Prenatal diagnosis of fetal cytomegalovirus infection

Blood parameters in fetuses infected with cytomegalovirus according to the severity of brain damage and trimester of pregnancy at cordocentesis

BACKGROUND AND OBJECTIVE

Cytomegalovirus (CMV) remains a major cause of congenital infection and disease. During pregnancy, symptomatic cases can be detected through ultrasound (US) features, nevertheless, prognostic assessment is difficult. The aim of this study was to assess the predictive value of specific blood parameters in CMV infected fetuses.

STUDY DESIGN

Twenty-eight CMV-infected fetuses in which a cordocentesis had been performed were included. Fetuses were considered severely or mildly affected according to prenatal US/MRI brain damage. Fetal blood parameters were assessed for the prediction of severe brain abnormalities, and compared according to the trimester of pregnancy. Logistic regression and receiver operating curve analysis were performed.

RESULTS

Thrombocytopenia (≤100,000/mm³; p:0.03) and high levels of gamma-glutamyl transpeptidase (GGT) (≥151 IU/L; p:0.02) signaled severity. For the prediction of brain damage, GGT levels ≥ 183 UI/l achieved 71% sensitivity, 83% specificity (AUC: 0.78), and OR of 2.05 (95% CI: 1.22-3.43) per 100 IU/l increase, adjusted for gestational age. However, thrombocytopenia (91% vs 50%; p: 0.04), β₂ microglobulin >10.4 mg/l (60% vs 0% p: 0.03), CMV-DNA >50,000 copies/ml (80% vs 25%; p: 0.02), and positive IgM (70% vs 17%; p: 0.04) were observed significantly more often in severely damaged fetuses sampled ≤28 weeks than thereafter.

CONCLUSION

In CMV infected fetuses, thrombocytopenia and high levels of GGT are associated with severe US/MRI brain abnormalities. Nevertheless, among severely affected fetuses, blood parameters, with exception of GGT, change according to gestational age. Fetal blood could be less predictive of brain damage in the third trimester.

Ultrasound Findings Associated With Antepartum Viral Infection

This article reviews the sonographic manifestations of fetal infection and the role of ultrasound in the evaluation of the fetus at risk for congenital infection. Several ultrasound findings have been associated with in utero fetal infections. For the patient with a known or suspected fetal infection, sonographic identification of characteristic abnormalities can provide useful information for counseling and perinatal management. Demonstration of such findings in the low-risk patient may serve to identify the fetus with a previously unsuspected infection. The clinician should understand the limitations of ultrasound in the prenatal diagnosis of congenital infection and discuss them with the patient.

Prenatal diagnosis of congenital cytomegalovirus infection in 115 cases: a 5 years' single center experience

OBJECTIVE

The objective of this study is to investigate the diagnostic value of invasive prenatal diagnosis (PD) of congenital cytomegalovirus (CMV) infection from amniotic fluid (AF) and fetal blood (FB).

METHODS

A retrospective study was conducted on 115 pregnancies with CMV primary infection. A total of 111 AF and 106 FB samples were investigated for various virological and non-virological markers. Detailed ultrasound examinations were performed at time of PD.

RESULTS

Overall sensitivity of CMV PCR in FB (75.6%; 95%CI 60-87) and AF (72.7%; 95%CI 57-85) was comparable. In women with amniocentesis >8 weeks between seroconversion and PD, we did not observe significant differences between amniocentesis performed ≥17 + 0 (sensitivity 90.9%; 95%CI 71-99) and ≥20 + 0 gestational weeks (sensitivity 90.0%; 95%CI 68-99). Virological markers in FB were higher in symptomatic compared with asymptomatic fetuses (p < 0.05). No significant differences were observed for non-virological markers. However, platelet counts <120 × 10e9/L and beta-2 microglobulin values >14 mg/L were more frequently found in fetuses with severe ultrasound abnormalities compared with fetuses with no or mild abnormalities (p < 0.001).

CONCLUSION

Optimal timing of amniocentesis in women with primary infection in early gestation should be reevaluated in a prospective study. Analysis of FB markers may be beneficial in the individual management of pregnant women with confirmed congenital CMV infection. © 2017 John Wiley & Sons, Ltd.

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.

The prognostic value of ultrasound abnormalities and biological parameters in blood of fetuses infected with cytomegalovirus

OBJECTIVE

To evaluate the prognostic value of ultrasound abnormalities and of selected biological parameters in blood of fetuses infected with cytomegalovirus (CMV).

DESIGN

Retrospective observational study.

SETTING

Two fetal medicine units in Paris, France.

POPULATION

All fetuses infected with CMV referred between 1998 and 2006.

METHODS

We retrospectively analysed data collected prospectively in 73 fetuses infected by CMV with a positive CMV polymerase chain reaction in amniotic fluid. Fetal blood sampling (FBS) was performed for evaluation of platelet count, plasma levels of aminotransferases and gamma-glutamyl transpeptidases (GGT), presence of viraemia and specific fetal immunoglobulin M. Targeted ultrasound examination was performed every fortnight. Ultrasound findings were categorised into normal examination and any ultrasound abnormality, which was further grouped as ultrasound abnormality of the fetal brain and noncerebral ultrasound abnormality.

MAIN OUTCOME MEASURES

A combination of histological findings after termination of pregnancy and evidence of cytomegalic inclusion disease at birth when pregnancies were continued. Clinical symptoms at birth or histological lesions attributable to CMV were considered as poor outcome. Statistical analysis was conducted to determine the value of each parameter to predict outcome. Logistic regression was used to build up a multivariate model combining the relevant parameters.

