Toshio Minematsu

Seroepidemiological survey of cytomegalovirus infection among pregnant women in Nagasaki, Japan

Background:  Epidemiology of cytomegalovirus (CMV) infection varies widely, depending on ethnicity and socioeconomic status. A seroepidemiological survey was conducted to determine CMV infection among pregnant women in Nagasaki Prefecture, Japan.

Fetal manifestations and poor outcomes of congenital cytomegalovirus infections: Possible candidates for intrauterine antiviral treatments

Aim:  This retrospective study was performed to reveal the natural history of cytomegalovirus (CMV) infected fetuses during the perinatal period and to find prenatal findings associated with poor outcomes.

Low IgG avidity and ultrasound fetal abnormality predict congenital cytomegalovirus infection

Cytomegalovirus (CMV) causes congenital infection with high mortality and morbidity rates in affected neonates. The aim of this study was to assess whether prenatal clinical or laboratory findings in pregnant women who had high risks for primary CMV infection predicted the presence of congenital infection. Fifty pregnant women who had serum CMV IgG and positive or borderline tests for serum CMV IgM were included in this prospective study. Serum IgG avidity was measured, and PCR was conducted for CMV DNA in maternal serum, urine, and uterine cervical secretion. All neonates underwent PCR testing for CMV DNA in the urine for the presence of congenital infection. Risk factors were compared between congenital infection group and group without congenital infection. As a result, nine neonates (18%) were diagnosed as having congenital infection. The frequencies of ultrasound fetal abnormality and positive test for CMV DNA in cervical secretion, CMV IgM titer and IgM/IgG ratio in the congenital infection group were significantly higher than those in the group without congenital infection. Conversely, IgG avidity index in the congenital infection group was significantly lower than that in the group without congenital infection. By multivariate logistic regression analyses, IgG avidity index (Odds ratio 0.91, 95% CI: 0.83–0.99) and ultrasound fetal abnormality (291.22, 2.72–31125.05), were selected independently as significant signs predictive of congenital CMV infection. Among pregnant women with positive or borderline tests for CMV IgM, when they have findings of low serum CMV IgG avidity or ultrasound fetal abnormality, the probability of congenital CMV infection may increase. J. Med. Virol. 84:1928–1933, 2012.

Cytomegalovirus (CMV) glycoprotein H-based serological analysis in Japanese healthy pregnant women, and in neonates with congenital CMV infection and their mothers

BACKGROUND Congenital cytomegalovirus (CMV) infection is caused by maternal primary infection as well as CMV reinfection or reactivation during pregnancy, although differences in the clinical impact between these modes of infection remain to be clarified. OBJECTIVES To investigate the latest prevalence and risk of multiple CMV infection in healthy pregnant women, as well as the types of maternal CMV infection associated with congenital CMV infection. STUDY DESIGN Seroprevalence against CMV and IgG subclasses were determined in 344 serum samples from healthy pregnant women in Japan. CMV genotype and serotype were also determined in 18 pairs of mothers and neonates with congenital CMV infection identified in our CMV screening program. RESULTS Thirty-two percent of the pregnant women were seronegative, while 66% of CMV seropositive women had IgG3 antibodies against one epitope on glycoprotein H (gH) as the major subclass, and 52% had IgG1 antibodies against one epitope on glycoprotein B (gB). Only a single genotype determined by CMV gH neutralizing epitope was found in the urine from the 18 neonates with congenital CMV infection, even though one case possessed antibodies against multiple CMV strains. In that case, the antibodies against the strain not detected in the urine from the infant disappeared within one month after birth, whereas the antibodies against the infecting CMV strain continued to be detected at 12 months after birth. CONCLUSIONS Two (11%) of 18 cases of congenital CMV infection occurred via maternal CMV reinfection. Maternal humoral immunity did not prevent congenital CMV infection with another gH subtype.

Single cytomegalovirus strain associated with fetal loss and then congenital infection of a subsequent child born to the same mother.

