UWorld Incorrects Flashcards
label the structures seen on a chest CT
*esophagus courses between the trachea and vertebral bodies; is typically collapsed with no visible lumen
*trachea is radiolucent (dark) due to air in the structure
anatomy of the femoral triangle (lateral to medial)
femoral NERVE (lateral)
femoral ARTERY
femoral VEIN (medial)
absolute risk reduction (ARR)
*percentage indicating the actual difference in event rate between control & treatment groups
*ARR = control rate - treatment rate
relative risk reduction (RRR)
*percentage indicating relative reduction in the treatment event rate compared to the control group
*RRR = ARR / control rate
recall: ARR = control rate - treatment rate
relative risk (RR)
*ratio of the probability of an event occurring in the treatment group compared to the control group
*RR = treatment rate / control rate
number needed to treat (NNT)
*number of individuals who need to be treated to prevent a negative outcome in 1 patient
*NNT = 1/ARR
recall: ARR = control rate - treatment rate
positive predictive value (PPV)
*represents the probability of truly having a given disease, given a positive test result
*varies with disease prevalence
*PPV = true positive / total # of positives
Trisomy 18 (Edwards syndrome) - classic findings
“PRINCE” Edward:
P - prominent occiput
R - rocker bottom feet
I - intellectual disability
N - nondisjunction
C - clenched fists with overlapping fingers
E - low set Ears
*other: micrognathia (small jaw), congenital heart disease (eg. VSD), omphalocele, myelomeningocele
*death usually occurs by age 1
Trisomy 13 (Patau syndrome) - classic findings
*severe intellectual disability
*rocker bottom feet
*microphthalmia
*microcephaly
*cleft lip/palate
*holoprosencephaly
*polydactyly
*cutis aplasia
*congenital heart disease
*polycystic kidney disease
Trisomy 21 (Down Syndrome) - class findings
*intellectual disability
*flat facies
*prominent epicanthal folds
*single palmar crease
*incurved 5th finger
*DUODENAL ATRESIA
*congenital heart disease (AVSD)
*associated with early onset Alzheimer disease
social anxiety disorder
*exaggerated fear of embarrassment in social situations (eg. public speaking, using public restrooms)
*treatment: CBT, SSRIs, SNRIs
maintenance dose formula
maintenance dose = (steady-state plasma concentration) x (clearance) x (dosing interval)
*clearance of the drug determines the dose rate required to maintain a given steady state plasma concentration
Enterobius vermicularis
*aka pinworm
*causes anal pruritus, worse at night
*most common in children aged 5-10
*dx made by visualizing eggs via tape test
*transmission = fecal-oral
*treatment: bendazoles (albendazole, mebendazole), pyrantel pamoate
duodenal atresia
*due to failure of duodenal recanalization or failure to recanalize lumen from solid cord stage
*X-ray shows double-bubble (dilated stomach, proximal duodenum)
*associated with DOWN SYNDROME
foscarnet
*viral DNA/RNA polymerase inhibitor and GIV reverse transcriptase inhibitor
*binds to pyrophosphate-binding site of enzyme
*does not require any kinase activation
*ADEs: nephrotoxicity, multiple electrolyte abnormalities can lead to seizures
brief psychotic disorder
*1 or more psychotic symptoms (delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior) lasting > 1 day and < 1 month with eventual return to premorbid functioning
schizophreniform disorder
*1 or more psychotic symptoms (delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior) lasting > 1 month but < 6 months
schizophrenia
*1 or more psychotic symptoms (delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior) lasting > 6 months
acute stress disorder
*characterized by symptoms of intrusion (eg. flashbacks), negative mood, dissociation, avoidance, and arousal (ie. PTSD symptoms) that lasts between 3 days and 1 month after exposure to a life-threatening traumatic inciting event
