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USMLE facts 4

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ang93's version from 2017-04-30 10:51

NMBE

Histology

Microbiology

Question Answer
cold agglutinin infxnsmycoplasma pneumoniae, EBV, and hemotologic malignancy
cell R CMVcell intergrins
cell R EBVCR2 (CD21)
cell R rabiesnicotinic AchR
cell R rhinovirusICAM1 (CD54)
how do you dx tetanusHX and PHYSICAL! ITS CLINICAL!
memorize

Cardio

Question Answer
inc JVD with inspirationkussmauls sign - RSHF
nesiritidesynthetic B type natriuretic peptide
reduce mortality in HFBB, ACEI, ARBS, NItrates, Spironelactone, Hydralazine (BANISH HF)
systolic HF<55% EF, large ventricular chamber (thin walls), S3 (filling dilated vent)
diastolic HFnl or inc EF, thick walls, small chamber, S4 gallop (atria contract into stiffened ventricle)
ST depression T inversionsangina pectoris, unstable angina, NSTEMI
prevent coronary stent thrombosisaspirin and clopidogrel
purpose of PTCA1 or 2 vessle dz not involving left main coronary
CABG purposeL main coronary artery dz, symptomatic 3 vessel dz, LVEF <40% >70% stenosis in ALL 3 vessels
management anginaNG, BB, Aspirin, CCBs
acute coronary syndromeacute plaque rupture and coronary artery thrombosis
partial artery occlusion leading to necrosisNSTEMI - ST depression
memorize

Pulm

Question Answer
theophyllineadenosine R antagonist and PDEi, indirect adrenergic agent w narrow TI
sudden onset tachypnea, chest painPE
fat embolism syndromeresp distress, neuro. petechial rash
diffusion impairmentend stage interstitial dz
reid indexratio thickness of mucous gland layer to bronchial wall thickness btwn epith and cartilage , measures gland enlargment
nl reid index4
reid index correlates wduration and severity of bronchitis
path of obstructive sleep apneaneuromuscular weakness of oropharynx
electric stimulation of what nerve will help sleep apneahypoglossal - inc diameter of the oropharynx and dec freq of events
clinical manifestations of asbestos exposurepleural plaque (parietal pleura) - dense collagen becomes calcifies, asbestosis - diffuse pulm fibrosis, asbestos bodies ( golden brown beaded rods w translucent centers), bronchogenic carcinoma - MC malig assocd w asbestos exposure, malignant mesothelioma
smoking and asbestossynergism
sepsis complication in lungsARDS neutropils provoke inflam response leads to capaillary damage and leakage of protein and fluid into alveolar space
thickened bronchial walls, lymphocytic infiltration, mucous gland enlargement, pathcy sq metaplsiachronic broncitis
leading cause of chronic bronchitissmoking
memorize

GI

Question Answer
chronic autoimmune liver dz, lymphocytic infiltrates and destruction of small and mid sized intrahepatic bile ductsprimary biliary cholangitis
panlobular microvesicular steatosis liver in young childreye syndrome
failed apoptosis of epith cells during fetal life - GIduodenal atresia
failure to recanalize 8-10 wks gestationduodenal atresia
vascular injury and intestinal atresiajejunum/ileum
bilious and nonbilious emesis, double bubble signduodenal atresia
down syndrome assoc gi dzduodenal atresia
bilious emesis and abdominal distensionjejunum/ileum
constipation abdominal distension atresiacolonic
apple peel deformitySMA obstructed - blind ending proximal jejunum - then terminal ileum spiraled around ileocolic vessel
memorize

