Mononuclear cell subpopulations in preterm and full-term neonates: independent effects of gestational age, neonatal infection, maternal pre-eclampsia, maternal betamethason therapy, and mode of delivery

Blood samples from 29 preterm (24-32 weeks of gestation) and 21 full-term (37-42 weeks of gestation) neonates were analysed for surface markers of lymphocyte subtypes and macrophages, and the effects of gestational age, neonatal infection, maternal pre-eclampsia, maternal betamethason therapy and mode of delivery were assessed with multiple regression analysis. Gestational age alone had few independent effects (increase in CD3+, CD8+CD45RA+, and CD11alpha+ cells, and decrease in CD14+, HLA-DR- cells) during the third trimester on the proportions of the immune cell subtypes studied. Neonatal infection and mother's pre-eclampsia had the broadest and very opposite kinds of effects on the profile of immune cells in the blood. Infection of the neonate increased the proportions of several 'immature' cells (CD11alpha-CD20+, CD40+CD19-, and CD14+HLA-DR-), whereas mother's pre-eclampsia decreased the proportions of naive cell types (CD4+CD8+, CD5+CD19+). In addition, neonatal infection increased the proportion of T cells (CD3+, CD3+CD25+, and CD4+/CD8+ ratio, and CD45RA+ cells), while maternal pre-eclampsia had a decreasing effect on the proportion of CD4+ cells, CD4+/CD8+ ratio, and proportions of CD11alpha+, CD14+ and CD14+HLA-DR+ cells. Maternal betamethason therapy increased the proportion of T cells (CD3+) and macrophages (CD14+, CD14+HLA-DR+), but decreased the proportion of natural killer (NK) cells. Caesarean section was associated with a decrease in the proportion of CD14+ cells. We conclude that the 'normal range' of proportions of different mononuclear cells is wide during the last trimester; further, the effect of gestational age on these proportions is more limited than the effects of other neonatal and even maternal factors.

Fetal blood sampling--indication-related losses

The aim of this study, was to determine the fetal loss rate after fetal blood sampling (FBS) in relation to the indication. In total, 1981 FBS procedures (1878 pregnancies) were included, of which 117 were performed for the detection of congenital infection (group 1), 1437 for the detection of haemoglobinopathy (group 2), 233 for prenatal diagnosis with normal ultrasound findings (group 3), 121 for rapid karyotyping in cases with abnormal sonographic findings (group 4) and 73 for severe growth retardation (group 5). All the procedures were performed with a free-hand technique under continuous ultrasound guidance. Pregnancy losses occurring within two weeks of FBS were considered procedure-related losses. 343 pregnancies were terminated. Of the remaining 1535 continuing pregnancies, 73 (4.8 per cent) were lost, of which 39 (2.5 per cent) were lost within two weeks of the procedure. The procedure-related losses were 3 in 103 (2.9 per cent), 17 in 1090 (1.6 per cent), 2 in 191 (1 per cent), 11 in 84 (13.1 per cent) and 6 in 67 (8.9 per cent) in groups 1, 2, 3, 4 and 5, respectively. The differences in procedural loss between the five groups were highly significant, suggesting that the method entails a much higher risk when the fetus is structurally abnormal, or severely growth retarded. Patients should therefore be counselled before the procedure accordingly.

Stillbirth evaluation: what tests are needed?

OBJECTIVE

We sought to investigate what aspects of the stillbirth evaluation are considered to be essential and what tests can potentially be eliminated.

STUDY DESIGN

A retrospective analysis of 745 stillbirths occurring from January 1990 to December 1994 was conducted. A stillbirth was defined by an estimated gestational age >20 weeks' gestational age or fetal weight >500 gm. We attempted to arrive at an apparent cause for each stillbirth after evaluation of genetic or chromosomal abnormalities, obstetric history, maternal medical illnesses, laboratory tests, autopsy findings, and placental pathologic conditions.

RESULTS

We found that the most important aspects of stillbirth evaluation were placental pathologic conditions and autopsy. When the placenta was examined, a significant abnormality was detected in 30% (160 of 529) of the cases. When autopsy was performed, only 31% of fetal deaths (142 of 462) were unexplained; however, when no autopsy was performed, 44% (125 of 283) were unexplained (p = 0.0002). The following laboratory evaluations that were routinely performed were found to yield little definitive information: antinuclear antibody testing, Kleihauer-Betke test, and screening for congenital infections (toxoplasmosis, other viruses, rubella, cytomegalovirus, and herpes simplex virus). Overall, 36% (267 of 745) of stillbirths still remained unexplained despite a thorough evaluation in most cases.

CONCLUSION

The causes of stillbirth are many and varied, with a large proportion having no obvious cause. As this study demonstrates, certain laboratory tests can be eliminated in the workup of fetal death. In the evaluation of stillbirth a complete systematic method that incorporates placental pathologic conditions, as well as autopsy findings, should prove to be beneficial.

The autosomal recessive congenital intrauterine infection-like syndrome of microcephaly, intracranial calcification, and CNS disease: report of another Bedouin family

We describe a Bedouin family with the rare autosomal recessive infection-like syndrome of microcephaly, intracranial calcification and CNS disease that has so far been documented in only eight families including one from Kuwait. In the present family, the female proband had congenital microbrachycephaly, hypertonia, early-onset tonic-clonic seizures, a palpable liver and mild pulmonary stenosis. Follow-up examination of the girl identified delayed developmental milestones while head CT scan revealed partial agenesis of the corpus callosum, brain atrophy, dilated ventricles and scattered calcific foci in the caudate nuclei, the thalami, and the periventricular white matter. The possibility of intrauterine TORCH infection was excluded by the negative results of repeated immunovirology study and by the failure to recover viral inclusions in urine cultures. The proband had three apparently affected cousins with spasticity and CT findings of microcephaly and intracranial calcification. Other previously documented cases with the congenital intrauterine infection-like syndrome are reviewed.

