alpha-fetoprotein and chromosomal disorder

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when a congenital anomaly is suspected a multidisciplinary team is put together and includes these 5. ohter pediatric specialists may be the obstetrician, geneticist, perinatal and pediatric social workers, and other support personnel: perinatologis, neonatologist, sonologist, perinatal sonographer, and pediatric surgeon
once anomaly is found the ___ can work as a team to optimize clinical management, to prepare pt for possible surgery, provide the pt and fam w/ emotional support. most fetuses w/ major birth defect are delivered in _: multidisciplinary team perinatal regional centers
a genetic abnormality marked by the absence of the X or Y chromosome; not associated with advanced maternal age; affects fetal infants: turner syndrome (XO)
Turner Syndrome: 1 of __ to __ births. if fetus survives, the long-term female have immature __ development, amenorrhea, ___ neck, and short stature, poor hearing and wide spaced nipples. most spontaneously ___. moms have high _ from cystic hygromas: 5000 - 10000 sexual webbed abort MSAFP
US appearance: coarction of the aorta, hydrops, renal anomalies, tachycardia, septated cystic hygroma, IUGR, ventriculomegaly, short femure, oligohydramnios: Turner Syndrome
an ultrasound-directed biopsy of the placenta or chorionic villi (chorion frondosum). because the chorionic villi are fetal in origin, chromosomal abnormalities may be detected when cells from the villi are grown and analyzed: chorionic villi sampling
expected that AFP level in twin pregnancy is ___that of a singleton b/c 2 fetuses make twice the AFP. in multiple gestations in which there is death of co-twin (fetal papyraceous) or when 1 is acardiac twin (b/c liv still making AFP): *twice
for chorionic villi sampling (CVS)patients are ___ or older, or have had a previous child with chromosomal abnormality. the risk of fetal loss from procedure is __ to __ %.: 35 1-3
complications of this are limb reduction defects, transcervical approach can cause infection, spontaneous fetal loss, cramping, vaginal bleeding, PROM, and Rh senstitization: chorionic villi sampling
CVS is performed _or _. us done before procedure and aids by: determine the relationship b/w the __ of the ut & cx and path of the catheter; asses the fetus in terms of life, normal _, and age; identify ut _ or anything that interferes w/ catheter: transcervically or transabdominally lie morphology masses
TV CVS is performed in the ___ position. guiding stylet is initially introduced to check ut and placental position, afterward a flexible catheter is then introduced and directed into the placenta, in which the placental cells are aspirated thru catheter: dorsolithotomy position
the transabdominal CVS entails using a special apparatus attached to the ___ to permit adequate suction to withdraw the villi. this special apparatus attached permits adequate suction to withdraw the villi. performed in a similar manner to ___: needle hub amniocentesis
was first used as a techniqe to relieve polydramnios, stuck twin syndrome by transferring amniotic fluid from one fetus to another, predict Rh isoimmunization, and document fetal lung maturity: amniocentesis
this is a common reason for performing amniocentesis because they are at greater risk for having chromosomal anomaly: advanced maternal age (35 or older)
indications other than advanced maternal age for amniocentesis procedure are pts. with a previous child that has chromosomal anomaly, fetus is known to have anomaly, a history of an unexplained abnormal ___ level or abnormal __ test: AFP triple screen/quad test
risk factors that can occur is slight chance of miscarriage if performed <15 wks, can't detect all defects, premature separation of the placenta, PROM, Rh sensitization, premature labor, fetal or maternal bleeding, and fetal death: amniocentesis
amniocentesis for genetic reasons is ideally performed at __ to __ wks. gestation. it may be done as early as __ weeks but may lead to the development of fetal scoliosis or clubfoot secondary to reduced amount of amniotic fluid. it takes __ weeks to get: 15-18 weeks 12 weeks 2 weeks
