| Flap 1 |
Flap 2 |
| What is homocystinuria? |
Deficiency of cystathionine synthase, which uses up homocysteine and methionine. Causes mental retardation and vessel thrombosis. |
| What is a common cause of increased homocysteine? |
B12/folate deficiency. B12 accepts the methyl group from folate and transfers it to homocysteine to make methionine. If this transfer doesn't happen --> accumulation of homocysteine --> damage EC's --> predisposes to thromboses --> MI |
| What is Pompe's disease? |
Deficiency of a lysosomal enzyme that breaks down glycogen (lysosomal α 1,4 glucosidase) --> build up of glycogen --> cardiomegaly with early death |
| In what patient would 6-mercaptopurine not be effective? |
Lesch-Nyhan syndrome: deficiency of hypoxanthine-guanine phosphoribosyltransferase (HGPRT). Won't activate purine synthesis or 6-mercaptopurine (drug that blocks purine synthesis), which requires activation by HGPRT to become active. X-linked recessive. |
| Hirschsprung disease |
bowel obstruction due to aperistalsis (absence or destruction of ganglion cells that control peristalsis) --> enlargement of colon. Starts at the anus and progresses upward. Proximal bowel is dilated but has peristalsis. No signs of stool on rectal exa |
| Can people with Down's have children? |
Males with Down's are infertile. Females can have babies, but have 50% of having a Down's child. |
| What are the possible chromosomal sets for Turner's Syndrome? |
Nondisjunction: 45, X = 46 total. Mosaicism: 45, X OR 45, XX |
| In Turner's Syndrome, what is the growth hormone and insulin-like growth factor profile? |
Both are normal. |
| In which disease do you have XXY karyotype? |
Klinefelter's Syndrome. XXY with female secondary sex characteristics, hypogonadism (dec testosterone and inhibin, inc LH and FSH) |
| In which disease do you have XYY karyotype? |
Paternal nondisjunction -- aggressive, sometimes criminal behavior, nl gonadal fxn. |
| Karyotype of a hermaphrodite |
46,XX, but has BOTH male and female gonads |
| Decreased maternal folate levesl cause what? |
Open neural tube defects |
| What happens in testicular feminization? |
X-linked recessive disorder where there is deficiency in androgen receptors. Can't sense fetal DHT and testosterone --> no Wolffian duct development and external genitalia remain female. |
| Do those with testicular feminization have testicles? |
Yes |
| Do those with testicular feminization have Mullerian structures such as fallopian tubes, uterus, cervix, and upper vagina? |
No because sertoli cells in testicles make MIF --> apoptosis of mullerian structures |
| What is the most common systemic complication of IV drug use? |
Hep B |
| In a cocaine addict, would you expect dilated or pin pupils? |
dilated. |
| In a heroin addict, would you expect dilated or pin pupils? |
miosis. |
| Person on some drug and experience tinnitus and vertigo |
ASA |
| Person on some drug and experiences photosensitive rash |
Tetracycline |
| ASA causes what kind of acid/base disturbance? |
Mixed. Stimulation of the respiratory center --> respiratory alkalosis. ASA is an acid --> metabolic acidosis. |
| What is the most common cause of HTN in young women? |
OCPs |
| What should you think of when you see transverse bands in a patient's nails, pt is strawberry picker? |
arsenic poisoning |
| What should you think of when you see opasities on x-ray in the epiphyses of a child with failure to grow? |
Pb poisoning. Pb is the only heavy metal that can deposit in bone. |
| Child from poor neighborhood eats paint off crib or off walls. Has severe abdominal colic, cerebral edema leading to convulsions. |
Pb poisoning. Check for microcytic anemia and failure to thrive. Look for Pb in intestines. |
| Worker in automobile factory with exposure to batteries --> abdominal colic and diarrhea |
Pb poisoning. |
| Man makes alcohol in his old radiator, peripheral neuropathy |
Pb poisoning. |
| Get pottery from some other country; pottery painter dabs paint brush on tongue |
Pb poisoning. |
| Why would someone with Pb poisoning get cerebral edema? |
Pb blocks ferrochelatase --> buildup of δ-amino-lebvulinic acid (ALA) --> toxic to neurons --> increase in vessel permeability in the brain |
| How does UVB lead to skin cancer? |
Pyrimidine dimers distort the DNA helix; inactivation of TP53 suppressor gene (enable cell to move on to S phase), activation of RAS oncogene. |
| thalassemia |
defect in making globin chains |
| Von Hippel Lindau Syndrome |
Defect in VHL gene (autosomal dominant), which regulates nuclear transcription; cerebellar hemangioblastoma, retinal angioma, renal cell carcinoma (bilateral), pheochromocytoma (bilateral). Von hippo -- around the hips bilaterally: kidneys (renal CA), ad |
| Wilms tumor |
Defect in WT gene (chromosome 11), which regulates nuclear transcription; tumor of the kidneys that typically occurs in children, rarely in adults. Autosomal dominant.Highly responsive to treatment with VINCRISTINE, with about 90% of patients surviving a |
| Elevated AFP (alpha feto protein) |
Tumor marker for hepatocellular carcinoma, yolk sac tumor of ovary or testis; also elevated in open neural tube defects (triple screen for pregnant women) |
| Decreased AFP (alpha feto protein) |
Down Syndrome |
| Bence Jones protein |
Tumor marker for multiple myeloma, Waldenstrom's macroblobulinemia; the Bence Jones' protein is the light chain of the Ig. |
| CA 15-3 |
Tumor marker for Breast carcinoma |
| CA 19-9 |
Tumor marker for Pancreatic carcinoma |
| CA 125 |
Tumor marker for Surface-derived ovarian cancer |
| CEA |
Tumor marker for colorectal and pancreatic carcinoma |
| PSA |
Tumor marker for prostate carcinoma (also elevated in prostate hyperplasia) |
| If you suspect a trophoblastic tumor in a woman, what would you want to measure in her serum? |
BhCG |
| Inheritance pattern of xeroderma pigmentosum |
autosomal recessive - defect in DNA repair |
| Inheritance pattern of Fanconi anemia |
autosomal recessive - defect in DNA repair |
| Inheritance pattern of Ataxia-telangiectasia |
autosomal recessive - defect in DNA repair |
| Inheritance pattern of Bloom syndrome |
autosomal recessive - defect in DNA repair |
| GERD predisposes to which type of cancer? |
Barrett's esophagus --> distal esophageal adenocarcinoma |
| DDx for RLQ pain |
appendicitis, Crohn's dz, ectopic pregnancy, follicular cysts, cystic teratomas of the ovaries |
| Conn syndrome |
adrenal adenoma that secretes mineralocorticoids |
| What is the most common reason for a child to have a white eye reflex? |
Congenital cataracts. Can also be due to retinoblastoma or a CMV or rubella infection. |
| 52 yo woman with weight loss and epigastric distress, upper GI series --> no peristalsis in stomach --> died. Tumors in stomach and ovaries. |
Diffuse gastric adenocarcinoma (also called Linitis plastica). Diffuse infiltration of signet ring cells in lining of the stomach --> leather bottle stomach (very hard stomach with all the infiltration!) |
| Dislocated lenses, deep vein thrombosis, stroke, atherosclerosis, mental retardation. What is the diagnosis? |
Deficiency of cystathionine synthase, which uses up homocysteine and methionine. |
