4/17/19 Flashcards
Given a positive test result, what is the probability that a patient has the disease?
Calculate PPV = a / (a + b)
number of people with disease who test positive among all those who test positive
PPV varies with disease
prevalence
if disease prevalence increases, PPV increases
Hereditary angioedema is a rare AD disorder associated with
painless episodes of swelling involving face, lips, larynx, extremities
Hereditary angioedema is caused by
AD
C1 inhibitor deficiency
Sickle cell disease causes what kinds of hemolysis
intra and extravascular hemolysis
Sickle cell disease causes increase in
indirect bilirubin
lactate dehydrogenase
decreased haptoglobin
What is haptoglobin
Acute phase reactant
- decreased in sickle cell disease
- binds circulating hemoglobin
- reduces renal excretion of free Hgb preventing tubular injury
African american with swelling hands and feet
sickle cell disease
dactylitis (hand-foot syndrome) - vasoocclusive symptoms
Transplant patients (esp. lung) at risk for what virus
CMV
enveloped dsDNA
Herpesviridae family
Patients at risk for CMV infection
transplant
HIV
fetuses (congenital infection)
In HIV, CMV usually causes
esophagitis
colitis
retinitis
CMV histology
- enlarged cells with intranuclear and intracytoplasmic inclusions (viral particles)
- often surrounding halo (owl’s eye)
Ppx for CMV in transplant patients
valganciclovir
Influenza virus is an
enveloped
ssRNA
P450 inducers
phenytoin barbituates rifampin carbamazepine griseofulvin chronic alcohol consumption
P450 inhibitors
isoniazid cimetidine macrocodes azole antifungals grapefruit juice
Tight tie causing lightheadedness
carotid sinus hypersensitivity (baroreceptors)
dilation of internal carotid artery
severe bradycardia, hypotension, syncope
baroreceptors are found in the
carotid sinus
baroreceptors work by
arterial wall stretch as an indication of systemic BP
How does the carotid sinus work
afferent limb: baroreceptors in carotid sinus –> medullary center via Hering nerve (glossopharyngeal nerve CN IX)
efferent limb: from medulla carries PNS impulses via vagus nerve
Carotid massage or pressure can cause
- stimulation of baroreceptors
- increase in PNS output/withdrawal of SNS output to heart and peripheral vasculature
- decreased BP (peripheral vasodilation)
- decreased CO (decreased contractility/SV/HR)
The vagus nerve controls BP by
afferent limb: for nerve fibers of aortic arch baroreceptors
efferent limb: for carotid sinus reflex
What is a low osmolarity in the tubular system
100-300
Where is the lowest osmolarity in the tubule system
distal convoluted tubule
100 mOsm/L
Where is the highest osmolarity in the tubule system
descending limb of loo of Henle (when ADH is high)
collecting duct
1200 mOsm/L
Decerebrate posturing (extending) is from damage to
brainstem at/below level of the red nucleus (midbrain tegmentum, pons)
Decorticate (flexor) posturing is from damage to
neural structures above the red nucleus (cerebral hemispheres, internal capsule)
Which one is worse, decerebrate or decorticate posturing
decerebrate
which Ig can cross the placenta
IgG
Hemolytic disease of the newborn is caused by
severe autoimmune hemolytic anemia
destruction of fetal RBCs by maternal Ans directed against fetal erythrocyte Ag
Abs cross the placenta and opsonize fetal erythrocytes causing hemolysis
Erythroblastosis fettles is MCC by
Rh incompatibility, D antigen
Hemolytic disease of the newborn can cause what in the baby
- profound anemia - stimulates release of immature nucleated erythrocytes = persistent extra medullary hematopoiesis
- jaundice (poss kernicterus)
- generalized edema (hydros fetalis d/t accumulation of interstitial fluid)
Panic disorder is described as
recurrent, unexpected panic attacks, concern about future panic attacks
Acute stress disorder is described as
exposure to a traumatic event followed by development of characteristic symptoms )re-experiencing, avoidance, arousal) lasting from 3 days to 1 month
Adjustment disorder requires
symptoms that develop in response to an identifiable stressor
Generalized anxiety disorder is described as
chronic multiple worries, excessive worry for at least 6 months, may or may not precipitate panic attacks
