Prenatal Diagnosis PDF

PHYSIO OB LECTURER: DOC EWAN KO NA BASTA KUMUNOY HAHAHAHA PRENATAL DIAGNOSIS Higher PPV The science of identifying congenital abnormalities and...

PHYSIO OB LECTURER: DOC EWAN KO NA BASTA KUMUNOY HAHAHAHA PRENATAL DIAGNOSIS Higher PPV The science of identifying congenital abnormalities and Specific for individual aneuploidies genetic conditions in the fetus Select a screening test that will identify the higher proportion of Encompasses the diagnosis of structural malformations chromosomal abnormalities, both are comparable with specialized ultrasound, screening tests for aneuploidy, Comparable, but the carrier screening tests for genetic diseases, and diagnostic yield may be higher with Comparable tests performed on chorionic villi and amniotic fluid integrated or sequential Goal: to provide accurate information regarding short and long screening term prognosis, recurrence risk and potential therapy ANEUPLOIDY SCREENING NOT RECOMMENDED: HISTORICAL PERSPECTIVE Following diagnosis of a major fetal anomaly Brock (1972) – observed that pregnancies with fetal neural- o Do prenatal diagnosis with amniocentesis or chorionic tube defects had higher levels of alpha feto-protein in villus sampling maternal serum and amniotic fluid Not valid in the setting of an abnormality that affects the Wald (1977) - established the association of NTD and MSAFP AFP component, i.e. neural tube defect or ventral wall (Maternal Serum Alpha Feto-Protein) (tested at 16-18 defect weeks) Less accurate in twin gestations (invalid in triplet and higher-order multiples) 1980-1990s – SONOGRAPHY Advanced maternal age – amniocentesis for karyotyping SCREENING FOR ANEUPLOIDY Elevated MSAFP – Level I Sonography Should be an informed choice (-) Level I Sonography – Amniocentesis for AF-AFP and Counseling should be individualized assay for acetylcholinesterase SENSITIVITY – proportion of fetuses with a particular Level II sonography (targeted sonography) – diagnostic aneuploidy who are detected by the screening test test of choice SPECIFICITY – proportion of unaffected pregnancies with a negative screening result ANEUPLOIDY SCREENING ANEUPLOIDY - is the presence of one or more extra TYPES OF ANEUPLOIDY TESTING chromosomes (usually trisomy) or loss of a chromosome Cell-Free DNA Screening (cfDNA) (monosomy Identifies DNA fragments that are derived primarily from Trisomy 21 (50%), Trisomy 18 (15%), Trisomy 13 (5%), sex apoptotic trophoblast which are placental cells chromosomal abnormalities - 45X, 47,XXX, 47XXY, 47XYY undergoing programmed cell death (12%) Not gestational age dependent, can be performed any Risk factors: advanced maternal age > 35yo, numerical or time after 9-10 weeks structural chromosomal rearrangement, a prior pregnancy with Most commonly used to screen for autosomal trisomies autosomal trisomy or triploid (trisomy 21, 18, 13) and for 45,X (Turner syndrome) 3 types of assays: (1) whole genome sequencing, (2) 2 TYPES OF ANEUPLOIDY SCREENING TESTS chromosome selective or targeted sequencing and (3) 1. Traditional or Analyte-Based Screening analysis of single nucleotide polymorphisms a. 1st trimester aneuploidy screening Highest sensitivity and specificity of any aneuploidy b. 2nd trimester aneuploidy screening Integrated and screening test Sequential screening Positive predictive value of a positive cFDNA is provided in 2. Cell-free DNA Screening the report or may be estimated from an online calculator ANALYTE BASED-SCREENING CELL-FREE DNA SCREENING or reference table (TRADITIONAL) Maybe offered as a secondary screening test for women Frequently positive with a Specific for individual who wish to avoid amniocentesis large range of aneuploidy in women 35 y/o Other genetic syndromes where cfDNA can be used: chromosomal and older abnormalities Lower likelihood of false- trisomies 16 and 22, specific microdeletion syndromes, and positive results large copy number changes throughout the genome KUMUNOY’S IMPROPERTY 1  PHYSIO OB LECTURER: DOC EWAN KO NA BASTA KUMUNOY HAHAHAHA o American College of Obstetricians and Gynecologists NUCHAL TRANSLUCENCY (2020e) does NOT