Usmle Step 3 Exam Questions And Correct
Answers 2024
When would you order a head CT with or without contrast? -
ANSWER--With - looks for abscesses or intracranial masses
WITHOUT - looks for acute bleeding which appears white. Contrast
also appears white and can obscure bleeding. Like in intracranial
hemorrhage
Parents bring teen daughter to ED for cutting herself. No intent to
commit suicide per daughter. Does she require hospitalization while you
work her up for safety reasons? - ANSWER--NO. There is no intent to
commit suicide in curing disorders. Just done to cope w/emotions. Pt
will need full psych work up.
Metzner's index - ANSWER--MCV/RBC. Helps to differentiate IDA
from beta-thalassemia.
Alpha or Beta-thalassemia if <13
IDA if > 13
The 4 types of shock and how they affect RAP, PCWP, CI, SVR -
ANSWER--
Explain what SPIN and SNOUT mean for specificity and sensitivity -
ANSWER--Specificity = TN/(TN+FP)
, Usmle Step 3 Exam Questions And Correct
Answers 2024
- SP-P-IN - if a test is positive for a disease then it rules IN that disease.
Use a highly specific test after a screening test to confirm that the person
actually has that disease
- low rate of false positives
Sensitivity = TP/(TP+FN)
- SN-N-OUT - if a test is negative for a disease then it rules OUT that
disease. Use a highly sensitive test on screening tests to rule out diseases
- low rate of false negatives
what is the formula for anion gap? what is normal anion gap? -
ANSWER--Na+ - (Cl- + HCO3-)
What is the order for family members designated as surrogate? -
ANSWER--Spouse, adult children, parent, adult sibling, nearest living
relative, close friend
Define: Hirsutism - ANSWER--Hirsutism (HUR-soot-iz-um) is a
condition in women that results in excessive growth of dark or coarse
hair in a male-like pattern
What is the normal range for bicarbonate? - ANSWER--22-28
, Usmle Step 3 Exam Questions And Correct
Answers 2024
How can you tell the difference btw A fib w/RVR and multifocal atrial
tachycardia? - ANSWER--Both are narrow complex tachycardias
(QRS<120 bc atrial) w/irregular R-R intervals
AFRVR - No P waves
MAT - ≥3 different types of P waves seen, HR>100
How can you tell if a question is asking you to calculate the relative
risk? The relative risk reduction? Or the absolute risk reduction? -
ANSWER--If the question says "What is the reduction in risk?" then it
wants the RRR.
If the question says "What is the magnitude of risk between these two
treatment groups?" then it wants RR
- RR = risk in exposed group/risk in control group
If the question says "What is the ARR?" Then it wants ARR
What is the mechanism behind tertiary hyperparathyroidism and what is
the treatment? - ANSWER--- Occurs in CKD and renal osteodystrophy
when you have inability to excrete phosphate and inability to convert
inactive vitamin D3 to active 1,25 dihydroxyvitamin D resulting in
hypercalcemia due to bone losses of Ca2+
, Usmle Step 3 Exam Questions And Correct
Answers 2024
- Initially you start making more PTH in response to hypocalcemia and
hyperphosphatemia. Then as Ca2+ and PO43- increase you have
uncontrolled secretion of PTH and elevation in Ca2+ and PO43-
- The only treatment is PARATHYROIDECTOMY bc the parathyroid
will just continue making PTH forever. A renal transplant will not fix
this
Which fracture happens from falling on flexion vs extension of the
wrist? - ANSWER--Flexion - bending wrist forward. Smith fracture.
Extension - falling on an outstretched hand. They will term this "tripping
and falling forward", they don't say outstretched hand, you are to assume
it. Colles fracture and Ulnar styloid fracture
In a septic patient with hyperglycemia how can you tell if the
hyperglycemia is due to undiagnosed DM? What is another cause of
hyperglycemia in these patients? - ANSWER--- Septic patients often
have high BG bc of elevated cortisol release, pro-inflammatory
cytokines and catecholamine release but they may not actually have DM.