The diagnosis of congenital infections: contemporary strategies

Congenital infections remain an important source of neurologic, ophthalmologic, and audiologic disability for thousands of children throughout the world. This review summarizes the clinical features and describes contemporary approaches to the microbiologic diagnosis of congenital infections. In particular, this review emphasizes the important roles that molecular methods, especially the polymerase chain reaction, have in detecting the many infectious agents capable of damaging the developing nervous system.

Timely diagnosis of congenital infections

The acronym TORCH has served to increase awareness of congenital infections; however, this collective term suggests that the clinical manifestations of congenital infections are not distinguishable by pathogen. Although some clinical features may be common to several of these infections, a congenital infection caused by one pathogen generally can be distinguished from infection caused by another pathogen on a clinical basis. Pediatricians need to be aware of the prominent features of each congenital infection rather than to consider them collectively. This article focuses on the prominent features of the more common congenital infections, suggests a specific diagnostic approach, and reviews the available therapeutic strategies.

Management strategies for congenital infections

Information on congenital infection is continuously expanding. New diagnostic techniques are making significant contributions to the prenatal diagnosis of several fetal infections. In this review we highlight some of the most recent advances in the diagnosis and management of the most common fetal infections, those caused by cytomegalovirus, human immunodeficiency virus 1, Toxoplasma, varicella-zoster virus, and parvovirus B19.

Epidemiology of neonatal infections

Neonatal infections can be considered in three groups, those acquired antenatally, perinatally and nosocomially. For many years it has been recognized that antenatal infections may cause death or serious fetal damage, but only recently have the more subtle features of antenatal infection been recognized. These include particularly the ability of some (such as toxoplasmosis) to produce disease many years later. Perinatal infection is often the result of maternal carriage of organisms, usually asymptomatically, and a variety of treatment approaches including immunotherapy (for hepatitis B) and antibacterial prophylaxis (for chlamydia) are being used to reduce the short- and long-term morbidity associated with this route of neonatal infection. Nosocomial infection in the neonatal nursery, and particularly in the neonatal intensive care unit may again lead to longer term problems in the infant, and organisms such as staphylococci or salmonella acquired during neonatal life may cause invasive disease weeks or even months later. The prevention of nosocomial infection will depend on the synthesis of a variety of approaches to reduce the number and spread of organisms in the environment of the vulnerable neonate.

Can expression of CD45RO, a T-cell surface molecule, be used to detect congenital infection?

Exclusion or confirmation of congenital infection can be difficult in newborn infants. The presence of an infective organism in a fetus leads to activation of fetal T lymphocytes. We have examined expression of isoforms of a T-cell surface molecule, CD45RO, in 119 infants, 8 of whom had an intrauterine infection diagnosed antenatally. CD45RO was expressed on fewer than 10% of T cells in control infants and on more than 17% of T cells from infants with known infection (p < 0.006). This method allows screening of infants for infection by a range of organisms as a cause of their infection.

Problems with serum IgM as a screening test for congenital infection

The purpose of this study was to determine the usefulness of the total serum IgM level as a screening test for congenital infection in asymptomatic or mildly symptomatic infants. A retrospective medical record review was performed on 168 infants in whom the serum IgM was measured as a screen for congenital infection. The indications for testing, the yield of testing, and the adequacy of follow-up of abnormal values were examined. Only one infant was diagnosed with a congenital infection which was not specifically suspected prior to screening; this was a case of congenital cytomegalovirus (CMV). Inappropriate screening was frequently performed in infants in whom indications for specific evaluation were present. Appropriate follow-up testing was performed in only 30% (seven of 23) of the infants with elevated serum IgM who received their pediatric care at our institution. Because of the low yield (< 1%) and lack of follow-up shown in this study, as well as poor sensitivity, serum IgM was not a useful screening test for congenital infection in our institution.

What can be learned from cordocentesis?

Cordocentesis is a well-accepted procedure that is widely practiced by experienced perinatologists. Its facile and safe access to the fetal circulation has broadened the spectrum of congenital disorders diagnosed prenatally. Some fetal disease states can now be identified and treated earlier, directly, more quickly, and more effectively than before, resulting in improved patient care. Although cordocentesis has been embraced by the perinatal community, it is, by definition, a technique of obtaining a fetal blood sample. A prerequisite for the procedure to exert its full impact on perinatal care is a highly capable clinical laboratory. The facility must be aware of the commonly requested fetal serologic, hematologic, and serum chemistry studies, as well as their normal values. Efforts must be made to perform fetal blood studies rapidly and reliably on small specimens. Laboratory personnel should be familiar with the indications and pitfalls of these tests and those that are best referred to a specialty laboratory. A general understanding of the perinatologist's needs and concerns will lead to a cooperative working relationship between clinician and laboratory. In this manner, we will truly discover what can be learned from cordocentesis.

[Pre- and perinatal infections with sexually transmissible microorganisms]

The sexually transmissible pathogenic microorganisms, which are also capable of initiating pre- or perinatal infections, include Neisseria gonorrhoeae, Treponema pallidum, Chlamydia trachomatis serovars D through K, group B streptococci, urogenital mycoplasmas, herpes simplex viruses types I and II, cytomegalovirus, hepatitis B virus, human immunodeficiency viruses, human papillomaviruses, Candida spp. and Trichomonas vaginalis. With special emphasis on paediatric and neonatological aspects, brief discussions of the following topics are presented: the epidemiology of these agents, the diseases they can induce in pregnancy, the mode of infection of and the diseases in the fetus and neonate, the preventive measures, the diagnosis and therapy.