Recent MI
sharp/pleuritic chest pain
exacerbation with swallowing
- peri-infarction pericarditis
- 2-4 days post transmural MI
- reaction to necrosis of myocardium near epicardial surface
- resolves in 1-3 days with aspirin
Peri-infarction pericarditis involves damage to
visceral and parietal pericardium localized to areas overlying necrotic myocardial segment
Dressler syndrome
- autoimmune mediated pericarditis
- provoked by antigens exposed or created by infarction and necrosis of cardiac muscle
- onset weeks to months after MI
- pericardium diffusely affected
Nutrients affected by gastric bypass
Iron B12 Folate fat soluble vitamins, esp D calcium
Methacholine MOA
inhaled muscarinic cholinergic agonist
induces bronchoconstriction
Patients with asthma react to methocholine by
- hyper-responsitivity
- reduction in FEV1 at lower doses than in those without asthma
Muscle biopsy showing ragged red fibers
mitochondrial myopathy
maternal inheritance
myopathy
nervous system dysfunction
lactic acidosis
ragged red fibers on biopsy
mitochondrial myopathies
PSGN presents with
elevated ASO
low C3 levels
Lumbar puncture is done between levels
3rd and 4th lumbar vertebrae
Hyponatremia
lung mass
headache, weakness, altered mental status, seizures
SIADH
Small cell lung carcinomas are tumors of what origin
neuroendocrine
SIADH leads to
euvolemic hyponatremia
decreased plasma osmolality
elevated urine osmolality
SIADH gets euvolemic hyponatremia bc
- excessive water absorption = subclinical hypervolemia
- increase in ECF suppresses RAAS
- stimulates production of natriuretic peptides leading to excretion of sodium in urine
= normal ECF volume and low plasma osmolality
SIADH do not have
signs of volume overload
- peripheral edema
- pulmonary crackles
- elevated JVP
long term PPIs are associated with
osteoporotic fractures
possibly by decreasing calcium absorption
Bilateral wedge-shaped strips of necrosis over cerebral convexity, parallel and few centimeters later to inter hemispheric cerebral fissure
- global cerebral ischemia
- neuron cell death is at areas most vulnerable to hypoxia = watershed zones
Irreversible cell injury is associated with
mitochondria vacuolization
Disaggregation of granular and fibrillar elements of the nucleus is associated with
clumping of nuclear chromatin
reversible cell injury
inflammation phase of wound healing
- fibrin clot for hemostasis
- cytokines from activated plt and damaged cells lead to migration of neutrophils (24 hr) and macrophages (2-3 days later)
proliferation phase of wound healing
- 3-5 days after injury
- fibroblasts and endothelial vascular cells form connective tissue and blood vessels
- epithelial cells begin to proliferate at dermal edges and secrete BM material
maturation phase of wound healing
- fibrosis/scar formation during 2nd week after injury
- active fibroblasts synthesize collagen, elastin, connective matrix
Hypertrophic/keloid formation is d/t
increased TGF-beta activity
Fibrosis of the lung, liver, kidney with chronic inflammation is d/t
increased TGF-beta activity
What is capitation
- payment structure underlying HMO’s
- payor pays fixed, predetermined fee to cover all medical services required by a patient
What is global payment
arrangement where insurer pays provider single payment to cover all expenses associated with an incident of care
Dyspnea/cough
nodular pleural thickening
pleural effusion (hemorrhagic)
mesothelioma
Histology of mesothelioma
numerous long, slender microvilli, and abundant tonofilaments
immunohistochemical markers for mesothelioma
pancytokeratin
HCM is caused by
genetic mutations in structural proteins of cardiac sarcomere
- beta-myosin heavy chain
- myosin-binding protein C)
histology of HCM
cardiomyocyte hypertrophy
haphazard cellular arrangement and interstitial fibrosis
Before surgery, who has to confirm the surgical site
the nurse and surgeon verify independently
Hepatic steatosis characterized by
TG accumulation within hepatocellular cytoplasm
alcohol-induced hepatic steatosis is d/t
decrease in FA oxidation secondary to excess NADH production from
- alcohol dehydrogenase
- aldehyde dehydrogenase
Fulminant hepatitis in pregnant women
hepatitis E
