USMLE STEP 3 EXAM FULL
CLINICAL CASE REVIEW AND
SOLUTION GUIDE
◉ Treatment of scabies. Answer: Permethrin
◉ Treatment of scabies in HIV. Answer: Oral ivermectin
◉ Treatment of atopic dermatitis. Answer: Topical steroids
Triamcinolone
Topical tacrolimus can be used in areS such as eyelids or to avoid
long-term steroids
◉ Criteria for proteinuria (parameters) in preeclampsia. Answer:
>300 mg 24 hour
>0.3 protein/creatinine ratio
Dipstick +1 or more
Reminder preeclampsia occurs after 20 weeks and is worst if <34
weeks (admit these to hospital!)
,◉ Newborn born without iris (aniridia) next step in management.
Answer: Abdominal ultrasound for Wilm's tumor (high association)
*Continue to screen until age 8*
◉ Newborn with omphalocele screen for. Answer: Chromosmal
abnormalities 13, 18, 21
◉ Methotrexate treatment for ectopic pregnancy over laparoscopy
indications. Answer: < 3.5 cm measurement of sac
< 5000 B-hCG units
No fetal cardiac activity
◉ Implantable defibrillator indications in dilated cardiomyopathy?
When do you use a biventricular pacemaker?. Answer: Implantable-
cardioverter-defribillator should be used with EF <35%
Biventricular pace maker - use when QRS is prolonged with <35%
EF
◉ When do you use an implantable defibrillator in hypertrophic
cardiomyopathy. Answer: 1. *Syncope*
2. VT
,3. Hemodynamic instability with exercise
4. Strong family history of sudden death
5. Any prior history of cardiac arrest
◉ Hypoglycemia in TPN patient think. Answer: sepsis
◉ RDS peds treatment. Answer: 1. Oxygen with CPAP
2. Surfactant administration (lucinactant)
◉ What does VACTERL stand for?. Answer: V - vertebral defects
A - anal atresia
C - cardiac abnormalities
T - Tracheoesophageal fistula
R - renal abnormalities
L - Limb syndrome
*duodenal atresia also
◉ If there is VACTRL what test should you order to screen for the
other conditions?. Answer: 1. Echo
2. Abdominal ultrasound
3. CXR
, ◉ Preferred hypertensive agent for aortic dissection. Answer:
Esmolol or Labetalol
(add nitroprusside if necessary but it is 2nd line)
◉ What RA treatment should you use for patients that have anemia
of chronic disease?. Answer: TNF-alpha inhibitors (infliximab)
◉ Thyroid nodule with low TSH next step in management. Answer:
iodine 123 scintigraphy (hot nodules = hyperthyroidism, cold
nodules = need FNA)
◉ Thyroid nodule next step in management. Answer: Ultrasound
and TSH
DO FNA if U/S is concerning or if TSH is normal/high
◉ MS best next step in management. Answer: MRI
If equivocal do lumbar puncture of IgG olgiclonal bands (however
not necessary if MRI is abnormal)
CLINICAL CASE REVIEW AND
SOLUTION GUIDE
◉ Treatment of scabies. Answer: Permethrin
◉ Treatment of scabies in HIV. Answer: Oral ivermectin
◉ Treatment of atopic dermatitis. Answer: Topical steroids
Triamcinolone
Topical tacrolimus can be used in areS such as eyelids or to avoid
long-term steroids
◉ Criteria for proteinuria (parameters) in preeclampsia. Answer:
>300 mg 24 hour
>0.3 protein/creatinine ratio
Dipstick +1 or more
Reminder preeclampsia occurs after 20 weeks and is worst if <34
weeks (admit these to hospital!)
,◉ Newborn born without iris (aniridia) next step in management.
Answer: Abdominal ultrasound for Wilm's tumor (high association)
*Continue to screen until age 8*
◉ Newborn with omphalocele screen for. Answer: Chromosmal
abnormalities 13, 18, 21
◉ Methotrexate treatment for ectopic pregnancy over laparoscopy
indications. Answer: < 3.5 cm measurement of sac
< 5000 B-hCG units
No fetal cardiac activity
◉ Implantable defibrillator indications in dilated cardiomyopathy?
When do you use a biventricular pacemaker?. Answer: Implantable-
cardioverter-defribillator should be used with EF <35%
Biventricular pace maker - use when QRS is prolonged with <35%
EF
◉ When do you use an implantable defibrillator in hypertrophic
cardiomyopathy. Answer: 1. *Syncope*
2. VT
,3. Hemodynamic instability with exercise
4. Strong family history of sudden death
5. Any prior history of cardiac arrest
◉ Hypoglycemia in TPN patient think. Answer: sepsis
◉ RDS peds treatment. Answer: 1. Oxygen with CPAP
2. Surfactant administration (lucinactant)
◉ What does VACTERL stand for?. Answer: V - vertebral defects
A - anal atresia
C - cardiac abnormalities
T - Tracheoesophageal fistula
R - renal abnormalities
L - Limb syndrome
*duodenal atresia also
◉ If there is VACTRL what test should you order to screen for the
other conditions?. Answer: 1. Echo
2. Abdominal ultrasound
3. CXR
, ◉ Preferred hypertensive agent for aortic dissection. Answer:
Esmolol or Labetalol
(add nitroprusside if necessary but it is 2nd line)
◉ What RA treatment should you use for patients that have anemia
of chronic disease?. Answer: TNF-alpha inhibitors (infliximab)
◉ Thyroid nodule with low TSH next step in management. Answer:
iodine 123 scintigraphy (hot nodules = hyperthyroidism, cold
nodules = need FNA)
◉ Thyroid nodule next step in management. Answer: Ultrasound
and TSH
DO FNA if U/S is concerning or if TSH is normal/high
◉ MS best next step in management. Answer: MRI
If equivocal do lumbar puncture of IgG olgiclonal bands (however
not necessary if MRI is abnormal)