RESULTS

In univariate analysis, only thrombocytopenia and the presence of any ultrasound abnormality were associated with a poor outcome (P < 10(-4) for both abnormalities). In the multivariate analysis, both thrombocytopenia and the presence of ultrasound abnormalities remained significant independent predictors of a poor outcome. Based on univariate logistic regression, odds ratio for a poor outcome were 1.24, 7.2, 22.5 and 25.5 for each 10,000/mm(3) decrease in platelet count, the presence of noncerebral, any ultrasound and cerebral ultrasound abnormalities, respectively.

CONCLUSIONS

The prognosis of CMV-infected fetuses relies independently on both targeted ultrasound examination and fetal platelet count. FBS for platelet count may therefore justify FBS in infected fetuses even in the absence of ultrasound. features of brain involvement.

Nonhuman primate models of intrauterine cytomegalovirus infection

Congenital human cytomegalovirus (HCMV) infection has long been recognized as a threat to the developing fetus, even though studies have shown that only a subset of congenital infections results in clinical signs of disease. Among the estimated 8000 children who develop sequelae from congenital CMV infection each year in the United States alone, most suffer permanent developmental defects within the central nervous system. Because there is currently no approved vaccine for HCMV, and anti-HCMV drugs are not administered to gravid women with congenital infection because of potential toxicity to the fetus, there is a clear clinical need for effective strategies that minimize infection in the mother, transplacental transmission of the virus, and/or fetal disease. Animal models provide a method to understand the mechanisms of HCMV persistence and pathogenesis, and allow for testing of novel strategies that limit prenatal infection and disease. The rhesus macaque model is especially well suited for these tasks because monkeys and humans share strong developmental, immunological, anatomical, and biochemical similarities due to their close phylogenetic relationship. This nonhuman primate model provides an invaluable system to accelerate the clinical development of promising new therapies for the treatment of human disease. This review addresses salient findings with the macaque model as they relate to HCMV infection and potential avenues of discovery, including studies of intrauterine CMV infection. The complexity of the natural history of HCMV is discussed, along with the ethical and logistical issues associated with studies during pregnancy, the recent contributions of animal research in this field of study, and future prospects for increasing our understanding of immunity against HCMV disease.

Human herpes viruses in pregnancy: cytomegalovirus, Epstein-Barr virus, and varicella zoster virus

Viruses of the human herpesvirus family can have profound effects on pregnancy. Primary maternal infection with cytomegalovirus (CMV) and varicella during pregnancy has been associated with fetal abnormalities and neonatal disease. Public awareness of the role of cytomegalovirus in the etiology of developmental disorders and chronic disabilities needs to increase. With time, we may see new interventions for treatment of infected pregnant women and prevention of long-term effects. Attention must be focused on development of a safe and effective vaccine. With the introduction of an efficacious varicella vaccine, the rate of varicella in pregnancy is expected to decrease dramatically. Physicians caring for women have the opportunity to prevent the complications of varicella by identifying and vaccinating susceptible women.

Requirements for diagnosis of prenatal cytomegalovirus infection by amniotic fluid culture

BACKGROUND

Amniotic fluid culture is considered to be the best method for the detection of antenatal cytomegalovirus (CMV) infection and prediction of congenital CMV infection. Recently, however, some false-negative results have been reported.

OBJECTIVES

Prediction of congenital CMV infection by amniotic fluid culture with emphasis on false-negative results.

STUDY DESIGN

Retrospective study of 42 pregnant women with primary CMV infection. First, estimation of seroconversion related to the gestational age was established. Afterwards, results of amniotic fluid culture were compared either with CMV isolation from biopsies from aborted fetuses, or with viral culture of newborns' urine.

RESULTS

In 18 cases (43%), amniotic fluid culture gave negative results which coincided with 18 uninfected newborns. In 18 other cases (43%), amniotic fluid culture was positive for CMV: 7 newborns with CMV viruria and 11 terminations of pregnancy with CMV isolated from fetal biopsies. In the remaining 6 cases, amniotic fluid culture gave negative results, whereas the 6 newborns were all infected.

CONCLUSION

Amniotic fluid culture remains an accurate method for the diagnosis of CMV antenatal infection. However, in order to avoid false-negative results, the importance of a correct estimation of the gestational age of seroconversion and of a sufficient interval between primary infection and amniocentesis are stressed.

Routine CMV screening during pregnancy

Cytomegalovirus (CMV) screening during pregnancy has been widely discussed for several years, but still no consensus has been agreed. With a number of live births of 750,000 per year in France, we would expect 7500 infected infants at birth per year (rate of congenital infection of 1%). Among infected infants at birth, the number of severely infected foetuses would be approximately 75, the number of infants with severe sequelae would be 480, 675 approximately would present with hearing loss and the number of asymptomatic infants would be 6270. Five different preventive methods for congenital CMV infection are possible: (1) Routine CMV screening at the beginning of pregnancy for primary prevention. (2) Secondary prevention by antenatal diagnosis of congenital CMV infection complications. (3) Tertiary prevention by serological testing during pregnancy. (4) Tertiary prevention by serological screening at birth. (5) Tertiary prevention: Hearing loss screening at birth. The aims of this review are to define the advantages and disadvantages of these different methods of CMV screening during pregnancy and to determine if the current available information would make systematic testing acceptable.

Prenatal diagnosis of congenital human cytomegalovirus infection in amniotic fluid by nucleic acid sequence-based amplification assay

Nucleic acid sequence-based amplification assays for detection of human cytomegalovirus (HCMV) immediate-early and pp67 mRNA in 65 amniotic fluid samples tested for prenatal diagnosis of congenital HCMV infection showed sensitivity, specificity, and negative and positive predictive values >90%.

