Use of serial maternal urine cytomegalovirus PCR to detect primary CMV infection in seronegative pregnant women

Primary, Secondary, and Tertiary Prevention of Congenital Cytomegalovirus Infection

Cytomegalovirus infection is the most common congenital infection, affecting about 1% of births worldwide. Several primary, secondary, and tertiary prevention strategies are already available during the prenatal period to help mitigate the immediate and long-term consequences of this infection. In this review, we aim to present and assess the efficacy of these strategies, including educating pregnant women and women of childbearing age on their knowledge of hygiene measures, development of vaccines, screening for cytomegalovirus infection during pregnancy (systematic versus targeted), prenatal diagnosis and prognostic assessments, and preventive and curative treatments in utero.

Cytomegalovirus Urinary Shedding in HIV-infected Pregnant Women and Congenital Cytomegalovirus Infection

BACKGROUND

Cytomegalovirus (CMV) urinary shedding in pregnant women infected with human immunodeficiency virus (HIV) was evaluated to determine whether it poses an increased risk for congenital CMV infection (cCMV).

METHODS

A subset of mother-infant pairs enrolled in the perinatal NICHD HPTN 040 study (distinguished by no antiretroviral use before labor) was evaluated. Maternal and infant urines were tested by qualitative real-time polymerase chain reaction (RT-PCR) for CMV DNA with quantitative RT-PCR performed on positive specimens.

RESULTS

Urine specimens were available for 260 women with 85.4% from the Americas and 14.6% from South Africa. Twenty-four women (9.2%) had detectable CMV viruria by qualitative PCR. Maternal CMV viruria was not associated with mean CD4 cell counts or HIV viral load but was associated with younger maternal age (P = .02). Overall, 10 of 260 infants (3.8%) had cCMV. Women with detectable peripartum CMV viruria were more likely to have infants with cCMV than those without: 20.8% (5/24) versus 2.1% (5/236), (P = .0001). Women with CMV viruria had significantly higher rates of HIV perinatal transmission (29.2% vs. 8.1%, P = .002). They were 5 times (adjusted odds ratio [aOR] = 5.6, 95% confidence interval [CI] 1.9-16.8) and nearly 30 times (aOR, 29.7; 95% CI, 5.4-164.2) more likely to transmit HIV and CMV to their infants, respectively. Maternal gonorrhea (aOR, 19.5; 95% CI, 2.5-151.3) and higher maternal HIV log10 viral load (OR, 2.8; 95% CI, 1.3-6.3) were also significant risk factors for cCMV.

CONCLUSION

In this cohort of HIV-infected pregnant women not on antiretrovirals, urinary CMV shedding was a significant risk factor for CMV and HIV transmission to infants.

CLINICAL TRIALS REGISTRATION NUMBER

NCT00099359.

Feasibility and acceptability of targeted screening for congenital CMV-related hearing loss

BACKGROUND

Congenital cytomegalovirus (cCMV) is the most common non-genetic cause of sensorineural hearing loss (SNHL) in children. Ganciclovir has been shown to prevent the continued deterioration in hearing of children with symptomatic cCMV, but some children with cCMV-related SNHL are unidentified in the neonatal treatment period. Neonatal cCMV screening provides an opportunity to identify infants with cCMV-related SNHL who might benefit from early treatment.

OBJECTIVES

To assess the feasibility (ability to take samples before 3 weeks of age and clinical assessment by 30 days of age) and acceptability (maternal anxiety) of targeted CMV testing of infants who are 'referred' for further audiological testing after routine newborn hearing screening programme (NHSP).

METHODS

Parents of infants who have 'no clear responses' on routine NHSP before 22 days of life in London and North East England were approached. Salivary and urine samples were tested by CMV PCR. At recruitment and 3 months, the short form Spielberger State-Trait Anxiety Inventory measured maternal anxiety.

RESULTS

411 infants were recruited. 99% (407/411) returned a sample; 98% (404/411) successfully yielded a CMV result, 6 had cCMV, all diagnosed on salivary samples taken <22 days of age (1.5%; 95% CI 0.6% to 3.2%). Only 50% returned urine samples compared with 99% returning salivary samples (p<0.001). Using saliva swabs 98% were successfully screened for CMV within 3 weeks. All positive screening CMV results were known by day 23, and 5/6 infants with cCMV were assessed within 31 days. Anxiety was not increased in mothers of infants screened for cCMV.

