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N B Isada

Publications and source records attributed to N B Isada.

At least 19 recordsLinked to original sources
PubMed1997

Sex chromosome markers: characterization using fluorescence in situ hybridization and review of the literature.

Fluorescence in situ hybridization (FISH) using biotin labeled X- and Y-chromosome DNA probes was utilized in the analysis of 23 sex chromosome-derived markers. Specimens were obtained through prenatal diagnosis, because of a presumptive diagnosis of Ullrich-Turner syndrome, mental retardation, and minor anomalies or ambiguous genitalia; three were spontaneous abortuses. Twelve markers were derived from the X chromosome and eleven from the Y chromosome; this demonstrates successfully the value and necessity of FISH utilizing DNA probes in the identification of sex chromosome markers. Both fresh and older slides, some of which had been previously G-banded, were used in these determinations. We have also reviewed the literature on sex chromosome markers identified using FISH.

Adolescent↗
PubMed1996

Modified stylet technique for tenting of amniotic membranes.

A modified amniocentesis technique can reduce the failure rate in cases of tenting of the membranes. Failure to aspirate amniotic fluid (AF) because of amniotic membrane tenting may persist after advancement and rotation of the needle. In such cases, the membranes may be pierced by using a stylet that is longer than the length of the needle. With the needle in the middle of a suitable AF pocket, the stylet of the needle is replaced with a longer stylet. Under real-time ultrasonographic guidance, the tip of the stylet is then rapidly advanced 5-10 mm beyond the tip of the needle. During genetic amniocentesis, we have used the longer stylet technique to pierce tented membranes without complications in 21 of 22 cases.

Amniocentesis↗
PubMed1996

Hyperemesis gravidarum. Effects on fetal outcome.

OBJECTIVE: To study perinatal outcomes in pregnancies complicated by hyperemesis gravidarum (HG) as compared to controls. STUDY DESIGN: Between 1984 and 1991, 138 patients were diagnosed with HG according to Fairweather's criteria. Subjects were stratified into groups of mild and severe HG according to the presence of at least one of the following criteria: ketonuria, increased blood urea nitrogen and hematocrit, and/or abnormal electrolytes. All patients without HG on whom records were available and who delivered during the study period were included as controls. Multiple gestations and stillbirths were excluded from the analysis. Student's t test and X2 were used for statistical analysis. RESULTS: Demographic data were not significantly different between the groups. Forty patients were diagnosed as having mild HG and 98 patients as having severe; 12,335 patients were defined as controls. Mean fetal birth weights were 3,110, 3,093, and 3,160 g in the mild, severe and control groups, respectively. The incidence of congenital anomalies was 2.5%, 2.0% and 1.6%, respectively. The incidence of prematurity was 17.5%, 11.2% and 10.7% in mild and severe HG and controls, respectively. None of the outcome variables for mild or severe HG were significantly different as compared to the controls. Differences in other neonatal outcomes, including frequency of five-minute Apgar score < 7 and neonatal intensive care unit admissions, were not significantly different between the three groups. CONCLUSION: In contrast to previous reports, this study demonstrated that fetuses of gravidas admitted for HG are not at increased risk of growth retardation, congenital anomalies or prematurity. No beneficial effect on pregnancy outcome was detected.

Adult↗
PubMed1994

Fluorescent in situ hybridization utilization for high-risk prenatal diagnosis: a trade-off among speed, expense, and inherent limitations of chromosome-specific probes.

OBJECTIVE: The development of fluorescent in situ hybridization chromosome-specific probes has allowed the use of new fetal tissue collection techniques, such as fetal cells in maternal blood and coelocentesis--both of which, with current techniques, cannot generate complete karyotypes. We evaluated chromosome-specific probes for additional potential limitations in the setting of a high-risk prenatal diagnosis center. STUDY DESIGN: The last 24 months of fetal karyotypes from our prenatal cytogenetics laboratory were analyzed for those abnormalities that should be detectable by chromosome-specific probes and those that would likely be missed. RESULTS: In 6006 karyotypes 207 (3.4%) abnormalities were found, of which 104 were common trisomies, 12 triploidies, and 19 monosomies that would have been detected with current probe combinations (13, 18, 21, X, and Y) (135/207, 65.2%). Seventy-two abnormalities (35%) represented other trisomies (16/207, 7.7% for 9, 12, 15, 16) and rearrangements (inversions, translocation markers were 56/207, 27.1%), which would have been missed. CONCLUSIONS: Use of current fluorescent in situ hybridization chromosome-specific probes protocols would have detected only 65% of chromosome abnormalities in our high-risk population. Incomplete ascertainment must be weighed against the cost and speed of fluorescent in situ hybridization chromosome-specific probes when comparing it with traditional karyotyping. Although this new technique may prove useful in low-risk screening programs (fetal cells in maternal blood), its current use in high-risk populations should be questioned until its sensitivity is expanded to identify more subtle and less common chromosomal abnormalities.