Diagnosis and management of human cytomegalovirus infection in the mother, fetus, and newborn infant

Human cytomegalovirus (HCMV) is the leading cause of congenital viral infection and mental retardation. HCMV infection, while causing asymptomatic infections in most immunocompetent subjects, can be transmitted during pregnancy from the mother with primary (and also recurrent) infection to the fetus. Hence, careful diagnosis of primary infection is required in the pregnant woman based on the most sensitive serologic assays (immunoglobulin M [IgM] and IgG avidity assays) and conventional virologic and molecular procedures for virus detection in blood. Maternal prognostic markers of fetal infection are still under investigation. If primary infection is diagnosed in a timely manner, prenatal diagnosis can be offered, including the search for virus and virus components in fetal blood and amniotic fluid, with fetal prognostic markers of HCMV disease still to be defined. However, the final step for definite diagnosis of congenital HCMV infection is detection of virus in the blood or urine in the first 1 to 2 weeks of life. To date, treatment of congenital infection with antiviral drugs is only palliative both prior to and after birth, whereas the only efficacious preventive measure seems to be the development of a safe and immunogenic vaccine, including recombinant, subunit, DNA, and peptide-based vaccines now under investigation. The following controversial issues are discussed in the light of the most recent advances in the field: the actual perception of the problem; universal serologic screening before pregnancy; the impact of correct counseling on decision making by the couple involved; the role of prenatal diagnosis in ascertaining transmission of virus to the fetus; the impact of preconceptional and periconceptional infections on the prevalence of congenital infection; and the prevalence of congenitally infected babies born to mothers who were immune prior to pregnancy compared to the number born to mothers undergoing primary infection during pregnancy.

Diagnosis and management of human cytomegalovirus infection in the mother, fetus, and newborn infant

Human cytomegalovirus (HCMV) is the leading cause of congenital viral infection and mental retardation. HCMV infection, while causing asymptomatic infections in most immunocompetent subjects, can be transmitted during pregnancy from the mother with primary (and also recurrent) infection to the fetus. Hence, careful diagnosis of primary infection is required in the pregnant woman based on the most sensitive serologic assays (immunoglobulin M [IgM] and IgG avidity assays) and conventional virologic and molecular procedures for virus detection in blood. Maternal prognostic markers of fetal infection are still under investigation. If primary infection is diagnosed in a timely manner, prenatal diagnosis can be offered, including the search for virus and virus components in fetal blood and amniotic fluid, with fetal prognostic markers of HCMV disease still to be defined. However, the final step for definite diagnosis of congenital HCMV infection is detection of virus in the blood or urine in the first 1 to 2 weeks of life. To date, treatment of congenital infection with antiviral drugs is only palliative both prior to and after birth, whereas the only efficacious preventive measure seems to be the development of a safe and immunogenic vaccine, including recombinant, subunit, DNA, and peptide-based vaccines now under investigation. The following controversial issues are discussed in the light of the most recent advances in the field: the actual perception of the problem; universal serologic screening before pregnancy; the impact of correct counseling on decision making by the couple involved; the role of prenatal diagnosis in ascertaining transmission of virus to the fetus; the impact of preconceptional and periconceptional infections on the prevalence of congenital infection; and the prevalence of congenitally infected babies born to mothers who were immune prior to pregnancy compared to the number born to mothers undergoing primary infection during pregnancy.

Prenatal diagnosis of congenital cytomegalovirus infection by detection of immunoglobulin M antibodies to the 70-kd heat shock protein in fetal serum

OBJECTIVE

Antibodies to the 70-kd heat shock protein were evaluated as biomarkers for cytomegalovirus infection.

STUDY DESIGN

Fetal sera that was obtained by cordocentesis at 22 to 25 weeks of gestation from 53 mothers with a confirmed primary cytomegalovirus infection and 28 mothers (control group) without cytomegalovirus infection who had been screened for Rh incompatibility, were assayed by enzyme-linked immunosorbent assay for immunoglobulin M and G anti-70-kd heat shock protein antibodies.

RESULTS

Eighteen of 53 fetuses (34.0%) from cytomegalovirus-positive mothers were infected, which was determined by culture or polymerase chain reaction. Anti-70-kd heat shock protein immunoglobulin M was detected in 17 of 18 sera (94.4%) from cytomegalovirus-infected fetuses, in 3 of 35 sera (8.6%) from uninfected fetuses, and in 0 of 28 sera from the control group (P <.0001). The level of antibody reactivity was correlated positively with fetal disease. Anti-70-kd heat shock protein immunoglobulin G was detected in sera from 52 of 53 fetuses (98.1%) from cytomegalovirus-infected mothers.

CONCLUSION

The anti-70-kd heat shock protein immunoglobulin M assay may be of value in the assessment of fetal cytomegalovirus infection in pregnant women with a primary cytomegalovirus infection.

Recurrent cytomegalovirus infection during pregnancy: ultrasonographic diagnosis and fetal outcome

Fetal infection as a consequence of recurrent disease is uncommon. We present a case of recurrent cytomegalovirus infection in the second trimester of pregnancy. Fetal infection was detected through severely abnormal findings on ultrasound examination and verified by detecting cytomegalovirus DNA in the amniotic fluid and cytomegalovirus-specific immunoglobulin M antibodies in the fetal blood and associated pancytopenia. Because of the severity of the infection, a fatal outcome was predicted. A Cesarean section was performed at 33+5 weeks of gestation; the child died shortly after birth.

