Chapter 6 Q&A Flashcards
- 4 yo girl presents for PE; small head circumference, thin upper lip, low-bridge nose; mild mental retardation; parents state she is often emotional; what defects account for findings?
Alcohol abuse (fetal alcohol syndrome with growth retardation, CNS dysfunction, facial dysmorphology)
- 12 mo boy goes to ER and there is recent fracture of right ulna and healing fractures; blue sclerae; patient has mutation with which proteins?
Collagen (osteogenesis imperfecta, or brittle bone disease; the fragility of bone due to type I collagen synthesis affected)
- 28 yo woman has stillborn with neural tube defect; defect caused by error of morphogenesis that occurred at which stage of development?
20-40 days (dysfunction of the neural tube to close around day 23-26 of gestation)
- 20 yo man has numerous pigmented patches and pedunculated skin tumors on chest; benign neoplasm from Schwann cells; parents don’t have signs; what is the mutation for?
GTPase activating protein: neurofibromatosis type 1 characterized by disfiguring neurofibromas, areas of dark pigmentation of skin, pigmented lesions of the iris; the GTPases inactivate ras protein
- Patient with pigmented patches is at increased risk of developing which neoplasm?
Neurofibrosarcoma (a complication of neurofibromatosis type 1)
- 25 yo pregnant woman, 16 weeks gestation; US shows 3 cm neural tube defect in thoracic spine; what would screening test measure for in the serum?
Alpha-fetoprotein (AFP): will enable detection of all anencephalic features
- 25 yo man presents as tall, long fingers; later has dissecting aortic aneurysm; what mutation is here?
Fibrillin: missense mutation in gene for fibrillin leads to Marfan’s
- What is pattern of inheritance with Marfan’s?
Autosomal dominant
- 12 mo boy shows progressive weakness, mental deterioration, loss of vision; labs show decreased hexosaminidase A; child becomes blind and dies at 3 years of age; what is the path?
Accumulation of unmetabolized substrate
- Parents of kid with hexosaminidase A deficiency have four sons, two daughters, how many of their children expected to be asymptomatic?
3 (Tay-Sachs is autosomal recessive, so half expected to be asymptomatic)
- 4 yo boy has pneumonia and respiratory distress; bowel movements are greasy and have pungent odor; sweat-chloride test positive; why the steatorrhea?
Lack of pancreatic enzyme secretion (CF characterized by chronic pulmonary disease, deficient exocrine pancreatic function, and other complications of inspissated mucus in number of organs)
- For 4 yo boy with pneumonia and respiratory distress, what mutations are expected?
Membrane ion channel (Cl)
- 10 yo child presents with xanthomas on extensor surfaces of forearms; labs show cholesterol of 820 mg/dL; child’s mother and maternal grandfather with elevated serum cholesterol; where is the mutation?
LDL receptor
- 10 mo boy is fair skinned, blond hair; has mousy odor; inborn error of aa metabolism; to prevent mental retardation, what aa’s should be lacking?
Phenylalanine (PKU with autosomal recessive disease and mental deterioration)
- What is the path for the 10 mo fair skinned kid?
Accumulation of unmetabolized substrate
- 4 yo boy with pliable skin; bruises easily; joints hyperextended; deficiency of lysyl hydroxylase; what is the abnormal cell/tissue component?
Collagen fibers: Ehler Danlos (autosomal dominant, type IV)
- 25 yo woman with recurrent bone pain, increasing abdo girth; massive hepatosplenomegaly; radiolucent bone defects; large cells with fibrillar appearance reminscent of wrinkled tissue paper; where is the mutation?
Glucosidase (Gaucher disease, with Gaucher cells that have lipid-laden macrophages seen in red pulp of spleen, liver sinusoids, lymph nodes, lungs, and bone marrow)
- How do you get hepatosplenomegaly, bone pain in 25 yo woman?
Accumulation of unmetabolized substrate
- Neonate with severe motor dysfunction of lower extermities; vertebral bodies in lumbar region lack posterior arches; space under membrane has tissue with meninges and spinal cord; what can reduce incidence of neural tube defects?
Folic acid
- Parents of infant with cleft lip and palate; what can cause this error of morphogenesis?
Structural chromosomal abnormality (multifactorial inheritance, teratogens also causes of the cleft lip and palate)
- 4 yo boy has weakness in pelvic and shoulder girdles and calf muscle enlarged; CK levels elevated; foci of muscle fiber necrosis, myophagocytosis, regenerating fibers, fibrosis; where would there be alterations of the primary transcript?
Dystrophin (DMD, a severe X0linked condition with degeneration of the muscles)
- What can cause patient death from DMD?