CONCLUSIONS

Targeted salivary screening for cCMV within the NHSP is feasible, acceptable and detects infants with cCMV-related SNHL who could benefit from early treatment.

Predictive factors of cytomegalovirus seropositivity among pregnant women in Paris, France

Background

Cytomegalovirus (CMV) is the most frequent cause of congenital infection. The objective of this study was to evaluate predictive factors for CMV seronegativity in a cohort of pregnant women in Paris, France.

Methods

Pregnant women enrolled in a prospective cohort during the 2009 A/H1N1 pandemic were tested for CMV IgG antibodies. Variables collected were age, geographic origin, lifestyle, work characteristics, socioeconomic status, gravidity, parity and number of children at home. A multivariate logistic regression model was used to identify independent predictive factors for CMV seropositivity.

Results

Among the 826 women enrolled, 389 (47.1%) were primiparous, and 552 (67.1%) had Metropolitan France as a geographic origin. Out of these, 355 (i.e. 57.0%, 95% confidence interval (CI): [53.6%–60.4%]) were CMV seropositive: 43.7% (95% CI:[39.5%–47.9%]) in those whose geographic origin was Metropolitan France and 84.1% in those with other origins (95% CI:[79.2%–88.3%]).

Determinants associated with CMV seropositivity in a multivariate logistic regression model were: (i) geographic origin (p<0.001(compared with Metropolitan France, geographic origins of Africa adjusted odds ratio (aOR) 21.2, 95% CI:[9.7–46.5], French overseas departments and territories and other origin, aOR 7.5, 95% CI:[3.9–14.6], and Europe or Asia, aOR 2.2, 95% CI: [1.3–3.7]); and (ii) gravidity (p = 0.019), (compared with gravidity = 1, if gravidity≥3, aOR = 1.5, 95% CI: [1.1–2.2]; if gravidity = 2, aOR = 1.0, 95% CI: [0.7–1.4]). Work characteristics and socioeconomic status were not independently associated with CMV seropositivity.

Conclusions

In this cohort of pregnant women, a geographic origin of Metropolitan France and a low gravidity were predictive factors for CMV low seropositivity. Such women are therefore the likely target population for prevention of CMV infection during pregnancy in France.

Prevalence of cytomegalovirus DNA in cord blood and voided urine obtained from pregnant women at the end of pregnancy

OBJECTIVE

This study was undertaken to determine the prevalence of congenital cytomegalovirus (CMV) infection in pregnant women at the end of pregnancy in Kuwait using cord blood and maternal urine.

SUBJECTS AND METHODS

Urine samples were collected prior to childbirth, and cord blood was collected immediately after delivery from 983 women. Anti-CMV IgG and IgM antibodies were determined using ELISA; CMV DNA was detected using nested PCR, and viral load was calculated using real-time PCR. CMV concentration in samples was categorized as low when the viral load ≤10(3) copies/µl, intermediate when the viral load = 10(3)-10(4) copies/µl, and high when the viral load >10(4) copies/µl. The cord blood serology outcome was compared to cord blood PCR, cord blood viral load, maternal urine PCR and viral load analyses.

RESULTS

Serology showed that of the 983 cord blood samples, 89 (9%) were positive for anti-CMV IgM antibodies; PCR test showed 44 (4.5%) contained CMV DNA, and there was a high viral load in all. Maternal urine PCR showed that 9 (10.11%) women had CMV DNA, and there was a high viral load in 7 (78%). The kappa test for measures of agreement showed a reasonable agreement (0.45) between cord blood PCR and urine PCR.

CONCLUSION

This study showed that CMV infection in the cord blood sera of pregnant women is common in Kuwait and highlights the need for more clinically based studies to follow up newborns with congenital CMV infection.

Effectiveness of interventions to screen and manage infections during pregnancy on reducing stillbirths: a review

BACKGROUND

Infection is a well acknowledged cause of stillbirths and may account for about half of all perinatal deaths today, especially in developing countries. This review presents the impact of interventions targeting various important infections during pregnancy on stillbirth or perinatal mortality.

METHODS

We undertook a systematic review including all relevant literature on interventions dealing with infections during pregnancy for assessment of effects on stillbirths or perinatal mortality. The quality of the evidence was assessed using the adapted Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach by Child Health Epidemiology Reference Group (CHERG). For the outcome of interest, namely stillbirth, we applied the rules developed by CHERG to recommend a final estimate for reduction in stillbirth for input to the Lives Saved Tool (LiST) model.

