactive sera be tested for avidity. We investigated the impact of different CMV IgM assays on such a reflexing algorithm using a panel of 369 consecutive IgG-positive serum samples submitted for avidity testing. A bead-based immunofluorescent assay (BIFA) identified 105 IgM-positive serum samples, whereas an IgM-capture enzyme immunoassay (EIA) identified 48 IgM-positive serum samples; this marked difference led us to evaluate additional CMV IgM assays. An enzyme-linked immunofluorescent assay (ELFA) and a chemiluminescent immunoassay (CIA) were used to test all sera with discordant BIFA/EIA results, all sera with concordant positive results, and selected sera with concordant negative results. The findings indicated that the ELFA would identify 74 CMV IgM-positive samples and the CIA would identify 64. Of the 23 low-avidity serum samples, 2 were IgM negative by BIFA, 3 by ELFA and CIA, and 4 by EIA; of the 23 intermediate-avidity serum samples, 6 were IgM negative by BIFA, 10 by ELFA, and 15 by EIA and CIA. In both these avidity groups, BIFA IgM-negative sera were also negative by the other 3 assays. These findings demonstrate that an algorithm requiring CMV IgM reactivity as a criterion for CMV IgG avidity testing does not identify all low-avidity sera and thus misses some cases of acute CMV infection.

Systematic review of the birth prevalence of congenital cytomegalovirus infection in developing countries

BACKGROUND

Congenital cytomegalovirus (CMV) infection is the leading infectious cause of congenital hearing loss and neurodevelopmental disability in developed countries. Information on congenital CMV infection in developing countries appears to be lacking.

METHODS

We conducted a systematic literature review to identify studies from developing countries with population-based samples of at least 300 infants that used laboratory methods established as reliable for the diagnosis of congenital CMV infection.

RESULTS

Most studies were excluded due to biased samples or inadequate diagnostic methods; consequently the search identified just 11 studies that were from Africa, Asia, and Latin America. The number of newborns tested ranged from 317 to 12 195. Maternal CMV seroprevalence ranged from 84% to 100%. CMV birth prevalence varied from 0.6% to 6.1%. CMV-associated impairments were not documented in most studies.

CONCLUSIONS

Birth prevalence ranges were higher than for Europe and North America, as expected based on the higher maternal CMV seroprevalence. With very limited data available on sequelae, the disease burden of congenital CMV in developing countries remains largely unknown at this time.

Laboratory diagnosis of viral infection

Since the last Handbook of Clinical Neurology volume on this topic, viral diagnosis has made tremendous strides, moving from the margin to the mainstream of clinical care. For many years, conventional virus isolation was the mainstay of viral diagnosis since it was sensitive and “open-minded.” However, growth in conventional cell culture entails an inherent delay that limits its clinical impact. Although rapid culture and viral antigen methods detect fewer pathogens and are less sensitive than conventional culture, both require less expertise and have greatly reduced time to result. Polymerase chain reaction has ushered in a new era in virology, especially in the diagnosis of neurologic diseases. Molecular amplification methods are rapid, highly sensitive, can be automated, quantitative, and detect viruses not amenable to routine culture. User-friendly, walk-away tests with results in an hour, as well as multiplex tests that can detect 20 viruses in a single reaction, are now a reality. As the variety of test methods and commercial products proliferate, the challenges for clinicians and laboratories are selecting which tests to utilize in which clinical scenarios, and understanding how to interpret the results. The advantages and limitations of each method are discussed in this chapter, with special attention to neurologic disease.

Maternal IgG avidity, IgM and ultrasound abnormalities: combined method to detect congenital cytomegalovirus infection with sequelae

OBJECTIVE

We used maternal immunoglobulin M (IgM), immunoglobulin G (IgG) avidity index (AI) and fetal ultrasonography (US) to effectively detect a congenital cytomegalovirus-infected fetus that would suffer neurological sequelae after birth.

