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Nicholas M Fisk - One of the best experts on this subject based on the ideXlab platform.
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second trimester Echogenic Bowel and intraamniotic bleeding association between fetal Bowel Echogenicity and amniotic fluid spectrophotometry at 410 nm
American Journal of Obstetrics and Gynecology, 1996Co-Authors: Waldo Sepulveda, R Reid, P Nicolaidis, Oonagh Prendiville, Richard S Chapman, Nicholas M FiskAbstract:Abstract OBJECTIVE: Our purpose was to determine whether the presence of heme pigments in amniotic fluid is associated with the ultrasonographic findings of increased fetal Bowel Echogenicity in the second trimester. STUDY DESIGN: Spectrophotometric analysis of amniotic fluid for optical density at 410 nm was prospectively performed to study the presence of heme pigments in (1) 104 pregnancies undergoing second-trimester amniocentesis for routine cytogenetic indications and (2) in 14 pregnancies undergoing amniocentesis for prenatal karyotyping because of fetal strongly Echogenic Bowel. In the routine amniocentesis group the fetal small Bowel Echogenicity was assessed immediately before amniocentesis and classified as nonEchogenic ( n = 64), mildly Echogenic ( n = 36), or hyperEchogenic ( n = 4) with the fetal iliac wing and liver used as references. Only amniotic fluid specimens that were obtained at the first attempt and that were not blood-stained were included in this study, with the first milliliter being discarded in all samples. RESULTS: In the routine amniocentesis group abnormal amniotic fluid optical density readings were significantly more frequent in fetuses with increased Bowel Echogenicity compared with those with nonEchogenic Bowel (8/40 [20%] vs 3/64 [5%], respectively; p CONCLUSIONS: Fetal small Bowel Echogenicity is associated with the presence of heme pigments in amniotic fluid as determined by amniotic fluid optical density at 410 nm. Swallowing of amniotic fluid after intraamniotic bleeding seems implicated in the etiology of second-trimester Echogenic Bowel in both euploid and aneuploid fetuses. (AM J OBSTET GYNECOL 1996;174:839-42.)
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prevalence of cystic fibrosis mutations in pregnancies with fetal Echogenic Bowel
Obstetrics & Gynecology, 1996Co-Authors: Waldo Sepulveda, Kwok Yin Leung, Elaine M Robertson, Edward S Mayall, Nicholas M FiskAbstract:Objective To determine the prevalence of the most common cystic fibrosis mutations in pregnancies complicated by fetal Echogenic Bowel by using DNA testing. Methods Forty-five pregnancies with fetal Echogenic Bowel were studied prospectively for cystic fibrosis mutations. Using polymerase chain reaction, DNA from fetal amniocytes (n = 21), fetal blood (n = 5), or parental blood (n = 19) was amplified and tested for ΔF508, G551D, G542X, and 621 +1G→ T cystic fibrosis mutations, which account for about 85% of the mutations in the British population. In selected cases, further mutations were tested according to the parental ethnic background. Results Only one of the 26 fetuses screened was heterozygous for cystic fibrosis mutations. Among 38 parental samples screened from the remaining 19 pregnancies, cystic fibrosis mutations were detected in two cases, only one of the parents being a carrier in each case. The prevalence of cystic fibrosis carrier status in fetal and parental samples (1:26 and 1:19, respectively) is within the expected prevalence in the British population (1:25). No fetuses were affected by cystic fibrosis in this series, but five were found to have growth restriction, two trisomy 21, two congenital infection, and two Bowel obstruction. Conclusion Our results suggest that ultrasonographic detection of fetal Echogenic Bowel is not associated with an increased prevalence of cystic fibrosis mutations in pregnancies at low risk for this disease.
Frank A Chervenak - One of the best experts on this subject based on the ideXlab platform.
