Karen B. Fowler

The outcome of congenital cytomegalovirus infection in relation to maternal antibody status.

Abstract Background. Intrauterine transmission of cytomegalovirus (CMV) can occur whether a mother has prior immunity or acquires CMV for the first time during pregnancy. The degree of protection afforded an infected infant by the presence of antibody in the mother before conception is uncertain. Methods. We compared the outcomes of CMV-infected infants born to mothers who acquired primary CMV infection during pregnancy (primary-infection group) with those of CMV-infected infants born to mothers with immunity (recurrent-infection group). Screening for viruria identified 197 newborns with congenital CMV infection. Stored serum samples were used to categorize maternal infection as either primary or recurrent. We followed 125 infants from the primary-infection group and 64 from the recurrent-infection group. Serial medical, audiologic, psychometric, and eye examinations were used to identify sequelae of CMV infection. Results. Only infants in the primary-infection group had symptomatic CMV infection at birth...

Intrauterine Transmission of Cytomegalovirus to Infants of Women with Preconceptional Immunity

Background Preconceptional immunity against cytomegalovirus (CMV) provides only partial protection against intrauterine transmission of the virus. Whether congenital CMV infection in the offspring of women who are seropositive for CMV can occur after maternal reinfection with a different strain of CMV is unknown. Methods Serum specimens from 46 women with preconceptional immunity against CMV that were obtained during the previous pregnancy and the current pregnancy were analyzed for antibodies against the strain-specific epitopes of CMV glycoprotein H. Virus-neutralizing activity in maternal serum samples was measured against the AD169 laboratory strain of CMV and the CMV isolates available from seven infected infants. In addition, the nucleotide sequences of the glycoprotein H gene from the seven CMV isolates were determined. Results Eleven of the 16 mothers with infected infants (69 percent) had antibodies against the glycoprotein H epitopes present on two laboratory strains of CMV, AD169 and Towne. Ten...

Progressive and fluctuating sensorineural hearing loss in children with asymptomatic congenital cytomegalovirus infection

OBJECTIVE To determine the prevalence and temporal changes of sensorineural hearing loss (SNHL) among children with clinically inapparent (asymptomatic) congenital cytomegalovirus (CMV) infection identified from a cohort of newborn infants screened for congenital CMV infection. METHODS The study population consisted of 307 children with documented asymptomatic congenital CMV infection, 76 uninfected siblings of children with asymptomatic congenital CMV infection, and 201 children whose neonatal screen for congenital CMV infection showed negative results. Audiologic evaluations were completed for all children to determine their hearing status. RESULTS SNHL occurred only in children with congenital CMV infection. Of the children with asymptomatic congenital CMV infection, 22 (7.2%; 95% confidence interval, 4.5% to 10.6%) had SNHL. Among the children with hearing loss, further deterioration of hearing occurred in 50.0%, with the median age at first progression at 18 months (range, 2 to 70 months). Delayed-onset SNHL was observed in 18.2% of the children, with the median age of detection at 27 months (range, 25 to 62 months). Fluctuating SNHL was documented in 22.7% of the children with hearing loss. CONCLUSIONS Asymptomatic congenital CMV infection is likely a leading cause of SNHL in young children. The continued deterioration of hearing and delayed onset of SNHL in these children emphasizes the need for continued monitoring of their hearing status.

Symptomatic Congenital Cytomegalovirus Infection in Infants Born to Mothers With Preexisting Immunity to Cytomegalovirus

Objectives. To determine the frequency of symptomatic congenital cytomegalovirus (CMV) infection in the offspring of women with a recurrent maternal CMV infection and to characterize the demographic and newborn findings. Methods. Study subjects consisted of infants with symptomatic congenital CMV infection identified by a newborn virologic screening program at the University of Alabama Hospital between 1991 and 1997 and were enrolled in a long-term follow-up study. Maternal infections were categorized by an analysis of archival serum specimens collected before pregnancy and at the time of delivery. Demographic data and clinical findings at birth were collected from maternal and newborn hospital records and from parents at the time of initial evaluation. Results. Of the 47 infants with symptomatic congenital CMV infection identified during the study period, 8 were born to mothers with a confirmed nonprimary or recurrent CMV infection. The type of maternal infection could be ascertained in only ∼43% (20/47) of the children with symptomatic congenital CMV infection born at the University of Alabama Hospital during the study period. There were no significant differences in demographic characteristics of the recurrent infection group and the infants who were born to mothers with either primary CMV infection during pregnancy or unclassified maternal infection. Similarly, the range of severity of clinical abnormalities during the newborn period did not differ in the two groups of children. Furthermore, there were no significant differences in the incidence of sequelae at long-term follow-up in the two groups of children. Conclusions. Symptomatic congenital CMV infection can occur after a nonprimary or recurrent maternal infection. However, the exact incidence of symptomatic congenital CMV infection among children born to women with preexisting immunity remains to be defined.

NEWBORN HEARING SCREENING: WILL CHILDREN WITH HEARING LOSS CAUSED BY CONGENITAL CYTOMEGALOVIRUS INFECTION BE MISSED?