Hepatitis E is an
undeveloped
ssRNA virus
Opioids cause what in the sphincter of oddi
contraction and spasm
Tumor lysis syndrome is characterized by
hyperphosphatemia
hyperkalemia
hyperuricemia
hypocalcemia
Dobutamine causes
Increased: cAMP isotropy chronotropy cardiac output myocardial oxygen consumption (trigger/exacerbate myocardial ischemia)
Decreased:
LV filling pressures
SVR
Dobutamine is used in
cardiogenic shock
refractory HF w/severe LV systolic dysfunction
Do not use dobutamine in
decompensated HF
Dobutamine MOA
beta-1 agonist
weak beta-2 agonist
minimal activity of alpha-1 agonist
Gs receptor
Hibernating myocardium
state of chronic myocardial ischemia
- decreased metabolism and function to match concomitant reduction in coronary blood flow
- new equilibrium prevents myocardial necrosis
- decreased contractility and LV systolic dysfunction
- coronary revascularization restores blood flow and improves contractility and LV function
Concentric LV hypertrophy is associated with
- decreased LV compliance
- increased angiotensin II signaling
- increased cardiac myosin heavy chain-beta expression
There is higher Cl in RBC venous blood bc
chloride shift
- carbonic anhydrase forms HCO3 from CO2 and water
- excess HCO3 transferred out of RBC into plasma via exchange with Cl
In COPD, changes are
increase in RV and TLC
decrease in FVC
more profound decrease in FEV1
decrease in FEV1/FVC
Damage to what nerve with repetitive use of a screwdriver, direct trauma, subluxation of radius
Radial nerve during passage through the supinator canal
weakness during finger/thumb extension
no wrist drop or sensory deficits
nontreponemal serologic tests
RPR
VDRL
mix patients serum with cardiolipin-cholesterol-lecithin antigen
lower sensitivity in early infection
treponema diagnostic serology
FTA-ABS
TP-EIA
Ab to treponema antigens
greater sensitivity in early disease
RF is an Ab that targets
Fc portion of IgG
seen in RA and AI
Hepatic abscess in US caused by
- S. aureus via hematogenous seeding to liver
- enteric bacteria (E. coli, Klebsiella, enterococci) by ascending biliary tract, portal vein pyemia, direct invasion from adjacent area
Hepatic abscess in third world countries
-entamoeba histolytica via food borne exposure and poor sanitation
Bacillus anthraces main virulence factors
- encased in antiphagocytic polypeptide capsule composed of D-glutamic acid
- edema factor, mimics adenylate cyclase
intracellular polyphosphate granules are associated with what bacteria
diphtheria
loeffler medium and methylene blue staining
Prevent migraines with
- anticonvulsants (topiramate, valproate)
- TCA (amitriptyline)
- beta blockers (metoprolol, propranolol)
abort migraines with
- triptans
- NSAIDs, acetominophen
- antiemetics
- ergotamine
- middle age, insidious onset
- symmetrical proximal muscle wasting w/mild pain
- difficulty climbing stairs, getting up from chair, carrying heavy objects
polymyositis
Polymyositis and dermatomyositis can occur paraneoplasically especially with
adenocarcinoma
biopsy of polymyositis shows
endomysial mononuclear infiltrate
patchy fiber necrosis
labs for polymyositis
- elevated muscle enzymes (CK, aldolase)
- ANA, anti-Jo-1
Associated complications of polymyositis
interstitial lung disease
myocarditis
Anti-Jo-1 is a
anti-histidyl-tRNA synthetase
specific for polymyositis and dermatmyositis
dermatomyositis biopysy shows
perifascicular inflammation in segmental pattern without vasculopathy
muscle biopsies in MG and LEM are
normal
Dilated cardiomyopathy leads to
increased right atrial pressure
increased LVED pressure
Charcot-bouchard aneurysm affects
deeper brain structures/intracerebral hemorrhage
- BG
- cerebellum
- thalmus
- pons
HTN
Saccular (berry) aneurysm affects
circle of willis
subarachnoid hemorrhage
see in ADPKD, Ehlers-Danlos, HTN
Neuroleptic malignant syndrome is caused by
dopamine antagonist
1-3 days for onset
hyporeflexia
Treatment for neuroleptic malignant syndrome
benzos
dantrolene
dantrolene MOA
postsynaptic muscle relaxant
Serotonin syndrome is caused by
serotonergic agent
onset less that 1 day
hyperreflexia
Hormone sensitive lipase does what
in adipose tissue
mobilizes store TG into FFA and glycerol
