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B Eiben

Publications and source records attributed to B Eiben.

At least 37 records · Page 2Linked to original sources
PubMed1994

Early amniocentesis--a cytogenetic evaluation of over 1500 cases.

We report our cytogenetic experience of 1554 early amniocenteses between weeks 11 and 14 of gestation, of which 44 per cent were performed prior to week 14. The mean culture time was 14.5 days. Karyotyping was successful in 99.7 per cent of cases. In 9.9 per cent of cases, there was pseudomosaicism with a high rate of loss of an X-chromosome and structural aberration of chromosome 1, which may be due to the Chang medium. The mosaic rate was 0.5 per cent. The overall aberration rate was 2.8 per cent. Our data confirm the reliability of early amniocentesis, which is a serious alternative to standard amniocentesis and chorionic villus sampling (CVS).

Adult↗
PubMed1994

Discrepant karyotypes after second- and third-trimester combined placentacentesis/amniocentesis.

Cytogenetic data are presented from a total of 1306 consecutive pregnancies with successful diagnosis obtained from both chorionic villi after short-time culture (CVS-SC) and amniotic fluid cell cultures (AC); samples had been taken simultaneously at combined placentacentesis (placental biopsy) and amniocentesis during the second (92.8 per cent) and third (7.2 per cent) trimesters. Concordant results were obtained in 1218 pregnancies with a normal karyotype and in 62 pregnancies with an aberrant fetal karyotype. Discrepant, i.e. false-positive and false-negative, results were found in 26 cases (2 per cent). From these data the accuracy of CVS-SC, defined as the proportion of all correct diagnoses, is calculated to be 98 per cent. Three non-mosaic and 14 mosaic false-positive results obtained after CVS-SC could not be confirmed by AC. Related to 1235 true normal fetal karyotypes, the specificity of CVS-SC, i.e. the proportion of normal karyotypes correctly diagnosed, amounts to 98.6 per cent. In nine pregnancies, an aberrant fetal karyotype detected after AC was missed by CVS-SC. The sensitivity of CVS-SC, i.e. the proportion of abnormal fetuses correctly diagnosed (62 out of 71), amounts to 87.3 per cent in our study group.

Amniocentesis↗
PubMed1993

Retrospective study of the parental origin of the extra chromosome in trisomy 18 (Edwards syndrome).

The parental origin of the extra chromosome in trisomy 18 was traced in 30 informative families using highly polymorphic (CA) repeats mapped on the long arm of chromosome 18. Proband DNA was recovered from slides of chromosome preparations in 28 cases and from paraffin-embedded tissues in two cases. The extra chromosome was found to be of maternal origin in 26 cases (86.7%), and paternal origin in 4 cases (13.3%).

Adult↗
PubMed1993

[Early amniocentesis between the 12th-14th week of pregnancy. Clinical experiences with 1,100 cases].

Information is presented on 1100 early amniocenteses between the 12th and 14th week of gestation, performed at the Evangelisches Krankenhaus Oberhausen over a two year period. In all cases, a sufficient amount of amniotic fluid was obtained. In 99.7%, the cytogenetic diagnosis was successful. In 2.6% (29 patients), an aberrant karyotype was found. The time of cultivation was in the same range as can be observed in standard amniocentesis. The AFP-median measurements correlate with other studies. The spontaneous abortion rate was 0.3%. We conclude, that early amniocentesis can be performed safely and successfully by an experienced surgeon between the 12th to 14th week of gestation.

Abortion, Spontaneous↗
PubMed1992

Genetic amniocentesis in twin pregnancies: results of a multicenter study of 529 cases.

To evaluate the risk of abortion after genetic amniocentesis in twin pregnancies, a retrospective study of 15 centers was performed. The spontaneous abortion rate up to 20 completed weeks of gestation was 2.3%; the abortion rate up to 28 completed weeks, as defined by WHO, was 3.7%. The abortion rate could not be correlated either with the number of needle insertions or with the type of marker dye used. There was also no correlation between the abortion rate and the gestational age at which amniocentesis was performed. A significant association was shown between congenital intestinal obstructions and the application of methylene blue intra-amniotically as a marker dye. Considering the increased natural loss rate in multiple gestations, amniocentesis in twin pregnancies seems to be a safe and reliable technique.