Renal

Neuro

Question Answer
serotonin releasing neuronsraphi nuclei - widely disseminated in CNS
role of serotonin sleep wake, anxiety, mood, psychosis, sexuality, eating behavior, impulsitivty
rapidly progressive dementia, myoclonic jerks, multiple vacoules in gray matterCJD
path CJDabnl prion protein - nL present in host neurons but change in secondary struct becomes resistant to enzymatic digestion by proteases and leads to accumulation
tx CJDnone, fatal
progressive dementia, general paralysissyphillis
immunocomp pt, patches of demyelination due to preferential infxn of oligodendprogress multifocal leukoencephalopathy (JC Virus)
abnl measles, progressive dementia, spasticity, seizuressubacute sclerosing panencephalitis
optic radiationproject to primary visual cortex
meyers looptemporal
saddle anesthesia, loss of anocutaneous reflexcauda equina syndrome - S2-S4 damage
spinal cord terminatesL2
lesions at L2conus medullaris syndrome
conus medullari syndromeflaccid paralysis bladder and rectum, impotence, saddle (S3-S5) anesthesia
conus medullaris vs cauda equina injuryc.m. - herniation, tumors, spinal fx, c.e. - massive rupture intervert disk
cauda equina syndrome sxLOW BACK PAIN RADIATING TO ONE OR BOTH LEGS, saddle anesthesia, loss of anocutaneous reflex, bowel and bladder dysfxn, loss ankle jerk reflex w plantar weakness
epidural hematomacomplication epidural anesthesia, presents wi hours to days, suddent onset back pain or radicular pain w prog to complete or patial paralysis of LEs
trigem neuralgia distibutionV2, V3
alpha 1 Rsperipheral vasc(inc SBP), bladder(internal urethral sphincter), eye (mydriasis)
alpha 1 agonistsE, NE, phenylephrine, methoxamine
B1 Rheart (inc HR, contractility, conductance)
B1 agonistsE, DA, dobutamine, isoproterenol
B2 Rperipheral vasc (skel muscle - vasodilation, dec DBP), bronchi (diln), uterus (relaxn - tocolysis)
B2 agonistisoproterenol, terbutaline, ritodrine
lucid intervalEPIDURAL HEMATOMA
dont give with benzos in the elderly bc cause severe sedationfirst generation H1 receptor antagonists (diphenhydramine and chlorpheniramine)
CGG repeatsfragile x
cause of clincal condition of fragile xhypermethylation and inactivation of FMR1
cord hemisection above T1brown sequard syndrome - ipsilate spastic paralysis, ipsilat touch sensory loss, contral lat P/T loss AND horners syndrome
ALSmixed UMN & LMN
MC COD ALSresp failure
corneal blink reflexV1 senses -> CN7 (orbicularis oculi muscle)
liquid anterior compartmentaqueous humor
liquid post compartmentvitreous humor
layers of the eyesclera, choroid, retina
recurrent lobar hemorrhage (occipital and parietal)cerebral amyloid angiopathy
MC cause of intracranial hemorrhage in childrenAVM
embolic strokemultiple infarcts involving the cerebral cortex and higher likelihood spont hemorrhagic transformation
hypertensive encephalopathyprogressive headache and n/v followed by nonlocalized neuro sx (confusion)
hypoxic encephalopathyglobal interruptn bs (cardiac arrest), dec consciousness
charcot bouchardchronic hypertension and typically DEEP BRAIN (bg, cerebellar nuclei, thalamus, pon)
progressively worsening, symmetrical, flaccid muscle weakness w absent or dec reflexes, starts in LEs and ascends upward GBS
long circumfrenciallateral brainstem syndomes
paramedianmedial brainstem syndromes
subacute sclerosing panencephalitisabsent matrixprotein, accumn of viral nucleocapsics wi neurons and oligodend -> intranuclear inclusions -> inflam, demyelin, gliosis
neurodegen of midbrain and frontal subcortical white matterprogressive supranuclear palsy - parkinsons
rapidly progressive gait dysfxn and falls, executive fxn loss, vertical gaze palsyprogressice supranuclear palsy - parkinsons
neonatal INTRAvent hemorrhagefragile germinal matrix inc in freq w dec age and birth weight, complication of prematurity
elevated AchE in amniotic fluidneural tube defect
first area of damage in global cerebral ischemiahippocampus
most susceptible to ischemia in brainpyramidal cells of hippocampus and neocortex, purkinje cells of cerebellum
progressively worsening dizziness, limb and truncal ataxis, dysarthria, and visual disturbances, small cell lung cancerparaneoplastic cerebellar degen (autoimmune)
Abs in pararneoplastic cerebellar degenanti-yo, anti-p/q, anti-hu
normal pressure hydrocephalusdec CSF resorption, ventricle progressively expand to accommodate - WACKY WET WOBBLY (cognitive disturbance, urinary incontinence, gait difficulties)
ventriculomegaly out of proportion to or wo corresponding sulci enlargmentNPH
how do you dx NPHimprovement w CSF removal
vent enlargement in proportion to sulci enlargemnts, gen brain atrophyhydrocephalus ex vacuo
marker of poor prognosis after cardiac arrestnonreactive pupils - indicates anoxic damage to brainstem
POMC productsbeta endorphin, ACTH, MSH (think stress axis - opioid sys)
memorize