Real-time PCR quantification of human cytomegalovirus DNA in amniotic fluid samples from mothers with primary infection

A real-time PCR assay was developed to quantify human cytomegalovirus (HCMV) DNA in amniotic fluid (AF) samples collected from 30 pregnant women with primary HCMV infection as detected either from HCMV-immunoglobulin G (IgG) seroconversion or by the presence of HCMV-specific IgG and IgM associated with a low IgG avidity. Clinical information available for each case included ultrasonographic examination and fetal or newborn outcome. HCMV infection of fetuses or newborns was confirmed for the 30 studied cases. AF samples were subdivided into three groups. In group A (n = 13), fetuses presented major ultrasound abnormalities, and pregnancy was terminated. In group B (n = 13), fetuses had normal ultrasound findings, the pregnancy went to term, and the newborns were asymptomatic at birth. In group C (n = 4), fetuses had no or minor ultrasonographic signs, and pregnancy was terminated. The HCMV DNA load values in AF samples were significantly higher in group A (median, 2.8 x 10(5) genome equivalents [GE]/ml) than in group B (median, 8 x 10(3) GE/ml) (P = 0.014). Our findings suggest that HCMV load level in AF samples correlates with fetal clinical outcome but might also be dependent on other factors, such as the gestational age at the time of AF sampling and the time elapsed since maternal infection.

Prenatal diagnosis of congenital cytomegalovirus infection in 189 pregnancies with known outcome

Prenatal diagnosis (PD) of fetal cytomegalovirus (CMV) infection was performed in 242 pregnancies, with known outcome in 189 cases. In 141/189 pregnancies, PD was carried out on account of suspicious maternal CMV serology up to gestational week (WG) 23, and in 48 cases on account of abnormal ultrasonic findings detected between WG 18 and 39. Chorionic villus samples (n = 6), amniotic fluid (AF, n = 176) and/or fetal blood specimens (n = 80) were investigated for detection of virus by cell culture, shell vial assay, PCR and/or CMV-specific IgM antibodies. Of 189 fetuses correctly evaluated by CMV detection either in fetal tissue following therapeutic abortion/stillbirth (n = 24) or in urine of neonates within the first 2 weeks of life (n = 33), 57 were congenitally infected. In women with proven or suspected primary infection, the intrauterine transmission rates were 20.6% (7/34) and 24.4% (10/41), respectively. Of the congenitally infected live-born infants, 57.6% (19/33) had symptoms of varying degree. The overall sensitivity of PD in the serologic and ultrasound risk groups was 89.5% (51/57). A sensitivity of 100% was achieved by combining detection of CMV-DNA and CMV-specific IgM in fetal blood or by combined testing of AF and fetal blood for CMV-DNA or IgM antibodies. There was no instance of intrauterine death following the invasive procedure. The predictive value of PD for fetal infection was 95.7% (132/138) for negative results and 100% (51/51) for positive results. Correct results for congenital CMV infection by testing AF samples can be expected with samples obtained after WG 21 and after a time interval of at least 6 weeks between first diagnosis of maternal infection and PD. In case of negative findings in AF or fetal blood and the absence of ultrasound abnormalities at WG 22-23, fetal infection and neonatal disease could be excluded with high confidence. Positive findings for CMV infection in AF and/or fetal blood in combination with CMV suspicious ultrasound abnormalities predicted a high risk of cytomegalic inclusion disease (CID). Furthermore, detection of specific IgM antibodies in fetal blood was significantly correlated with severe outcome for the fetus or the newborn (p = 0.0224). However, normal ultrasound of infected fetuses at WG 22-23 can neither completely exclude an abnormal ultrasound at a later WG and the birth of a severely damaged child nor the birth of neonates which are afflicted by single manifestations at birth or later and of the kind which are not detectable by currently available ultrasonographic techniques.

Prenatal diagnosis of congenital cytomegalovirus infection

OBJECTIVE

To assess prospectively the diagnostic reliability and prognostic significance of prenatal diagnosis of cytomegalovirus (CMV) infection.

METHODS

One hundred ten pregnant women (four with twin pregnancies) with a risk of congenital CMV infection were investigated. Prenatal diagnosis was carried out by amniocentesis and fetal blood sampling (n = 75) or amniocentesis alone (n = 35). Serial ultrasonographic examinations were performed from time of referral until pregnancy end. All infected neonates were given long-term follow-up. Autopsy was performed in all cases of termination of pregnancy.

RESULTS

Nearly 23% (26 of 114) of fetuses were infected and prenatal diagnosis was positive in 20 cases. Sensitivity of prenatal diagnosis was 77% and specificity 100%. In eight cases, parents requested termination of pregnancy on the basis of abnormal ultrasonographic findings and/or biologic abnormalities in fetal blood. In 12 cases, parents decided to proceed with the pregnancy. In this group, one intrauterine and one neonatal death were observed. In one case, prenatal diagnosis revealed an abnormal cerebral sonography and the infant had bilateral hearing loss at birth. In 15 cases (nine positive and six false-negative prenatal diagnoses), no apparent lesion was present at birth, nor did it develop during the follow-up period (mean 31 months). In 88 (77.2%) of 114 infants, no evidence of vertical transmission was found during the pre- or postnatal period.

CONCLUSION

Prenatal diagnosis provides the optimal means for both diagnosing fetal infection (amniocentesis) and identifying fetuses at risk of severe sequelae (ultrasound examination, fetal blood sampling), thus allowing proper counseling.

Prenatal diagnosis of fetal primary cytomegalovirus infection

OBJECTIVE

To determine the reliability of prenatal diagnosis for congenital cytomegalovirus in women with primary infection.

DESIGN

Retrospective analysis of case records between 1992 and 1997.