Journal Article↗
PubMed1992

Prenatal diagnosis of monosomy 18 and ring chromosome 18 mosaicism.

The case of monosomy 18/ring chromosome 18 mosaicism which was detected prenatally by amniocentesis is presented. The pregnancy was terminated in week 18. Autopsy showed complex malformation of the fetus consisting of cebocephaly, hypotelorism, microphthalmia, severe defects of brain development, and arrest of placental maturation.

Adult↗
PubMed1991

Mosaicism and accuracy of prenatal cytogenetic diagnoses after chorionic villus sampling and placental biopsies.

Discrepant chromosome findings in placenta and fetus (false negative and false positive) after chorionic villus sampling (CVS) are mainly due to confined mosaicism. Non-mosaic normal or abnormal chromosome counts after direct preparation and culture nearly always correctly reflect the fetal chromosome constitution. False-negative results have almost exclusively been restricted to cytotrophoblast cells not representing a fetal chromosome abnormality. Diagnosis of placental mosaicism definitely requires an adequate follow-up by amniocentesis, fetal blood sampling, or sonography before a pregnancy is terminated. When direct preparations and cultured cells are used for cytogenetic diagnoses and placental mosaicism is not taken as proof for a chromosomal abnormality in the fetus, CVS is an accurate diagnostic tool.

Amniocentesis↗
PubMed1991

[Clinical experience and possibilities of rapid cytogenetic diagnosis of spontaneous abortions in the routine work load of a gynecology clinic].

The practicability of rapid karyotyping of spontaneous abortions by short-term culturing of chorionic villi is demonstrated in a large clinical study. 836 samples from spontaneous abortions were karyotyped successfully. Pathological findings were found in a rate of 48.8% whereby 54% of these were observed in week 10-11 of pregnancy. With increasing maternal age, the frequency of abnormal karyotypes also increased. Most of the pathological findings were trisomies, followed by polyploidies and monosomies. Correlation between maternal age and the type of aberration was observed. Chromosomal normal abortions were dominated by 46,XX abortions. The advantage of the described method of rapid karyotyping is the fact, that by knowing the karyotype of an abortion, a suitable concept of therapy can be chosen. Furthermore, a quick diagnosis has a positive effect on the psychological state of a patient, following a spontaneous abortion.

Abortion, Spontaneous↗
PubMed1990

Simultaneous placentacentesis and amniocentesis for prenatal karyotyping: report on 250 cases.

The efficacy and risks of simultaneous transabdominal chorionic villus biopsy (placentacentesis) and amniocentesis in the second and third trimesters were evaluated in 250 singleton pregnancies. The major indications were advanced maternal age (36.0 per cent), abnormal ultrasound findings (23.2 per cent), and low maternal AFP value (17.6 per cent). Nine abnormal karyotypes were found in placental tissue (3.6 per cent). The karyotypes of placental and amniotic cells were different in three cases, including two cases of false-positive mosaicism (0.8 per cent) and one case of a false-negative result (0.4 per cent) obtained by placental karyotyping. The problem of discrepant karyotypes in embryonic and extra-embryonic tissue does not seem to be restricted to the first trimester. The post-procedure fetal loss rate was estimated as approximately 1.8 per cent. We conclude that the procedure presented here combines the advantages of rapid karyotyping (placentacentesis) and high diagnostic reliability (amniocentesis). It does not seem to be necessary to restrict its use to late presentations and suspicious ultrasound findings.

Amniocentesis↗
PubMed1990

Cytogenetic analysis of 750 spontaneous abortions with the direct-preparation method of chorionic villi and its implications for studying genetic causes of pregnancy wastage.

