USMLE Step 3: UWORLD Practice Test 2 With Questions
And Answers All Are Correct Test
3 yo M has a 8 day hx of 3-4 daily episodes of soft, *foul-smelling diarrhea*. Increased belching & Flatus,
decreased appetite but drinks liquids without difficulty. 6 yr old sister has same sx. Fam went on cruise
to Mexico last month so he tried new foods and went swimming at beach&in cruise ship pool. Went on
wkd camping trip 3 wks ago and ate the fresh fish. After vacation, he went back to reg diet fruits, veggies
7 meats. P 108, hyperactive bowel sounds. negative stool occult blood. CAUSE of sx? Correct Answer:
*giardia lamblia*
-greasy, foul-smelling diarrhea, bloating, flatus/belching, weight loss
-transmitted thru *fecal-oral route* or thru *contaminated food or water*
-ingestion of unfiltered water while *camping* or hiking
--drinking, swimming or consuming food from contaminated water
-sx DON't present ASAP b/c takes time for cysts to mature into trophozoites in host intestines
-tx: *metronidazole*
norovirus Correct Answer: -causes viral gastroenteritis
-*cruise-ship* outbreaks
-BRIEF duration: resolves within days
-*VOMITING more common*rota
rotavirus Correct Answer: *watery diarrhea* in kids age 2 and under
-within 1-2 DAYS of exposure
-also emesis, abd pain
meta-analysis Correct Answer: -combines results of *several studies* to *increase statistical power*
thru an *increased sample size*
-ideally, the results are the same as produced by single study w/larger sample size
-BUT *increase in statistical power may lead to *statistically SIGNIFICANT* effect sizes that maybe
*CLINICALLY IRRELEVANT*=detects a very small effect(eg risk ratio)--not practical
---also, *validity depends on the design*-metanalysis isn't always more valid than other study designs
cephalohematoma vs caput succedaneum Correct Answer: cephalohematoma: DOESN'T cross suture
lines & resolves within WEEKS, *can lead to jaundice* b/c RBC breakdown&Calcification after resolution-
located UNDER periosteum
Caput succedaneum: like a CAP crosses suture lines&resolves DAYS after birth-serosanuineous fluid
collection above periosteum/beneath scalp
subgaleal hemorrhage Correct Answer: -bleeding under galea aponeurotica
-fatal complication of vacuum-assisted deliveries
-rapidly expanding swelling leading to hypovolemic shock from blood loss
2 week old girl has *asymmetric gluteal skinfolds&increased # thigh creases on right>left*. what else
would be found? Correct Answer: *Apparent leg-length discrepancy* when pt lies supine w/knees
flexed: affected leg looks shorter(Galeazzi test)
DX: developmental dysplasia of hip
,-abnormal development of hip joint tht prevents femoral head from sitting properly in acetabulum
-RF: *females, breech position, FH DDH, excessively tight swaddling*
-instability during attempted dislocation&reduction if palpable clunk heard (Barlow and Ortolani
maneuvers)
who has asymmetric moro reflex? Correct Answer: erb palsy (seen in large for gestational age infants)
who has sacral dimple? Correct Answer: neural tube defect (myelomeningocele)
what's the next step after u/s shows dislocated right hip w/flat acetabulum and positive barlow and
ortolani tests? Correct Answer: *Consult orthopedic surgeon*
--when ID within first 6 months of life, treat by maintaining hip in *flexed&abducted position in Pavlik
harness for 3 months*
-when hip extension & adduction are limited, the dislocated hip is reduced and/or stabilized and normal
acetabular development is promoted
--monitor pavlik harness closely by orthopedic surgeon b/c associated risks( avascular necrosis, femoral
nerve palsy) w/excessive hip flexion & abduction
>hip radiograph if >4 months old
prognosis for development dysplasia of hip Correct Answer: *most infants who are treated early have
no long-term sequelae*
-the need for surgical correction for DDH correlates w/increased age at diagnosis: <5% of pts dx &
treated w/pavlik harness in early infancy require surgery
vestibular neuritis(labyrinthitis) Correct Answer: -*single episode* of severe vertigo that can last for
days & is self-limited
-*labyrinthitis when associated w/unilateral hearing loss*
-normal MRI
-after viral infection
-feeling of imabalnce and unsteady gait
-*positive head-thrust test*:pt focuses on examiner's nose while examiner quickly rotates their head 10-
15 degrees to the side; normally the eyes remain fixed on the target but in pt w/peripheral vestibular
d/o, the eyes initially rotate w/the head before voluntarily redirecting back to the target (corrective
saccade)
first line treatment for MDD w/psychotic features (esp if severely depressed, psychotic, suicidal, refusing
to eat &Drink) Correct Answer: ECT!!!
