Prenatal diagnosis of fetal cytomegalovirus infection after primary or recurrent maternal infection

Hygiene promotion might be better than serological screening to deal with Cytomegalovirus infection during pregnancy: a methodological appraisal and decision analysis

BACKGROUND

Cytomegalovirus infection is the most frequent viral congenital infection, with possible consequences such as deafness, or psychomotor retardation. In 2016, the French High Council of Public Health was mandated to update recommendations regarding prevention of cytomegalovirus infection in pregnant women. We summarize a critical appraisal of knowledge and deterministic decision analysis comparing the current no-screening situation to serological screening during pregnancy, and to hygiene promotion.

METHODS

Screening was defined as systematic serological testing, during the first trimester, with repeated tests as needed, to all pregnant women. Outcomes were: 1) severe sequela: intellectual deficiency with IQ ≤ 50 or hearing impairment < 70 dB or sight impairment (≤ 3/10 at best eye); 2) moderate sequela: any level of intellectual, hearing or sight deficiency; and 3) death or termination of pregnancy. We simulated the one-year course of cytomegalovirus infection in a cohort of 800,000 pregnant women. We developed a deterministic decision model, using best and min-max estimates, extracted from systematic reviews or original studies.

RESULTS

Relevant data were scarce or imprecise. We estimated that 4352 maternal primary infections would result in 1741 foetal infections, and an unknown number of maternal reinfections would result in 1699 foetal infections. There would be 788 cytomegalovirus-related consequences, including 316 foetal deaths or terminations of pregnancy, and 424 moderate and 48 severe sequelae. Screening would result in a 1.66-fold increase of poor outcomes, mostly related to a 2.93-fold increase in deaths and terminations of pregnancy, not compensated by the decrease in severe symptomatic newborns. The promotion of hygiene would result in a 0.75-fold decrease of poor outcomes, related to both a decrease in severe sequelae among symptomatic newborns (RR = 0.75; min-max: 1.00-0.68), and in deaths and terminations of pregnancy (RR = 0.75; min-max: 0.97-0.68).

CONCLUSIONS

Prevention of cytomegalovirus infection during pregnancy should promote hygiene; serological screening should not be recommended.

Hyperimmune globulin in pregnancy for the prevention of congenital cytomegalovirus disease

INTRODUCTION

Cytomegalovirus (CMV) is the most common and serious cause of congenital infections in developed countries since it is capable of infecting the fetus after both primary and recurrent maternal infection, and can be spread for years by infected children. Areas covered: Animal and human pregnancy studies about the prevention of congenital CMV infection and disease by CMV-specific hyperimmune globulin (HIG). Commercial HIG is manufactured from the plasma of selected donors with high anti-CMV antibody avidity and titers. Expert commentary: Currently available experimental and clinical studies and case reports support the possible effectiveness and safety of HIG infusions in pregnancy for the prevention of congenital CMV disease. The knowledge about the potential efficacy of preventive or therapeutic HIG administration should be enlarged by multi-center randomized studies, which may be favored by the implementation of CMV screening. Meanwhile, if ultrasound examinations show signs of fetal injury, or CMV is detected in the amniotic fluid, the patients should be advised about the possible option of HIG therapy.

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.

Cytomegalovirus non-primary infection during pregnancy. Can serology help with diagnosis?

Diagnosis of cytomegalovirus (CMV) primary infection is reliable, but diagnosis of CMV non-primary infection (NPI) is questionable. Our aim is to highlight the difficulties met in diagnosis of CMV NPI. We illustrate that in proven cases of CMV NPI, very different serologic and molecular patterns may be observed and that routine serologic testing may fail to help with diagnosis. These results point out that many data available in literature concerning the prevalence of NPI, materno-fetal transmission rates and consequences of NPI may be wrong. We need to know how frequently they occur, are transmitted and cause fetal damages. Diagnosis of NPI must be improved, along with our understanding of the mechanisms leading to intrauterine CMV transmission and congenital infection in babies born to women with preexisting immunity.

Intrauterine infection with parvovirus B19 and CMV: implications in early and late gestation fetal demise

In utero viral infections have been associated with an adverse pregnancy outcome and may have a causative role in the unexplained fetal death file. Parvovirus B19 and cytomegalovirus are among the most common pathogens implicated in fetal loss cases. Parvovirus B19 has been reported to account for cases of spontaneous abortions, intrauterine fetal death and nonimmune hydrops fetalis, whereas cytomegalovirus accounts for nonimmune hydrops fetalis, intrauterine growth retardation and congenital anomalies. This review aims to summarize the current literature in an attempt to underline the need for routine screening, close follow-up and prevention. A better understanding of the pathogenetic mechanisms of viral infections during the crucial time of organogenesis, along with early detection, may contribute to the reduction in stillbirth rate.

