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At least 1,711 records · Page 95Linked to original sources
PubMed1998

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.

Adolescent↗
PubMed1995

Host-parasite relationship between congenital Toxoplasma infection and mouse brain: role of small vessels.

Small vessels showing inflammatory cell infiltrates were invariably observed in the vicinity of intact Toxoplasma tissue cysts within the brains of mice congenitally infected with the protozoan. Lymphocytes were observed in intimate contact with the luminal aspect of the endothelium, penetrating into the thickened basal lamina and in the perivascular area, which also contained macrophages and neutrophilic granulocytes. Rarely, lymphocytes were observed attached to the outer membrane of the host neurone which contained a Toxoplasma tissue cyst and within the inflammatory infiltrate associated with a disintegrating cyst. An hypothesis is presented which combines these morphological observations to explain the events associated with tissue cyst associated recrudescence of latent Toxoplasma infection in mouse brain.

Animals↗
PubMedDate not supplied

[Congenital hydrocephalus: clinico-pathological picture].

The authors review the main pathologic causes of congenital hydrocephalus from ischemic-vascular injuries, embryofoetal infections and dysraphisms to genetic ones. Abundant illustrations of each condition are furnished and particular attention is paid to each situation, discussing the available pathogenetic mechanisms and hypothesis. Genetic "sine causa" hydrocephalus and X-linked hydrocephalus are mainly stressed, presenting some personal data. The clinic aspects of the varying forms of hydrocephalus are continuously kept in mind and a terminal paragraph details the clinical and neuroradiological means determinant in differential diagnosis versus similar conditions such as hydranencephaly, porencephaly, aracnoid cysts, holoprosencephaly and agenesis of corpus callosum.

Brain↗
PubMedDate not supplied

TORCH serologies and specific IgM antibody determination in acquired and congenital infections.

Except for rubella testing, routine TORCH serology screens in prenatal care are of little use. Individual TORCH tests may, however, be useful based on the clinical presentation and history of the patient. The laboratory test of choice for diagnosing cytomegalovirus (CMV) and herpes simplex virus (HSV) infections is culture isolation for the virus. The presence for specific IgM antibodies in neonates is diagnostic of congenital infection. In adults, IgM antibody results should be interpreted along with the clinical findings and history of the patient. IgM antibodies may persist for months and even years and may be detected during reactivation of latent virus infections. Serum fractionation should always be performed in IgM antibody testing to avoid false positive results owing to rheumatoid factors and false negative results owing to competing levels of specific IgG antibodies. With a single serum specimen, specific IgM antibody detection may be helpful in differentiating between a recent versus past infection.

Antibodies, Viral↗
PubMed1987

Toxoplasma gondii antigens recognized by sequential samples of serum obtained from congenitally infected infants.

The Sabin-Feldman dye test, the immunoglobulin M (IgM) immunosorbent agglutination assay, and the immunoblot technique were used to study the evolution of the antibody response to Toxoplasma gondii and to examine antigens of the organism recognized by antibodies in the sera of 12 congenitally infected infants and 7 mothers. In the sera of eight infants, a significant rise was noted in the dye test titers, while the serum of only one infant demonstrated a late increase in the IgM immunosorbent agglutination assay titer. In each infant and mother, antigens with approximate masses of 35,000 and 115,000 daltons were strongly recognized by IgG antibodies. An antigen(s) with an approximate mass of 4,000 daltons was recognized by IgM antibodies in the sera of each of the mothers but was recognized by antibodies in the sera of only two of the infants.

Adult↗
PubMedDate not supplied

In utero diagnosis of congenital infections by direct fetal sampling.

Counseling for infections during pregnancy has traditionally focused on the clinical and laboratory findings of infection in the mother and the estimated risk of fetal damage associated with possible transmission of infection to the child. Now, with the use of techniques for fetal sampling, it is possible to diagnose infections of the fetus in utero and to correlate that information with the occurrence of fetal damage. The techniques that are available for sampling include amniocentesis, cordocentesis and chorionic villus sampling. The laboratory tests include: a) isolation of the organism in appropriate laboratory systems; b) detection of the DNA or RNA of the organism directly or with amplification with techniques such as PCR; c) detection of the organism by fluorescence or in situ hybridization; and d) identification of IgM or IgA fetal antibody to the organism by ELISA or similar methods. In utero infections can be documented for agents such as rubella, cytomegalovirus, parvovirus, Toxoplasma gondii and human immunodeficiency virus type 1. Further information is needed concerning the sensitivities and specificities of these methods for identifying fetal infection and predicting fetal damage.