used during starvation to provide substrates for hepatic gluconeogenesis and ketone formation
Hormone sensitive lipase is activated by
stress hormones
catecholamines
glucagon
ACTH
Hormone sensitive lipase is inhibited by
insulin
Hormone sensitive lipase MOA
stress hormone to Gs protein on adipocytes
increased cAMP
activation of protein kinase A
HSL activated and lipolysis
Hyperprolactinemia from prolactinoma suppresses
GnRH production = oligomenorrhea/amenorrhea
cohort studies test compare
disease incidence
case control studies compare
risk factor frequency between disease and no disease
cross sectional studies compare
disease prevalence
compare disease incidence
cohort
compare risk factor frequency between disease and no disease
case control
compare disease prevalence
cross sectional
complications after SAH
arterial vasospasm
rebleeding
hydrocephalus
seizures
MC complication after SAH
- arterial vasospasm
- unopposed vasoconstriction causes delayed cerebral ischemia
- change in mental status and/or new focal near deficits
- 3-12 days after SAH
- no changes seen on new CT
Lab to do before prescribing metformin
creatinine level
Hemosiderin-laden macrophages (heart failure cells) are signs of
chronic lung congestion
macrophages digest RBC that leak from capillaries
Sign of acute pulmonary edema
- intraaveolar transudate appears as acellular pink material
- engorged alveolar capillaries
Signs of early interstitial lung disease (idiopathic pulmonary fibrosis)
mononuclear interstitial pulmonary infiltrates
Signs of pulmonary hemorrhage syndromes like Goodpasture and other vasculitides
focal necrosis of alveolar wall w/intraalveolar hemorrhage
cutaneous neurofibromas from NF-1 are comprised of
Schwann cells
NF-1 are at increased risk of developing
optic gliomas
pilocytic astrocytomas
causing elevated intracranial pressure and HA
Cryptococcus is characterized by
round/oval yeast surrounded by thick polysaccharide capsule
nephrotic syndrome with pitting edema is d/t
hypoalbuminemia
decreased oncotic pressure
Abnormal vaginal bleeding with significantly increased HCG after normal/abnormal pregnancy
gestational choriocarcinoma (malignant)
gestational choriocarcinoma arises from
trophoblast
gestational choriocarcinoma invades the
uterine wall via hematogenous spread
MC distal site of metastasis for gestational choriocarcinoma
lungs (SOB and hemoptysis)
histologically, gestational choriocarcinoma looks like
- abnormal proliferation of mononuclear cytotrophyblasts
- multinuclear syncytiotrophoblasts
- no villi present
What are the two malignant gestational trophoblastic diseases
gestational choriocarcinoma
invasive mole
Difference in findings of partial and complete mole
partial - focally hyperplastic trophoblasts, focally enlarged hydropic villi, present embryonic tissue, triploid
complete - diffusely hyperplastic trophoblasts, diffusely enlarged hydropic villi, absent fetal/embryonic tissue
Difference in findings of invasive mole and gestational choriocarcinoma
invasive mole - diffusely hyperplastic trophoblasts with myometrial invasion, diffusely enlarged hydropic villi, absent fetal/embyronic tissue
gestational choriocarcinoma - diffusely anapestic/necrotic trophoblasts with vascular invasion, absent villi, present of absent fetal/embryonic tissue
Which malignant gestational trophoblastic disease has myometrial invasion
invasive mole
Which malignant gestational trophoblastic disease has vascular invasion
gestational choriocarcinoma
which mole has present fetal/embryonic tissue
partial mole
triploid
efferent renal arteriole constriction causes
increase GFR
increase FF
which chronic efferent renal arteriole constriction what will happen to GFR
decrease
RPF low secondary to severe efferent arteriolar constriction
substantially increased capillary oncotic pressure results in overall decrease in GFR
what always increases with renal efferent arteriole constriction
FF
patients with vesicoureteral reflux are at increased risk for
chronic pyelonephritis
renal scarring at upper and lower poles of kidney
If vesicoureteral reflux is not corrected it can lead to
loss of nephrons
secondary hypertension
KIT receptor tyrosine kinase mutation
systemic mastocytosis