-not mirtazapine -its not enuf alone to treat MDD w/psychotic features -combine it w/antipsychotic
17 yo girl has 3 week hx of rhinorrhea, paroyxyms of sneezing, nasal congestion, facial itching &
Develops similar sx each spring. This yr, sx are more severe than usual &persistent. Pale nasal mucosa.
Started on the most effective single treatment but what's a complication? Correct Answer: *epistaxis*
dx: allergic rhinitis
tx: *intranasal corticosteroids* (not antihistamines)-fluticasone, mometasone, budesonide
-also give nasal saline rinses b/c they hydrate nasal mucosa &Can protect from steroid effect of epistaxis
-second line: oral antihistamines(side effects acute angle-closure glaucoma, urinary retention,
constipation, dry mouth)
, interstitial cystitis Correct Answer: idipathic bladder/suprapubic pain >=6 weeks
-worse w/full bladder
-relieved w/urination
AN active study of 30 pts w/spinal deformity underwent 3 column osteotomy procedures for deformity
correction is evaluating the following outcomes at 3,6,12 months. Research proposal was approved by
IRB but on week 2, health-related quality-of-life questionnaire which serves to evaluate additional study
outcomes is added to the protocol. What's true regarding need to resubmit study protocol to IRB?
Correct Answer: *Required b/c all modifications to an already-approved research protocol need new
IRB approval*
This includes: study design, study protocols, informed consent procedures, principal investigator
team(new research assistants)
82 yo M seen for initial physician evaluation at SNF. last colonoscopy age 70. For DM2: insulin glargine,
sitagliptin. HgbA1c 6.5%. Appropriate intervention at this time? Correct Answer: *Decrease diabetes
treatment regimen*
b/c less stringent targets (hgba1c 7-8%) for those w/*limited life expectancy*, significant comorbidity or
high risk of hypoglycemia, or w/longstanding DM w/chronic complications(nephropathy)
-*Routine colon cancer screening NOT Recommended* for asymptomatic pts w/no personal or FH of
colon cancer *past age 75 *or w/less than 10 yrs life expectancy
Tx peripartum cardiomyopathy/HF Correct Answer: lasix & *Direct acting arterial
vasodilator(hydralazine reduces afterload) & Nitrate(isosorbide mononitrate-venous dilator reduces
preload)*
-safe pregnancy meds: lasix, BB, hydralazine, nitrates, cardiac glycosides (digoxin)
teratogenic effects of ACEI/ARBs Correct Answer: fetal renal toxicity
persistent patent ductus
neonatal death
why are spironolactone(mineralocorticoid receptor antagonists) contraindicated in pregnancy? Correct
Answer: feminization of male fetus in early gestation and other endocrine problems in both male &
female fetuses in late gestation
Researchers plan to carry out a study to evaluate dynamic effects of CPAP on cognitive function and
neurocognitive architecture & Function int pts w/OSA. All eligible pts w/moderate-severe OSA will be
randomly allocated to either CPAP + supportive care group or supportive care group only by
independent statistics committee andassessed at 3,6,12 months. Participants & intervention assistants,
but not data collectors, evaluators or study statisticians will be aware of participants' intervention
assignment. What's the purpose of controlling for awareness of intervention assignment in this
protocol? Correct Answer: *maximize unbiased ascertainment of outcomes*
Ascertainment bias: when results of clinical study are distorted by knowledge of which intervention the
participants are assigned to.
