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D L Economides

Publications and source records attributed to D L Economides.

At least 55 records · Page 3Linked to original sources
PubMed1998

The role of ultrasonographic markers for trisomy 21 in women with positive serum biochemistry.

OBJECTIVE: To assess the value of particular markers detected by second trimester ultrasound examination among those women whose fetuses were shown to be at increased risk of Down's syndrome on the basis of biochemical screening. DESIGN: A retrospective study of 459 pregnancies. SETTING: Fetal Medicine Unit, Royal Free Hospital. PARTICIPANTS: Four hundred and fifty-nine pregnant women, including four twin pregnancies, registered at the Royal Free Hospital, who were considered screen positive (risk > 1:250) based on the results of mid-trimester biochemical markers (maternal serum free beta human chorionic gonadotrophin and alpha-fetoprotein). MAIN OUTCOME MEASURES: The ultrasound markers that were examined included structural defects, shortened femur length, echogenic bowel, dilation of the renal pelvis and choroid plexus cysts. The likelihood ratios for trisomy 21 for each of these markers were calculated. RESULTS: Of the 463 fetuses which were screen positive, 449 (97%) had a normal karyotype detected by amniocentesis (n = 344) or postnatal follow up (n = 105). Fourteen fetuses had an abnormal karyotype including 11 (2.4%) with trisomy 21. Ultrasound markers were found in 9/11 (81.8%) fetuses with trisomy 21, compared with 44/449 (9.8%) with a normal karyotype. Detection of one or more ultrasonographic markers in a screen positive pregnancy increased the risk of trisomy 21 by a likelihood ratio of 8.4, and the absence of such markers decreased the risk by a likelihood ratio of 0.2. The risk was considerably increased when the presence of two or markers were detected (likelihood ratio 41). In trisomy 21 fetuses the two most commonly detected markers, shortened femur and dilation of the renal pelvis, had likelihood ratios of 49.3 and 20.5, respectively. Choroid plexus cysts were detected in 27 of the normal karyotypic fetuses compared with none of those with trisomy 21. CONCLUSION: The presence or absence of abnormal ultrasonographic markers can significantly change the risk of Down's syndrome among pregnant women already found to have abnormal serum biochemistry. This data may be useful in counselling such women.

Chromosome Aberrations↗
PubMed1998

Pregnancy in women with von Willebrand's disease or factor XI deficiency.

OBJECTIVE: To assess the obstetric outcome in women with von Willebrand's disease or factor XI deficiency. SETTING: Haemophilia Centre and Haemostasis Unit, The Royal Free Hospital. POPULATION: Women with von Willebrand's disease (n = 31) and with factor XI deficiency (n = 11) registered at the Royal Free Hospital Haemophilia Centre who had had a pregnancy within the previous 17 years (1980-1996), including 84 in women with von Willebrand's disease and 28 in women with factor XI deficiency. METHODS: Women were interviewed and details of the obstetric history were obtained. The records of the Haemophilia Centre and the women's maternity records were also reviewed. RESULTS: Threatened miscarriage occurred in 33% and 14% of pregnancies with von Willebrand's disease and factor XI deficiency, respectively. Excluding recurrent miscarriages, 14/68 (21%) of pregnancies with von Willebrand's disease and one pregnancy with factor XI deficiency miscarried spontaneously. There was an increased incidence of primary and secondary post-abortal bleeding complications. Factor VIII and von Willebrand factor antigen and activity levels increased significantly in pregnancy in all women apart from those with severe von Willebrand's disease. Factor XI, however, did not show any significant change. No neonatal haemorrhagic complications in association with the birth process were reported, although ventouse and difficult forceps deliveries were avoided. Extensive perineal bruising and haematoma was reported in three women with von Willebrand's disease; two of these were associated with forceps delivery. The incidence of primary postpartum haemorrhage was 18.5% in von Willebrand's disease and 16% in factor XI deficiency. Blood transfusion was required in six cases of von Willebrand's disease and two cases of factor XI deficiency. Ten of fourteen instances of primary postpartum haemorrhage occurred when maternal factor levels were < 50 IU/dL with no prophylactic treatment for labour. The incidence of secondary postpartum haemorrhage was 20% in von Willebrand's disease and 24% in factor XI deficiency. None of the women who had prophylactic treatment during labour or the puerperium suffered any significant bleeding complications. There were three neonatal bleeding complications. CONCLUSION: Pregnancy, labour and the puerperium are associated with significant bleeding problems in women with von Willebrand's disease or factor XI deficiency, but these are largely preventable. Specialist obstetric care in close liaison with the haemophilia centre is essential to minimise maternal and neonatal complications.

