[Effects of cytomegalovirus infection in pregnant women to fetuses: study with DNA-DNA hybridization method]

DNA of cytomegalovirus (CMV) was examined in 131 placentae and 28 umbilical blood specimens by DNA-DNA hybridization. The result revealed that CMV DNA was detected in 4 of 50 placentae from abnormal fetuses (31 fetal deaths, 19 fetal deformities). 77 placentae from normal fetuses showed negative results. One of 2 cord blood samples from fetal deformities showed CMV DNA positive. 25 umbilical blood samples from normal term newborns showed negative. 4 placentae and 1 cord blood sample from premature infants showed negative results. The results indicate that CMV may play a great role in fetal death and fetal deformity through the infected maternal-fetal circulation.

IgM antibody to Treponema pallidum in cerebrospinal fluid of infants with congenital syphilis

OBJECTIVES

To characterize the neonatal IgG and IgM response to specific Treponema pallidum antigens in the cerebrospinal fluid (CSF) of infants with congenital syphilis.

DESIGN

Cross-sectional survey.

SETTING

Newborn nursery and neonatal intensive care unit of a county hospital in Dallas, Tex.

PARTICIPANTS

Twenty-one infants born to mothers with reactive serologic tests for syphilis were enrolled. Group 1 consisted of six infants with clinical and laboratory evidence of congenital syphilis; group 2, six asymptomatic infants born to mothers with untreated syphilis; and group 3, nine asymptomatic infants whose mothers were treated for syphilis before delivery.

SELECTION PROCEDURES

Random sample.

MEASUREMENTS AND RESULTS

Immunoblotting was used to examine the IgM and IgG reactivities of neonatal serum and CSF against T pallidum antigens. Among serum samples of all group 1 infants, a specific IgM response to T pallidum antigens with apparent molecular masses of 47, 45, and 17 kd was observed. Cerebrospinal fluid IgM reactivity to a 47-kd antigen of T pallidum was seen in four group 1 infants. Serum samples from two group 2 and three group 3 infants demonstrated IgM reactivity against the 47-kd antigen and, in some cases, against the 45-kd antigen of T pallidum. None of 15 group 2 and 3 infants had a positive CSF IgM immunoblot result. The IgG reactivity in CSF was similar in the three groups and was directed against T pallidum antigens with apparent molecular masses of 72, 59, 47, 45, 42, 37, 34, 17, and 15 kd.

CONCLUSIONS

A specific IgM response to T pallidum antigens, particularly the 47-kd antigen, was detected in the CSF of some infants with clinical and laboratory evidence of congenital syphilis. The potential usefulness of this test for the diagnosis of congenital neurosyphilis merits further study.

Fetal blood sampling in human immunodeficiency virus--seropositive women before elective midtrimester termination of pregnancy

OBJECTIVES

To explore the diagnostic potential of fetal blood sampling in the prenatal diagnosis of intrauterine human immunodeficiency virus infection and to investigate the transplacental transfer of human immunodeficiency virus antibody and p24 antigen in the second trimester of pregnancy, we studied serum and amniotic fluid obtained from 13 seropositive women and their fetuses before elective termination of pregnancy.

STUDY DESIGN

Enzyme-linked immunosorbent assay, Western blot antibody analyses, and p24 antigen assays were performed on all samples.

RESULTS

Human immunodeficiency virus antibody was detected by enzyme-linked immunosorbent assay and Western blot analysis in aliquots of maternal serum, amniotic fluid, and fetal serum from all 13 pregnancies. Each mother-fetus pair had identical antibody banding patterns. In contrast, p24 antigen was found in the maternal serum and amniotic fluid samples from five of 13 women (38%) and in serum from only three of 13 fetuses (23%).

CONCLUSIONS

We conclude that fetal blood sampling, if combined with sophisticated serologic analysis, may have the potential to provide the diagnosis of congenital infection with human immunodeficiency virus. The correlation of immunologic, virologic, and molecular biologic methods with subsequent infant outcome and risk of iatrogenic infection of the fetus remains to be determined.

Seroprevalence of human immunodeficiency virus in parturients at Boston City Hospital: implications for public health and obstetric practice

OBJECTIVE

We measured the seroprevalence of human immunodeficiency virus in women seeking reproductive services.

STUDY DESIGN

Demographic and risk behavior data from women were linked anonymously to human immunodeficiency virus antibody results.