BACKGROUND Intrauterine transmission of cytomegalovirus (CMV) can occur even in CMV-seropositive mothers. Previous studies demonstrated re-infection with a newly acquired CMV strain during pregnancy had a major role in such transmission. Although reactivation of latently infected CMV is another plausible cause, no direct evidence has been documented. OBJECTIVES We sought to identify the route(s) and maternal risk factor of CMV infection that occurred in consecutive pregnancies and resulted in symptomatic congenital infections. STUDY DESIGN A newborn identified with congenital CMV infection in our newborn screening program developed hearing loss and subsequent nystagmus. The mother had a history of an elective abortion due to a severe fetal CMV infection 32 months prior to delivery of this newborn. We analyzed maternal serological changes and compared CMV genomic sequences in specimens obtained from the aborted fetus and the present case. We also analyzed immunological functions of the mother. RESULTS Our major findings were as follows: (1) the aborted fetus and the present case were infected with the same strain. (2) The congenital infection that resulted in the abortion was due to a primary infection. (3) CMV DNA was undetectable in the mothers blood from 3 months after the abortion. These results strongly suggested that maternal viral reactivation caused the congenital infection in the present case. However, we could not find impairment of immunological functions in the mother. CONCLUSIONS Viral reactivation in an apparently immunocompetent mother can cause symptomatic congenital CMV infection.

Rapid increase in the serum Cytomegalovirus IgG avidity index in women with a congenitally infected fetus

BACKGROUND Human Cytomegalovirus (CMV) is the virus most frequently responsible for severe diseases of the fetus and newborn. The reported intrauterine transmission rate of CMV following primary maternal infection is approximately 40%. Invasive techniques are needed for the prenatal diagnosis of congenital CMV infection. OBJECTIVES The aim of this study was to evaluate whether the rapidity of change in the CMV IgG avidity index (AI) is associated with the presence of congenital CMV infection among mothers with suspected primary CMV infection. STUDY DESIGN The serum CMV IgG AI was repeatedly measured in 17 pregnant women with positive or borderline test results for CMV IgM together with an initial IgG AI value of <40%. Their neonates underwent polymerase chain reaction analyses for the presence of CMV DNA in the urine. The rapidity of change in the IgG AI per 4 weeks was defined as the ΔAI (%). The ΔAI of women with congenital CMV infection was compared with that of women with no infection. RESULTS The ΔAI of nine mothers with congenital CMV infection (median,15.7%; range,7.8-42.8%) was significantly higher than that of eight mothers with no infection (median, 6.5%, range, 2.0-8.8%; p<0.001). The incidences of congenital CMV infection were 100.0%, 16.7%, and 0.0% among mothers with a ΔAI of >10, 5-10, and <5%, respectively. CONCLUSIONS Measurement of the ΔAI in pregnant women might be useful for estimating the risk of mother-to-neonate CMV transmission.

The IgG avidity value for the prediction of congenital cytomegalovirus infection in a prospective cohort study.

Abstract Background: Cytomegalovirus (CMV) causes congenital infection with high mortality and morbidity rates in affected neonates. Objectives: To evaluate the maternal IgG avidity value for the prediction of congenital CMV infection. Study design: The serum IgG avidity in all mothers was measured, and the urine of their neonates was assessed for CMV DNA in a prospective cohort study. Results: Of 759 women with a positive test for CMV IgG, 14 had congenital CMV infection. CMV IgG avidity indices in the congenital infection group (median 35.1%) were significantly lower than those in the non-congenital infection group (70.4%). A cutoff value of <40% IgG avidity index with 96.1% specificity and 64.3% sensitivity for congenital infection was determined by receiver operating characteristic curve analyses. The highest sensitivity (88.9%), 96.2% specificity, 27.6% positive predictive value, 99.8% negative predictive value, and 96.1% accuracy were found when IgG avidity was measured in <28 weeks of gestation. Conclusion: The IgG avidity measurement with a cutoff value of <40% IgG avidity index might be helpful in predicting congenital CMV infection, especially in <28 weeks of gestation.