recommend cfDNA screening for The maximum thickness of the subcutaneous translucent these other conditions because screening accuracy area between the skin and the soft tissue overlying the fetal has not been validated. (the only validated for tests spine at the back of the neck are trisomy 13, 18 and 21) An increased NT thickness is not a fetal abnormality but a cfDNA SCREENING LIMITATIONS MARKER that confers increased risk 1. cfDNA analyzed is maternal and placental, results may Measured when the CRL is at 38-84mm and in sagittal not reflect the fetal DNA complement plane 2. Does not yield a result in approximately 4-8% of Normal 4 mm Kallman syndrome, chondrodysplasia punctata and 4. Echogenic fetal bowel – CMV, cystic fibrosis (maputi yung mental retardation bituka, ang normal kasi ay hypoechoic common sa trisomy 21) 5. Short femur (below 2.5%tile) & humerus ( 3 MoM, what Targeted a. 30 to 32 weeks b. 24 to 28 weeks 2nd trimester will be the next step? sonography is used c. Less than 11 weeks d. 15 to 20 weeks screening! a. Repeat the test later until it becomes as primary method Which screening test uses the combined normal to evaluated results of first and second trimester in b. Increase fluid intake and repeat the test Integrated elevated MSAFP aneuploidy detection? c. Screen for diabetes COMBINED levels a. Integrated b. Stepwise d. Ultrasonography c. Cell free DNA d. Contigent KUMUNOY’S IMPROPERTY 7  PHYSIO OB LECTURER: DOC EWAN KO NA BASTA KUMUNOY HAHAHAHA Which of the following condition will require Which condition will have a low alpha- Down’s syndrome amniocentesis? fetoprotein? Also Trisomy 18 Neural tube defect a. Oligohydramnios b. CHD a. Spina bifida b. Anencephaly c. Discordant twins d. Neural tube defect c. Gastroschisis d. Down’s syndrome Which is a LIKELY complication of At what age of gestation does serum hCG 16 weeks gestation percutaneous umbilical cord blood reach a plateau? Hemorrhage sampling? a. 16 weeks gestation b. 20 weeks gestation Huy prelims pa to + Fetal bradycardia a. Fetal death b. Tachycardia c. 24 weeks gestation d. 12 weeks gestation alam mo na to c. Hemorrhage d. Infection What is an abnormal nuchal translucency? All of the above Which of the following condition is an Trisomy 18 a. more than 1cm but less than 2 cms (correction) indication for Chorionic villi sampling? Specimen is sent for b. more than 2cm but less than 3 cms Basta normal NT chromosomal microarray a. Neural tube defect b. Trisomy 18 c. less than 1cm. 35 years old needle d. Fetal position screening? Risk for fetal trisomy Which of the following statements is TRUE in A. Accurate gestational dating increases with screening for aneuploidy? B. Age >35 years old maternal age after A. A negative screening test result always C. Multiple congenital anomalies 35 years old rules out aneuploidy. Not recommended if D. Singleton pregnancy B. All screening tests are accurate even for major fetal anomaly Why is nuchal translucency a better Can provide multifetal pregnancy. is diagnosed by screening test for multifetal gestations than information to both C. Not recommended if major fetal anomaly ultrasound. serum testing? fetuses is diagnosed by ultrasound. A. It can be performed anytime NT evaluation may be helpful in multifetal D. Screening accuracy of cell free DNA is B. More accurate in diagnosing aneuploidy gestations because 100%. than serum testing serum screening is less Which of the following condition will benefit accurate, may not be C. Can provide information to both fetuses available, and cannot from cord blood sampling analysis? D. Can predict complications related to provide information RBC a. Neural tube defect chorionicity specific to each fetus. alloimmunization b. RBC alloimmunization The result of the nuchal translucency of a BLOOD c. Congenital heart disease 38year-old G1P0 is 5mm. What is the next Offer diagnostic d. Trisomy 21 BEST step in the evaluation? prenatal testing What is ideal timing for amniocentesis for A. Await the result of HCG and PAPP-A Normal NT thickness genetic diagnosis? B. Offer the sequential screening 15-20 weeks recommended at this time? Anencephaly! than 35 years at delivery a. Pregnancy associated plasma protein A A first trimester patient being screened for b. Nuchal translucency measurement Trisomy (T) showing a high beta HCG and low T 21 c. Amniocentesis Pregnancy Associated Plasma Protein-A. T18, 13 – low b-hCG, d. Maternal serum alpha fetoprotein What is the consideration? PAPP-A What is the preferred method of fetal Intravascular a.T 18 b.T 21 c.T 13 d.T 15 transfusion? transfusion Which of the following statements is TRUE Fetal transfusion usually a. Combination of intravascular/peritoneal regarding maternal obesity? 