RESULTS

The overall human immunodeficiency virus seropositivity rate of cord blood was 22 per 1000. Crude seroprevalence rates were higher for black women versus white women (25/1000 vs 22/1000) but lower for black Americans versus white Americans (21/1000 vs 29/1000). Human immunodeficiency virus infection was significantly higher for those women who acknowledge intravenous drug use (odds ratio 12.9, 95% confidence interval 7.3 to 22.7), were born in Haiti (odds ratio 2.6, 95% confidence interval 1.6 to 4.1), lacked prenatal care (odds ratio 2.2, 95% confidence interval 1.1 to 4.2), or received prenatal care at the hospital clinic versus a neighborhood health center (odds ratio 3.0, 95% confidence interval 1.7 to 5.3). The seroprevalence rates were 18/1000 for women seeking abortion and 16/1000 for women seeking family-planning services.

CONCLUSION

Intravenous drug use and country of origin are major risk factors for human immunodeficiency virus infection in women, which may explain differences in seroprevalence rates in various racial or ethnic groups. Hospital-specific data on human immunodeficiency virus infection may be useful for monitoring the epidemic and allocating resources for education, counseling, testing, and prevention.

Maternal transmission of HTLV-1 other than through breast milk: discrepancy between the polymerase chain reaction positivity of cord blood samples for HTLV-1 and the subsequent seropositivity of individuals

We used a nested polymerase chain reaction (PCR) to diagnose HTLV-1 carriers. The DNA isolated from the nuclear extract obtained from frozen whole blood was found appropriate for PCR study both qualitatively and quantitatively. The use of freshly frozen whole blood made the field work much easier, and the use of a nuclear extraction procedure allowed DNA isolation in just 4 microcentrifuge tubes. We could not attain sufficient sensitivity to detect a single molecule with single-step PCR, but nested PCR was confirmed to detect a single molecule/reaction. All samples of the seropositive group including 94 blood donors, 66 mothers, and 13 children were positive in the nested PCR, while none of the seronegative group, including 198 blood donors and 285 children, was positive. Although 18/717 (2.5%) cord blood samples obtained from babies born to carrier mothers were PCR-positive, none of 5 formula-fed children tested who had been PCR-positive in the cord blood gave evidence of infection later on. Furthermore, all of 4 seropositive infected children who were formula-fed had been PCR-negative in their cord blood. The results are not consistent with intrauterine infection, but suggest the presence of a perinatal or postnatal infection route other than through breast milk.

[Monitoring of maternal-fetal hepatitis B virus transmission by molecular hybridization technique]

Maternal venous blood (MB), umbilical blood (UB) and placental tissue (PT) were collected from 40 HBsAg positive mothers and their neonates, and also blood from 17 babies aged 3-6 months old of this group (BB). All samples were determined for hepatitis B virus (HBV) DNA by molecular hybridization technique using Bio-HBV DNA probe. The results showed: HBV DNA positive rate of MB was 35.0%, 47.5% for UB, 75.0% for PT and 29.4% for BB. 32 P-HBV DNA probe was also used to examine MB and PT. The positive rates of HBV DNA were 30.0% and 70.0% respectively. There was no significant difference between the results of the 2 probes. We considered: (1) With the rapid development of HBV detection technique, the detectable rate of intrauterine infection increases accordingly. (2) Besides transplacental infection, other transmission routes might be existed. (3) The detection of HBV DNA in UB, PT and in the blood of babies born by HBV DNA positive mother within 6 months old provides the reliable diagnosis. (4) HBV DNA molecular hybridization is an accurate and sensitive method for the diagnosis of HBV intrauterine infection.