Amniocentesis↗
PubMed2006

Performance characteristics of six IMMULITE 2000 TORCH assays.

TORCH is an acronym for Toxoplasma gondii (Toxo), other microorganisms (eg, syphilis), rubella virus (RV), cytomegalovirus (CMV), and herpes simplex virus (HSV) that are associated with congenital abnormalities from maternal infection. We evaluated linearity, imprecision, and comparison with commercially available methods of the IMMULITE 2000 (Diagnostic Products, Los Angeles, CA) Toxo IgG, Toxo IgM, RV IgG, RV IgM, CMV IgG, and HSV IgG assays. Linearity and imprecision results were acceptable. The IMMULITE 2000 assays show good concordance with other commercially available methods except for Toxo IgM and RV IgM. Toxo IgM showed better concordance with a consensus of 3 of 4 (Access, Beckman Coulter, Fullerton, CA; IMMULITE 2000; Platelia, Bio-Rad Laboratories Diagnostics Group, Redmond, WA; and Vidas, bioMerieux, Hazelwood, MO) assays than with Access alone. The RV IgM assay showed better concordance with the Zeus method than with the Diamedix method (Diamedix, Miami, FL). The IMMULITE 2000 TORCH assays studied show acceptable performance and are suitable for routine clinical use. Some commercial assays for Toxo IgM and RV IgM show rather poor concordance.

Animals↗
PubMed1975

IgG antibody suppression of the IgM antibody response to Toxoplasma gondii in newborn rabbits.

Studies were performed in an experimental rabbit model in an attempt to explore the possibility that the absence of an IgM antibody response in human infants congenitally infected with Toxoplasma may be caused by a suppressive effect of IgG antibody passively transferred from the mother. The IgM antibody response to Toxoplasma gondii infection in newborn rabbits previously injected with IgG Toxoplasma antibody was significantly suppressed as determined by an immunofluorescent antibody assay (IgM-IFA). In newborn rabbits infected with Toxoplasma, IgM-IFA antibody was first demonstrated 15 days after infection and reached a peak titer of 1:128 in two animals on days 20 and 25. In newborn rabbits injected with IgG Toxoplasma antibody and then infected with Toxoplasma, the Igm-IFA antibody and then infected with Toxoplasma, the Igm-IFA antibody response was considerably lower; the highest titer was 1:16 and occurred 25 and 30 days after infection. The results of these studies lend support to the concept that maternally transmitted IgG may suppress the IgM antibody response in the fetus and newborn infant.

Animals↗
PubMed1989

[Antigens of Toxoplasma gondii with a diagnostic and potential immunoprophylactic value: new strategies of identification].

Toxoplasma gondii is an ubiquitous protozoan parasite which induces severe pathology in in utero infected children and in immunosuppressed patients (particularly in the case of AIDS). Previous work that focused on toxoplasma somatic antigens failed to demonstrate an efficient protection against highly virulent T. gondii strains. The authors therefore first studied the role of parasite excreted-secreted (ES) antigens in the immune response. They describe here the preparation of excreted-secreted antigens in cell-free medium from tachyzoites, the intracellular proliferative stage present during acute infection. Major ES antigens have Mr of 108 K, 97 K, 86 K, 57 K, 42 K, 39 K, 28.5 K, 27 K and 21 K. The protective role of ES antigens has been demonstrated using congenitally athymic (Nu/Nu) rats that are highly sensitive to T. gondii infection (+/+ Fischer rats are resistant). The humoral and cellular components of this protection have been studied by the passive transfer either of sera or of T lymphocytes from ES-immunized +/+ Fischer rats into Nu/Nu rats. Adoptive transfers were carried out 24 hours before infection with the highly virulent T. gondii RH strain. Based on the concept of concomitant immunity, the authors have characterized antigens from tachyzoites and bradyzoites (the encysted stage persisting during chronic infection) which share common epitopes. Four tachyzoite antigens, P63, GP43, P39 and GP 28.5 have been shown by immunoprecipitation to cross-react with bradyzoite antigens. Two monoclonal antibodies raised against ES antigens permitted to demonstrate the localization of the 28.5 K and 27 K antigens inside the dense granules of tachyzoites and bradyzoites.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Management strategies for infectious diseases in pregnancy.