allocation bias Correct Answer: results from the way subjects are assigned to treatment groups
-may occur when subjects are NONRANDOMLY assigned to treatment groups of clinical study (Physicians
may preferentially enroll sicker pts into a specific treatment group like Meredith grey with richard
webber's wife)
And Answers All Are Correct Test
3 yo M has a 8 day hx of 3-4 daily episodes of soft, *foul-smelling diarrhea*. Increased belching & Flatus,
decreased appetite but drinks liquids without difficulty. 6 yr old sister has same sx. Fam went on cruise
to Mexico last month so he tried new foods and went swimming at beach&in cruise ship pool. Went on
wkd camping trip 3 wks ago and ate the fresh fish. After vacation, he went back to reg diet fruits, veggies
7 meats. P 108, hyperactive bowel sounds. negative stool occult blood. CAUSE of sx? Correct Answer:
*giardia lamblia*
-greasy, foul-smelling diarrhea, bloating, flatus/belching, weight loss
-transmitted thru *fecal-oral route* or thru *contaminated food or water*
-ingestion of unfiltered water while *camping* or hiking
--drinking, swimming or consuming food from contaminated water
-sx DON't present ASAP b/c takes time for cysts to mature into trophozoites in host intestines
-tx: *metronidazole*
norovirus Correct Answer: -causes viral gastroenteritis
-*cruise-ship* outbreaks
-BRIEF duration: resolves within days
-*VOMITING more common*rota
rotavirus Correct Answer: *watery diarrhea* in kids age 2 and under
-within 1-2 DAYS of exposure
-also emesis, abd pain
meta-analysis Correct Answer: -combines results of *several studies* to *increase statistical power*
thru an *increased sample size*
-ideally, the results are the same as produced by single study w/larger sample size
-BUT *increase in statistical power may lead to *statistically SIGNIFICANT* effect sizes that maybe
*CLINICALLY IRRELEVANT*=detects a very small effect(eg risk ratio)--not practical
---also, *validity depends on the design*-metanalysis isn't always more valid than other study designs
cephalohematoma vs caput succedaneum Correct Answer: cephalohematoma: DOESN'T cross suture
lines & resolves within WEEKS, *can lead to jaundice* b/c RBC breakdown&Calcification after resolution-
located UNDER periosteum
Caput succedaneum: like a CAP crosses suture lines&resolves DAYS after birth-serosanuineous fluid
collection above periosteum/beneath scalp
subgaleal hemorrhage Correct Answer: -bleeding under galea aponeurotica
-fatal complication of vacuum-assisted deliveries
-rapidly expanding swelling leading to hypovolemic shock from blood loss
2 week old girl has *asymmetric gluteal skinfolds&increased # thigh creases on right>left*. what else
would be found? Correct Answer: *Apparent leg-length discrepancy* when pt lies supine w/knees
flexed: affected leg looks shorter(Galeazzi test)
DX: developmental dysplasia of hip
,-abnormal development of hip joint tht prevents femoral head from sitting properly in acetabulum
-RF: *females, breech position, FH DDH, excessively tight swaddling*
-instability during attempted dislocation&reduction if palpable clunk heard (Barlow and Ortolani
maneuvers)
who has asymmetric moro reflex? Correct Answer: erb palsy (seen in large for gestational age infants)
who has sacral dimple? Correct Answer: neural tube defect (myelomeningocele)
what's the next step after u/s shows dislocated right hip w/flat acetabulum and positive barlow and
ortolani tests? Correct Answer: *Consult orthopedic surgeon*
--when ID within first 6 months of life, treat by maintaining hip in *flexed&abducted position in Pavlik
harness for 3 months*
-when hip extension & adduction are limited, the dislocated hip is reduced and/or stabilized and normal
acetabular development is promoted
--monitor pavlik harness closely by orthopedic surgeon b/c associated risks( avascular necrosis, femoral
nerve palsy) w/excessive hip flexion & abduction
>hip radiograph if >4 months old
prognosis for development dysplasia of hip Correct Answer: *most infants who are treated early have
no long-term sequelae*
-the need for surgical correction for DDH correlates w/increased age at diagnosis: <5% of pts dx &
treated w/pavlik harness in early infancy require surgery
vestibular neuritis(labyrinthitis) Correct Answer: -*single episode* of severe vertigo that can last for
days & is self-limited
-*labyrinthitis when associated w/unilateral hearing loss*
-normal MRI
-after viral infection
-feeling of imabalnce and unsteady gait
-*positive head-thrust test*:pt focuses on examiner's nose while examiner quickly rotates their head 10-
15 degrees to the side; normally the eyes remain fixed on the target but in pt w/peripheral vestibular
d/o, the eyes initially rotate w/the head before voluntarily redirecting back to the target (corrective
saccade)
first line treatment for MDD w/psychotic features (esp if severely depressed, psychotic, suicidal, refusing
to eat &Drink) Correct Answer: ECT!!!