Chromosome Aberrations↗
PubMed1994

Risk of anomalies as a function of level of elevated maternal serum alpha-fetoprotein.

OBJECTIVE: Most neural tube defects risks are not actual but mathematical extrapolations. We sought to evaluate this risk and to compare actual performance. STUDY DESIGN: This was a retrospective study of a referral population with elevated maternal serum alpha-fetoprotein results between 1987 and 1992. Ultrasonography results, delivery records, and autopsy results were compared with entry levels of maternal serum alpha-fetoprotein, and the percentage of fetal anomalies detected in this study was evaluated. RESULTS: A total of 773 patients with elevated maternal serum alpha-fetoprotein levels were evaluated. There was a progressive increase in the incidence of anomalies as a direct function of the level of the maternal serum AFP, varying from 3.4% at a level of 2.5 to 40.3% at a level > 7.0. CONCLUSION: Data from this study support the correlation of maternal serum AFP levels with the risk of neural tube defect and ventral wall defects.

Congenital Abnormalities↗
PubMed1994

Epidemic syphilis: maternal factors associated with congenital infection.

OBJECTIVE: Little is known about which cases of maternal syphilis will affect the newborn. Because of the current epidemic of syphilis in pregnancy in our city, we sought to identify risk factors during pregnancy associated with congenital infection. STUDY DESIGN: We reviewed 253 cases of maternal syphilis prospectively identified over a 1-year period. On the basis of neonatal diagnosis, these data were divided into two groups, those without evidence of presumptive congenital syphilis and those with evidence of presumptive congenital syphilis. Presumptive congenital syphilis was defined according to the Centers for Disease Control and Prevention surveillance case definition. Cases with bloody spinal taps and cases of suspected congenital syphilis that did not meet these criteria were excluded. Venereal Disease Research Laboratory titers are given as the inverse of the geometric mean. RESULTS: Venereal Disease Research Laboratory titer at time of diagnosis and unknown duration of disease were risk factors for congenital syphilis. There was a significantly decreased rate of congenital syphilis with single-dose therapy if disease length was < 1 year (p < 0.005). Unknown duration of disease was associated with 67.9% and 48.6% rates of congenital syphilis with one- and three-dose therapy respectively. There was a 28% incidence of preterm birth. CONCLUSION: Our study suggests an alarming rate of failure of current therapy to prevent congenital syphilis. Venereal Disease Research Laboratory titer at time of diagnosis and unknown duration of disease are risk factors for congenital syphilis. The high rate of presumptive congenital syphilis in the unknown duration group indicates that identification before or earlier in pregnancy will be necessary to prevent devastating consequences for the neonate.

Adult↗
PubMed1994

In utero surgical treatment of fetal obstructive uropathy: a new comprehensive approach to identify appropriate candidates for vesicoamniotic shunt therapy.

OBJECTIVES: We present a new approach to prenatal evaluation and prediction of renal function and long-term outcomes for fetuses considered candidates for in utero surgery. STUDY DESIGN: A review of 34 cases of obstructive uropathies was made, with analysis of our approach to prenatal evaluation, the predictive value of urinary electrolytes and protein analysis in identifying renal dysplasia, and the outcomes of cases with and without in utero surgical intervention. RESULTS: Ten of 11 pregnancies that were terminated had dysplasia; one female had cloacal dysgenesis. In three of eight unshunted cases megacystis resolved after vesicocentesis. Eight of 15 shunted fetuses survived. Of those predicted to have good postnatal outcome, six of six demonstrated good postnatal renal function. Of those predicted to have poor outcomes, two of two had poor postnatal renal function and dysplasia. Seven of 15 shunted fetuses died, four of four predicted to have dysplasia were confirmed, and three died of nonrenal causes. CONCLUSIONS: Our prenatal approach successfully differentiated fetuses with underlying renal dysplasia from those without irreversible damage who subsequently benefited from in utero vesicoamniotic shunt placement.

