Flashcards in 1c.Types of errors in organ morphogenesis- Teratogens- Fetal alcohol syndrome Deck (101)
An infant is born with a malformation-type error in organ morphogenesis. During what period of development can malformations occur?
Embryonic period (weeks 3–8), intrinsic disruption
You noticed structural abnormalities in a fetus due to compression by extrinsic mechanical forces. What type of morphogenesis error is this?
Deformation, which is due to extrinsic disruption after the embryonic period
You noticed the absence of both an organ and its primordial tissue in a fetus. What type of morphogenesis error is this?
You noticed total absence of an organ in a fetus, despite the primordial tissue being present. What type of morphogenesis error is this?
You noticed incomplete development of a fetal organ in the presence of its primordial tissue. How would you categorize this observation?
A fetus has entrapment of normal tissues by amniotic bands, causing secondary breakdown. What type of error in organ morphogenesis is this?
Disruption (the example given is amniotic band syndrome)
A neonate presents with abnormalities that resulted from a single embryologic event. What type of organ morphogenesis error is this?
Sequence (an example is oligohydramnios resulting in the Potter sequence)
What embryonic process is occurring when the fetus is most susceptible to teratogens?
Between the third and eighth weeks of pregnancy (organogenesis)
A fetus is exposed to a teratogen after 8 weeks of pregnancy; will organogenesis be affected?
No (typically after 8 weeks, growth and function are affected, but not organogenesis)
A woman is exposed to alcohol during her pregnancy. What might you expect to see in her child?
Birth defects and intellectual disability—fetal alcohol syndrome is possible
A pregnant woman is taking ACE inhibitors. This can lead to damage of what organ in the fetus?
A 26-year-old woman regularly abuses a drug that her fetus may become addicted to. What three complications is she most at risk for?
This is cocaine, which can cause placental abruption, fetal addiction, and growth abnormalities
A young woman is diagnosed with clear cell carcinoma of the vagina. This cancer is associated with exposure to what teratogen in utero?
A fetus is exposed to an excess of iodine in utero. Name two teratogenic effects from this. How would iodine deficiency differ?
Congenital goiter and hypothyroidism (cretinism); iodine deficiency can cause the same two effects
A 23-year-old woman takes the acne treatment isotretinoin during pregnancy. What might result?
Multiple severe birth defects (contraception is mandatory when patients are on isotretinoin)
A boy has "flipper" limbs. Define this condition. What teratogen was he most likely exposed to in utero?
The defect is known as phocomelia or micromelia; thalidomide (limb defects with tha-limb-domide)
A 24-year-old woman refuses to quit smoking during her pregnancy. What are the consequences of tobacco use during pregnancy?
Preterm labor, intrauterine growth restriction, attention-deficit/hyperactivity disorder, placental problems, low birth weight
An infant is born with discolored teeth. What antibiotic was the fetus exposed to in utero?
A woman undergoes chemotherapy with alkylating agents during her pregnancy; what fetal abnormalities are you concerned about?
Multiple anomalies, including absence of digits
An infant is exposed to aminoglycoside antibiotics in utero. What deficit should you test for?
Deafness (cranial nerve VIII toxicity) from aminoglycocide (a mean guy hit the baby in the ear)
What birth defects might occur in a pregnant woman taking valproate?
Valproate inhibits maternal folate absorption, which may cause neural tube defects (valproate inhibits folate absorption)
A 25-year-old bipolar woman gives birth to a child with a cardiac anomaly. What medication was she taking, and what is the anomaly?
Lithium; Ebstein anomaly (atrialized right ventricle)
A baby is born with sirenomelia. The defect is associated with what maternal condition?
A mother with poorly controlled diabetes may give birth to infants with which defects?
Caudal regression syndrome (anal atresia to sirenomelia), neural tube defects, congenital heart defects
A 23-year-old woman is exposed to a teratogen that lead shielding could have blocked. What birth defects might occur?
Microcephaly and intellectual disability (caused by exposure to x-rays)
A pregnant woman takes carbamazepine as her seizure medication. What birth defects are of concern?
Facial dysmorphism, phalanx/fingernail hypoplasia, developmental delay, neural tube defects
A newborn presents with aplasia cutis congenita. What medication could cause this defect?
Methimazole (usually employed to treat hyperthyroidism)
A pregnant woman takes phenytoin. What birth defects might you expect to see in her newborn?
Fetal hydantoin syndrome (cleft palate, cardiac defects, phalanx/fingernail hypoplasia)
A woman who smoked during pregnancy has a baby with low birth weight. What is the proposed mechanism behind this?
Nicotine causes vasoconstriction, and CO causes impaired oxygen delivery—smoking is leading cause of low birth weight in developed countries