Antenatal screening for cytomegalovirus infection: to know the chance, the chance to know

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

First-line noninvasive management of cytomegalovirus primary infection in pregnancy

OBJECTIVES

To introduce a first-line noninvasive antenatal management of maternal cytomegalovirus (CMV) primary infection based on ultrasound (US) and magnetic resonance imaging (MRI). Amniocentesis (AC) is used as a second-line tool in cases of abnormalities compatible with fetal CMV infection on US and/or MRI screening.

METHODS

Between January 2011 and October 2018, pregnant women referred with a CMV primary infection on antibody screening were followed up by monthly US scans and a brain MRI at approximately 32 weeks. In cases with US and/or MRI abnormalities compatible with congenital CMV infection, AC was performed to confirm the diagnosis.

RESULTS

Ninety pregnant women with a primary CMV infection were included (89 singleton and one twin pregnancy). The first-line screening by US and/or MRI was normal for 72 of 91 fetuses (79%). At birth, 19 of these 72 neonates (26%) had a positive urine sample for CMV but were asymptomatic. US and/or MRI abnormalities were identified in 19 fetuses (21%). AC confirmed a fetal CMV infection in 16 fetuses (84%); 12 pregnancies were terminated, and four were continued, with three symptomatic neonates at birth and one poor neurodevelopmental outcome at postnatal follow-up.

CONCLUSIONS

First-line noninvasive management of maternal CMV primary infection based on serial US scans and brain MRI can be offered to identify fetuses with severe symptomatic congenital CMV infection and reduce the number of ACs without compromising the fetal outcome.

Seroprevalence of CMV IgG and IgM in Korean women of childbearing age

BACKGROUND

The aim of this study was to investigate the seroprevalence of cytomegalovirus (CMV) infection using the serologic status of CMV IgG and IgM antibodies in Korean women of childbearing age.

METHODS

We retrospectively reviewed CMV IgG and IgM test results from Korean women aged 15-49 years who underwent testing between January 2009 and December 2019. Seroprevalence of CMV IgG and IgM by year and age was investigated.

RESULTS

The study period was 11 years, and among 6837 samples tested, 95.8% were CMV IgG-positive. The seropositivity in women aged 15- <20 years was significantly lower (77.5%) than older age groups. Among 6837 total CMV IgG tests, 75.9% (5186) had concurrently measured CMV IgM results among which 2.4% were IgM-positive.

CONCLUSION

Considering the low CMV seropositivity of women younger than 20 years, they may need prenatal education for CMV infection.

Advocating for cytomegalovirus maternal serologic screening in the first trimester of pregnancy: if you do not know where you are going, you will wind up somewhere else

Congenital cytomegalovirus infection is an important health problem for the individual and the community. Although it could derive from both primary and nonprimary maternal infection, the prospective risk of congenital infection in seronegative pregnant women is 4 times than that of immune women. Maternal serology is the only reliable screening tool in pregnancy that would identify up to 50% of all congenital cytomegalovirus infections, by yielding positive immunoglobulin M and immunoglobulin G and low immunoglobulin G avidity in approximately 0.5% of the population at 11 to 14 weeks. The exceptionally high risk for young parous seronegative women planning a second pregnancy makes a compelling case for offering serologic screening as soon as pregnancy is planned or diagnosed and by the end of the first trimester. The 11- to 14-week consultation has become an unmissable one worldwide and would represent the most practical compromise if only 1 sample can be taken. Valaciclovir that can be safely used in the early fetal period decreases vertical transmission by 70% and should be implemented as early as possible after maternal infection. Facilities for diagnosis and treatment are available in high- and middle-income countries through laboratory and fetal medicine networks. Amniocentesis with amplification of the viral DNA by polymerase chain reaction in the amniotic fluid is a reliable diagnostic test but chorionic villi sampled by chorionic villus sampling could achieve the same performance 2 months earlier. Fetal imaging of a known infected fetus yields a negative predictive value on symptoms at birth and congenital handicap of between 95% and 99%, and prenatal treatment of infected fetuses decreases the occurrence of symptoms at birth and at 2 years of age.

An observational study to assess Italian obstetrics providers' knowledge about preventive practices and diagnosis of congenital cytomegalovirus

OBJECTIVES

Congenital cytomegalovirus (cCMV) infection can be easily prevented by hygienic measures. Up to date the majority of the studies in literature highlighted a reduction in cCMV antenatal counseling and its prevention. Our purpose was to evaluate obstetrics providers' knowledge about cCMV infection, management and the behavioral practices to avoid it.

METHODS

This is a cross-sectional survey carried out in Umberto I Hospital, "Sapienza" University of Rome between November 2019 and January 2020. We recruited 148 specialists and residents in Obstetrics and Gynecology through online anonymous multiple-choice 13-questions, 10 min-survey comparing responses between the two groups.

RESULTS

A total of 94.6% of all participants said they always prescribe cytomegalovirus (CMV) serum screening: 73.6% of them regularly counsel about preventive practices, with specialists recording higher percentages (85.4 vs. 65.1%, p<0.005). We identified a good knowledge about the diagnostic pathway, but only 58.1% of our population knows the correct time of late amniocentesis. 12.2% of providers do not consider magnetic resonance (MRI) as a complementary exam.

CONCLUSIONS

Prevention of maternal seroconversion is crucial: even if our data show an acceptable knowledge about antenatal counseling, we encourage clinicians to firmly inform and educate women about behavioral measures.