Can measurement of maternal anti-cytomegalovirus immunoglobulin-M antibody levels be used to screen for cytomegalovirus infection in embryos and fetuses?

AIMS

 Our study aims to estimate whether measurement of maternal anti-cytomegalovirus immunoglobulin-M antibody (CMV-IgM) levels are useful as a screening method for achieving early detection of congenital CMV infection.

MATERIAL AND METHODS

  Levels of maternal CMV-IgM were measured by enzyme immunoassay in all (n =2865) pregnant women who visited our hospital in the first trimester during the period from January 2005 to December 2009.

RESULTS

Among them, 21 individuals (0.73%) had a CMV-IgM titer of ≥0.08 and were judged to be CMV-IgM-positive. Informed consent was obtained from all 21 individuals to perform the confirmation test that quantifies the levels of cytomegalovirus DNA (CMV-DNA) in amniotic fluid by real-time polymerase chain reaction. However, only one (0.03%) of the 21 individuals was CMV-DNA-positive (CMV-DNA concentration, 1.0 × 10(4) copies/ml).

CONCLUSION

  In order to detect congenital CMV infection in early pregnancy, it is considered appropriate to use ultrasound for close examination of embryo or fetal symptoms indicative of CMV instead of performing serological screening based on CMV-IgM.

Foscarnet therapy for congenital cytomegalovirus liver fibrosis following prenatal ascites

We report on an infant with multi-system disease including liver fibrosis, right microphthalmia with cataract, interstitial pneumonitis, and hyperechoic lesions in the basal ganglia and in the periventricular and thalamic regions. Prenatal ascites with hepatomegaly concomitantly with detection of cytomegalovirus (CMV) DNA in the amniotic fluid, following recurrent maternal CMV infection, had been shown. Although CMV culture and DNA detection were negative in the urine, the infant was given foscarnet because CMV infection was demonstrated in the liver by DNA detection and immunohistochemical staining. Favorable clinical outcome and absence of CMV in the liver were subsequently shown. Our case suggests that congenital CMV disease following maternal recurrence may not be associated with disseminated infection but only with intracellular infection. The diagnosis should therefore be based on CMV detection in the involved organs. Moreover, this is the first report on the possible efficacy and safety of foscarnet for therapy of immunocompetent infants with congenital CMV disease.

Fetal ascites owing to congenital cytomegalovirus: response to ganciclovir

A term newborn with severe congenital cytomegalovirus (CMV) infection is described. Fetal ascites was detected at 28 weeks gestation, and at birth there was tense ascites. There was intra-uterine growth retardation, microcephaly, chorioretinitis, jaundice, purpura and pneumonitis. Computed tomographic scan of the brain showed ventriculomegaly with periventricular calcifications. Serology was positive for cytomegalovirus-specific immunoglobulin M, and cytomegalovirus DNA was detected in the ascitic fluid and urine by nested polymerase chain reaction. He received 6 weeks of treatment with ganciclovir. Ascites resolved spontaneously and liver function tests became normal. Although there was a good clinical response to ganciclovir therapy without any side-effects, on follow-up the infant had global developmental delay and bilateral sensorineural deafness.

Primary versus nonprimary cytomegalovirus infection during pregnancy, Israel

We examined prospectively the outcome of primary and nonprimary maternal cytomegalovirus (CMV) infection during pregnancy among 88 and 120 women, respectively. The risk for vertical transmission was 1.83× higher for primary infection than for nonprimary infection. Nonetheless, congenital CMV disease was diagnosed in both infection groups at similar rates.

Placental enlargement in women with primary maternal cytomegalovirus infection is associated with fetal and neonatal disease

BACKGROUND

Serological testing for primary maternal cytomegalovirus (CMV) infection during pregnancy is not routine, but ultrasound studies are routine. Therefore, we evaluated placental thickening in women with primary CMV infection during pregnancy.

METHODS

The study included 92 women with primary CMV infection during pregnancy and 73 CMV-seropositive pregnant women without primary CMV infection. Neonatal CMV transmission was determined by CMV culture of urine samples. Thirty-two women were treated with CMV hyperimmune globulin to either prevent or treat intrauterine CMV infection. Maximal placental thickness was measured by longitudinal (nonoblique) scanning with the ultrasound beam perpendicular to the chorial dish. Programmed placental ultrasound evaluations were performed from 16 to 36 weeks of gestation.