This review presented the clinical manifestations, diagnostic and therapeutic options, and preventive strategies for several congenital infections. The infections discussed show the spectrum of modes of vertical transmission and severity of fetal disease encountered, in addition to the successes and limitations of the current medical interventions. Further improvements in diagnostic techniques and therapies for managing the infected fetus are likely to occur during the next decade. Similarly, the widespread adaptation of new and sensitive diagnostic assays, such as the polymerase chain reaction, is likely to further improve our ability to identify infectious agents as the primary cause of certain abnormal fetal conditions. Where specific diagnostic tests and therapies have proven successful in preventing or treating fetal infections, universal screening programs should be given serious consideration. Of paramount importance, however, is the active research on the development of preventive interventions designed to prevent maternal infections and vertical transmission. Although specific immunotherapies, vaccines, and drug therapies hold great promise for controlling the spread of some infections, it cannot be overemphasized that some serious infectious complications of pregnancy may be avoided by simple preconception or early antenatal maternal counseling.

Acquired Immunodeficiency Syndrome↗
PubMed1980

Development of adverse sequelae in children born with subclinical congenital Toxoplasma infection.

Most infants born with congenital Toxoplasma infection are asymptomatic in the newborn period, and therefore their infection is not recognized. We performed follow-up evaluations on 24 such children. The mean age of these children at least examination was 8.5 years. In group I (13 children), the diagnosis was made prospectively. In group II (11 children), no symptoms or signs were noted in the newborn period and the diagnosis was made only after the first sign developed. Eighty-five percent of the children in group I and all of the children in group II have developed chorioretinitis. In group I, three children (23%) have unilateral blindness; in group II, three children (27%) and five children (45%) have unilateral and bilateral blindness, respectively. One child (8%) in group I and two children (18%) in group II developed severe, permanent neurologic sequelae after they initially presented with eye disease. Two of the children in each group are now retarded (IQ score range, 36 to 62). Six of the children in group I who were tested sequentially have had lower IQ scores (mean change from 97 to 74) on repeat tests performed an average of 5.5 years later. Less severe neurologic, intellectual, and audiologic deficits were observed in other children in each group. Treatment of some children may have had a beneficial effect on their outcome.

Adolescent↗
PubMed2006

Fetal serum beta2-microglobulin as a marker for fetal infectious diseases.

OBJECTIVES: To evaluate whether fetal serum beta2-microglobulin could be used as a marker of fetal cytomegalovirus (CMV) or toxoplasmosis infection. METHODS: beta2-microglobulin was retrospectively assayed in fetal serum collected from 64 patients with maternal infectious seroconversion (toxoplasmosis in 49 cases, CMV in 15). Using a beta2-microglobulin cutoff of 5 mg/L, infection and control groups were compared. RESULTS: Fetal serum beta2-microglobulin was >5 mg/L (5.2-13.5 mg/L) in 12 of the 13 cases with proved fetal toxoplasmosis infection, indicating 90% sensitivity. In the 39 pregnancies with maternal seroconversion but no laboratory signs of fetal infection, fetal serum beta2-microglobulin was <5 mg/L, indicating 100% specificity. Fetal serum was >5 mg/L (6.3-32 mg/L) in 14 of the 15 cases with proved fetal CMV infection, indicating 93.3% sensitivity. Specificity cannot be evaluated because maternal serum is not routinely screened for CMV during pregnancy. CONCLUSIONS: Fetal serum beta2-microglobulin is a reliable marker of fetal CMV or toxoplasmosis infection, which can be used in ambiguous situations. Because this increase is not specific, fetal serum beta2-microglobulin would potentially be raised in other fetal infections.

Biomarkers↗
PubMed1997

Accelerated detection of DNA on membranes by automated enzyme-linked immunofiltration assay.

Methods used to detect DNA after transfer to nitro-cellulose or nylon membranes are all based on slow incubation with agitation. We describe an application of the ELIFA technique (enzyme-linked immunofiltration assay) for rapid detection of DNA immobilized on a membrane by active filtration of the reagents across the membrane. The different steps (saturation, hybridization to a nonisotopically labeled probe, washing, and immunoenzymatic revelation) are automated and controlled by a microcomputer that determines the direction of flow and flow rates of the solutions through the membrane. We applied this method to the detection of Toxoplasma gondii DNA in 108 samples of amniotic fluid during antenatal tests for toxoplasmosis and compared the results with those obtained by the conventional method. In addition to a major time saving (2 h against almost 15 h), automation improves reproducibility and avoids manipulation of the membranes between the different steps, while keeping the same sensitivity and specificity as the standard method.

Amniotic Fluid↗