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factors associated with fetal demise in fetal Echogenic Bowel
American Journal of Obstetrics and Gynecology, 2001Co-Authors: Huda B Alkouatly, Stephen T Chasen, Amer K Karam, Regine Ahner, Frank A ChervenakAbstract:Abstract Objective: The purpose of this study was to determine risk factors associated with intrauterine fetal demise in fetuses with unexplained Echogenic Bowel that is diagnosed in the second trimester. Study Design: A retrospective case-control study compared fetuses with Echogenic Bowel and fetal demise with fetuses with Echogenic Bowel who were live born. Fetuses affected with cystic fibrosis, aneuploidy, or congenital infection and fetuses diagnosed with major anomalies were excluded. Variables examined in the determination of risk factors for intrauterine fetal demise included intrauterine growth restriction, oligohydramnios, elevated maternal serum alpha-fetoprotein levels, and elevated maternal serum β-hCG levels. Statistical analysis was performed with the Fisher exact test, Student t test, and logistic regression analysis. Results: One hundred fifty-six fetuses met the inclusion criteria. There were 9 cases of intrauterine fetal demise and 147 live born control fetuses. The median gestational age of intrauterine fetal demise was 22.0 weeks (range, 17-39 weeks). Intrauterine growth restriction occurred more frequently in cases of intrauterine fetal demise than in live born infants (22.2% vs 0.7%; P =.009), as did oligohydramnios (44.4% vs 2.0%; P
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the clinical significance of fetal Echogenic Bowel
American Journal of Obstetrics and Gynecology, 2001Co-Authors: Huda B Alkouatly, Stephen T Chasen, J Streltzoff, Frank A ChervenakAbstract:OBJECTIVE: The purpose of this study was to determine the incidence of cystic fibrosis, aneuploidy, and intrauterine infection with toxoplasmosis and cytomegalovirus in second-trimester fetuses with the sonographic finding of Echogenic Bowel. STUDY DESIGN: All cases of Echogenic Bowel that were diagnosed in our ultrasound unit from 1993 to 2000 were identified. Only cases in which Bowel Echogenicity was as bright as bone with no associated major fetal anomalies were included. Patients who were referred from other hospitals were excluded. Echogenicity was classified as focal or multifocal. Fetal karyotypes, cystic fibrosis carrier testing, and maternal serologic test results were determined. RESULTS: One hundred seventy-five fetuses in 171 pregnancies met inclusion criteria. Cystic fibrosis mutations were identified in 7 of 138 mothers (5%) and 9 of 86 fathers (10.5%) who were tested. Five fetuses were affected with cystic fibrosis. Fetal karyotype was obtained in 139 cases, and autosomal trisomy was diagnosed in 5 cases (3.6%). One hundred sixty-six patients were tested for toxoplasmosis, and 111 patients were tested for cytomegalovirus. There were no cases of congenital toxoplasmosis. There was maternal serologic and fetal pathologic evidence of cytomegalovirus infection in 1 case. In all cases of cystic fibrosis and aneuploidy, Echogenicity was multifocal; in the case of cytomegalovirus, Echogenicity was focal. CONCLUSION: In our population, mid-trimester fetal Echogenic Bowel was associated with a high prevalence of cystic fibrosis, aneuploidy, and cytomegalovirus (11/175 fetuses [6.3%]). This information should be considered when counseling patients after mid-trimester Echogenic Bowel is diagnosed.
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the clinical significance of isolated fetal Echogenic Bowel
Genetics in Medicine, 2000Co-Authors: Huda B Alkouatly, Stephen T Chasen, J Streltzoff, Frank A ChervenakAbstract:OBJECTIVE: To determine the incidence of aneuploidy, cystic fibrosis (CF), and intrauterine infection with toxoplasmosis and cytomegalovirus (CMV) in second-trimester fetuses with the sonographic finding of isolated Echogenic Bowel. STUDY DESIGN: All cases of Echogenic Bowel diagnosed in our ultrasound unit from 1993-1999 were reviewed. Only cases in which Echogenicity was as bright as bone were included. Cases with associated fetal anomalies diagnosed with ultrasound were excluded. Echogenicity was classified as focal or multifocal. RESULTS: Echogenic Bowel was diagnosed in 250 patients during the study period. The study is limited to the 180 patients who were receiving prenatal care at our hospital. To date, follow-up has been obtained on 104 patients with isolated fetal Echogenic Bowel. The mean gestational age at diagnosis was 18.6 ± 2.1 weeks (range 14-24 weeks) and the mean maternal age was 32.1 ± 5.9 years (range 15-47 years). CF mutations were identified in 6 of 79 (7.6%) mothers and 5 of 58 (8.6%) fathers who were tested. Follow-up is available for 5 of 8 pregnancies in which at least one parent was found to carry a CF mutation. Three fetuses were affected with CF and one was found to be a carrier. Parents of affected fetuses were not known carriers prior to the diagnosis of Echogenic Bowel. Fetal karyotype was obtained in 87 cases and autosomal trisomy was diagnosed in 3 (3.4%). One fetus was infected with CMV demonstrated by maternal serology and inclusion bodies characteristic of CMV infection in the autopsy specimen. In all cases of CF and aneuploidy, Echogenicity was multifocal; in the case of CMV, Echogenicity was focal. CONCLUSION: Serious conditions were diagnosed in 7 out of 104 patients with isolated Echogenic Bowel: cystic fibrosis 3, autosomal trisomy 3, and CMV infection 1. There was a multifocal pattern of Echogenicity in CF affected and trisomic fetuses.