Abortion, Spontaneous↗
PubMed1998

The effect of fetal neck position on nuchal translucency measurement.

OBJECTIVE: To determine the influence of the position of the fetal neck on nuchal translucency measurement. DESIGN: A prospective cross-sectional study. POPULATION: One hundred and ninety-six. METHODS: Nuchal translucency was measured in the mid-sagittal plane, with the fetal neck in the flexed, neutral and extended positions. Measurements were made to the nearest 0.1 mm. Statistical analysis used the paired t-test for differences between the extended and neutral positions, [delta extended nuchal translucency] and the flexed and neutral positions [delta flexed nuchal translucency]. RESULTS: The mean extended nuchal translucency was 0.62 mm greater than the mean neutral nuchal translucency value [95% confidence interval 0.53 to 0.70, T = 14.33, P < or = 0.00001]. The mean flexed nuchal translucency was 0.40 mm less than the mean neutral nuchal translucency value [95% CI 0.34 to 0.47, T = 11.99; P = < 0.00001]. The repeatability coefficient was lower in the case of neutral nuchal translucency measurements [0.48] and was higher in the other groups [extended = 1.04, flexed = 0.70]. CONCLUSION: Fetal neck position can make a significant difference to nuchal translucency measurements. Repeatability of measurements are more accurate with the fetal neck in the neutral position. These findings have important implications for clinicians using nuchal translucency to screen the general obstetric population.

Cross-Sectional Studies↗
PubMed1998

Prenatal diagnosis of autosomal dominant polycystic kidney disease (PKD1) presenting in utero and prognosis for very early onset disease.

We describe four prenatal diagnoses in a family with autosomal dominant polycystic kidney disease. Two pregnancies were terminated following the detection of enlarged echogenic fetal kidneys with cysts. Histopathological examination confirmed the diagnosis of polycystic kidney disease. Linkage to PKD1 was obtained by the analysis of DNA from relatives in three generations and from paraffin blocks and formalin fixed fetal tissues. Prenatal DNA analysis in subsequent pregnancies identified one unaffected fetus and one fetus carrying the high risk PKD1 allelle. Information on survival and subsequent outcome of PKD cases presenting in utero was requested by this family before prenatal testing was performed. Of 83 reported cases of ADPKD presenting in utero (excluding termination of pregnancy) or in the first few months of life, 43% died before 1 year. Longitudinal follow up of 24 children in two studies showed that 67% of survivors developed hypertension, of whom three had end stage renal failure at a mean age of 3 years.

Adult↗
PubMed1998

Increased nuchal translucency and CATCH 22.

Recent developments in cytogenetics has shown that 22q11 microdeletion is related to a broad spectrum of malformations which are described under the acronym CATCH 22 (Cardiac, Abnormal faces, Thymic hypoplasia, Cleft palate, Hypocalcaemia and 22 chromosome deletion). We describe a case of a fetus with increased nuchal translucency at 12 weeks' gestation presenting with congenital cardiac defects of DiGeorge syndrome type and hypocalcaemia at birth. The neonate was also diagnosed as carrying the 22q11 microdeletion. When nuchal translucency measurement is increased, CATCH 22 spectrum of malformations should be considered and therefore a thorough karyotype analysis should be performed to exclude microdeletion of chromosome 22.

Adult↗
PubMed1997

Acceptability by patients of transvaginal sonography in the elective assessment of the first-trimester fetus.

The acceptability of transvaginal sonography (TVS) for visualization of first-trimester fetal anatomy was investigated in 160 women sequentially attending a routine dating scan clinic at 12-13 weeks' gestation. All women underwent transabdominal sonography (TAS) in the first instance to assess gestational age. Of these women, 88.1% agreed to undergo TVS. The main reasons for declining were fear of miscarriage (42.1%) and discomfort (36.8%). With TVS, 51.8% described no discomfort, 47.5% mild and 0.7% marked discomfort. Of the women who underwent TVS, 95% said that they would have no concerns about a further TVS in another pregnancy. Of those women who had previously had TVS (11.9%), all agreed to have TVS in this pregnancy and experienced significantly less concern about the procedure than did those who had never had TVS before. TAS was associated with discomfort and inconvenience only if women tried to fill their bladder prior to the scan. In conclusion, TVS is acceptable and well tolerated by an unselected pregnant population. Acceptability rates for TVS should improve as its use becomes more widespread.