amniocentesis should include a ___ to exclude anomalies and targeted areas of anatomy should be assessed: hand clenching, hypoplasia pinkie, choroid plexus cyst, ventriculomegaly, thickened nuchal fold, omphalocele, spina bifida, cardiac or foot anomalies: fetal survey
us-guided amniocentesis allows continous monitoring of the needle during amniocentesis procedure. A _-_ ml of af is aspirated through a syringe connected to 20-22 needle. after procedure fetal _ is monitored: 20-30 ml (2 tbsp) cardiac
amniocentesis in multiple gestations warrants special consideration. with multiple gestations separate __ of each sac is entered. to be certain that amniotic fluid is obtained from each sac, ___ dye can be injected into the first sac as a marker: amniocentesis indigo carmine
method in which chromosomes are analyzed; permits direct vascular access to the fetus for both diagnostic and therapeutic purposes; can be done as early as 17 wks-term & results are available 48-72 hrs later compared to 2-3 wks for amniocentesis: PUBS (percutaneous umbilical blood sampling) aka cordocentesis
fetal blood is obtained through needle aspiration of the umbilical cord; this rapid assessment may be beneficial for patients with an equivocal amniocentesis result or when a fetal anomaly is detected later in pregnancy: cordocentesis aka PUBS
risk factors include fetal or maternal hemorrhage, fetal distress, trauma, infection, PROM, pre-term labor: cordocentesis
PUBS is performed ___. us guided w/ 20-22 guage needle is inserted into umb _ about __cm. from placenta ins pt. approx _-_ ml of fetal blood is drawn and immediately analyzed for fetal cells. other possible site is _ cord loop: transab vein 1 1-4 ml free
found in fetal blood; produced by yolk sac in 1st trimester then later by GI system, liver, kidneys, and spine; is the major protein in fetal serum and is produced by the yolk sac in early gestation and later by the fetal liver: alpha feto-protein
this protein is transported into the amniotic fluid by fetal urination and reaches maternal circulation or blood through fetal membranes; anytime an organ directly comes into contact with the amniotic fluid, it will increase (i.e. spina bifida): alpha-fetoprotein
alpha feto-protein may be measure from amniotic fluid (__) or maternal serum (___): AFAFP MSAFP
neural tube defects, such as ___ and open spina bifida are common reasons for high AFP levels. normal levels are ___. less than this or more than this is abnormal. monitoring of AFP is a screening test for neural tube defects and other conditions: anencephaly 2.5 MOM (multiples of median)
MSAFP screening detects approx __% of anencephalics and __% of open spina bifida cases when 2.6 MOM are used. other causes include chromosomal abnormalities associated with fetal anomalies or placental problems that permit the abnormal passage of AFP: 88% 79%
MSAFP levels inc w/ advancing GA and peak from __ to __ wks which is ideal sampling time. AFAFP however, __ w/ GA. b/c AFP levels vary w/ GA, if fetus is older or younger than expected, AFP levels will be reported as inc or dec: 15-18 decreases
patau syndrome: 1 in _ births. extra chromo on _. extremely severe and consists of many anomalies many of which involve ___. severe retardation and ___ if do live. most die w/i hrs or _ of delivery, _% die w/i 1st mo: *5000 *13 *brain *seizures *weeks *80%
low ___ levels have been found with chromo abn such as trisomy 21, 18, and 13. other causes include wrong EDC (fetus younger than expected), fetal death (before it comes in contact with af), molars, and miscarriage: AFP
Quad results: trisomy 21 causes these 4. trisomy 18 causes these 3. open neural tube defect causes this 1.: trisomy 21: increase hCG and Inhibin A, decrease in AFP and Estriol Trisomy 18: decrease in hCG, estriol, and AFP. Open Neural tube defect (encephalocele, encephaly, spina bifida) causes twice increase in hCG
is used to detect open neural tube defect(especially spinal defects). after 20 weeks gestation this test is preferred because AFP is no longer sensitive: Acetylcholinesterase
used in early second trimester (15-20 weeks); this blood test improves the detection for trisomy 21 over MSAFP testing alone; tend to have false positive results a lot though: triple screen/quad screen test (AFP, hCG, dimeric inhibin A, unconjugated estriol)
