USMLE step 1 - associations

Rx for neutropenia that causes pulmonary edema, pain, vomiting, rash

sargramostim (GM-CSF)

glucokinase defect

decreased glucose sensing --> decreased insulin secretion

hereditary angioedema

C1 esterase inhibitor deficiency (ACE inhibitors counter-indicated)

uncoordinated esophageal spasm with angina-like symptoms

diffuse esophageal spasm

non-bizarre delusion for at least one month with no other psych sx

delusional disorder

3rd pharyngeal pouch

thymus
inferior parathyroids

4th pharyngeal pouch

superior parathyroids

1st pharyngeal pouch

middle ear and auditory tube epithelium

2nd pharyngeal pouch

palatine tonsil epithelium

thymus abnormalities

myasthenia gravis

why does blood arriving at the right atrium have a slightly lower O2 content than blood in the pulmonary capillaries?

venous admixture: blood from bronchial veins returns to the right heart via the azygous, hemiazygous, and intercostal veins (although most of the blood from the bronchi is returned to the left heart)

superficial inguinal nodes

all skin from the umbilicus down, external genitalia, anus below the pectinate line

function of inhibin

negative feedback on FSH secretion from anterior pituitary

products of sertoli cells

anti-mullerian hormone
androgen binding protein
inhibin

hormone levels in klinefelter syndrome (XXY)

decreased testosterone and inhibin
increased FSH and LH

derivatives of rathke's pouch

anterior pituitary
cranipharyngioma (calcified cystic tumor)

two lab values that, when elevated, contribute to insulin resistance

free fatty acids
triglycerides

raphe nuclei

serotonin

nucleus ceruleus

norepinephrine

nucleus basalis of Meynert

acetylcholine

red nucleus

motor coordination of upper extremities

cause of increased end-diastolic sarcomere length in the myocardium

increased preload (e.g. isotonic saline infusion)

thromboembolisms, marfanoid habitus, improvement with vitamin B6

homocystinuria

aneurysm of either of these arteries can cause CN III palsy by compressing the nerve as it exits the midbrain

posterior cerebral artery
superior cerebellar artery

derivatives of metanephric mesoderm

bowman's space
glomerulus
nephron

derivatives of ureteric bud

collecting duct
calyces
renal pelvis
ureters

part of nephron impermeable to water

ascending loop

17-hydroxycorticosteroids in urine

11beta hydroxylase inhibition (hypertension, low aldosterone, low cortisol, increased sex hormones)

elevated actylcholinesterase in amniotic fluid

neural tube defect (also: elevated alpha-fetoprotein)

amino acid that is a nitrogen source for urea in the urea cycle

aspartate

embryologic origin of CNV maxillary and mandibular branches

1st branchial arch

1st pharyngeal pouch derivatives

middle ear
eustachian tubes (mesoderm)
mastoid air cells

2nd pharyngeal pouch derivatives

epithelial lining of the palatine tonsil

3rd pharyngeal pouch derivatives

thymus (endoderm)
inferior parathyroids (endoderm)

4th pharyngeal pouch derivatives

superior parathyroids (endoderm)

5th pharyngeal pouch derivatives

parafollicular cells of medullary thyroid

pygmalion bias

researcher's belief in treatment changes outcome of treatment

hawthorne bias

group being studied changes behavior d/t knowledge of being studied

risk factors for HPV

multiple partners (most important)
smoking
early intercourse
HIV

enzymes important for carcinoma to invade, become metastatic

metalloproteinases (collagenase, hydrolase)

increased homovanillic acid in urine

adrenal medulla tumor (neuroblastoma, pheochromocytoma)

cancers caused by smoking

laryngeal (squamous cell)
lung (squamous and small cell)
kidney (renal cell)
bladder (transitional cell)

neoplasm with inc EPO

renal cell
hepatocellular
pheochromocytoma
hemangioblastoma

neoplasm with inc ACTH

small cell lung cancer

neoplasm with inc PTH-related peptide

squamous cell lung ca
renal cell ca
breast ca

neoplasm with inc ADH

small cell lung ca
intracranial

neoplasm with muscular weakness (Lambert-Eaton syndrome)

small cell lung ca
thymoma

immature teratoma

aggressive, males, fetal demise

mature teratoma

benign, females, ovarian cyst

struma ovarii

teratoma containing mature thyroid tissue, causing sx of hyperthyroidism

bone mets

prostate (blastic), breast (blastic or lytic) > lung (lytic) > testes, thyroid

causes of elevated alpha-fetoprotein

neural tube defect
hepatocellular carcinoma
non-seminoma germ cell tumor (yolk sac or mixed embryonal)

biceps reflex nerve root

C5/6

triceps reflex nerve root

C7

patellar reflex nerve root

L4

achilles reflex nerve root

S1

deficiency of this hormone causes decreased bone density

estrogen

pupillary reflex (afferent/efferent)

