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Flashcards in test #22 4.12 Deck (133)
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signs of hypothyroidism

fatigue, weight gain, constipation, SLOWED RELAXATION of deep tendon reflexes, dry coarse skin


most sensitive marker for diagnosis of hypothyroidism

serum TSH

(though, will not be elevated in patients w/ hypothyroidism due to TSH deficiency [central hypothyroidism]


valproate teratogeniticty

neural tube defects (1-3% risk)
valproate inhibits intestinal folic acid absorption


signs of duodenal atresia?

clinical hallmark: bilious vomiting w/o abdominal distension. usually noted on 1st day of life.

peristaltic waves may be visualized in abdomen & history of polyhydramnios due to failure of amniotic fluid reabsorption in distal instestine

often seen in down syndrome


death resulting from bilateral renal agenesis

death from pulmonary hypoplasia shortly after birth


ebstein's anomaly? cause?

atrialized right ventricle (downward displacement of tricuspid valve).

occurs when mom takes lithium early in pregnancy.


anaphylactic reaction to type O blood products in person w/ recurrent sinopulmonary and GI tract infections?

selective IgA deficiency.

anaphylaxis to IgA! make IgG against it. IgA = foreign


C1 esterase inhibitor deficiency

hereditary angioedema. rare. AUTOSOMAL DOMINANT. ace inhibitors are contraindicated.

C1 esterase inhibits nonspecific C1 fixation


delirium? causes?

delirium: 'waxing & waning' fluctuations in consciousness. acute, global memory impairment, visual hallucinations. 'altered sensorIUM'

reversible & commonly occurs in hospital setting

alcohol, electrolyte imbalace, iatrogenic (i.e. meds), oxygen hypoxia, uremia. trauma, infxn, posion, seizure (post-ictal)


delirium vs. dementia

onset, consciousness, course, prognosis, memory

in delirium:
acute, impaired consciousness, fluctuating symptoms, reversible, GLOBAL memory loss.

in dementia:
gradual, intact consciousness, progressive decline, usu irreversible, remote memory SPARED.
(reversible, at least partially, with: NPH, vitamin b12 deficiency, hypothyroidism, neurosyphilis, HIV)


Reye's syndrome description and pathogenesis

hepatic failure and acute encephalopathy. associated w/ use of aspirin in patients 5-14 y/o.

pathogenesis: unknown; affected children have metabolic error sensitizing to toxic effect of salicylates. especially in virally-infected cells. causes mitochondrial dysfunction.

mechanism: aspirin metabolites decrease beta-oxidation by reversible inhibition of mitochondrial enzymes.


describe lab findings & histology in reye's

vomiting, hepatomegaly. jaundice = rare.

increased ALT, AST, ammonia, bilirubin, prolonged PT and PTT.

light microscope: microvesicular steatosis. NO necrosis or inflammation.

EM: swelling, decreased mitochondria, glycogen depletion.


do not give aspirin (salicylates) to kids under..

16 y/o (except if Kawasaki)


histology of viral hepatitis

apoptosis of hepatocytes, acinar necrosis, periportal mononuclear inflammatory infiltration


liver findings in patients w/ right-sided heart failure

centrilobular congestion


histology of primary biliary cirrhosis

bile duct destruction, periductal granulomatous inflammation, bile duct proliferation


respiratory epithelium with stratified squamous epithlium

response to chronic irritation: METAPLASIA.

adaptive: resistant to irritation than columnar cells.

HOWEVER: no cilia/goblet cells: no mucociliary clearance. can lead to dysplasia (low-grade atypical cells). risk factor for carcinoma (high-grade atypia).

REVERSIBLE, can resolve upon discontinuation of smoking.


renal response to markedly narrowed renal artery (i.e. stenosis)

compensatory RENIN secretion (juxtaglomerular apparatus)

eventually: juxtaglomerular apparatus undergoes hypertrophy & hyperplasia (to make more renin).

juxtaglomerular apparatus: JG cells and macula densa

juxtaglomerular cells: modified SMOOTH MUSCLE CELLS located in alls of afferent and efferent arterioles.

macula densa: tall, narrow cells in distal tubules. monitor osmolarity and volume of urine that passes into distal tubules. pass info to JG.


juxtaglomerular apparatus (2)

juxtaglomerular cells: modified smooth muscle cells in afferent & efferent arteriole. secrete RENIN.

macula densa: tall narrow cells in distal tubules, sense osmolarity & volume in tubules


noise-induced hearing loss?

trauma to sterociliated hair cells of organ of orti. >85dB. distortion / fracture of stereocilia due to shearing forces against tectorial membrane.

loose high frequency first (4000Hz)


frequency of speech



acoustic reflex?

dampens effects of prolonged loud noise by contracting stapedius & tensor tympani.


tensor tympani & stapedius

note. paralysis of mandibular CNV3 results in hypoacussis -- complete loss of tensor tympani tone = hard to hear (even though it normal fxn dampens sounds at other extreme).

loss of stapedius (CNVII) = hyPERacussis



lies at apex of cochlea. has cells that sense rotation.


enhance LVOT in HCM by.. (3)

decreases venous return (valsalva, standing suddenly).

decreasing afterload.

increasing contractility


referral bias

/ admission rate bias. when cases & controls differ due to admission / referral processes.

i.e. enroll patients from all over nation, but use hospitalized control subjects form local institution


detection bias

a risk factor itself may lead to extensive diagnostic investigation & increase probability that disease is identified.

i.e. detecting more cancer in smokers, but smokers have more imaging surveillance due to smoking status!


sampling bias

non-random sampling of population. lead to study population having characteristics different from target population.

severely ill patients are more likely to enroll in cancer trials -- so results may not be applicable to patients w/ less advanced cancer.


lightning-related complications (5 systems)

(1) cardiac: arrest, arrhythmia
(2) neurologic: perihperal n. damage, seizure, confusion, respiratory arrest, autonomic dysfxn.
(3) dermatologic: lichtenberg figures (pathognomonic of lighting strike)
(4) MSK: rhabdomyolysis, bone fracture, compartment syndrome
(5) cataractsery (late sequelae), ruptured tympanic membrane, curling ulcers.


erythematous cutaneous marks in a fern-leaf pattern & second degree burns..

lichtenberg figures -- LIGHTNING INJURY