Female↗
PubMed1997

The effect of nuchal translucency measurement on second-trimester biochemical screening for Down's syndrome.

In this study we examined the effect of introducing first-trimester nuchal translucency measurement on the second-trimester maternal serum screening for trisomy 21. The detection rate, false-positive rate, likelihood ratio and positive predictive value of the double marker test before and after introduction of nuchal translucency measurement were determined. The detection rate of nuchal translucency screening for trisomy 21 was 83% (5/6) with a 1.3% false-positive rate, a 63.8 likelihood ratio and a positive predictive value of 22.7%. After the introduction of nuchal translucency measurement, the likelihood ratio for a positive result and positive predictive value of the biochemical screening decreased from 9.1 to 5 and 2.7% to 0.45%, respectively. Our results show that nuchal translucency measurement is not only an effective method of first-trimester screening for Down's syndrome but also has implications for the likelihood ratio and positive predictive value of second-trimester biochemical screening. Since the biochemical test is now applied to a population with a decreased risk of trisomy 21, a positive test will be less likely to indicate Down's syndrome than when nuchal translucency measurement was not applied.

Biomarkers↗
PubMed1997

The obstetric experience of carriers of haemophilia.

OBJECTIVE: To review the obstetric problems, pregnancy outcome and management of carriers of haemophilia. DESIGN: Retrospective review of haemophilia and maternity unit records. SETTING: Haemophilia Comprehensive Care Centre. PARTICIPANTS: Thirty-two carriers of haemophilia (24 haemophilia A, eight haemophilia B) who had their obstetric care at the Royal Free Hospital over a 10-year period (1985-1995). MAIN OUTCOME MEASURES: Uptake and results of prenatal diagnosis, changes in factor levels during pregnancy, effect of knowledge of fetal gender on obstetric management and neonatal outcome, and maternal haemorrhagic complications. RESULTS: There were 82 pregnancies and 32 resulted in miscarriage or social abortion. The option of prenatal diagnosis was taken up in only 35% (17/48) of pregnancies. There were five affected male fetuses diagnosed prenatally but only three women opted for termination of the pregnancy. Knowledge of fetal gender was unavailable to the attending obstetrician in 46% (21/46) of pregnancies. A fetal scalp electrode was applied in eight, fetal blood sampling was performed in four, and ventouse delivery was conducted in one of these pregnancies. No adverse effects were reported from the first two procedures, but the ventouse delivery was associated with a huge cephalhaematoma requiring blood transfusion. On the other hand, in five cases fetal blood sampling was withheld because fetal gender was unknown. Four of the eight caesarean sections performed might have been avoided if the gender had been known. The incidence of primary and secondary postpartum haemorrhage was high, 22% (including two cases with massive haemorrhage) and 11%, respectively. CONCLUSION: Carriers of haemophilia A and B require special obstetric care with close liaison with the haemophilia centre, and management guidelines should be available and observed. Knowledge of fetal gender is very valuable for management in labour and should be determined antenatally even if the mother declines prenatal diagnosis.

Abortion, Induced↗
PubMed1997

Prenatal diagnosis of supernumerary chromosome derivative (22) due to maternal balanced translocation in association with diaphragmatic hernia: a case report.

An aneuploid fetus was detected prenatally by cordocentesis at 27 weeks' gestation following ultrasonographic diagnosis of severe fetal growth retardation and a large diaphragmatic hernia. The fetal karyotype was revealed to be 47,XX,der(22)t(11;22)(q23.3;q11.2) after parental bloods confirmed a balanced reciprocal translocation in the mother. Approximately 85 cases with an unbalanced karyotype 47,XX(or XY),+der(22),t(11;22) due to 3:1 meiotic disjunction in the parental translocation carrier have been reported in the world literature and only one of them was diagnosed prenatally. This is the first detailed case report of a supernumerary derivative (22) chromosome abnormality diagnosed prenatally in association with diaphragmatic hernia.