Universal Screening With Use of Immunoglobulin G Avidity for Congenital Cytomegalovirus Infection

Background The aim of this prospective cohort study was to evaluate the efficacy of maternal screening for congenital cytomegalovirus infection (CCI) using cytomegalovirus (CMV) immunoglobulin G (IgG) and the IgG avidity index (AI). Methods Pregnant women underwent screening of CMV IgG and AI measurements. IgG-negative women underwent remeasurement of IgG after educational intervention. Women with an AI ≤45% received further examinations, including measurement of CMV IgM. All newborns received polymerase chain reaction analyses of the urine, and CCI was diagnosed by the detection of CMV-DNA in the urine. Primary infection was defined as an AI <35% and/or positive IgM (>1.20 index). Serum samples from women with an AI >45% were stored, and the IgM levels were measured after delivery. The efficacy of AI and IgM for CCI screening was compared. Results A total of 1562 (71.2%) women tested positive for IgG. In this study, 10 newborns with CCI were detected. The presence of infection in 3 newborns from mothers with primary infection was predicted by screening of IgG and AI <35%. However, infection in 7 newborns from women with nonprimary infection could not be predicted by screening of CMV IgG, AI <35%, or IgM. The application of an AI <35% for CCI screening yielded 22.2% sensitivity, 95.0% specificity, 2.5% positive predictive value, and 99.5% negative predictive value and was similar to that of IgM (11.1% sensitivity, 93.2% specificity, 0.9% positive predictive value, and 92.7% negative predictive value). Conclusions Maternal screening using CMV IgG and AI can identify pregnancies with CCI from primary infection, but overlooks a number of those from nonprimary infection.

Prediction of Congenital Cytomegalovirus Infection in High-Risk Pregnant Women

Background. This prospective study aimed to determine maternal clinical, laboratory, and ultrasound findings that effectively predict the occurrence of congenital cytomegalovirus (CMV) infection (CCI) in high-risk pregnant women. Methods. Three hundred CMV immunoglobulin (Ig) M–positive pregnant women were enrolled. The maternal clinical and laboratory findings, including serum CMV IgM and IgG; IgG avidity index (AI); antigenemia assay (C7-HRP); polymerase chain reaction (PCR) for the detection of CMV-DNA in the maternal serum, urine, and uterine cervical secretion; and prenatal ultrasound findings, were evaluated. To determine predictive factors for the occurrence of CCI, logistic regression analyses were performed. Results. In 22 of the 300 women, CCI was confirmed using PCR for CMV-DNA in newborn urine. Univariate analyses demonstrated that the presence of maternal flu-like symptoms, presence of ultrasound fetal abnormalities, serum titers of CMV IgM, positive results for C7-HRP, CMV IgG AI <40%, and positive PCR results in the uterine cervical secretion were statistically associated with the occurrence of CCI. Multivariable analysis revealed that the presence of ultrasound fetal abnormalities (odds ratio [OR], 31.9; 95% confidence interval [CI], 8.5–120.3; P < .001) and positive PCR results in the uterine cervical secretion (OR, 16.4; 95% CI, 5.0–54.1; P < .001) were independent predictive factors of CCI in CMV IgM-positive women. Conclusions. This is the first prospective cohort study to suggest that the presence of CMV-DNA in the maternal uterine cervical secretion and ultrasound fetal abnormalities are predictive of the occurrence of congenital CMV infection in high-risk pregnant women.

Rubella outbreak on Tokunoshima Island in 2004: serological and epidemiological analysis of pregnant women with rubella.

Aim:  This paper presents the serological and epidemiological background of the rubella‐infected pregnant women following the rubella outbreak throughout Tokunoshima Island that occurred after the revision of the immunization law in Japan.