note - PTSD requires > 1 month for dx
adjustment disorder
*emotional or behavioral sx (anxiety, outbursts) that occur within 3 months of an identifiable psychosocial stressor (eg. divorce, illness) lasting < 6 months once the stressor has ended
conversion disorder
*unexplained loss of sensory or motor function (eg. paralysis, blindness, mutism) often following an acute stressor
*patient may be aware of but indifferent toward symptoms
*more common in females, adolescents, and young adults
somatic symptom disorder
*1+ bodily complains (eg. abdominal pain, fatigue) lasting months to years
*associated with excessive, persistent thoughts and anxiety about symptoms
*may co-occur with medical illness
illness anxiety disorder
*preoccupation with acquiring or having a serious illness, often despite medical evaluation and reassurance; minimal to no somatic symptoms
Streptococcus pneumonia
*gram-positive, lancet-shaped organism that grows in pairs (diplococci)
*major virulence factor = thick polysaccharide capsule which impedes phagocytosis and complement binding
biliary atresia
*fibro-obliterative destruction of bile ducts → cholestasis
*obstruction of extrahepatic bile ducts
*associated with absent or abnormal gallbladder on ultrasound
*often presents as a newborn with persistent jaundice after 2 weeks of life, darkening urine, acholic stools, hepatomegaly
*labs: increased DIRECT bilirubin and GGT
common complications of congenital CMV
chorioretinitis
sensorineural deafness
microcephaly
medications used for pregnancy termination
- methotrexate:
-used for ECTOPIC pregnancy
-folic acid antagonist (inhibits dihydrofolate reductase)
-preferentially destroys proliferating fetal cells - mifepristone:
-used for abortion
-partial progesterone agonist (acts as progesterone antagonist during pregnancy)
-promotes placental separation and uterine contractions - misoprostol:
-used for abortion or for inducing labor
-prostaglandin E1 agonist
-stimulates uterine contractions
measles - clinical presentation
presents with:
-fever
-cough
-rhinorrhea
-conjunctivitis
-maculopapular rash that starts on the face and spreads downward
-Koplik spots (pathognomonic for measles) are characterized by tiny white, blue, or gray lesions on buccal mucosa
antimicrobial prophylaxis for HIV patients, based on CD4 counts
1) CD4 < 200: prophylaxis with trimethoprim-sulfamethoxazole for Pneumocystis jirovecii
2) CD4 < 100: prophylaxis with TMP-SMX for Toxoplasma gondii
3) CD4 < 50: prophylaxis with azithromycin for Mycobacterium avium complex
mechanical complications of acute MI: acute or within 3-5 days
-
papillary muscle rupture/dysfunction:
-usually due to right coronary artery occlusion
-severe pulmonary edema, respiratory distress, new early systolic murmur (acute MR) hypotension/cardiogenic shock -
interventricular septum rupture:
-chest pain, new holosystolic murmur, hypotension/cardiogenic shock, step up in O2 level from RA to RV
mechanical complications of acute MI: within 5 days or up to 2 weeks
-
free wall rupture:
-usually due to LAD occlusion
-chest pain, distant heart sounds, shock with rapid progression to cardiac arrest
mechanical complications of acute MI: up to several months later
-
left ventricular aneurysm:
-heart failure, angina, and ventricular arrythmias
ventilation/perfusion (V/Q) ratios in the regions of the lungs
*both perfusion and ventilation are highest in the BASE of the lung and lowest in the APEX
*however, the variability in perfusion is greater than that of ventilation
*causing V/Q ratio to be LOWEST IN BASE and HIGHEST IN APEX
fulminant hepatitis in pregnant women
*classically associated with Hepatitis E infection
*hep E is an unenveloped, single-stranded RNA virus spread through fecal-oral route
for life-threatening disease, is it more important to have high sensitivity or high specificity of the screening test?