- expression of mast cell typtase
- excessive histamine
- induces gastric acid secretion = ulcers
- inactivates pancreatic and intestinal enzymes = diarrhea
What comes out the superior orbital fissure
CN III, IV, V1, VI, ophthalmic vein, SNS fibers
What comes out of the foramen spinosum
middle meningeal artery and vein
What comes out of the optic canal
CN II, ophthalmic artery and central retinal vein
What comes out of the internal acoustic meatus
CN VII and VIII
what comes out of the jugular foramen
CN IX, X, XI, jugular vein
what comes out hypoglossal canal
CN XII
what comes out of the foramen magnum
spinal roots of CN XI, brain stem, vertebral arteries
posterior cranial fossa has which foramen
internal acoustic meatus
jugular foramen
hypoglossal canal
foramen magnum
noncompetitive or irreversible inhibitors have
decreased maximal effect, Vmax
no significant change on Km (affinity)
phenoxybenzamine is a
irreversible alpha 1 and 2 rec antagonist
reversible competitive inhibitor have
increased affinity, Km
almost all volatile anesthetics increase
cerebral blood flow
increased ICP
inhalation anesthetics can cause which AE
myocardial depression
hypotension
respiratory depression
decreased renal function
mitochondrial diseases are characterized by
exclusively maternal inheritance
heteroplasty - different presentations due to different distribution of affected mitochondria
variable expressivity refers to
differences in severity of AD disorders
does not apply to mitochondrial diseases
genetic imprinting is
selective inactivation of paternal or maternal alleles
transforming unacceptable feelings/impulses into the opposite
reaction formation
expressing unacceptable feelings through actions
acting out
reverting to earlier developmental stage
regression
channeling impulses into a socially acceptable behavior
sublimation
putting unwanted feelings aside to cope with reality
suppression
Dihydrofolate reductase and DNA polymerase are used in
DNA synthesis
S phase of cell cycle
What is a regulator of transition from G1 to S phase
Rb protein
Serotonin is derived from
tryptophan
Tyrosine is a precursor for
thyroxine DA Epi NE melanin
Methionine is a precursor for
cytosine, carnitine, taurine, lecithin
Treatment for serotonin syndrome
airway and temperature maintenance
hydration
cryoheptadine
What is cryoheptadine
serotonin antagonist
1st gen antihistamine w/nonspecific 5-HT1 and 5-HT2 rec antagonism
Flumazenil is the antidote for
benzodiazepine OD
What should be avoided in serotonin syndrome
long half life antihypertensives like propranolol
risk of hypotension and shock
how to treat HTN in serotonin syndrome
short acting meds
esmolol
nitroprusside
corticosteroid use causes increase of what WBC
neutrophils
GFR increases with
higher glomerular hydrostatic pressure
GFR decreases with
increasing Bowman’s capsule hydrostatic pressure
higher glomerular capillary oncotic pressure
Ureteral obstruction causes
increase in hydrostatic pressure proximal to constriction –> Bowman’s space
decreased GFR
Which bacteria are assoc with struvite stones
urease producing
klebsiella
proteus
increased pH
Major adaptive immune mechanism that prevent reinfection with influenza
anti-hemagglutinin abs
Guillain-Barre Syndrome histology
- inflammatory infiltrate within the endoneurium
- lymphocytes and macrophages extend from small vessels to associated nerve axon
- lipid laden macrophages
The alpha helical regions of G protein are for
anchoring to cell membrane
Those with giant cell arteritis, about half will also have
polymyalgia reumatica
Giant cell arteritis biopsy
focal granulomatous inflammation of the media with intimal thickening, elastic lamina fragmentation, giant cell formation (without granulomas)
Giant cell arteritis is histologically identical to
Takayasu arteritis that’s usually in aortic arch and affects younger patients
Truncating mutations in TTN gene affecting sarcomere protein titin with sudden death
DCM
Acute hemolytic transfusion reaction
Type II hypersensitivity
C3a and C5a cause vasodilation/shock
C5b-9 causes complement mediated cell lysis
Muscle that goes through greater sciatic foramen
Piriformis
Muscle that goes through lesser sciatic foramen
obturator internus