II / III

corneal reflex (afferent/efferent)

V-1(nasociliary) / VII(temporal)

lacrimation reflex (afferent/efferent)

V-1 / VII (V-1 lesion does not preclude emotional tears)

jaw jerk reflex (afferent/efferent)

V-3 / V-3

gag reflex (afferent/efferent)

IX / IX, X

normal serum calcium and phosphate, with increased alk phos

Paget's

increased serum calcium and alk phos with decreased phosphate

hyperparathyroidism (osteitis fibrosis cystica, "brown tumors")

microspherocytes

autoimmune hemolytic anemia

extravascular hemolysis

hereditary spherocytosis
pyruvate kinase deficiency
sickle cell anemia
IgG and IgM autoimmune hemolytic anemia
penicillin and methyldopa induced immune hemolysis
transfusion reaction

intravascular hemolysis

paroxysmal nocturnal hemoglobinuria
G6PDase deficiency
some IgM autoimmune hemolytic anemia
quinidine-induced immune hemolytic anemia
malaria
mechanical (prosthetic valves, stenosis, etc.
microangiopathic (DIC, TTP, HUS, SLE, malignant hypertension)

RBC basophilic stippling

chronic disease
lead posioning
iron deficiency
thalassemias

bite cell

G6PDase deficiency

PMNs with > 5 segments

B12 or folate deficiency

schistocyte/helmet cell

DIC
TTP
HUS
mechanical hemolysis

tear drop RBC

myelofibrosis

heinz bodies

alpha thalassemia
G6PDase deficiency

howell-jolly bodies

hyposplenia or asplenia

case control study

compares diseased to non-diseased, looking for prior exposure or risk factor (retrospective)

cohort study

compares exposed to non-exposed, looking at likelihood of disease (prospective or retrospective)

case series

tracks small group of patients with a known exposure and examines their outcome (prospective or retrospective)

interstitial lung inflammation with loose non-caseating granulomas

hypersensitivity pneumonitis (hypersensitivity reaction often seen in farmers, people exposed to birds)

cause of menopause sx

fewer oocytes --> decreased estrogen

autoregulation of blood flow to heart

NO, adenosine, decreased O2

autoregulation of blood flow to skeletal muscle

K+, lactate, adenosine

autoregulation of blood flow to brain

CO2 (pH)

increased fremitus

consolidation (pneumonia)

glomerular injury d/t neutrophils

nephritic syndrome

glomerular injury d/t cytokines

nephrotic syndrome

increased BUN/Cr ratio

� pre-renal renal failure (aka pre-renal azotemia)
� renal failure due to decreased renal blood flow
� urea is retained (with H20 and Na) in attempt to conserve volume.

decreased BUN/Cr ratio

� intrinsic renal
� renal failure due to acute tubular necrosis > glomerulonephritis
� urea is excreted d/t impaired reabsorption

superior vena cava syndrome

feeling of fullness in head and neck, usually secondary to compression by upper lobe lung/mediastinal mass

reversible cell damage

dec ATP synth
impaired Na/K pump --> cell swelling
chromatin clumping
ribosomal detachment --> dec protein synth
dec glycogen
fatty change

irreversible cell damage

nuclear pyknosis, karryorhexis
Ca influx --> caspase activation
plasma membrane damage
lysosome rupture
increased mitochondrial permeability --> cytochrome C release --> caspase activation

fatty infiltration of bone marrow

aplastic anemia

huntington's lesion

striatum

hemiballismus lesion

subthalamic nucleus

infante with somnolence, vomiting, cerebral edema, decreased BUN, hyperammonemia

ornithine transcarbamoylase deficiency

infantile cataracts, doesn't track objects, absent social smile

galactokinase deficiency

infantile cataracts, hepatomegaly, jaundice, failure to thrive

uridyltransferase deficiency

causes of Down syndrome

1) meiotic nondisjunction (95%)
2) unbalanced robertsonian translocation (extra arm on Ch 21)
3) mosaic trisomy 21

treatment of hyperammonemia (HCV, urea cycle deficiency)

limit protein in diet
benzoate, phenylbutarate (bind a.a.'s, increased aa exretion)
lactulose (acidify GI tract, trap NH4 for excretion)

effect of hyperammonemia on metabolism

decreased alpha ketoglutarate, inhibiting TCA cycle

Tay-Sach's (enzyme, accumulated substance)

hexosaminidase, GM2 ganglioside

metachromatic leukodystrophy (enzyme, accumulated substance)

arylsulfatase, cerebroside sulfate

fabry's (enzyme, accumulated substance)

alpha-galactosidase, ceramide trihexoside

krabbe's (enzyme, accumulated substance)

beta-galactocerebrosidase, galactocerebroside

gauche's (enzyme, accumulated substance)

glucocerebrosidase, glucocerebroside

niemann-pick

sphingomyelinase, sphingomyelin