Cardiomyopathy
- 22 yo man complains about inability to conceive child; patient is tall, gynecomastia and testicular atrophy; incrased levels of FSH; chromosomal abnormality?
Meiotic nondisjunction (Klinefelter syndrom, or testicular dysgenesis, usually involving one extra X chromosome, ie XXY)
- 35 yo pregnant woman has baby prematurely at 28 weeks gestation; neonate becomes SOB, with intercostal retraction and nasal flaring during respiration; dies of respiratory insufficiency and intraventricular hemorrhage; what is the eosinophilic material?
Fibrin (respiratory distress syndrom and deficiency of surfactant; collapse of alveoli)
- If neonate with RSD had survived, which would have led to anoxia and acidosis?
Necrotizing enterocolitis: most common acquired gastrointestinal emergency in newborns and thought to be related to ischemia of intestinal mucosa
- 16 yo girl is not menstruating; patient short, thick-webbed neck; widely spaced nipples and poor breast development; if caused by nondisjunction during mitosis of somatic cell, what is the karyotype?
45,X/46,XX: woman with Turner syndrome having mosaics rather than lacking an entire X chromosome
- 34 yo woman has female neonate with generalized edema and jaundice; CBC shows hemolytic anemia; Rh-incompatibility seen; which crossing leads to anasarca and jaundice in neonate?
IgG
- Parents of 2 yo boy with hyposadias (urethra opens on ventral aspect of penis); what pattern of inheritance?
Multifactorial:
- 42 yo woman gives birth to neonate with multiple congenital abnormalities: flat facial profile, slanted eyes, epicanthal folds, Brushfield spots, short nose, short neck, dysplastic ears, clinodactyly, large protruding tongue, heart murmur; cause?
Nondisjunction: trisomy 21/Down syndrome
- In adulthood, patient with Down syndrome has what changes?
Alzheimer disease
- 50 yo man with history of type 2 DM asks about inheritance pattern?
Multifactorial
- 25 yo man with autism and mental retardation history; has coarse facial features, increased head circumference, macro-orchidism; maternal uncle affected; fragile X syndrome rendered; cause?
Expansion of trinucleotide repeat
- 28 yo man presents to ER after experience crushing substernal chest pain; acute MI; later dies of cardiac arrhythmia; how?
Familial hypercholesterolemia (leading to accelerated atherosclerosis; due to mutations of gene encoding LDL receptor)
- 5 yo boy with maculopapular rash; rash affects palsm and soles; cracks and fissures around mouth and anus; interstitial keratitis; mild hepatosplenomegaly; anterior tibial bones with outward curvature; cause?
Syphilis: TORCH (toxoplasma, rubella, cytomegalovirus, herples, others, including congential syphilis); notice the rash early on
- 3 yo boy dies in auto accident; right lung shrunken, right main stem bronchus ends in nondescript tissue with rudimentary ducts and CT; error?
Aplasia: absence of organ coupled with persistence of the organ anlage or a rudiment
- Mother of newborn boy sees him vomit every feeding; esophagus almost completely occluded; why?
Atresia
- 87 yo woman dies in sleep: pancreatic tissue seen in wall of lower esophagus; why?
Choristomas: minute or microscopic aggregates of normal tissue in aberrant locations
Hamartomas: focal, benign overgrowths of one or more of the mature cellular elements of a normal tissue
Hemangiomas: most frequently encountered tumors in childhood
- 30 yo pregnant woman says two of three kids with yellow jaundice at birth; mother blood type O, Rh neg, husband blood type A, Rh positive; what was most likely used as indicator of fetal lung maturity?
Lecithin: made by type II pneumocytes; check to see that ratio is above 2:1 relative to sphingomyelin to see if they survive without respiratory distress syndrome
- That 30 yo pregnant woman has kid with severe generalized edema; baby dies even with transfusions; why the anasarca?
Erythroblastosis fetalis (CHF): hemolytic disease of newborn caused by maternal Ab’s against fetal erythrocytes
- An 18 yo woman gives male neonate; baby with cephalohematoma and also subperiosteal hemorrhage over calvarial bones; what is outcome of this tough delivery and labor?
Spontaneous resolution
- 42 yo woman in third pregnancy has female neonate at 30 weeks gestation; baby with jaundice within 2 days; unconjugated serum bilirubin 15 mg/dL; what is most serious complication of untreated hyperbilirubinemia in this neonate?
Encephalopathy (Kernicterus)
- 27 yo woman presents for pregnancy test; what is consequence of toxic exposure to conceptus during early development (heavy drinking)?
Embryonic lethality