SETTING

Fetal medicine unit of a large teaching hospital.

POPULATION

Forty-two pregnant women with primary cytomegalovirus infection.

METHODS

Fetal diagnosis was made by amniocentesis for viral culture and amplification of cytomegalovirus DNA by polymerase chain reaction (n = 37), or by cordocentesis for the detection of cytomegalovirus-specific IgM antibodies (n = 13). All patients had serial ultrasonographic scans in order to detect those fetuses with abnormalities that could be associated with cytomegalovirus infection.

RESULTS

Fourteen pregnancies (33 x 3%) had evidence of vertical transmission. Nine out of 14 (64 x 3%) had positive amniotic fluid culture, while 11 (78 x 6%) had positive polymerase chain reaction results. The combination of both tests allowed antenatal diagnosis in 12 of the 14 infected fetuses (sensitivity 85 x 7%). All women who underwent cordocentesis for the detection of cytomegalovirus-specific IgM antibodies had negative results, but in two cases cytomegalovirus infection was detected by amniotic fluid studies. In five of the infected fetuses there were abnormal ultrasonographic findings. All pregnancies with evidence of vertical transmission were terminated and the remainder proceeded normally to term.

CONCLUSIONS

Our data showed that amniotic fluid studies, preferably polymerase chain reaction amplification of viral DNA, are the best diagnostic tools for the detection of vertical transmission in pregnancies with primary cytomegalovirus infection. For women with positive amniotic fluid studies who elect to continue their pregnancies, cordocentesis and serial ultrasound scans may be useful for assessment of fetal status.

Development and application of a PCR-based method including an internal control for diagnosis of congenital cytomegalovirus infection

Cytomegalovirus (CMV) is the most common cause of congenital infection in the developed world. We have designed and evaluated an assay that includes an internal control for amplification and detection of CMV DNA in amniotic fluid and neonatal urine samples. We present data on the use of this assay in the diagnosis of congenital CMV infection. A total of 145 amniotic and fetal fluid samples were examined by this assay; 83 were from healthy pregnant women and 62 were from women who were being investigated because of concerns over the pregnancy (diagnostic group). CMV DNA was detected in three amniotic fluid samples from the diagnostic group but was not detected in any samples taken from healthy pregnant women. Thirty-nine urine samples were obtained from 19 neonates with suspected congenital infection; CMV DNA was detected in urine from 6 of these patients. The assay provides useful information about CMV infection in the fetus and the neonate; when used in conjunction with other diagnostic tools it will enable mothers and obstetricians to make informed decisions about the management of pregnancies complicated by CMV infection.

Multi-system cytomegalovirus fetopathy by recurrent infection in a pregnant woman with hepatitis B

A pregnant woman with acute hepatitis B virus (HBV) infection had her second pregnancy terminated at 25 weeks' gestation because of fetal ascites and ventriculitis. Meconium peritonitis was also found at autopsy. No HBV DNA but cytomegalovirus (CMV) DNA was detected in the fetal liver and ascitic fluid. Recurrent maternal CMV infection was demonstrated by pre-existing CMV IgG antibodies, high IgG avidity and low IgM levels. After abortion, the patient developed chronic active hepatitis. Nevertheless, having become pregnant again with a new partner, she had an uneventful third pregnancy and gave birth to a healthy boy.

Prenatal diagnosis of human cytomegalovirus by culture and polymerase chain reaction: 98 pregnancies leading to congenital infection

Human cytomegalovirus (HCMV) is the most common cause of viral intra-uterine infection. The experience with prenatal diagnosis remains limited and is based on few reports of small numbers of cases. It is thus difficult to compare the accuracy of the different tests because the groups studied were small and heterogeneous. We describe here our experience on a series of 98 pregnancies leading to HCMV congenital infection, among which 71 have been tested by amniotic fluid (AF) sampling followed by culture and/or polymerase chain reaction (PCR). Independently of the delay between AF sampling and the first HCMV IgM positive result, the mean sensitivity of both culture and PCR was around 70 per cent. The best sensitivity (95.5 per cent) was obtained after a delay > or = 6 weeks in late pregnancy (> or = 23 weeks). The present study demonstrated clearly that the delay between AF puncture and the presumed date of seroconversion is more important for sensitivity than the technique used for the diagnosis (PCR or culture). However, even in the best diagnostic conditions, negative results of HCMV culture or PCR in AF cannot formally exclude intra-uterine infection.

Ultrasound and fetal diagnosis of perinatal infection

Prenatal ultrasound can aid the clinician in evaluation of the patient with a suspected in utero TORCH infection, particularly toxoplasmosis, syphilis, and CMV. Demonstration of characteristic ultrasound findings in the high risk patient has a high predictive value for fetal infection and also may have prognostic significance. The sonologist should understand the limitations of ultrasound, discuss them with the patient, and document the discussion in the medical record. Patients should be counseled that ultrasound is not a sensitive test for fetal infection and that a normal fetal anatomy survey cannot predict a favorable outcome. In the low-risk patient, fetal infection should be considered when multiple organ system anomalies, fetal growth restriction, placental enlargement, or abnormalities of amniotic fluid volume are demonstrated.

Anticytomegalovirus (anti-CMV) immunoglobulin G avidity in identification of pregnant women at risk of transmitting congenital CMV infection

In this work, we show that the determination of the anticytomegalovirus antibody avidity carried out before week 18 of gestation is a helpful tool to identify women for enrollment in prenatal diagnosis. This procedure can identify all pregnant women who will give birth to an infected newborn.