Parvovirus B19 replication in human umbilical cord blood cells

The human parvovirus B19 is now known to be one of the causative agents of nonimmune hydrops fetalis and spontaneous abortions in pregnant women. The presence of the viral proteins and antibodies in fetuses of B19-infected women suggests that the virus can cross the placental barrier. In order to gain an insight into the mechanism of intrauterine fetal infection and the virus-induced hydrops fetalis, we examined whether human umbilical cord blood cells were permissive for B19 replication. Cord blood cells were infected with B19 in vitro, and Southern blot analyses of low M(r) DNA isolated from these cells revealed the presence of the characteristic replicative intermediates of B19 DNA. In addition, B19 genome expression in cord blood cells was detected by Northern blot analysis. Quantitative DNA dot blot analysis of culture supernatants documented complete assembly and release of B19 progeny virions in these cells. The progeny virions were biologically active in secondary infections of normal human bone marrow cells. The human umbilical cord blood cells may be a useful alternative to bone marrow and fetal liver culture systems for further studies on B19 since the need for bone marrow donors is obviated and, unlike fetal tissues, there are no ethical questions associated with the experimental use of cord blood because it is normally discarded. These studies also suggest that the umbilical cord blood may be a site for active replication of parvovirus B19 in vivo and may thus provide a means for transmission of the virus during intrauterine fetal infections.

TORCH infections. Diagnosis in the molecular age

TORCH agents cause a varied spectrum of disease. Advances in ultrasound, invasive perinatal procedures and molecular diagnostics have allowed in utero evaluation. Infected fetuses, especially those which are sonographically abnormal, may be treated in utero depending upon the pathogen and attendant pathophysiology. Subclinical perinatal infections may lead to later childhood deficits. Such infected fetuses may benefit from early diagnosis and prompt initiation of rehabilitative measures.

Laboratory diagnosis of congenital human cytomegalovirus infection using polymerase chain reaction and shell vial culture

Congenital HCMV infection was diagnosed at the 22th week of gestation. The infection was suspected because HCMV IgM was detected in a serum sample obtained from the woman's husband. HCMV infection was detected in the amniotic fluid by polymerase chain reaction, shell vial culture (immunoperoxidase assay) and conventional virus isolation. Serologic testing in paired sera of the woman and in umbilical cord blood for specific IgM and IgA remained negative. As serological data (preconceptional HCMV serostatus) were incomplete, a clear differentiation between primary and secondary infection could not be achieved; consequently, risk quantification could not be determined. Viruria was detected in the offspring during the 1st week post partum. No clinical signs of cytomegalic inclusion disease were diagnosed up to six weeks post partum. Our case report indicates that for pregnancy surveillance, serologic testing for HCMV antibody should also be performed in the spouse.

Peripheral blood mononuclear cells of the elderly contain varicella-zoster virus DNA

Peripheral blood mononuclear cells (PBMC) from humans of different ages were analyzed for DNA sequences specific for varicella-zoster virus (VZV) genes 29 and 62 by polymerase chain reaction (PCR). Neither VZV gene was detected in DNA from umbilical cord blood PBMC of 10 infants or from blood PBMC of two 3-year-old children. In 22 humans less than 60 years old, gene 29 was not detected, and gene 62 was detected in only one subject. In 33 humans greater than 60 years old, including patients with postherpetic neuralgia, PBMC from 4 subjects contained gene 29, 4 contained gene 62, and 1 contained both genes. The presence of VZV DNA correlated significantly with age (P less than .05, chi 2 and logistic regression analysis), but not with gender or postherpetic neuralgia.

Infection of bovine fetuses at 120 days' gestation with virulent and avirulent strains of bluetongue virus serotype 11

Bluetongue virus infection in sheep and cattle during fetal development causes neuropathology. Two strains of bluetongue virus serotype 11 designated as UC-2 and UC-8 have different virulence patterns in newborn mice. These viruses have distinctly different electropherotype patterns on polyacrylamide gel electrophoresis indicating a genetic difference in these two viruses of the same serotype. Four bovine fetuses each were inoculated intramuscularly with either UC-2 or UC-8, and one fetus was inoculated with placebo. The inoculation was made intramuscularly through the uterine wall at 120 days' gestation, and the bovine fetuses were recovered by cesarean section 12 or 20 days after inoculation. Fetal blood was collected for virus isolation and serology. Virus was reisolated from brain, blood, lung and liver. Both strains, UC-2 and UC-8, cause severe lesions in the 120 day fetuses. The encephalomalacic lesions occurred earlier and were more severe in fetuses inoculated with UC-8 as compared to those inoculated with UC-2. The subtle differences observed in the fetuses inoculated with the two different strains suggest that there is a difference in pathogenic potential of the two viruses. These differences do not appear to be completely dependent upon the host species.