34-35 weeks b. Peritoneal transfusion a. Decreases the incidence macrosomia May result in fetal Most commonly, c. Intravascular transfusion intravascular b. May result in fetal cardiomyopathy cardiomyopathy c. Increases the risk of congenital cataract Which of the following is NOT part of the d. May result to fetal neurological defect definition of prenatal diagnosis? At what age of gestation (weeks) is the a. Identifies fetal structural congenital measurement of maternal serum alpha- malformations Prevents stillbirth fetoprotein done? 15 to 20 b. Offers screening test a.24 to 28 c.11 to 14 c. Optimizes perinatal outcome b.15 to 20 d.21 to 23 d. Prevents stillbirth Which of the following is TRUE regarding Which of the following methods of pre- trophectoderm biopsy in preimplantation implantation genetic testing will not reflect genetic diagnosis? paternal origin of the genetic disorder? a. Specimen is taken when the embryo is 3 No cells are a. Trophectoderm biopsy Polar body biopsy days old removed from the b. Blastomere biopsy b. No cells are removed from the developing developing embryo c. Chorionic villus biopsy embryo d. Polar body biopsy c. It is taken immediately after Meiosis I & II Nuchal translucency d. Puncture of the zona pellucida is needed Which of the following is an EARLY marker for Early. 1st trimester A 37 y/o G1P0 PU 18 weeks had an elevated fetal aneuploidy? screening result of maternal serum alpha-fetoprotein. a. Short femur b. Amniotic AFP Baka isagot niyo CRL Oligohydramnios c. Nuchal translucency d. CRL ha, aneuploidy ang Which of the following conditions should be Nasa mahabang tanong considered? table under ng 2nd Which of the following fetal conditions can a. Oligohydramnios trimester aneuploidy aneuploidy screening be offered? Thickened nuchal b. Gestational hypertension screening A. Anencephaly B. Multiple pregnancy fold c. Gestational diabetes d. Overestimated gestational age C. Omphaloceole D. Thickened nuchal fold KUMUNOY’S IMPROPERTY 11  PHYSIO OB LECTURER: DOC EWAN KO NA BASTA KUMUNOY HAHAHAHA Preimplantation genetic diagnosis differs Which test has the highest sensitivity and from preimplantation genetic screening in specificity to aneuploidy? Cell-free DNA which of the following? A. Analyte based B. Cell-free DNA a. Indicated for couples with history of C. Maternal serum AFP D. NT Performed for recurrent pregnancy loss Which serum marker is included in the QUAD couples with known b. Offered to all couples for in-vitro fertilization screening test? unconjugated estriol genetic disease c. Performed for couples with known genetic A. activin disease B. human placental lactogen hCG, estriol, inhibin, d. Affected embryos are always identified C. pregnancy associated plasma protein A MSAFP and discarded D. unconjugated estriol A 35 y/o G1P1 (0101) with irregular menses A35 y/o G1P0 PU 16 weeks with low maternal consulted with a positive pregnancy test. She Confirm gestational serum AFP, high HCG and high dimeric is obese, had gestational hypertension and age with ultrasound inhibin. Her first trimester screening test diabetes during her first pregnancy. What showed high risk for aneuploidy. What is the Perform should be done FIRST to help her achieve a Parang yung SGD MOST appropriate amniocentesis healthy pregnancy? lang natin to. Ano management for her at this point? a. Confirm gestational age with ultrasound un among gagawin. A. Check for nuchal translucency 15-20 weeks b. Monitor weight gain and blood pressure Di ba US muna