the risk of neural tube defect of chromosomal problem is calculated for each mother. a patient may elect to undergo ultrasound with or without ___ based on the risk for chromosomal or neural tube defects. can opt for quad instead: amniocentesis
a normal karyotype consists of 46 chromosomes, 22 pairs of ___ and a pair of ___ chromosomes. ___ is an abnormality of the number of chromosomes. one of the most common aneuploid conditions is down sydrome, in which an indiv has an extra chromosome 21: autosomes sex aneuploidy
the cause of trisomy is usually ___. the cause is unknown although there is a strong association with maternal age. a chromosomal disorder is caused by too much or too little chromosomal material. can be dominant, recessive, or x-linked: nondisjunction
is a condition caused by a single defective gene; it is usually inherited from one parent who is also affected but may arise as a new mutation (spontaneous gene change). carries a 50% chance that fetus will have condition: autosomal dominant disorder
is caused by a pair of defective genes, one inherited from each parent. with each pregnancy, the parents have a 25% chance of having a fetus with this disorder: autosomal recessive disorder
are inherited by boys from their mothers. mothers don't have disease but are carriers. affected males do not transmit the disorder to their sons but all of their daughters will be carriers.: x-linked disorder
in x-linked disorder the sons of female carriers will have 50% of being _ and daughters will have 50% chance of being _: *affected *carriers
is an alternative test used to obtain a fetal karyotype by the culturing of fetal cells, similar to amniocentesis. advantage of it is that it's performed early in pregnancy, results are available w/i 1 wk and earlier results allows more options for parent: chorionic villi sampling
low IQ, moderate mental and physical delays. surgery is indicated if heart or GI defects are present. prognosis for survival depends on associated anomalies, with heart anomalies a major cause of mortality in infancy: down's sydrome
us appearance: nuchal fold, clinodactyly of the fifth finger(curved pinky), sandal foot, shortened femurs, duodenal atresia, macroglossia, shortened ear length, heart defects (AVSD), echogenic intracardiac focus, mild pyelectasis, echogenic bowel, flatten: down's syndrome
edwards syndrome: severe; is the second most common chromosomal trisomy, occurring in __ of ___ live births. this karyotype demonstrates an extra chromosome __. severe retardation and __% die within first year: 3 of 10000 18 90%
us: agenesis of cc, cho plex cyst, clefts, NTD, clenched hands, overlapping fingers,clubfoot, diaphr hernia, IUGR, micrognathia, rocker-bottom feet, strawberry shaped skull, IUGR, hydramnios, bowel omphaloceles, hydrocephalus, SUA, NIH, microcephaly: edwards syndrome
after PUBS procedure the tech watches the sample site for possible __: hemmorhage
three things with meckel-gruber syndrome: polydactyly, polycystic kidney, encephalocele
us appearance: holoprosencephaly, microcephaly, hypoteloris, bilateral cleft lip and palate, cardiac defect (coarctation of aorta), tachycardia, omphalocele, nose with single or no nostrils, postaxial polydactyl, rockerbottom foot, talipes: patau syndrome
is the result of a complete extra set of chromosomes; often occurs as a result of an ova being fertilized by two sperm, lethal condition, those surving gestation period dying shortly after birth.: triploidy
triploidy is estimated to occur in approximately _% of conceptions, although most fetuses spontaneously abort in the first trimester. only 1 in 5000 continue to 16-20 weeks gestation.: 1%
us appearance: cardiac defects, renal anomalies, omphalocele, neural tube defect, hypertelorism, cleft palate and lip, micrognathia, bradycardia, cryptorchidism (undescended testes), ambiguous genitalia, , syndactyly, and talipes, severe IUGR, SUA, oligo: triploidy
down's sydrome: is one of the most common chromosomal disorders occurring in 1 in __ births. characterized by an extra chromosome on ___. there is an assoc with advanced maternal age; however this anomaly may affect infants born to women of all ages: *660 *21
High MSAFP result in higher infant _: deaths

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Number of cards 55

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