STUDY DESIGN

The detecting method was prospectively adapted to 1163 unselected pregnant women. IgM, IgG and IgG-AI were measured at the first prenatal examination (10.8±2.2 weeks of gestation). Advanced US was performed for the IgM-positive women at our center. The urine of 1163 neonates was examined via PCR. All infected neonates were followed for neurological development.

RESULT

Most women (83.3%) were seropositive. Among them, 40 (4.1%) were IgM positive. Nine of forty (22.5%) had low AI, of which one showed abnormal US and suffered severe sequelae. The remaining eight had a normal US; however, one infant had hearing impairment. There were another three infected infants with normal development. Their mothers' serological results were: IgM positive with high AI (n=1); IgG positive; IgM negative with high AI (n=1); and both IgG and IgM negative (n=1).

CONCLUSION

This method enabled us to detect infected fetuses having severe sequelae. However, the problem remains of detecting infected fetuses that only have a hearing impairment.

[Usefulness of a real-time quantitative polymerase-chain reaction (PCR) assay for the diagnosis of congenital and postnatal cytomegalovirus infection]

INTRODUCTION

Cytomegalovirus (CMV) is the main virus causing congenital and postnatal infections in the pediatric population. The aim of this study is to evaluate the usefulness of a quantitative real-time PCR in the diagnosis of these infections using urine as a single sample.

PATIENTS AND METHODS

We studied all the urine samples of newborns (< 7 days) with suspected congenital infection, and urine of patients with suspected postnatal infection (urine negative at birth). Urines were simultaneously studied by cell culture, qualitative PCR (PCRc), and quantitative real-time PCR (PCRq).

RESULTS

We analyzed 332 urine samples (270 to rule out congenital infection and 62 postnatal infections). Of the first, 22 were positive in the PCRq, 19 in the PCRc, and 17 in the culture. PCRq had a sensitivity of 100%, on comparing the culture with the rest of the techniques. Using the PCRq as a reference method, culture had a sensitivity of 77.2%, and PCRc 86.3%. In cases of postnatal infection, PCRq detected 16 positive urines, the PCRq 12, and the cell culture 10. The urines showed viral loads ranging from 2,178 to 116,641 copies/ml.

CONCLUSIONS

The genomic amplification technique PCRq in real time was more sensitive than the other techniques evaluated. This technique should be considered as a reference (gold standard), leaving the cell culture as a second diagnostic level. The low cost and the automation of PCRq would enable the screening for CMV infection in large neonatal and postnatal populations.

Risk factors for poor outcome in congenital cytomegalovirus infection and neonatal herpes on the basis of a nationwide survey in Japan

BACKGROUND

Congenital cytomegalovirus (CMV) infection and neonatal herpes are major mother-to-child infections, and analyses of the important clinical issues, including risk factors for prognosis, are essential.

METHODS

A secondary survey of congenital CMV infection and neonatal herpes was performed using questionnaires for cases reported in the primary survey between 2006 and 2008.

RESULTS

Univariate analysis of 71 cases of congenital CMV infection showed that intrauterine growth restriction (IUGR) or other specific findings on fetal ultrasonography (US), microcephaly, intracranial calcification, disseminated intravascular coagulation, abnormal findings on computed tomography, and the use of i.v. gammaglobulin were all significantly correlated with poor outcome (death or severe sequelae). Multivariate analysis showed that only IUGR was significantly associated with poor outcome. Hearing impairment is one of the major abnormalities associated with congenital CMV infection. Automatic auditory brainstem response (automatic ABR) appeared to be useful for detection of hearing impairment in comparison with conventional ABR. Moreover, univariate analysis showed that specific fetal US or abnormal magnetic resonance imaging findings were correlated with sensorineural hearing loss. In 24 cases of neonatal herpes, fever and seizure were correlated with poor outcome on univariate analysis. All patients received acyclovir treatment, although substantial numbers of patients in severe clinical categories (disseminated or central nervous system diseases) received a low dose of acyclovir (<60 mg/kg per day).