*high SENSITIVITY ensures that most patients with the disease will have a positive test result, so fewer cases of disease are missed
*given a test with high sensitivity, a negative result would have to rule out a diagnosis (SnNout)
common ALCOHOL withdrawal symptoms
*tremors, agitation, anxiety, delirium, psychosis
*exam findings: seizures, tachycardia, palpitations
common BENZODIAZEPINE withdrawal symptoms
*tremors, anxiety, perceptual disturbances, psychosis, insomnia
*exam findings: seizures, tachycardia, palpitations
common OPIOID withdrawal symptoms
*nausea, vomiting, abdominal cramping, diarrhea, muscle aches
*exam findings: dilated pupils, yawning, piloerection, lacrimation, hyperactive bowel sounds
common STIMULANT (cocaine, amphetamine) withdrawal symptoms
*increased appetite, hypersomnia, intense psychomotor retardation, severe depression (“crash”), vivid dreams
common NICOTINE withdrawal symptoms
*dysphoria, irritability, anxiety, increased appetite
common CANNABIS withdrawal symptoms
*irritability, anxiety, depressed mood, insomnia, decreased appetite
odds ratio calculatin
*the odds of an event is related to the probability of that event: odds = P / (1 - P)
*odds ratio = odds of exposure in cases / odds of exposure in control
stroke volume
*absolute volume of blood ejected from the left ventricle with each contraction
*SV = LVEDV - LVESV
ejection fraction
*relative volume of blood ejected from the left ventricle with each contraction (stroke volume divided by LVEDV)
*EF = (LVEDV - LVESV) / LVEDV
cardiac output
*the volume of blood ejected into the aorta per unit time
*estimated by multiplying stroke volume (LVEDV - LVESV) times heart rate
cytochrome P450 inducers
*carbamazepine
*barbiturates
*phenytoin
*rifampin
*griseofulvin
*St. John’s wort
*modafinil
*cyclophosphamide
cytochrome P450 inhibitors
*amiodarone
*cimetidine
*fluoroquinolones
*clarithromycin
*azole antifungals
*grapefruit juice
*isoniazid
*ritonavir
brain areas associated with various types of aphasia
pulsus paradoxus
*significant variation in systolic blood pressure related to the respiratory cycle (exaggerated drop in systolic BP during inspiration)
*typically present in CARDIAC TAMPONADE (associated with pericardial effusion)
false negatives & positives related to specificity and sensitivity
*rate of false negatives is the complement of sensitivity (1 - sensitivity)
*rate of false positives is the complement of specificity (1 - specificity)
osmolarity in the segments of the nephron
*ADH present (dehydrated pt): lowest osmolarity in the DCT
*ADH absent (hydrated pt): lowest osmolarity in the distal collecting duct (excreting dilute urine)
type I & type II errors related to power and statistical significance
*statistical significance is the probability of a type I error (probability of REJECTING a TRUE null hypothesis)
*the inverse of power is the probability of a type II error (finding NO EFFECT when there IS A REAL EFFECT)
effects of SRY, testosterone & DHT on male sexual differentiation
*SRY gene: produces the TESTES
*AMH: causes regression of female internal genitalia (uterus, fallopian tubes)
*testosterone: produces INTERNAL male genitalia (epididymis, vas deferens)
*DHT: produces EXTERNAL male genitalia
musculocutaneous nerve (brachial plexus)
*from C5-C7
*supplies sensory innervation to the LATERAL forearm
*supplies motor innervation to the FLEXORS of the forearm (biceps)
radial nerve (brachial plexus)
*from C5-T1
*supplies sensory innervation to the posterior arm and part of hand
*supplies motor innervation to the muscles that EXTEND the FOREARM (triceps) and fingers and SUPINATE the forearm
*vulnerable with a fracture of the shaft of the humerus
median nerve (brachial plexus)
*from C5-T1
*supplies sensory innervation to the thenar aspect of the hand (thumb, index, and middle finger)
*supplies motor innervation to the forearm pronators, the wrist/finger FLEXORS, and several finger muscles
*vulnerable with a supracondylar fracture of the humerus or entrapment of the carpal tunnel
ulnar nerve (brachial plexus)
*from C8-T1
*supplies sensory innervation to the medial digits and palm
*supplies motor innervation to medial wrist and finger flexors and intrinsic muscles of the hand on the medial side