Predictive value of maternal-IgG avidity for congenital human cytomegalovirus infection

BACKGROUND

Human cytomegalovirus (HCMV) is now the most common cause of viral intrauterine infection. Fetal damage is mostly linked to maternal primary infection. It is therefore important to differentiate primary from recurrent or persistent HCMV infection in pregnant females. For this purpose, IgM tests are not reliable enough and the measurement of the IgG avidity appears to be presently the best method.

OBJECTIVE

To evaluate the performance of the measurement of HCMV-IgG avidity by a 8 M urea denaturation assay in predicting congenital infection in the offspring.

STUDY DESIGN

Seventy-eight women were included in this study on the basis of a HCMV IgM positive or equivocal result on a first serum during pregnancy, but without a documented seroconversion history. The IgG avidity was measured and correlated with the outcome of the pregnancy.

RESULTS

In eight cases of HCMV in utero infection the maternal HCMV-IgG avidity index was below 50%. One case of HCMV in utero infection was observed despite a high avidity index during the second trimester of the pregnancy. High or intermediate HCMV-IgG avidity indexes during the first trimester of pregnancy were not associated with a congenital infection.

CONCLUSIONS

Even in the presence of an IgM positive result, an HCMV IgG avidity index above 65% on a serum obtained during the first trimester of pregnancy could reasonably be considered as a good indicator of past HCMV infection. In these conditions invasive prenatal diagnosis is not necessary.

Prenatal diagnosis of congenital cytomegalovirus infection

We report here the results of a study on the prenatal diagnosis of congenital cytomegalovirus (CMV) infection. The study was carried out by both PCR and virus isolation from amniotic fluid (AF) for 82 pregnant women at risk of transmitting CMV for the detection of (i) seroconversion to CMV immunoglobulin G (IgG) positivity during the first trimester of pregnancy, (ii) symptomatic CMV infection in the mother during the first trimester of pregnancy or intrauterine growth retardation detected by ultrasound or abnormal ultrasonographic findings suggestive of fetal infections, and (iii) seropositivity for CMV-specific IgM. For 50 women, fetal blood (FB) was also obtained and tests for antigenemia and PCR were performed. The results indicate that AF is better than FB for the prenatal diagnosis of CMV infection. PCR with AF has a sensitivity (SNS) of 100%, a specificity (SPE) of 83.3%, a positive predictive value (PPV) of 40%, and a negative predictive value (NPV) of 100%; rapid virus isolation with the same material has an SNS of 50%, an SPE of 100%, a PPV of 100%, and an NPV of 94.7%. Fewer than 10% of the women positive for IgM by enzyme immunoassay (EIA) had a congenitally infected fetus or newborn infant. When EIA IgM positivity was confirmed by Western blotting (WB) and the WB profile was considered, the percent transmission detected among women with an "at-risk" profile was higher than that observed among IgM-positive women and was the same as that among women who seroconverted during the first trimester of pregnancy (transmission rates of 29 and 25%, respectively).

Clinical survey of congenital cytomegalovirus infection in Japan

BACKGROUND

The clinical features of congenital cytomegalovirus (CMV) infection in countries with a higher percentage of maternal seropositivity for CMV has rarely been reported. We conducted a national survey for the first time in Japan to investigate the prevalence of congenital CMV infection.

METHODS

Questionnaires were sent in 1994 to pediatricians and obstetricians of 3398 hospitals with either more than 100 beds or a neonatal intensive care unit (NICU). The questionnaire asked for the number of new cases in 1992 and 1993, maternal status of CMV infection, diagnostic methods, clinical manifestations at birth, sequelae and prognosis.

RESULTS

A total of 46 cases of CMV infection were reported for the years 1992 and 1993 by 1448 hospitals; of these 39 were symptomatic. The annual incidence of symptomatic disease was 1.6 cases/100,000 live births. Major clinical manifestations such as low birthweight, hepatosplenomegaly, petechiae and intracranial calcification were noted at birth in 38-50% of symptomatic neonates. Sequelae, such as hearing loss, mental retardation and motor disability developed in 71% of survivors. Thirty-five percent of the 49 infected infants had either died or had severe disability. Several clinical manifestations at birth, including petechiae/thrombocytopenia, were significantly associated with severe sequelae or a poor prognosis.

CONCLUSION

The lower frequency of clinical findings at birth may be attributed to the higher seroprevalence of pregnant women in Japan than in Europe and the United States.

Cytomegalovirus infection

Cytomegalovirus (CMV) infection is the most common perinatal infection and may result in severe injury to the fetus. Forty percent to 50% of infants delivered to mothers with primary CMV will have congenital infections. Of these, 5% to 18% will be overtly symptomatic at birth. The mortality rate in these children is almost 30%; approximately 80% of the survivors have severe neurological morbidity. The majority of congenitally infected infants will be asymptomatic at birth; 10% to 15% of these children subsequently have sequelae such as visual and auditory defects. If recurrent or reactivated CMV infection develops during pregnancy, the risk of serious fetal injury is very low. Similarly, neonatal infection acquired during delivery or from breast feeding also poses minimal risk to the child. Because antimicrobial therapy and immunoprophylaxis for CMV infection are unsatisfactory, pregnant women must be educated about preventive measures.

Perinatal herpesvirus infections. Herpes simplex, varicella, and cytomegalovirus

The herpesvirus infections (herpes simplex, varicella, and cytomegalovirus) create many dilemmas when encountered during pregnancy. This article reviews the epidemiologic diagnosis and management of perinatal herpesvirus infections. A review of possible future trends is also included.