Adult↗
PubMed1996

Nuchal translucency measurement: training of potential examiners.

The aim of this study was to assess a training regimen for nuchal translucency measurement by transabdominal (TAS) and transvaginal sonography (TVS). After initial instruction regarding the criteria for correct nuchal translucency measurement, trainees (A and B) and an experienced examiner (C) performed nuchal translucency measurements on fetuses of 10-13 weeks' gestation, and the trainees' ability to obtain a measurement, repeatability and levels of agreement were assessed. In addition, a further experienced examiner (D) performed nuchal translucency measurements to validate the training regimen. Examiner C obtained nuchal translucency measurements in 94% by TAS, 93% by TVS and 100% by a combination of both scan modes. The repeatability coefficient was 0.40 mm and 0.24 mm for TAS and TVS, respectively. Trainees A and B were considered trained after 80 and 100 scans with TAS and TVS, respectively. They were considered trained when they could consistently obtain measurements that were of comparable repeatability and comparable levels of agreement with those of examiner C. The trainees' difficulties with TAS were in achieving satisfactory repeatability and levels of agreement, but with TVS it was ability in obtaining a measurement. We propose the training methods, standards and criteria used in this study as the basis for training sonographers in nuchal translucency measurements.

Chromosome Aberrations↗
PubMed1996

Nuchal translucency measurements: frequency distribution and changes with gestation in a general population.

OBJECTIVE: To investigate nuchal translucency variation with crown-rump length (CRL) in the first trimester in normal fetuses. DESIGN: A prospective observational study. SETTING: Department of obstetrics in a London teaching hospital. PARTICIPANTS: One thousand seven hundred and seven pregnant women (1685 singleton and 22 twin pregnancies) with chromosomally normal fetuses between 9+zero and 14+6 weeks of gestation were recruited sequentially from a dating scan clinic. Nuchal translucency was measured in 94.9% by transabdominal sonography (TAS) and by transvaginal sonography (TVS) if difficulty was encountered with TAS (5.1%). Nuchal translucency measurement was repeated in 136 fetuses: the first scan between between 9+zero-11+6 weeks and the second over 12 weeks of gestation. RESULTS: Of this general population, 4.2% had a nuchal translucency (NT) measurement > or = 2.5 mm, but this proportion varied significantly between gestational age groups (P = 0.011). The repeatability coefficients for NT measurements were 0.44 mm and 0.23 mm for TAS and TVS, respectively. The cross-sectional data demonstrate an increase in nuchal translucency measurement between 9 and 12 weeks of gestation and then a decrease at 13-14 weeks. This relation is best modelled using the quadratic equation: log10 (NT) = -1.03 + (0.0314 x CRL) - (2.20 x 10(-4) x CRL2). Longitudinal data confirmed an increase of nuchal translucency measurements with increasing gestation. CONCLUSION: Nuchal translucency measurements increase significantly with increasing gestation. The use of a single threshold nuchal translucency measurement throughout the first trimester is inappropriate. We propose reference ranges of nuchal translucency measurements with gestation, aiming to improve the performance of nuchal translucency screening for chromosomal abnormalities.

Cross-Sectional Studies↗
PubMed1995

First-trimester diagnosis of Meckel-Gruber syndrome by transabdominal sonography in a low-risk case.

Meckel-Gruber syndrome is a rare autosomal recessive disorder often resulting in neonatal death within a few hours of life. The condition is usually diagnosed ultrasonographically in the second trimester and earlier diagnosis has been mainly confined to high recurrence risk pregnancies. We describe the earliest non-invasive diagnosis of this condition at 12+2 weeks' gestation in a patient with no previous history using transabdominal ultrasound. Pregnancy termination was declined. Subsequent development of anhydramnios in the mid-trimester resulted in poor fetal visualization. We propose that first-trimester diagnosis of this condition is not only possible but preferable, as normal liquor volume facilitates visualization of fetal anatomy.

Adult↗
PubMed1995

The measurement of nuchal translucency with transabdominal and transvaginal sonography--success rates, repeatability and levels of agreement.