Abstract Objective: To predict whether universal newborn auditory screening will identify most infants with sensorineural hearing loss (SNHL) caused by congenital cytomegalovirus (CMV) infection. Study design: A cohort of 388 children born between 1980 and 1996 at one hospital and identified during the newborn period as having congenital CMV infection received repeated hearing evaluations to assess whether hearing loss had occurred. Results: SNHL was detected in 5.2% of all infants at birth. Late-onset SNHL occurred among the children throughout the first 6 years of life. By the age of 72 months, the cumulative incidence of SNHL was 15.4% in the cohort. Children with clinically apparent disease at birth had significantly more SNHL than children without any apparent disease (22.8% vs 4.0% at 3 months and 36.4% vs 11.3% at 72 months of age). Conclusions: Universal screening of hearing in neonates will detect less than half of all SNHL caused by congenital CMV infection. Because most infants with congenital CMV infection are without symptoms at birth, these children are unlikely to be recognized as being at risk for SNHL and will not receive further hearing evaluations to detect late-onset hearing loss. A combined approach of universal screening of neonates for hearing, as well as for detection of congenital CMV infection, needs to be considered. (J Pediatr 1999;135:60-4)

Saliva Polymerase-Chain-Reaction Assay for Cytomegalovirus Screening in Newborns

BACKGROUND Congenital cytomegalovirus (CMV) infection is an important cause of hearing loss, and most infants at risk for CMV-associated hearing loss are not identified early in life because of failure to test for the infection. The standard assay for newborn CMV screening is rapid culture performed on saliva specimens obtained at birth, but this assay cannot be automated. Two alternatives--real-time polymerase-chain-reaction (PCR)-based testing of a liquid-saliva or dried-saliva specimen obtained at birth--have been developed. METHODS In our prospective, multicenter screening study of newborns, we compared real-time PCR assays of liquid-saliva and dried-saliva specimens with rapid culture of saliva specimens obtained at birth. RESULTS A total of 177 of 34,989 infants (0.5%; 95% confidence interval [CI], 0.4 to 0.6) were positive for CMV, according to at least one of the three methods. Of 17,662 newborns screened with the use of the liquid-saliva PCR assay, 17,569 were negative for CMV, and the remaining 85 infants (0.5%; 95% CI, 0.4 to 0.6) had positive results on both culture and PCR assay. The sensitivity and specificity of the liquid-saliva PCR assay were 100% (95% CI, 95.8 to 100) and 99.9% (95% CI, 99.9 to 100), respectively, and the positive and negative predictive values were 91.4% (95% CI, 83.8 to 96.2) and 100% (95% CI, 99.9 to 100), respectively. Of 17,327 newborns screened by means of the dried-saliva PCR assay, 74 were positive for CMV, whereas 76 (0.4%; 95% CI, 0.3 to 0.5) were found to be CMV-positive on rapid culture. Sensitivity and specificity of the dried-saliva PCR assay were 97.4% (95% CI, 90.8 to 99.7) and 99.9% (95% CI, 99.9 to 100), respectively. The positive and negative predictive values were 90.2% (95% CI, 81.7 to 95.7) and 99.9% (95% CI, 99.9 to 100), respectively. CONCLUSIONS Real-time PCR assays of both liquid- and dried-saliva specimens showed high sensitivity and specificity for detecting CMV infection and should be considered potential screening tools for CMV in newborns. (Funded by the National Institute on Deafness and Other Communication Disorders.).

DRIED BLOOD SPOT REAL-TIME POLYMERASE CHAIN REACTION ASSAYS TO SCREEN NEWBORNS FOR CONGENITAL CYTOMEGALOVIRUS INFECTION

CONTEXT Reliable methods to screen newborns for congenital cytomegalovirus (CMV) infection are needed for identification of infants at increased risk of hearing loss. Since dried blood spots (DBS) are routinely collected for metabolic screening from all newborns in the United States, there has been interest in using DBS polymerase chain reaction (PCR)-based methods for newborn CMV screening. OBJECTIVE To determine the diagnostic accuracy of DBS real-time PCR assays for newborn CMV screening. DESIGN, SETTING, AND PARTICIPANTS Between March 2007 and May 2008, infants born at 7 US medical centers had saliva specimens tested by rapid culture for early antigen fluorescent foci. Results of saliva rapid culture were compared with a single-primer (March 2007-December 2007) and a 2-primer DBS real-time PCR (January 2008-May 2008). Infants whose specimens screened positive on rapid culture or PCR had congenital infection confirmed by the reference standard method with rapid culture testing on saliva or urine. MAIN OUTCOME MEASURES Sensitivity, specificity, and positive and negative likelihood ratios (LRs) of single-primer and 2-primer DBS real-time PCR assays for identifying infants with confirmed congenital CMV infection. RESULTS Congenital CMV infection was confirmed in 92 of 20,448 (0.45%; 95% confidence interval [CI], 0.36%-0.55%) infants. Ninety-one of 92 infants had positive results on saliva rapid culture. Of the 11,422 infants screened using the single-primer DBS PCR, 17 of 60 (28%) infants had positive results with this assay, whereas, among the 9026 infants screened using the 2-primer DBS PCR, 11 of 32 (34%) screened positive. The single-primer DBS PCR identified congenital CMV infection with a sensitivity of 28.3% (95% CI, 17.4%-41.4%), specificity of 99.9% (95% CI, 99.9%-100%), positive LR of 803.7 (95% CI, 278.7-2317.9), and negative LR of 0.7 (95% CI, 0.6-0.8). The positive and negative predictive values of the single-primer DBS PCR were 80.9% (95% CI, 58.1%-94.5%) and 99.6% (95% CI, 99.5%-99.7%), respectively. The 2-primer DBS PCR assay identified infants with congenital CMV infection with a sensitivity of 34.4% (95% CI, 18.6%-53.2%), specificity of 99.9% (95% CI, 99.9%-100.0%), positive LR of 3088.9 (95% CI, 410.8-23 226.7), and negative LR of 0.7 (95% CI, 0.5-0.8). The positive and negative predictive values of the 2-primer DBS PCR were 91.7% (95% CI, 61.5%-99.8%) and 99.8% (95% CI, 99.6%-99.9%), respectively. CONCLUSION Among newborns, CMV testing with DBS real-time PCR compared with saliva rapid culture had low sensitivity, limiting its value as a screening test.

