Week 3 teratogens Flashcards
What congenital abnormalities does thalidomide cause?
Phocomelia (extremely shortened limbs, feet and hands arise close to the trunk); defects of the eyes, ears, heart, genitals, kidneys, digestive tract, and nervous system
At what stage of development is the fetus most at risk for thalidomide-induced abnormalities?
3-8 weeks (first trimester)
What congenital abnormalities does methotrexate cause?
Abnormalities in multiple organ systems
At what stage of development is the fetus most at risk for methotrexate-induced abnormalities?
First trimester (38% of cases)
What congenital abnormalities do ACE inhibitors cause?
Decreased renal blood flow; leads to renal failure, hypotension, anuria, skull hypoplasia
At what stage of development is the fetus most at risk for ACE inhibitor-induced abnormalities?
Second or third trimester
What is the estimated morbidity of ACE inhibitor-induced abnormalities?
Approximately 10-20%
What congenital abnormalities does lithium cause?
Ebstein’s anomaly (inferiorly displaced tricuspid valve), increased risk for any cardiac malformation, moderately increased risk for all congenital anomalies
What congenital abnormalities does isotretinoin cause?
CNS, cardiac, ear, thymic, brachial arch abnormalities; potential increased risk for SAB
By how much do anticonvulsants increase the risk for anomalies?
Up to 3x background risk, about 10%
What congenital abnormalities does phenytoin cause?
Fetal dilantin syndrome - nail hypoplasia
What congenital abnormalities do valproic acid and carbamazepine cause?
Neural tube defects
What are the signs and symptoms of fetal alcohol spectrum disorder?
Global growth deficiency, microcephaly, learning disabilities, mild/moderate intellectual disabilities, ADHD impulsivity, poor memory, conduct disorder, facial dysmorphology (“train tracking” of ears, flattened face, small upper lip); small increased risk for birth defects
What affect does prenatal ethanol exposure have on gene expression?
Changes in intracellular calcium; alters numerous signaling pathways, some specific targets include SHH, Fgf-8, Pax6
What congenital abnormalities does cocaine cause?
Pregnancy loss, abruption, intrauterine growth retardation (IUGR), microcephaly
What congenital abnormalities does tobacco cause?
Poor fetal growth, behavioral problems, IQ deficit, some congenital anomalies (evidence is all over the place)
What maternal infections are known to cause birth defects?
TORCHZ - toxoplasmosis, “other” (varicella, syphilis), rubella, cytomegalovirus, herpes, zika
What are the common clinical manifestations of TORCH infections?
Intrauterine growth restriction (IUGR), prematurity, hypo-/hyperthermia, apnea, tachypnea, problems in multiple systems
What are the clinical features of congenital rubella syndrome?
IUGR, microcephaly, cataracts, sensorineural hearing loss, chorioretinitis, meningoencephalitis, intellectual disability
What is the incidence of congenital rubella syndrome?
85% risk if mother has first trimester infection
What are the clinical features of congenital cytomegalovirus infection?
Sensorineural hearing loss, chorioretinitis, microcephaly, intellectual disability
What is the incidence of congenital cytomegalovirus infection?
1% of newborns in US, only 10% symptomatic, 5-17% of asymptomatic newborns will develop hearing loss
What are the clinical features of zika?
Severe neurological complications (microcephaly, inflammation and apoptosis of nerve cells), malformation of the eyes and ears
What congenital anomalies are associated with maternal type 1 diabetes?
Cardiac defects, sacral agenesis, neural tube defects, pregnancy loss
What congenital anomalies are associated with gestational diabetes?
Fetal macrosomnia (large), hypoglycemia after birth due to high insulin levels during development, polycythemia, hypertrophic cardiomyopathy, microcolon; most spontaneously resolve
What is the incidence of birth defects in infants born from mothers with type 1 diabetes?
Approximately 10% (IDDM in first trimester)
What congenital anomalies are associated with infants born from mothers with phenylketonuria?
Microcephaly, intellectual disability, cardiac defects, pregnancy loss; dose response to increasing Phe levels
What congenital anomalies are associated with prenatal lead and methylmercury exposure?
Neurological/CNS impairment