Retrieval of placental blood from the umbilical vein to determine volume, sterility, and presence of clot formation

From August 1988 to October 1989, 60 specimens of citrate-phosphate-dextrose-adenine anticoagulated blood were retrieved from the placental umbilical veins of newborns from three gestational age groups. The specimens were removed with a needle and syringe apparatus and placed directly into sterile transfusion packs. The specimens were evaluated for the volume obtained, sterility, and presence of macroscopic clots. A blood volume sufficient to provide at least one transfusion (10 mL/kg) for 87% of the premature infants studied was retrieved from the placenta. A greater blood volume per unit of birth weight was recovered from the placentas of the smaller newborns. A 12% positive culture frequency and a 7% frequency of detectable clots were identified. These rates of occurrence suggest the need for further studies to determine the origins of these complicating factors before the adoption of this technique in the clinical setting. These findings support the hypothesis that, with proper patient selection and with specimen culture and filtration, placental blood may be a viable option for the autologous transfusion of sick, premature infants.

Infection of cord blood monocyte-derived macrophages with human immunodeficiency virus type 1

We have investigated the susceptibility of cord blood monocyte-derived macrophages to human immunodeficiency virus type 1 (HIV-1) infection in vitro. Cord blood monocytes were maintained in vitro for 10 to 15 days and then infected with HIV-1. Syncytia were observed 14 days after infection by light microscopy. Viral proteins were detected by immunofluorescence assay. Electron microscopic examination demonstrated typical lentivirus particles within cytoplasmic vacuoles. The supernatants from the HIV-1-infected cultures also contained significant reverse transcriptase activity and p24 antigen. Like adult monocyte/macrophages, cord-derived monocyte/macrophages expressed the CD4 receptor molecule. Pretreatment with blocking antibody prior to infection with HIV-1 Bal significantly reduced or blocked infection of cord monocyte/macrophages. When cord and adult monocyte/macrophages were infected with HIV-1 Bal or Ada-M and directly compared, higher reverse transcriptase activities and p24 antigen expression were obtained with cord monocyte/macrophages. However, no significant difference was found between adult and cord monocyte/macrophages infected with HIV-1 IIIB. These observations suggest that cord monocyte-derived macrophages may be important in the pathogenesis of pediatric AIDS and that the increased susceptibility of cord monocyte/macrophages to HIV-1 infection in vitro may be relevant to the enhanced susceptibility of neonates to HIV-1 diseases in vivo.

Possible transplacental transmission of human papillomaviruses

OBJECTIVE

The objective of this study was to examine the possibility of intrauterine human papillomavirus infection of fetuses by transplacental transmission of human papillomavirus before delivery.

STUDY DESIGN

Specimens of cervicovaginal cells and peripheral blood mononuclear cells were obtained from 52 consecutive pregnant women in the third trimester of pregnancy. Cord blood specimens were also obtained from the neonates born to these mothers. Presence of human papillomavirus types 16 and 18 deoxyribonucleic acid was analyzed by an in vitro enzymatic deoxyribonucleic acid amplification method.

RESULTS

Human papillomavirus type 16 deoxyribonucleic acid was found in 6 (11.5%) cervicovaginal and in 9 (17.3%) peripheral blood mononuclear cell specimens. Seven cord blood specimens from neonates born to mothers who were positive for peripheral blood mononuclear cell human papillomavirus type 16 deoxyribonucleic acid were found to contain human papillomavirus type 16 deoxyribonucleic acid. One cervicovaginal and two peripheral blood mononuclear cell specimens contained human papillomavirus type 18 deoxyribonucleic acid, but none of the cord blood specimens contained human papillomavirus type 18 deoxyribonucleic acid.

CONCLUSION

These results seem to suggest possible transplacental transmission of the virus and the potential association of such transmission with the status of human papillomavirus in peripheral blood mononuclear cells.