Congenital Abnormalities↗
PubMed1994

Gastroschisis: can antenatal ultrasound predict infant outcomes?

OBJECTIVE: To test previously proposed but unproven antenatal ultrasound prognostic criteria in fetal gastroschisis. METHODS: Thirty consecutive gastroschisis-affected pregnancies and their outcomes were reviewed retrospectively. Data were tabulated by review of antenatal ultrasound videotapes, with blinded comparison to indicators of short- and long-term infant outcomes obtained from the medical records. Criteria of previous reports were applied to these data, focusing on their ability to prognosticate effectively. RESULTS: Applying a criterion of 10 mm bowel dilatation proved minimally useful in prognosticating infant outcomes. However, a stricter 17-mm criterion for clinically important bowel dilatation provided prognostic information, with remarkable improvement in specificity (75 versus 37%) and positive predictive value (55 versus 37%) for infant morbidity, with comparatively little loss of sensitivity (71 versus 85%). CONCLUSIONS: Bowel dilated more than 17 mm on antenatal ultrasound appears to be associated with increased short- and long-term infant morbidity. Whether this finding warrants obstetric intervention in the preterm gastroschisis-affected pregnancy with substantial bowel dilatation remains to be determined.

Congenital Abnormalities↗
PubMed1994

Maternal neurosurgical shunts and pregnancy outcome.

OBJECTIVE: To assess pregnancy outcome in women with ventriculoperitoneal or lumboperitoneal shunts. METHODS: Charts were reviewed retrospectively for mothers with ventriculoperitoneal or lumboperitoneal shunts delivered at Hutzel Hospital from 1976-1992. Patients were identified by cross-referencing medical records from Children's Hospital Neurosurgical Division and medical records at Hutzel Hospital during this period. RESULTS: Eight patients with 25 pregnancies were identified from 1976-1992. Indications for shunt placement were pseudotumor cerebri (four with lumboperitoneal shunts) and congenital hydrocephalus (four with ventriculoperitoneal shunts). Pregnancy outcomes were two elective abortions, five spontaneous abortions, two preterm vaginal deliveries, one mid-forceps rotation, two primary low transverse cesareans, two repeat low transverse cesareans, and 11 spontaneous vaginal deliveries. No patient received prophylactic antibiotics during labor and vaginal delivery because of the shunt. There were no shunt-related complications. CONCLUSIONS: This series doubles the number of previously reported pregnancy outcomes in women with neurosurgical shunts. Contrary to the literature suggesting cesarean delivery and prophylactic antibiotics for all patients, our experience suggests that vaginal delivery can be considered and that prophylactic antibiotics are not an absolute necessity in uncomplicated vaginal deliveries.

Adolescent↗
PubMed1993

Prenatal diagnosis of congenital diaphragmatic hernia not amenable to prenatal or neonatal repair: Brachmann-de Lange syndrome.

Brachmann-de Lange syndrome (BDLS) is a variable multiple congenital anomaly syndrome that occasionally includes congenital diaphragmatic hernia (CDH). CDH per se is commonly diagnosed antenatally and has been corrected with increasing success in utero and by neonatal repair with extracorporeal membrane oxygenation (ECMO). In utero repair requires normal karyotype as well as the absence of other lethal anomalies. Postnatal repair in combination with ECMO has resulted in improved neonatal outcome and has been recommended in all cases not having in utero repair. We describe a fetus diagnosed with a diaphragmatic hernia at 18 weeks of gestation in a woman whose only other pregnancy has been a 16 week abortus diagnosed with Fryns syndrome (FS). FS is a lethal, variable congenital anomaly syndrome that includes CDH, which is thought to contribute to the lethality of the syndrome. In utero repair was considered, but rejected because of the position of the liver and suspected FS. The patient elected to carry the pregnancy to term. Postnatal repair with ECMO was considered; however, the infant died at several hours of age because of severe pulmonary hypoplasia, being considered ineligible for ECMO. The diagnosis of BDLS was made at autopsy and suggests that the first case may, in fact, have been BDLS. In spite of recent success in the repair of CDH both in et ex utero, CDH in association with BDLS is likely lethal, and women with fetuses diagnosed antenatally with CDH and BDLS should be counseled as such.

Adult↗
PubMed1993

Skeletal histopathology in fetuses with chondroectodermal dysplasia (Ellis-van Creveld syndrome).