Waldo Sepulveda - One of the best experts on this subject based on the ideXlab platform.
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second trimester Echogenic Bowel and intraamniotic bleeding association between fetal Bowel Echogenicity and amniotic fluid spectrophotometry at 410 nm
American Journal of Obstetrics and Gynecology, 1996Co-Authors: Waldo Sepulveda, R Reid, P Nicolaidis, Oonagh Prendiville, Richard S Chapman, Nicholas M FiskAbstract:Abstract OBJECTIVE: Our purpose was to determine whether the presence of heme pigments in amniotic fluid is associated with the ultrasonographic findings of increased fetal Bowel Echogenicity in the second trimester. STUDY DESIGN: Spectrophotometric analysis of amniotic fluid for optical density at 410 nm was prospectively performed to study the presence of heme pigments in (1) 104 pregnancies undergoing second-trimester amniocentesis for routine cytogenetic indications and (2) in 14 pregnancies undergoing amniocentesis for prenatal karyotyping because of fetal strongly Echogenic Bowel. In the routine amniocentesis group the fetal small Bowel Echogenicity was assessed immediately before amniocentesis and classified as nonEchogenic ( n = 64), mildly Echogenic ( n = 36), or hyperEchogenic ( n = 4) with the fetal iliac wing and liver used as references. Only amniotic fluid specimens that were obtained at the first attempt and that were not blood-stained were included in this study, with the first milliliter being discarded in all samples. RESULTS: In the routine amniocentesis group abnormal amniotic fluid optical density readings were significantly more frequent in fetuses with increased Bowel Echogenicity compared with those with nonEchogenic Bowel (8/40 [20%] vs 3/64 [5%], respectively; p CONCLUSIONS: Fetal small Bowel Echogenicity is associated with the presence of heme pigments in amniotic fluid as determined by amniotic fluid optical density at 410 nm. Swallowing of amniotic fluid after intraamniotic bleeding seems implicated in the etiology of second-trimester Echogenic Bowel in both euploid and aneuploid fetuses. (AM J OBSTET GYNECOL 1996;174:839-42.)
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prevalence of cystic fibrosis mutations in pregnancies with fetal Echogenic Bowel
Obstetrics & Gynecology, 1996Co-Authors: Waldo Sepulveda, Kwok Yin Leung, Elaine M Robertson, Edward S Mayall, Nicholas M FiskAbstract:Objective To determine the prevalence of the most common cystic fibrosis mutations in pregnancies complicated by fetal Echogenic Bowel by using DNA testing. Methods Forty-five pregnancies with fetal Echogenic Bowel were studied prospectively for cystic fibrosis mutations. Using polymerase chain reaction, DNA from fetal amniocytes (n = 21), fetal blood (n = 5), or parental blood (n = 19) was amplified and tested for ΔF508, G551D, G542X, and 621 +1G→ T cystic fibrosis mutations, which account for about 85% of the mutations in the British population. In selected cases, further mutations were tested according to the parental ethnic background. Results Only one of the 26 fetuses screened was heterozygous for cystic fibrosis mutations. Among 38 parental samples screened from the remaining 19 pregnancies, cystic fibrosis mutations were detected in two cases, only one of the parents being a carrier in each case. The prevalence of cystic fibrosis carrier status in fetal and parental samples (1:26 and 1:19, respectively) is within the expected prevalence in the British population (1:25). No fetuses were affected by cystic fibrosis in this series, but five were found to have growth restriction, two trisomy 21, two congenital infection, and two Bowel obstruction. Conclusion Our results suggest that ultrasonographic detection of fetal Echogenic Bowel is not associated with an increased prevalence of cystic fibrosis mutations in pregnancies at low risk for this disease.
Wayne W Grody - One of the best experts on this subject based on the ideXlab platform.