Altogether, 750 cases of spontaneous abortion between the fifth and 25th week of gestation were analyzed cytogenetically by the direct-preparation method using chorionic villi. The majority of cases (68%) were derived from early abortions before the 12th week of gestation. The frequency of abnormal karyotypes was 50.1%; trisomy was predominant (62.1%), followed by triploidy (12.4%), monosomy X (10.5%), tetraploidy (9.2%), and structural chromosome anomalies (4.7%). Among trisomies, chromosomes 16 (21.8%), 22 (17.9%), and 21 (10.0%) were prevalent. The frequency of chromosomally abnormal abortions increased with maternal age but only because of an increase of trisomy. Polyploidy and monosomy X, however, decreased. Mean maternal age was significantly increased for trisomies 16, 21, and 22 and was highest for trisomies 18 and 20. The results obtained are within the range of variability reported earlier from tissue culture-type studies. A consistent feature during our study is the excess of females in chromosomally normal abortions (male:female sex ratio 0.71). According to the methodology applied, maternal cell contamination and undetected 46,XX molar samples cannot have influenced the sex ratio. However, a bias introduced by social status or maternal age cannot be excluded. With the more rapid and convenient direct preparation of chorionic villi, reliable cytogenetic data on causes of spontaneous abortions can be obtained.

Abortion, Spontaneous↗
PubMed1989

Translocation trisomy 21 in CVS not found in embryoblast: three different cell lines in CVS, amnion- and placental culture.

Chorionic villus samples from a healthy pregnant female were obtained for first-trimester prenatal diagnosis. A translocation trisomy 21 was diagnosed. A consecutive amniocentesis revealed a normal male karyotype. At term a healthy boy was born. Cytogenetic analysis from cord blood showed a regular karyotype of 46,XY, whereas in term placenta a pathological karyotype of 47,XY, +mar was found.

Adult↗
PubMed1989

The predictive value of chorionic villus histology for identifying chromosomally normal and abnormal spontaneous abortions.

To evaluate the significance of placental histology, a collaborative histological and cytogenetic study on the products of 123 spontaneous abortions of 6-19 week pregnancies was performed. From each sample, 2-3 g was dissected randomly and analysed histologically with no prior knowledge of the karyotype. Chromosomes were prepared from the remaining chorionic villi after an overnight incubation in culture medium; they were analysed by Q- or G-banding. The frequency and type of chromosome anomalies detected are comparable to those seen in other studies. Altogether, 49.6% were chromosomally abnormal, trisomies predominating (49.2%), followed by polyploidy (27.9%) and monosomy X (14.5%). The histological classification failed for technical reasons in 11 cases (8.9%). To classify the remaining cases, 18 different histological criteria were considered independently by two pathologists. A definite diagnosis was not possible for 27 abortions (22.0%), and 50 were classified as being chromosomally abnormal. This proved to be correct in 36 (72.0%), but incorrect in as many as 14 (28.0%). No evidence for an abnormal karyotype was found histologically in samples from 35 abortuses. Nevertheless, 9 of them (25.7%) had an abnormal karyotype. The predictive value of chorionic villus histology seems to be inadequate, as only 62 of 112 samples were correctly classified by histology (55.4%). The value differs little from the a priori probability of an abnormal or normal karyotype in abortuses of corresponding gestational ages.

Abortion, Spontaneous↗
PubMed1988

Chromosomal rearrangement involving chromosomes 4, 6, 11 and 11.

The case of a healthy 29-year-old woman is reported who had a history of three early spontaneous abortions. Chromosomal analysis of the mother of the patient showed a balanced karyotype of 46,XX,t(6;11) (q24; q21), whereas the chromosomes of her father were normal. The karyotype of this patient is thus a combination of a familial translocation 6;11 and a de novo translocation 4;11, which is very rare.

Adult↗
PubMed1988

Partial deletion of 4p in fetal cells not present in chorionic villi.

A case of a prenatal diagnosis at the second trimester is presented showing a normal karyotype in 12 metaphases from chorionic villi. In all cultured amniotic cells, however, and also in all fetal fibroblasts analyzed after abortion a structural anomaly (46,XY;del 4(pter----p15.2) was detected. Prenatal diagnosis was performed because of intrauterine growth retardation, cleft lip and esophagus atresia by ultrasound. The fetal stigmata are compatible with the Wolf Hirschhorn syndrome. We conclude that amniocentesis may be indicated notwithstanding a normal CV-diagnosis in those rare pregnancies with a characteristically abnormal ultrasound.

Abnormalities, Multiple↗