This is called STRESS HYPERGLYCEMIA
- If the pt has random BG >200 + signs of hyperglycemia like polyuria,
polydipsia, weight loss (in children w/DM1), polyphagia OR HbA1c ≥
6.5 OR fasting plasma glucose >126 OR oral glucose tolerance test 2 hr
later w/BG>200 then this is DM
- Always check an A1c and this will tell you if there is a chronic
elevation in BG signifying undx'd DM1 or 2
Answers 2024
When would you order a head CT with or without contrast? -
ANSWER--With - looks for abscesses or intracranial masses
WITHOUT - looks for acute bleeding which appears white. Contrast
also appears white and can obscure bleeding. Like in intracranial
hemorrhage
Parents bring teen daughter to ED for cutting herself. No intent to
commit suicide per daughter. Does she require hospitalization while you
work her up for safety reasons? - ANSWER--NO. There is no intent to
commit suicide in curing disorders. Just done to cope w/emotions. Pt
will need full psych work up.
Metzner's index - ANSWER--MCV/RBC. Helps to differentiate IDA
from beta-thalassemia.
Alpha or Beta-thalassemia if <13
IDA if > 13
The 4 types of shock and how they affect RAP, PCWP, CI, SVR -
ANSWER--
Explain what SPIN and SNOUT mean for specificity and sensitivity -
ANSWER--Specificity = TN/(TN+FP)
, Usmle Step 3 Exam Questions And Correct
Answers 2024
- SP-P-IN - if a test is positive for a disease then it rules IN that disease.
Use a highly specific test after a screening test to confirm that the person
actually has that disease
- low rate of false positives
Sensitivity = TP/(TP+FN)
- SN-N-OUT - if a test is negative for a disease then it rules OUT that
disease. Use a highly sensitive test on screening tests to rule out diseases
- low rate of false negatives
what is the formula for anion gap? what is normal anion gap? -
ANSWER--Na+ - (Cl- + HCO3-)
What is the order for family members designated as surrogate? -
ANSWER--Spouse, adult children, parent, adult sibling, nearest living
relative, close friend
Define: Hirsutism - ANSWER--Hirsutism (HUR-soot-iz-um) is a
condition in women that results in excessive growth of dark or coarse
hair in a male-like pattern
What is the normal range for bicarbonate? - ANSWER--22-28
, Usmle Step 3 Exam Questions And Correct
Answers 2024
How can you tell the difference btw A fib w/RVR and multifocal atrial
tachycardia? - ANSWER--Both are narrow complex tachycardias
(QRS<120 bc atrial) w/irregular R-R intervals
AFRVR - No P waves
MAT - ≥3 different types of P waves seen, HR>100
How can you tell if a question is asking you to calculate the relative
risk? The relative risk reduction? Or the absolute risk reduction? -
ANSWER--If the question says "What is the reduction in risk?" then it
wants the RRR.
If the question says "What is the magnitude of risk between these two
treatment groups?" then it wants RR
- RR = risk in exposed group/risk in control group
If the question says "What is the ARR?" Then it wants ARR
What is the mechanism behind tertiary hyperparathyroidism and what is
the treatment? - ANSWER--- Occurs in CKD and renal osteodystrophy
when you have inability to excrete phosphate and inability to convert
inactive vitamin D3 to active 1,25 dihydroxyvitamin D resulting in
hypercalcemia due to bone losses of Ca2+
, Usmle Step 3 Exam Questions And Correct
Answers 2024
- Initially you start making more PTH in response to hypocalcemia and
hyperphosphatemia. Then as Ca2+ and PO43- increase you have
uncontrolled secretion of PTH and elevation in Ca2+ and PO43-
- The only treatment is PARATHYROIDECTOMY bc the parathyroid
will just continue making PTH forever. A renal transplant will not fix
this
Which fracture happens from falling on flexion vs extension of the
wrist? - ANSWER--Flexion - bending wrist forward. Smith fracture.
Extension - falling on an outstretched hand. They will term this "tripping
and falling forward", they don't say outstretched hand, you are to assume
it. Colles fracture and Ulnar styloid fracture
In a septic patient with hyperglycemia how can you tell if the
hyperglycemia is due to undiagnosed DM? What is another cause of
hyperglycemia in these patients? - ANSWER--- Septic patients often
have high BG bc of elevated cortisol release, pro-inflammatory
cytokines and catecholamine release but they may not actually have DM.
This is called STRESS HYPERGLYCEMIA
- If the pt has random BG >200 + signs of hyperglycemia like polyuria,
polydipsia, weight loss (in children w/DM1), polyphagia OR HbA1c ≥
6.5 OR fasting plasma glucose >126 OR oral glucose tolerance test 2 hr
later w/BG>200 then this is DM
- Always check an A1c and this will tell you if there is a chronic
elevation in BG signifying undx'd DM1 or 2