CONCLUSIONS

This secondary survey has identified the risk factors associated with outcome and important issues in diagnosis and treatment of two mother-to-child infections: congenital CMV and neonatal herpes, in Japan.

Diagnosis of congenital cytomegalovirus infection in high risk neonates

Objectives

This study aimed to compare polymerase chain reaction (PCR) and IgM detection using enzyme linked immune-sorbent assay (ELISA) in diagnosis of congenital cytomegalovirus (CMV) infection.

Methods

This study was conducted from May 2009 to December 2010. Urine and blood samples were collected from 94 neonates with suspected congenital CMV infection. Serum and part of urine samples were stored at −20°C freezer, until the serologic and PCR tests were achieved. A 94 fresh urine samples were processed for cell culture. Nineteen (20.2%) out of 94 urine samples were proven positive for CMV infection by viral culture. For comparing PCR and IgM ELISA we used tissue culture technique as a reference, the 19 positive samples on culture (CMV group) and 20 negative samples (control group) were included in the comparison. Some characteristics of CMV and control groups were compared including sex, age, birth weight, gestational age < 37 and small for gestational age. Clinical and laboratory abnormalities were also compared in both groups.

Results

This study showed that the sensitivity and specificity of PCR in relation to viral culture were 100% and 100% respectively, there was excellent agreement between both tests (Kappa coefficient was 1 and P=0.000). On the other hand, the sensitivity of IgM CMV ELISA in relation to viral culture was 63.2% and the specificity was 85%. There was good agreement between both tests (Kappa coefficient was 0.48 and P=0.002). By comparing CMV and control groups, there were high statistically significant differences between both groups as regard the birth weight, gestational age < 37 and small for gestational age items (P= 0.00, 0.03 and 0.01 respectively). There were statistically insignificant differences as regarding the clinical and laboratory abnormalities detected for neonates of both groups. In this study jaundice (63%) and hepato-splenomegaly (42%) were the most common clinical signs in both groups.

Conclusions

PCR is more sensitive and specific technique for detection of congenital CMV infection than CMV IgM ELISA. Being more cost effective, less cumbersome and less time consuming in relation to viral culture, PCR may be used in detection of congenital CMV infection.

Laboratory testing and diagnostic coding for cytomegalovirus among privately insured infants in the United States: a retrospective study using administrative claims data

BACKGROUND

Rates of laboratory testing and diagnostic practices for congenital CMV in the United States are unknown. We determined rates of CMV testing and diagnostic coding for CMV among insured infants in the United States using a national healthcare claims database.

METHODS

We analyzed medical claims from 2011 Truven Health MarketScan® Commercial databases for infants who were ≤30 days of age. We used ICD-9-CM codes to identify infants with CMV and CMV-associated conditions. We computed frequencies of infants with CPT codes for CMV testing.

RESULTS

A total of 368,266 infants met the study criteria. We identified 61 (0.02%) infants with a diagnostic code for CMV. Among the 368,266 infants, 229 (0.1%) infants had a code for CMV-specific testing, of which 43% had codes for CMV polymerase chain reaction (PCR) and/or CMV direct florescent antibody (DFA) testing, 44% for CMV serologic testing alone, and 13% for CMV serology and non-specific PCR and/or culture. Over 80% (187/229) with CMV testing had a code for ≥1 CMV-associated conditions. Although infrequently coded for, CMV testing was more common among infants with a code for a condition possibly associated with CMV than infants without these conditions (0.14% (187/ 136,857) vs. 0.02% (42/231,409)).

CONCLUSIONS

The low rates of CMV testing among infants with symptoms suggestive of congenital CMV infection and the substantial proportion of infants tested with only serologic assays instead of PCR or viral culture suggests gaps in awareness and knowledge of congenital CMV and its diagnosis among healthcare providers. Although claims databases presumably do not capture all diagnosed CMV cases or CMV-specific testing, healthcare claims are a potential source for surveillance and monitoring practices of CMV-specific testing and diagnostic coding for CMV among infants.