Cytomegalovirus Reinfections in Healthy Seroimmune Women

Cytomegalovirus (CMV) reinfections have been associated with damaging congenital infection and adverse outcomes in transplant recipients. To determine the frequency of and risk factors for CMV reinfections, 205 seropositive women were followed up prospectively. The appearance of new antibody specificity against 1 of 4 polymorphic epitopes was considered as evidence of CMV reinfection. Approximately one-third of the study participants (59 [29%] of 205) were noted to have CMV reinfection during follow-up. None of the exposure factors were associated with CMV reinfection. Women with antibodies against at least 1 of the 4 antigens at baseline had a 63% decreased risk of reinfection, suggesting a protective role for strain-specific immunity.

Risk factors for congenital cytomegalovirus infection in the offspring of young women: exposure to young children and recent onset of sexual activity.

OBJECTIVE. Two recognized sources of maternal cytomegalovirus infection are young children and sexual activity. Previous studies evaluated either maternal exposures to young children or sexual activity, but these studies did not evaluate whether both of these maternal cytomegalovirus sources contribute to increases in congenital cytomegalovirus infections within populations with a high prevalence of infection among women of childbearing age. Our objective with this study was to investigate whether maternal cytomegalovirus exposure through young children and by sexual activity increases the risk for congenital cytomegalovirus infection in their offspring. METHODS. A case-control study of 519 women from a delivery population in Birmingham, AL, between December 1992 and July 1998 was undertaken to measure the association between maternal cytomegalovirus exposures and an increased risk for congenital cytomegalovirus infection in their infants. Routine newborn cytomegalovirus screening at the hospital identified infants with congenital cytomegalovirus infection. The cases (n = 150) were women who delivered an infant with congenital cytomegalovirus infection, and the control subjects (n = 369) were randomly selected from the delivery population of women whose newborns were uninfected. Investigation of exposures included using a standardized maternal interview, prenatal and medical chart abstraction, and laboratory confirmation of cytomegalovirus infection. RESULTS. Significant associations between congenital cytomegalovirus infection and caring for preschool children in the year before delivery, onset of sexual activity <2 years before delivery, sexually transmitted diseases during pregnancy, household size >3 people, and maternal age <25 years were identified. Women who cared for preschool children in the year before delivery and also became sexually active within the 2 years before delivery were at greatest risk for delivering an infant with congenital cytomegalovirus infection. CONCLUSIONS. Caring for young children and recent onset of sexual activity contribute to an increased risk for congenital cytomegalovirus infection in the offspring of young women.

Congenital cytomegalovirus infection and neonatal auditory screening.

Auditory screening of newborn infants has been recommended on the basis of the presence of risk criteria, including congenital infection. We assessed the ability of risk criteria-based neonatal auditory brain stem response to identify infants with hearing loss resulting from congenital cytomegalovirus (CMV) infection. Data from 6 1/2 years of risk criteria-based neonatal auditory screening were compared with the results of screening of all newborn infants for congenital CMV infection. Infants with congenital CMV infection received follow-up hearing evaluations. Congenital CMV infection was found in 167 (1.3%) of 12,371 infants; 134 had follow-up hearing evaluations, and 14 (10.4%) had confirmed sensorineural hearing loss. The rate of sensorineural hearing loss resulting from congenital CMV infection was 14 per 12,371 infants, of 1.1 per 1000 live births; the rate of bilateral loss > or = 50 dB was 0.6 per 1000. Although 2036 infants received auditory screening because of risk criteria, only 34 (20%) of 167 infants with congenital CMV infection were included. Only 2 (14%) of 14 children with sensorineural hearing loss caused by CMV were identified by risk criteria-based screening. We conclude that congenital CMV infection is an important cause of hearing impairment. Neonatal auditory screening based on the presence of risk criteria will fail to identify the majority of cases of sensorineural hearing loss caused by congenital CMV infection.