Neuro - CNs

Question Answer
anterior cranial fossaCN1
middle cranial fossaCN2-6
posterior cranial fossCN7-12
CN1cribiform plate
optic canalCN2. opthalmic art, central retinal vein
SOFCN3, 4, V1, 6, opthalamic vein, symp fibers
foramen rotundumV2
foramen ovaleV3
foramen spinosummiddle meningeal a + v
internal acoustic meatusCN7.8
jugular foramenCN 9,10,11, jugular vein
hypoglossal canalCN12
foramen magnumspinal roots CN11, brain stem, vert arteries
dysphonia and hoarsnessCN10 injury
CN9 somatic motorstylopharyngeus (elevates larynx while swallowing)
CN9 general sensoryTM (inner surface), eustacian tube, posterior 1/3 tounge, tonsilar region. upper pharynx (afferent gag reflex), carotid body, carotid sinus
memorize

Psych

Question Answer
somatic sx disorderexcessive anxiety & preoccupation w >=1 unexplained sx
neurologic sx incompatible w any neuro dz, often acute onset assocd w stressconversion disorder
memorize

MSK

Question Answer
femoral nerveflexion muscles at hip (illiacus and sartorius) and extension at knee (quadriceps femoris), sensory ant thigh and medial leg
inf glutealgluteus max (extension and ext rotation at hip) difficult to rise from seat and climb stair
obturator nervethigh adduction, medial thigh sensory
sciatic nerveposterior compartment thigh (hamstrings)
memorize

Derm

Biochemistry

Question Answer
Vit E defhemolysis and neuro dysfxn (free radical damage of cell membranes) - ataxia, loss of p/v, loss of deep tendon reflexes - appears similar to f. ataxia and B12 def
memorize

Immunology

Question Answer
IL1Causes fever, acute inflammation. Activates endothelium to express adhesion molecules. Induces chemokine secretion to recruit WBCs.
IL2Stimulates growth of helper, cytotoxic, and regulatory T cells, and NK cells.
IL3Supports growth and differentiation of bone marrow stem cells. Functions like GM-CSF.
IL4Induces differentiation of T cells into Th2 cells. Promotes growth of B cells. Enhances class switching to IgE and IgG.
IL5Promotes growth and differentiation of B cells. Enhances class switching to IgA. Stimulates growth and differentiation of eosinophils.
IL6Fever and acute phase reactants
IL8major chemotactic factor for neutrophils
IL10Attenuates inflammatory response. Decreases expression of MHC class II and Th1 cytokines. Inhibits activated macrophages and dendritic cells. Also secreted by regulatory T cells
IL12Induces differentiation of T cells into Th1 cells. Activates NK cells.
TNFaActivates endothelium. Causes WBC recruitment, vascular leak.
IFNgSecreted by NK cells and T cells in response to antigen or IL-12 from macrophages; stimulates macrophages to kill phagocytosed pathogens. Inhibits differentiation of Th2 cells.Also activates NK cells to kill virus-infected cells. Increases MHC expression and antigen presentation by all cells
causes cachexia in malignancyTNFa
mediates sepsisIL1, 6, TNFa
C5aanaphylaxis and neutrophil chemotaxis
C3a4a5aanaphylaxis
classic pathwayIgG, IgM
alternativemicrobe surface molecules
lectinmannose or other sugars on microbe surface
C3bopsonization and clearance of immune complexes
C3 definc risk severe recurrent pyog sinus and RTI, inc suscept to T3HSR
C5-9 defrecurrent neisseria infxn
C1 esterase inhib defhereditary angioedema (unreg activn of kallikrein -> inc bradykinin), DEC C4 levels, dont use ACEIs in these pts
CD55 defDAF def, complement med'd lysis of RBCs, and paroxysmal nocturnal hemoglobiuria
macrophage cytokinesIL1, IL6, IL8, IL12, TNFa
T cell cytokinesIL2, IL3
TH1 cytokinesIFNg
TH2 cytokinesIL4, IL5, IL10
memorize