Prenatal diagnosis of intrauterine infection with parvovirus B19 by the polymerase chain reaction technique

Human parvovirus B19 is a recently recognized cause of fetal hydrops and death. Efforts to characterize the natural history of fetal infection with this virus have been hampered by the lack of sensitive and specific tests for diagnosis in utero. Using the highly sensitive polymerase chain reaction (PCR) assay, we determined the fetal infection status in 56 pregnancies by testing amniotic fluid, fetal serum, and maternal serum for B19 DNA and antibodies. Factors associated with a high risk of B19 infection were fetal disease, exposure to persons with erythema infectiosum, or signs or symptoms of acute B19 infection. Fifteen women (27%) were B19 IgM-positive, a status suggesting recent infection; the positivity of all of the corresponding fetal specimens for B19 DNA in the PCR was indicative of fetal infection. In four of these cases, serial ultrasonographic examinations documented spontaneous resolution of fetal hydrops. Twenty-four women (43%) were IgG-positive and IgM-negative; this pattern suggested prior infection. The PCR gave positive results, consistent with recent maternal infection, in four of these cases. Seventeen women (30%) were IgG-negative and IgM-negative, a pattern suggesting no prior infection; the PCR results in four cases were indicative of a possible early maternal infection or a possible atypical immune response. The PCR is a sensitive and rapid method for the diagnosis of intrauterine infection with human parvovirus B19 and promises to facilitate studies of the natural history and treatment of this infection.

Antibodies to seven rotavirus serotypes in cord sera, maternal sera, and colostrum of German women

Forty percent of colostrum samples from German women showed neutralizing antibody titers of greater than or equal to 50 to rotavirus (RV) serotypes 1, 3, 4, and 6. Antibody to serotypes 2, 8, and 9 was less prevalent. Titers are, however, too low to indicate an important effect of colostrum on the RV vaccine take rate. On the other hand, about 50% of the cord serum samples showed high neutralizing-antibody titers to serotypes 1, 3, and 4, which could interfere with the take rate of RV vaccines based on these serotypes in very young infants.

Identification of Treponema pallidum in amniotic fluid and fetal blood from pregnancies complicated by congenital syphilis

Two pregnant women with secondary syphilis underwent amniocentesis and evaluation for fetal syphilis. In both cases, motile spirochetes, typical of Treponema pallidum, were observed during dark-field microscopic examination of the amniotic fluid. The presence of T pallidum was confirmed by antitreponemal monoclonal antibody immunofluorescence assays and by rabbit infectivity tests using the amniotic fluid. In the first case, an infant at 35 weeks' gestation delivered within 24 hours of amniocentesis had hepatosplenomegaly, osteochondritis, and neurosyphilis. In the second case, a fetus at 24 weeks' gestation was hydropic and a fetal blood sample showed anemia, thrombocytopenia, and elevated liver enzymes. Fetal syphilis was confirmed by rabbit infectivity testing using fetal blood obtained by funipuncture. This is the first report of the diagnosis of fetal syphilis by funipuncture and confirmation of the presence of virulent T pallidum in the blood of a human fetus. The mother was treated for secondary syphilis, but the infant had residual signs of congenital infection at birth 14 weeks later. Neonatal serum from the first case and fetal serum from the second case showed specific immunoglobulin M reactivity with the 47-kd antigen of T pallidum by Western blot assays. A new wild-type strain of T pallidum, designated DAL-1, was isolated from the amniotic fluid of the first case and is available for future studies. We conclude that the presence of T pallidum in amniotic fluid or fetal blood indicates fetal-placental infection. Further investigation is necessary to determine the pathogenesis of amniotic fluid infection and its role in the prenatal diagnosis of congenital syphilis.

[Prenatal diagnosis of measles infection by transabdominal puncture of the umbilical vein]

Prenatal diagnosis of fetal rubella infection was reported. Maternal infection took place at the 13th week of gestation. Percutaneous umbilical fetal blood sampling was performed at the 22nd week of gestation. 1:400 titre of rubella specific immunoglobulin in fetal sera confirmed the rubella infection. A normal baby was born by cesarean section at term and subsequent ophthalmologic, cardiologic, audiologic follow-up have not revealed any alteration in infant's development. Clinical management of fetal rubella infection was discussed.

Detection of HTLV-I antigen in peripheral and cord blood lymphocytes from carrier mothers

Vertical transmission of human T-cell lymphotropic virus type-I (HTLV-I) from an antibody-positive carrier mother to her infant has been reported, but it is not clear when and by what route such transmission occurs. Peripheral blood and cord blood lymphocytes from 40 antibody-positive carrier mothers were cultured for 2 months and HTLV-I antigen was sought by indirect immunofluorescence. Viral antigen was detected in 28 (70%) samples of peripheral blood lymphocytes and in 2 of cord blood lymphocytes, both from mothers positive for antigen in peripheral blood. From these data it is estimated that transplacental infection occurs at a rate of about 7%.