Ultrasound characteristics of in utero infection

In utero infection of the fetus has become recognized as an important cause of fetal and neonatal morbidity and mortality. Since both anatomic and functional abnormalities have been described in the fetus related to various infections, ultrasonography may be a valuable diagnostic tool in this regard. A complete review of the current literature was undertaken to report available information on this topic. Common pathogens or clinical conditions were selected. The identified data were confounded by the way in which each case originally presented for study. Although certain anomalies were frequently associated with individual organisms, their incidence could not be determined, nor were most specific to that infectious agent. Representative ultrasound images are presented for common and unusual cases.

Treatment of murine cytomegalovirus salivary-gland infection by combined therapy with ganciclovir and thymic humoral factor gamma 2

An optimal therapeutic regimen against primary CMV salivary-gland infection has not yet been developed. We used a murine CMV (MCMV) model system to assess the ability of combined thymic humoral factor THF-gamma 2 immunotherapy and ganciclovir (GCV) antiviral chemotherapy to eliminate detectable viral DNA from salivary glands of infected animals. Mice in different experimental groups were inoculated intraperitoneally with MCMV, treated, and then sacrificed either 2 weeks or 3 months later. To amplify and detect MCMV DNA in infected salivary-gland tissue, we developed a sensitive polymerase chain reaction (PCR) using a glycoprotein B gene primer pair that amplifies a 356 bp segment. During the acute phase of the infection, the detection of high titers of infectious virus in the salivary glands correlated with a strong PCR amplification signal. Although active virions could not be recovered from untreated animals 3 months after viral inoculation, the PCR assay detected a latent MCMV genome. Treatment with either GCV alone or THF-gamma 2 alone had little or no effect on the presence of MCMV DNA. By contrast, combined treatment with THF-gamma 2 and GCV significantly reduced the amount of salivary-gland MCMV DNA to below the limit of PCR detection. The results presented here, and experimental data from previous MCMV research in our laboratories, imply that elimination of the virus from the salivary glands could be due in part to THF-gamma 2 restoration of the various MCMV-suppressed, cell mediated immune-responses. Combining THF-gamma 2 immunotherapy and GCV antiviral chemotherapy may be an important step toward an effective therapeutic regimen that has the potential to prevent the establishment of viral latency ensuing from primary MCMV salivary-gland infection.

Fetal serum interferon-alpha suggests viral infection as the aetiology of unexplained lateral cerebral ventriculomegaly

We assayed fetal serum interferon-alpha (IFNA), a cytokine produced by leukocytes as a response to viral infection, in a series of 59 consecutive cases of ventriculomegaly diagnosed in utero and in 89 controls. Results were correlated with other findings including karyotype, maternal-fetal screening for serum antibodies to specific infectious pathogens, viral cultures of amniotic fluid, and neuropathological examination or postnatal follow-up. Fetal serum IFNA assay was negative in the five ventriculomegalies associated with a genetic anomaly and positive in the three cases with documented cytomegalovirus infections. In addition, fetal serum IFNA was detected significantly more often in the cases of ventriculomegaly with unexplained pathogenesis (15/51, 29.4 per cent) than in controls (1/89, 1.1 per cent). Detection of IFNA suggestive of viral infection in fetuses with otherwise unexplained ventriculomegaly underscores the need for more extensive viral screening in such cases.

Evaluation of virological procedures to detect fetal human cytomegalovirus infection: avidity of IgG antibodies, virus detection in amniotic fluid and maternal serum

Human cytomegalovirus (HCMV) is the most common cause of viral intrauterine infection and fetal damage largely due to maternal primary infection. Virological procedures which are able to detect HCMV fetal infection were evaluated. HCMV IgG antibodies were detected in 62.5% of the pregnant women and 1.47% had a primary infection. From March, 1992 to August, 1995, 29 seroconversions were observed, and in 64 other cases. HCMV IgM antibodies were detected in the first serological test. The mean IgG antibody avidity test (AI) was 31% for the 11 seroconversions tested and 74% in 32 cases where IgG and IgM HCMV antibodies were detected in the first serum. In the 29 HCMV seroconversions, 19 amniocentesis were carried out and 12 fetuses (41.4%) were infected in utero. In four amniotic fluids positive in culture and PCR, the fetus or newborns were infected and in one out of the two cordocentesis undertaken, hepatitis, anemia, and thrombocytopenia were noted. In four other cases, investigations seeking HCMV in amniotic fluid were negative whereas infants were infected at birth. Among the 64 cases with positive HCMV IgM and IgG antibodies detected in the first serological test, three fetuses were infected in utero, but no amniotic fluid was available in these cases. Amniotic fluids were studied in 39 cases, and HCMV detection by culture and PCR-hybridization was negative. HCMV DNA was detected in the maternal sera of five out of 21 pairs of seroconversions and in two cases on the first negative serum. The assay was also carried out on 50 of the 64 HCMV IgM positive sera. Two had detectable HCMV DNA.

Infection materno-foetale à cytomégalovirus

Congenital cytomegalovirus infection is frequent. Symptomatic disease at birth is infrequent but very severe. In most cases the infection is totally asymptomatic but neurosensorial damage can occur in 10 % to 15 % of children, hearing loss being the most frequent. Maternal or neonatal screening is the only way to recognise asymptomatic disease. Wether the screening has to be done, and if so when, will be discussed here.

Congenital cytomegalovirus infection: a long-standing problem still seeking a solution

OBJECTIVE

The purpose of this study was to review the accuracy of current tests used for the diagnosis of in utero cytomegalovirus infection and to discuss the potential value of preconceptional and postconceptional screening programs for prevention of congenital infection.

STUDY DESIGN

A computer-assisted search was performed for relevant English language publications between 1987 and 1994. We identified 119 cases of suspected intrauterine cytomegalovirus infection in which either amniotic fluid or fetal blood had been analyzed antenatally.