Stats

Pharm – General

Question Answer
buprenorphinepartial opiod agonist, LOW efficacy, HIGH potency - prevent binding of other opioids - cause W/D
MOA opioidsbind G protein coupled receptors mimic endogen opioids
long term use of opioidsinc pain sensitivity - inc R turnover, decoupling Rs, upreg NMDA Rs
classes of DA agonistergot (bromocriptine) and nonergot (pramipexole, ropinirole)
delay need for levodopaDA agonists
enhances endogenous DA, allev motor sxamantidine
inc amt of levodopa avail for brainCOMTi (entacapone, tolcapone), dopa decarboxylase inhib (carbidopa)
tx tremor predom sx parkinsonsanticholinergics - trihexyphenidyl and benztropine (inhib central M receptors)
binds to same portion GABA-A like benz, used for shorterm tx insomniazolipdem
imprt characteristics zolipdemless potenanial for addiction and tolerance, less incidence W/D sx, no anticonvilsant props, no muscle relaxing
MS txdz modifying (B-IFN, natalizumab), acute flares - IV steroids
tx ALSnoncurable, Riluzole can prolong survival 2-3 mo - blocks glutamatergic transmission
antiepileptic that inhibs presynaptic VG-Cagabapentin
antiepileptic that inhibs vesicle fusionlevetiracetam
nerve that supplies middle ear and muscle masticationV3
baclofenGABA-B agonist - tx muscle spasms
memorize

Pharm – Adverse Effects

Question Answer
theophylline SEseizures and cardiac arrhythmia
narrow spectrum anticonvulsantscarbamazepine, gabapentin, phenobarb, phenytoin
broad spectrum anticonvulsantslamotrigine, levetriacetam, topiramate, valproic acid
intial status epilepitusbenzos
after benzos, status epilepticusphenytoin
TOC tonic clonic seizurespheytoin, valproic acid
TOC focal seizurecarbamazepine
TCA have strong ___ propertiesanticholinergic!, confusion, constipation, and urinary retention
memorize

WITHDRAWAL

Question Answer
opioid w/d sxn/v, myalgias, dilated pupils, diaphoresis, tachycardia
alcohol wd 3-36hmild sx - diaphoresis, GI upset, headache, nv, palpatations, tremulous
alcohol wd 6-48hseizures
alcohol wd 12-48hvisual and aud hallucinations
alcohol wd 48-96hdelirium tremens
delerium tremensdelirium, agitations, autonomic instability
memorize

Toxicology

Question Answer
mydriasis, tachycardia and HTNcocaine intox
miosis, bradycardia, and hypotensionopioid intox
bitter almon breathcyanide
cyanide MOAinhib cytochrome oxidase in ETC
what tox inhibt ETCCN, CO
directly inhib ATPsynthaseoligomycin
memorize

Heme/Onc