to B. Do targeted ultrasound c. Prescribe vitamins and supplements confirm C. Perform amniocentesis d. Request for laboratory tests D. Perform chorionic villus sampling When is the BEST time to diagnose What is the interpretation if the screening test chorionicity in multiple pregnancy? showed low pregnancy associated plasma Trisomy 18 a. Before 6 weeks gestation Between 6 weeks protein (PAPP-A), low serum AFP, low HCG b. Third trimester gestation and end of and low estriol? May table to check c. Second trimester first trimester A. Spina bifida B. Trisomy 18 niyo na lang d. Between 6 weeks gestation and end of first C. Trisomy 21. D. X-linked ichthyosis trimester What is the risk of performing chorionic Fetal limb defects Which among these fetal specimens is tested Venous blood villous-sampling? Limb reduction for karyotyping in cordocentesis? Sa umbilical vein A. Fetal limb defects B. Vaginal spotting defects and a. Venous blood b. Fetal skin tinutusok yung needle C. Preterm labor D. Genetic abnormalities oromandibular limb c. Arterial blood d. Chorionic villus during cordocentesis hypogenesis What is the most common indication for fetal Which of the following conditions is 1st- Suspected fetal blood sampling? trimester screening indicated? anemia A. Suspected fetal anemia A. 30-year-old G4PO (0300) Previous child with B. Karyotyping of hemophilia Kahit ito na lang B. Husband's blood type is B (-) Edward's Syndrome itama mo C. Rule out liver abnormalities C. Previous child with Edward's Syndrome D. Compatibility with maternal antibodies D. Previous child with neural tube defect A parturient delivers and (A & C are CORRECT) Which of the following principles of 1st- has undiagnosed Sa maternal graves disease may trimester screening should be followed? Grave’s disease. Which transplacenta passage ng IgG TSH à A. Done anytime during the 1st trimester Screening test of the following is an goiter, tachy, growth restriction, B. Measurement of nuchal translucency can should be based on expected finding in the hydramnios, accelerated bone be excluded a predetermined fetus? maturation, heart failure, hydrops C. Reported as nanograms/ml and adjusted value a.Hypotonia on gestational age b.Gastroschisis Dagdag ko na rin dito D. Screening test should be based on a c.Hyperthermia Kapag naman receiving medication for predetermined value d.Microglossia graves disease si mommy may Which of the following screening tests gives a high yield for the detection of Trisomy 21? transplacental passage ng methimazole Combined 15 and A. 1st-trimester screening 2nd-trimester or propylthiouracil à fetal B. 2nd-trimester screening screening hypothyroidism C. Combined 15 and 2nd-trimester screening D. Contingent sequential screening Which of the following fetal conditions can be When is the best time to perform managed medically and prenatally? Congenital adrenal amniocentesis? A. Congenital adrenal hyperplasia 15-20 weeks hyperplasia A. 6-8 weeks. B. 10-13 weeks B. Meningocoele C. Down's syndrome C. 15-20 weeks. D. 24-28 weeks D. Turner's syndrome KUMUNOY’S IMPROPERTY 12  PHYSIO OB LECTURER: DOC EWAN KO NA BASTA KUMUNOY HAHAHAHA Twin to twin transfusion Which of the following fetal conditions can Check niyo na lang last be managed surgically prenatally? page ng trans. Andun yung fetal surgery A. Twin to twin transfusion Kapag Medical: B. Intraventricular hemorrhage arrythmia, congenital C. Pseudohermaphroditism adrenal hyperplasia, congenital cystic D. Macrocephaly adenomatoid malformation, Thyroid disease The following are conditions that can be helped by fetal surgery EXCEPT: A. Myelomeningocoele Congenital cardiac B. Sacrococcygeal teratoma anomalies C. Congenital cardiac anomalies D. Congenital diaphragmatic hernia Which of the following can diagnose aneuploidy? Chorionic villi a. Cordocentesis sampling (CVS) Cordocentesis/Fetal b. Fetal scalp sampling blood sampling – c. Chorionic villi sampling (CVS) fetal anemia d. Bilirubin on amniocentesis Which is the MOST common prenatal diagnostic procedure? a. Amniocentesis Amniocentesis b. CVS c. Fetal Blood Sampling KUMUNOY’S IMPROPERTY 13