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Bayesian analysis for cystic fibrosis risks in prenatal and carrier screening
Genetics in Medicine, 2004Co-Authors: Shuji Ogino, Robert B Wilson, Bert Gold, Pamela Hawley, Wayne W GrodyAbstract:Purpose: Risk assessment is an essential component of genetic counseling and testing, and Bayesian analysis plays a central role in complex risk calculations. We previously developed generalizable Bayesian methods to calculate the autosomal recessive disease risk of a fetus when one or no mutation is detected, and another, independent risk factor is present. Our methods are particularly useful for calculating the CF disease risk for a fetus with Echogenic Bowel. In genetics practice, however, there are other scenarios for which our previous methods are inadequate. Methods and Results: We provide herein methods for calculating genetic risks in a variety of common clinical scenarios. These scenarios include the following: (1) different mutation panels that have been used for the parents and for a fetus; (2) genetic testing results available on the proband or other relatives, in addition to the consultand; (3) fetal ultrasound negative for Echogenic Bowel with a positive family history; and (4) a consultand with a mixed ethnic background. Conclusion: Our Bayesian methods have proven their versatility through application to many different common genetic counseling scenarios. These methods permit autosomal recessive disease and carrier probabilities to be calculated accurately, taking into account all relevant information. Our methods allow accurate genetic risk estimates for patients and their family members for CF or other autosomal recessive disorders.
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bayesian risk assessment for autosomal recessive diseases fetal Echogenic Bowel with one or no detectable cftr mutation
Journal of Medical Genetics, 2004Co-Authors: Shuji Ogino, Robert B Wilson, Wayne W GrodyAbstract:Risk assessment is an essential component of genetic counselling and testing, and Bayesian analysis plays a central role in complex risk calculations.1–3 Prenatal risk assessment for autosomal recessive diseases can be particularly complex when, for example, only one mutation is detectable in the fetus, and when mutation detection rates and disease allele frequencies vary among different ethnic groups. A classic example is the risk assessment for a fetus with Echogenic Bowel and only one detectable mutation in the cystic fibrosis transmembrane conductance regulator ( CFTR ) gene. The fetus could be affected or be a carrier on the basis of the presence of one detectable mutation. Accurate risk assessment in this scenario may be critical for parental decision making. Cystic fibrosis is the most common severe autosomal recessive disorder; it affects about one in 2500 live births and has a carrier frequency of about one in 25 among European Caucasians.4 Cystic fibrosis is caused by homozygous mutations in the CFTR gene (OMIM 602421; 219700 cystic fibrosis; CFTR mutation database (http://www.genet.sickkids.on.ca/cftr/)). More than 1000 different CFTR mutations have been reported, and the mutation frequencies vary in different ethnic groups. The ultrasound finding of Echogenic Bowel, which is present in 0.1–0.2% of all pregnancies, may result from fetal meconium ileus and can result from cystic fibrosis.5,6 The American College of Medical Genetics (ACMG) uses a panel of 25 CFTR mutations and advocates carrier screening for people with a family history of cystic fibrosis and their partners, as well as for all couples in the general population in whom the woman is pregnant or considering pregnancy.7 The clinical scenarios addressed in this paper are likely to be encountered with a high frequency. Despite the importance of accurate risk assessments in these scenarios, generalisable approaches to such risk assessments are …
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online medical genetics in practice bayesian risk assessment for autosomal recessive diseases fetal Echogenic Bowel with one or no detectable cftr
2004Co-Authors: Robert B Wilson, Wayne W GrodyAbstract:Prenatal riskassessment for autosomal recessive diseases can be particu-larly complex when, for example, only one mutation isdetectable in the fetus, and when mutation detection ratesand disease allele frequencies vary among different ethnicgroups. A classic example is the risk assessment for a fetuswith Echogenic Bowel and only one detectable mutation inthe cystic fibrosis transmembrane conductance regulator(CFTR) gene. The fetus could be affected or be a carrier on thebasis of the presence of one detectable mutation. Accuraterisk assessment in this scenario may be critical for parentaldecision making.Cystic fibrosis is the most common severe autosomalrecessive disorder; it affects about one in 2500 live births andhas a carrier frequency of about one in 25 among EuropeanCaucasians.
Huda B Alkouatly - One of the best experts on this subject based on the ideXlab platform.