-not mirtazapine -its not enuf alone to treat MDD w/psychotic features -combine it w/antipsychotic
17 yo girl has 3 week hx of rhinorrhea, paroyxyms of sneezing, nasal congestion, facial itching &
Develops similar sx each spring. This yr, sx are more severe than usual &persistent. Pale nasal mucosa.
Started on the most effective single treatment but what's a complication? Correct Answer: *epistaxis*
dx: allergic rhinitis
tx: *intranasal corticosteroids* (not antihistamines)-fluticasone, mometasone, budesonide
-also give nasal saline rinses b/c they hydrate nasal mucosa &Can protect from steroid effect of epistaxis
-second line: oral antihistamines(side effects acute angle-closure glaucoma, urinary retention,
constipation, dry mouth)
, interstitial cystitis Correct Answer: idipathic bladder/suprapubic pain >=6 weeks
-worse w/full bladder
-relieved w/urination
AN active study of 30 pts w/spinal deformity underwent 3 column osteotomy procedures for deformity
correction is evaluating the following outcomes at 3,6,12 months. Research proposal was approved by
IRB but on week 2, health-related quality-of-life questionnaire which serves to evaluate additional study
outcomes is added to the protocol. What's true regarding need to resubmit study protocol to IRB?
Correct Answer: *Required b/c all modifications to an already-approved research protocol need new
IRB approval*
This includes: study design, study protocols, informed consent procedures, principal investigator
team(new research assistants)
82 yo M seen for initial physician evaluation at SNF. last colonoscopy age 70. For DM2: insulin glargine,
sitagliptin. HgbA1c 6.5%. Appropriate intervention at this time? Correct Answer: *Decrease diabetes
treatment regimen*
b/c less stringent targets (hgba1c 7-8%) for those w/*limited life expectancy*, significant comorbidity or
high risk of hypoglycemia, or w/longstanding DM w/chronic complications(nephropathy)
-*Routine colon cancer screening NOT Recommended* for asymptomatic pts w/no personal or FH of
colon cancer *past age 75 *or w/less than 10 yrs life expectancy
Tx peripartum cardiomyopathy/HF Correct Answer: lasix & *Direct acting arterial
vasodilator(hydralazine reduces afterload) & Nitrate(isosorbide mononitrate-venous dilator reduces
preload)*
-safe pregnancy meds: lasix, BB, hydralazine, nitrates, cardiac glycosides (digoxin)
teratogenic effects of ACEI/ARBs Correct Answer: fetal renal toxicity
persistent patent ductus
neonatal death
why are spironolactone(mineralocorticoid receptor antagonists) contraindicated in pregnancy? Correct
Answer: feminization of male fetus in early gestation and other endocrine problems in both male &
female fetuses in late gestation
Researchers plan to carry out a study to evaluate dynamic effects of CPAP on cognitive function and
neurocognitive architecture & Function int pts w/OSA. All eligible pts w/moderate-severe OSA will be
randomly allocated to either CPAP + supportive care group or supportive care group only by
independent statistics committee andassessed at 3,6,12 months. Participants & intervention assistants,
but not data collectors, evaluators or study statisticians will be aware of participants' intervention
assignment. What's the purpose of controlling for awareness of intervention assignment in this
protocol? Correct Answer: *maximize unbiased ascertainment of outcomes*
Ascertainment bias: when results of clinical study are distorted by knowledge of which intervention the
participants are assigned to.
allocation bias Correct Answer: results from the way subjects are assigned to treatment groups
-may occur when subjects are NONRANDOMLY assigned to treatment groups of clinical study (Physicians
may preferentially enroll sicker pts into a specific treatment group like Meredith grey with richard
webber's wife)