RESULTS

A total of 25 studies were included in the review. A random-effects meta-analysis of observational studies of detection and treatment of syphilis during pregnancy showed a significant 80% reduction in stillbirths [Relative risk (RR) = 0.20; 95% confidence interval (CI): 0.12 - 0.34) that is recommended for inclusion in the LiST model. Our meta-analysis showed the malaria prevention interventions i.e. intermittent preventive treatment (IPTp) and insecticide-treated mosquito nets (ITNs) can reduce stillbirths by 22%, however results were not statistically significant (RR = 0.78; 95% CI: 0.59 - 1.03). For human immunodeficiency virus infection, a pooled analysis of 6 randomized controlled trials (RCTs) failed to show a statistically significant reduction in stillbirth with the use of antiretroviral in pregnancy compared to placebo (RR = 0.93; 95% CI: 0.45 - 1.92). Similarly, pooled analysis combining four studies for the treatment of bacterial vaginosis (3 for oral and 1 for vaginal antibiotic) failed to yield a significant impact on perinatal mortality (OR = 0.88; 95% CI: 0.50 - 1.55).

CONCLUSIONS

The clearest evidence of impact in stillbirth reduction was found for adequate prevention and treatment of syphilis infection and possibly malaria. At present, large gaps exist in the growing list of stillbirth risk factors, especially those that are infection related. Potential causes of stillbirths including HIV and TORCH infections need to be investigated further to help establish the role of prevention/treatment and its subsequent impact on stillbirth reduction.

Review of cytomegalovirus seroprevalence and demographic characteristics associated with infection

Cytomegalovirus establishes a lifelong latent infection following primary infection that can periodically reactivate with shedding of infectious virus. Primary infection, reactivation and reinfection during pregnancy can all lead to in utero transmission to the developing fetus. Congenital CMV infections are a major cause of permanent hearing loss and neurological impairment. In this literature review, we found that CMV infection was relatively common among women of reproductive age, with seroprevalence ranging from 45 to 100%. CMV seroprevalence tended to be highest in South America, Africa and Asia and lowest in Western Europe and United States. Within the United States, CMV seroprevalence showed substantial geographic variation as well, differing by as much as 30 percentage points between states, though differences might be explained by variation in the types of populations sampled. Worldwide, seroprevalence among non-whites tended to be 20-30 percentage points higher than that of whites (summary prevalence ratio (PR) = 1.59, 95% confidence interval (CI) = 1.57-1.61). Females generally had higher seroprevalences than males, although in most studies the differences were small (summary PR = 1.13, 95% CI = 1.11-1.14). Persons of lower socioeconomic status were more likely to be CMV seropositive (summary PR = 1.33, 95% CI = 1.32-1.35). Despite high seroprevalences in some populations, a substantial percentage of women of reproductive age are CMV seronegative and thus at risk of primary CMV infection during pregnancy. Future vaccine or educational campaigns to prevent primary infection in pregnant women may need to be tailored to suit the needs of different populations.

Detection of HCMV DNA in placenta, amniotic fluid and fetuses of seropositive women by nested PCR

Human cytomegalovirus (HCMV) is the most common viral cause of intrauterine infection throughout the world. Its distribution patterns in different clinical samples are poorly understood. This study was performed to determine the frequency of CMV DNA positivity in maternal/fetus sera, placentas and amniotic fluid, together with maternal/fetus serology. Clinical specimens were obtained from 92 pregnant women who delivered by cesarean section. 98% of women and their neonates were HCMV IgG positive and 5.4% of these mothers were IgM positive, while no IgM was detected in neonates of IgM positive mothers. Among the IgG positive mothers, IgM was detected in 3.3% of their fetuses. 5.4% and 3.3% of maternal and fetal sera were HCMV DNA positive, respectively. The three neonates who were positive for HCMV DNA in sera were also positive for HCMV IgM and the PCR of their amnions was positive (p < 0.0001). 9.8% of placenta samples and 4.3% of amniotic fluid specimens were positive for HCMV DNA while among these placenta samples, two amnions were PCR positive (p = 0.046). Our results showed that there is not always a correlation between placenta and amnion infections. This may be due to reactivation of HCMV leading to placenta infection, as all affected placentas do not pass infection to fetuses and amniotic fluids. Detection of HCMV DNA in amnion and fetus plasma and the existence of fetus IgM against HCMV can also occur without clinical symptoms.