RESULTS

At each measurement between 16 and 36 weeks of gestation, women with primary CMV infection who had a fetus or newborn with CMV disease had placentas that were significantly thicker than those of women with primary CMV infection who did not have a diseased fetus or newborn (P<.0001); the latter group, in turn, had placentas that were significantly thicker than those of seropositive control subjects (P<.0001). For both women with and women without diseased fetuses or newborns, receipt of hyperimmune globulin after primary CMV infection was associated with statistically significant reductions in placental thickness (P<.001). Placental vertical thickness values, which are predictive of primary maternal infection, were observed at each measurement from 16 to 36 weeks of gestation, and cutoff values ranged from 22 mm to 35 mm, with the best sensitivity and specificity at 28 and 32 weeks of gestation.

CONCLUSIONS

Primary maternal CMV infection and fetal or neonatal disease are associated with sonographically thickened placentas, which respond to administration of hyperimmune globulin. These observations suggest that many of the manifestations of fetal and neonatal disease are caused by placental insufficiency.

Passive immunization during pregnancy for congenital cytomegalovirus infection

BACKGROUND

Currently, there is no effective intervention for a primary cytomegalovirus (CMV) infection during pregnancy.

METHODS

We studied pregnant women with a primary CMV infection. The therapy group comprised women whose amniotic fluid contained either CMV or CMV DNA and who were offered intravenous CMV hyperimmune globulin at a dose of 200 U per kilogram of maternal weight. A prevention group, consisting of women with a recent primary infection before 21 weeks' gestation or who declined amniocentesis, was offered monthly hyperimmune globulin (100 U per kilogram intravenously).

RESULTS

In the therapy group, 31 women received hyperimmune globulin, only 1 (3 percent) of whom gave birth to an infant with CMV disease (symptomatic at birth and handicapped at two or more years of age), as compared with 7 of 14 women who did not receive hyperimmune globulin (50 percent). Thus, hyperimmune globulin therapy was associated with a significantly lower risk of congenital CMV disease (adjusted odds ratio, 0.02; 95 percent confidence interval, -infinity to 0.15; P<0.001). In the prevention group, 37 women received hyperimmune globulin, 6 (16 percent) of whom had infants with congenital CMV infection, as compared with 19 of 47 women (40 percent) who did not receive hyperimmune globulin. Thus, hyperimmune globulin therapy was associated with a significantly lower risk of congenital CMV infection (adjusted odds ratio, 0.32; 95 percent confidence interval, 0.10 to 0.94; P=0.04). Hyperimmune globulin therapy significantly (P<0.001) increased CMV-specific IgG concentrations and avidity and decreased natural killer cells and HLA-DR+ cells and had no adverse effects.

CONCLUSIONS

Treatment of pregnant women with CMV-specific hyperimmune globulin is safe, and the findings of this nonrandomized study suggest that it may be effective in the treatment and prevention of congenital CMV infection. A controlled trial of this agent may now be appropriate.

[CMV infection: when should medical termination of pregnancy be discussed?]

OBJECTIVES

To determine in which circumstances termination of pregnancy (TOP) could be proposed in case of CMV infection.

PATIENTS AND METHODS

An inquiry was conducted concerning the practice of doctors working in French foetal medicine units in case of CMV infection. The question asked was: "What is your attitude if confronted to a CMV seroconversion at 23 weeks of amenorrhoea with positive PCR at 28 WA, and normal MRI and ultrasound scan at third trimester?"

RESULTS

Thirty-five obstetricians answered. Forty-nine percent do not perform foetal blood sampling (FBS). Among them 1/17 would accept TOP. Fifty-one percent do perform FBS. In this group, 33% would accept TOP in case of negative FBS and 83% if FBS shows foetal infection.

DISCUSSION AND CONCLUSION

Techniques available for diagnosis and prognosis of foetal infections are based on PCR on amniotic fluid, ultrasound, MRI and FBS. To date correlation of those tests with foetal outcome has not been fully validated. TOP could therefore be an option in 2 circumstances: when signs of certain severe foetal disease with positive PCR and ultrasound abnormalities; on statistical arguments: if positive PCR, and normal ultrasound, the risk of handicap is approximately 10%, the severity of the handicap being impossible to predict. In this last hypothesis, it is tempting to use additional arguments such as FBS even if the interpretation of the results of this test has not been scientifically validated. Such cases with positive PCR and normal ultrasound in which inconsistent decisions are made are likely to be more frequent because of routine serologic screening policy.

Hydrops fetalis

Although most NIH fetuses have poor prognosis, it is imperative to attempt to identify the underlying cause to present parents with the best estimate for prognosis and future outcomes. Identification of a disorder with a good prognosis may prevent unnecessary termination of pregnancy and give a chance for therapy. Identification of a disorder with poor prognosis may still provide information that may be unavailable after delivery regarding this and future pregnancies.