Chondroectodermal dysplasia (CED) is an uncommon autosomal recessive disorder and one of the short rib polydactyly syndromes (SRPS). It is characterized by acromelic and mesomelic shortness of limbs, postaxial polydactyly, small chest, ectodermal dysplasia, and in many cases, congenital heart defects. Controversy exists over possible changes in the growth plate. With the advent of ultrasonographic examination, increasing numbers of fetuses with osteochondrodysplasias are examined by pathologists. Since histopathologic examination of the skeletal system is useful in defining various osteochondrodysplasias and it has not been described in the fetus with CED, we herein describe 3 cases of fetal CED with emphasis on skeletal histopathology. All 3 pregnancies were terminated at 22-23 weeks because of ultrasonographic demonstration of short limbs and growth retardation. Radiologically, each fetus had acromelic and mesomelic shortness of long bones with smooth round metaphyses, vertically short iliac bones, short ribs and normal vertebrae. These findings are similar to those described in the larger newborn infant with CED. Histopathologically, the cartilage of the long bones showed chondrocytic disorganization in the physeal growth zone. The findings are dissimilar to those of larger infants and older children in whom chondrocytic columnization has been seen in the central physis and disorganization in peripheral physis. Furthermore, a variable degree of chondrocytic disorganization was also seen in the central physeal growth zone of vertebrae in these fetuses. Other findings noted at fetopsy were: polydactyly in all 3 cases, congenital heart defect in 2 and an abnormal frenulum in one case. The foregoing phenotypic and radiographic manifestations and skeletal histopathology help separate CED from other SRPS.

Bone and Bones↗
PubMed1993

Fetal leg and femur/foot length ratio: a marker for trisomy 21.

OBJECTIVE: Our purpose was to determine whether the femur/foot length ratio is useful in the prenatal detection of trisomy 21. STUDY DESIGN: Direct necropsy measurements were analyzed on 436 midgestational fetuses (391 normal, 45 with trisomy 21). Necropsy leg/foot length ratio versus gestational age was found to be significantly different between normal fetuses and those with trisomy 21. On the basis of the necropsy data, 345 midgestational pregnancies were evaluated ultrasonographically for femur/foot length ratio versus gestation age to identify fetuses at risk for trisomy 21. RESULTS: A leg/foot length ratio versus gestation age < or = 2.3 correctly identified 84% of fetuses with trisomy 21 between 110 to 155 days gestation age at necropsy. An ultrasonographic femur/foot length ratio versus gestational age < or = 0.9 had an 18.3 odds ratio risk for trisomy 21 in our high-risk population and correctly identified 71% of fetuses with trisomy 21 (positive predictive value 0.24, negative predictive value 0.98). CONCLUSION: The femur/foot length ratio is an additional ultrasonographic marker for identification of fetuses at increased risk for trisomy 21.

Adult↗
PubMed1993

First-trimester simple hygroma: cause and outcome.

OBJECTIVE: First-trimester fetuses with simple nuchal hygromas represent a population that is different from midgestation nuchal cystic hygroma in terms of karyotype abnormalities and long-term prognosis. STUDY DESIGN: Sixty-eight consecutive fetuses diagnosed with simple nuchal hygromas between 10 and 14 weeks' gestation were evaluated ultrasonographically and karyotyped. Those with normal chromosome complements were ultrasonographically monitored throughout the remainder of the pregnancy for resolution of their hygromas. RESULTS: Twenty-three of 27 fetuses with normal karyotypes resolved their hygromas within 4 weeks of diagnosis and were phenotypically normal at birth. Forty-one fetuses were karyotypically abnormal, with trisomy 21 being the most common abnormality. CONCLUSIONS: Fetuses with first-trimester simple nuchal hygromas are at high risk for aneuploidy and should be offered prenatal testing. Such fetuses with normal karyotypes will likely resolve their hygromas by 18 weeks' gestation, and most will be phenotypically normal at birth.

Chromosomes, Human, Pair 21↗
PubMed1993

Basic concepts in molecular (DNA) diagnosis.

There has been an explosion of new information in molecular biology that will change the ways in which we practice medicine in the future. These laboratory advances in disease detection at the DNA level are quickly finding clinical application in prenatal diagnosis. An understanding of some basic concepts of DNA laboratory techniques and their applications is increasingly important in obstetrics and gynecology today.

DNA↗