The objective of this prospective observational study was to assess the abilities of transabdominal sonography (TAS) and transvaginal sonography (TVS) to measure nuchal translucency (NT) and to establish the levels of agreement between the two scan mode measures. The study was carried out in the Fetal Medicine Unit and 242 pregnant women were recruited from a routine dating scan clinic. All patients underwent TAS and TVS, and two separately obtained measurements of the NT were recorded. The ability to measure NT and the repeatability and levels of agreement between the scan mode measures was assessed. A measurement of NT was obtained in 92% and 90% of fetuses using TAS and TVS, respectively, and in 100% of fetuses by combination of the scan modes. Failure to measure NT with TAS was due to inability to obtain mid-sagittal views because of unfavourable fetal lie or poor resolution, especially in patients with high body mass indexes. Although there was generally good correlation between the two scan mode measurements, a significant overmeasuring of NT was observed with TAS (mean difference +/- SD: 0.10 +/- 0.29 mm, p < 0.01). The repeatability coefficients were 0.40 mm and 0.22 mm for TAS and TVS, respectively. An examiner needs to have the ability and equipment to perform TAS and TVS to consistently measure NT. Considering the overmeasurement of NT with TAS and the improved repeatability with TVS, measurements of NT in a screening programme for chromosomal abnormalities should be by TVS, at least when a prior TAS reveals a value close to a threshold level.

Abdominal Muscles↗
PubMed1993

Anti-D concentrations in fetal and maternal serum and amniotic fluid in rhesus allo-immunised pregnancies.

OBJECTIVE: To investigate the relation between anti-D concentrations in maternal serum, fetal serum and amniotic fluid, and the development of fetal anaemia. DESIGN: Observational cross sectional and longitudinal study. SETTING: Regional referral centre. SUBJECTS: Sixty-one women undergoing fetal blood sampling at 19 to 36 weeks' gestation for fetal blood and haematocrit estimation for the management of Rh (D) allo-immunisation. Thirty-eight pregnancies (7 with an Rh (D) negative fetus) were tested only once but the rest had two to five fetal blood samplings. INTERVENTIONS: Ultrasound guided fetal blood sampling and amniocentesis, and automated analysis of anti-D antibody quantitation. RESULTS: There were strong correlations between maternal serum, fetal serum and amniotic fluid anti-D concentrations. Analyses of both longitudinal and cross sectional data demonstrated a decrease of the maternal/fetal serum anti-D ratio with gestation. In pregnancies with Rh (D) negative fetuses the maternal/fetal anti-D ratio was significantly lower (P < 0.0001) than in those with Rh (D) positive fetuses. The degree of fetal anaemia (delta haematocrit) was correlated with maternal serum and amniotic fluid anti-D concentrations (r = -0.55, n = 54, P < 0.0001; r = -0.57, n = 44, P < 0.0001, respectively) but there was a weaker correlation with fetal serum anti-D (r = 0.37, n = 54, P < 0.01). CONCLUSION: Anti-D concentrations in maternal serum, fetal serum and amniotic fluid are correlated with fetal anaemia. The decrease in maternal/fetal anti-D ratio with gestation suggests an increase in placental permeability for anti-D with advancing pregnancy.

Amniotic Fluid↗
PubMed1992

Does amniotic fluid analysis reflect acid-base balance in fetal blood?

OBJECTIVE: The purpose of the study was to examine whether the acid-base balance in amniotic fluid reflects the acid-base state in fetal blood. STUDY DESIGN: The pH, PCO2, PO2, bicarbonate, and base excess concentrations were measured in umbilical venous, umbilical arterial, and maternal venous blood and in amniotic fluid samples obtained at fetoscopy. This was performed before intraamniotic termination of 16 normal pregnancies (mean gestation 19.4 weeks), as well as in 14 red blood cell isoimmunized pregnancies (mean gestation 28.4 weeks) undergoing fetoscopy for the diagnosis and treatment of fetal anemia. RESULTS: In normal pregnancies, amniotic fluid pH and bicarbonate were significantly lower than umbilical venous and umbilical arterial blood concentrations, and this was due to the high concentration of base deficit in amniotic fluid. Whereas amniotic fluid PCO2 did correlate significantly with fetal umbilical venous PCO2 values, there was no correlation between other acid-base characteristics. CONCLUSION: Simultaneous sampling of human fetal umbilical blood and amniotic fluid under the acute conditions of this study did not show significant correlations in acid-base values.

Acid-Base Equilibrium↗