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factors associated with fetal demise in fetal Echogenic Bowel
American Journal of Obstetrics and Gynecology, 2001Co-Authors: Huda B Alkouatly, Stephen T Chasen, Amer K Karam, Regine Ahner, Frank A ChervenakAbstract:Abstract Objective: The purpose of this study was to determine risk factors associated with intrauterine fetal demise in fetuses with unexplained Echogenic Bowel that is diagnosed in the second trimester. Study Design: A retrospective case-control study compared fetuses with Echogenic Bowel and fetal demise with fetuses with Echogenic Bowel who were live born. Fetuses affected with cystic fibrosis, aneuploidy, or congenital infection and fetuses diagnosed with major anomalies were excluded. Variables examined in the determination of risk factors for intrauterine fetal demise included intrauterine growth restriction, oligohydramnios, elevated maternal serum alpha-fetoprotein levels, and elevated maternal serum β-hCG levels. Statistical analysis was performed with the Fisher exact test, Student t test, and logistic regression analysis. Results: One hundred fifty-six fetuses met the inclusion criteria. There were 9 cases of intrauterine fetal demise and 147 live born control fetuses. The median gestational age of intrauterine fetal demise was 22.0 weeks (range, 17-39 weeks). Intrauterine growth restriction occurred more frequently in cases of intrauterine fetal demise than in live born infants (22.2% vs 0.7%; P =.009), as did oligohydramnios (44.4% vs 2.0%; P
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the clinical significance of fetal Echogenic Bowel
American Journal of Obstetrics and Gynecology, 2001Co-Authors: Huda B Alkouatly, Stephen T Chasen, J Streltzoff, Frank A ChervenakAbstract:OBJECTIVE: The purpose of this study was to determine the incidence of cystic fibrosis, aneuploidy, and intrauterine infection with toxoplasmosis and cytomegalovirus in second-trimester fetuses with the sonographic finding of Echogenic Bowel. STUDY DESIGN: All cases of Echogenic Bowel that were diagnosed in our ultrasound unit from 1993 to 2000 were identified. Only cases in which Bowel Echogenicity was as bright as bone with no associated major fetal anomalies were included. Patients who were referred from other hospitals were excluded. Echogenicity was classified as focal or multifocal. Fetal karyotypes, cystic fibrosis carrier testing, and maternal serologic test results were determined. RESULTS: One hundred seventy-five fetuses in 171 pregnancies met inclusion criteria. Cystic fibrosis mutations were identified in 7 of 138 mothers (5%) and 9 of 86 fathers (10.5%) who were tested. Five fetuses were affected with cystic fibrosis. Fetal karyotype was obtained in 139 cases, and autosomal trisomy was diagnosed in 5 cases (3.6%). One hundred sixty-six patients were tested for toxoplasmosis, and 111 patients were tested for cytomegalovirus. There were no cases of congenital toxoplasmosis. There was maternal serologic and fetal pathologic evidence of cytomegalovirus infection in 1 case. In all cases of cystic fibrosis and aneuploidy, Echogenicity was multifocal; in the case of cytomegalovirus, Echogenicity was focal. CONCLUSION: In our population, mid-trimester fetal Echogenic Bowel was associated with a high prevalence of cystic fibrosis, aneuploidy, and cytomegalovirus (11/175 fetuses [6.3%]). This information should be considered when counseling patients after mid-trimester Echogenic Bowel is diagnosed.
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the clinical significance of isolated fetal Echogenic Bowel
Genetics in Medicine, 2000Co-Authors: Huda B Alkouatly, Stephen T Chasen, J Streltzoff, Frank A ChervenakAbstract:OBJECTIVE: To determine the incidence of aneuploidy, cystic fibrosis (CF), and intrauterine infection with toxoplasmosis and cytomegalovirus (CMV) in second-trimester fetuses with the sonographic finding of isolated Echogenic Bowel. STUDY DESIGN: All cases of Echogenic Bowel diagnosed in our ultrasound unit from 1993-1999 were reviewed. Only cases in which Echogenicity was as bright as bone were included. Cases with associated fetal anomalies diagnosed with ultrasound were excluded. Echogenicity was classified as focal or multifocal. RESULTS: Echogenic Bowel was diagnosed in 250 patients during the study period. The study is limited to the 180 patients who were receiving prenatal care at our hospital. To date, follow-up has been obtained on 104 patients with isolated fetal Echogenic Bowel. The mean gestational age at diagnosis was 18.6 ± 2.1 weeks (range 14-24 weeks) and the mean maternal age was 32.1 ± 5.9 years (range 15-47 years). CF mutations were identified in 6 of 79 (7.6%) mothers and 5 of 58 (8.6%) fathers who were tested. Follow-up is available for 5 of 8 pregnancies in which at least one parent was found to carry a CF mutation. Three fetuses were affected with CF and one was found to be a carrier. Parents of affected fetuses were not known carriers prior to the diagnosis of Echogenic Bowel. Fetal karyotype was obtained in 87 cases and autosomal trisomy was diagnosed in 3 (3.4%). One fetus was infected with CMV demonstrated by maternal serology and inclusion bodies characteristic of CMV infection in the autopsy specimen. In all cases of CF and aneuploidy, Echogenicity was multifocal; in the case of CMV, Echogenicity was focal. CONCLUSION: Serious conditions were diagnosed in 7 out of 104 patients with isolated Echogenic Bowel: cystic fibrosis 3, autosomal trisomy 3, and CMV infection 1. There was a multifocal pattern of Echogenicity in CF affected and trisomic fetuses.