RESULTS

Congenital cytomegalovirus infection affects 0.5% to 2.5% of all newborns. The rate of transmission to the fetus after primary infection during pregnancy ranges from 15% to 50%. Of the fetuses infected in utero, 10% exhibit congenital cytomegalovirus syndrome. Evaluation of 119 cases of suspected infection has shown that polymerase chain reaction and cultures of amniotic fluid are the most reliable tests for prenatally determining the presence of viral particles. However, efficacy of routine antenatal screening in reducing the rate of fetal disease is limited.

CONCLUSION

It is concluded that at present the accuracy of tests used for the diagnosis of in utero cytomegalovirus infection is undetermined. Serologic screening of all pregnant women is of limited value and at present is not recommended.

The natural history of fetal cytomegalovirus infection as assessed by serial ultrasound and fetal blood sampling: a case report

A patient in whom intrauterine fetal cytomegalovirus (CMV) infection was diagnosed at approximately 25 weeks' gestation is presented. The fetus was evaluated by serial fetal blood samplings and ultrasound examinations. The fetus manifested evidence of severe thrombocytopenia and hepatic inflammation, with recovery over a period of approximately 8 weeks. The initial sonographic findings of marked fetal ascites and cardiomegaly gradually resolved; ventriculomegaly developed during the third trimester. At delivery, the baby was morphologically normal with the exception of mild ventriculomegaly. Cord blood was negative for CMV IgM but urine was culture-positive for CMV. At age 3, the child has a severe but stable unilateral hearing deficit and is otherwise developmentally normal. This case demonstrates the utility of serial ultrasound and fetal blood sampling in the prenatal diagnosis and management of fetal CMV infection.

Accuracy of amniotic fluid testing before 21 weeks' gestation in prenatal diagnosis of congenital cytomegalovirus infection

Cytomegalovirus (CMV) is the most common cause of intrauterine infection. Recent publications show amniocentesis to have an 81-100 per cent sensitivity in antenatal diagnosis after 21 weeks' gestation. Testing before 21 weeks' gestation is less well documented. We performed 36 amniocenteses between 14 and 20 weeks' gestation. The sensitivity was 45 per cent and the specificity 100 per cent. Implications and possible causes of this low sensitivity are discussed.

Prenatal diagnosis of congenital human cytomegalovirus infection

Fifteen fetuses at risk of congenital human cytomegalovirus (HCMV) infection underwent prenatal diagnosis at 16-30 weeks' gestation by a combination of amniocentesis and fetal blood sampling. HCMV was isolated from the amniotic fluid in six patients, but HCMV-specific IgM was detected in only three of them. Two of the nine neonates, who were delivered following a negative prenatal diagnosis, had congenital HCMV infection diagnosed by virus isolation in the urine. The interval from infection to prenatal testing was 3 and 4 weeks in the two false-negative cases and > or = 7 weeks in the true-positive cases. Although timely testing for HCMV infection allows the option of termination of pregnancy, it may be flawed by false-negative results.

Prenatal ultrasonographic diagnosis of fetal cerebral ventriculitis associated with asymptomatic maternal cytomegalovirus infection

Cytomegalovirus is the most common cause of congenital viral infection. In utero infection is usually suspected in patients with growth-retarded fetuses or when maternal illness precipitates serological investigations. A case is presented where routine ultrasound examination at 30 weeks' gestation in an asymptomatic patient demonstrated mild fetal ventriculomegaly. Transvaginal ultrasound enabled the visualization of intraventricular adhesions and small periventricular cysts. The suspected diagnosis of in utero cytomegalovirus infection was confirmed by the presence of IgM antibodies in fetal blood and subsequently by isolation of the virus from the infant's urine. The presence of mild fetal ventriculomegaly should prompt transvaginal brain imaging.

Cytomegalovirus infection in pregnancy

Cytomegalovirus (CMV) infection is of great importance to obstetrician-gynecologists because maternal infection is relatively common and can result in severe injury to the fetus. The greatest risk to the fetus occurs when the mother develops a primary CMV infection in the first trimester. Forty to 50% of infants delivered to mothers with primary CMV infections will have congenital infections. Of these neonates, 5–18% will be overtly symptomatic at birth. Approximately 30% of severely infected infants die, and 80% have severe neurologic morbidity. Eighty-five to 90% of infants will be asymptomatic, and 10–15% of these babies subsequently have sequelae such as visual and auditory defects. If the mother develops a recurrent or reactivated CMV infection during pregnancy, the risk of a severe congenital infection is very low. Perinatal infection, as opposed to congenital infection, may result from exposure to the virus during delivery or lactation and rarely leads to serious sequelae. Antimicrobial therapy and immunotherapy for CMV are, at present, unsatisfactory. Therefore, all patients, pregnant women in particular, must be educated about preventive measures.

Prenatal diagnosis of congenital cytomegalovirus infection: false-negative amniocentesis at 20 weeks' gestation

Cytomegalovirus (CMV) is the most common cause of congenital infection. Recent studies show amniocentesis to be a 100 per cent sensitive and 100 per cent specific predictor of congenital infection, and recommend that it be offered in the at-risk pregnancy. However, these publications have focused on pregnancies at or beyond 22 weeks' gestation. Here, we report a case of maternal CMV hepatitis at 7-8 weeks' gestation, in which culture and polymerase chain reaction testing for CMV in amniotic fluid at 20 weeks' gestation were negative, but the infant had a positive CMV urine culture shortly after delivery. Implications for the prenatal diagnosis of CMV infection are discussed.