NBME 25 2024 UPDATED EXAM QUESTIONS AND CORRECT ANSWERS |GRADED A+
1. A9-year-old boy has had alopecia and hypocalcemia since birth. His serum 1,25-dihydroxycholecalciferol concentration is within the reference range, serum 24,25-dihydroxycholecalciferol is undetectable. Serum parathyroid hormon...
1. A9-year-old boy has had alopecia and hypocalcemia since
birth. His serum 1,25-dihydroxycholecalciferol concentration is
within the reference range, serum 24,25-dihydroxycholecalciferol
is undetectable. Serum parathyroid hormone concentration is
above
the upper limit of the laboratory assay and needs to be reassayed
at a dilution. The results are pending. Which of the following is the
most likely cause of his condition?
O A) Loss-of-function mutation in the calcium-sensing receptor
B) Multiple endocrine neoplasia type I
C) Mutations inactivating the vitamin D 24-hydroxylase gene
D) Mutations inactivating the vitamin D receptor
Correct Answer: D.
Vitamin D plays a role in serum calcium and phosphate
homeostasis by promoting the intestinal absorption of calcium and
phosphate. Parathyroid hormone (PTH) also h - ANSWER ✔
2. Assuming the positive predictive value of a test is 50% and the
negative predictive value is 75%, which of the following tables are
consistent with these values?
Disease
Disease
Present
,Absent
Present
Absent
A
B
Positive
50
50
750
250
Test
Negative
250
750
50
50
Positive
250
750
50
50
Test
Negative
50
50
750
250
E Cannot be determined from data given
A)
B)
C)
D)
E)
Correct Answer: A.
,Positive predictive value (PPV) and negative predictive value
(NPV) are statistical measurements that define the proportion of
positive test results that are true positives (positive tests in
patients who have the condition) and true negatives (negative
tests in
patients without the condition). PPV is thus defined as (true
positives [TP]) / (TP + false positives [FP]) and measures the
probability of a patient having the dise - ANSWER ✔
3. A75-year-old man has decreased exercise tolerance and
occasional syncopal episodes related to exertion. Left-heart
catheterization discloses this pressure tracing (Ao -aorta; LV -left
ventricle; LA -
left atrium). The most frequently encountered mechanism
underlying this disorder is which of the following?
ЕCG
A) Amyloid deposition
150-
B) Calcification
C) Cystic medial necrosis
D) Pericardial effusion
100-
O E) Septal hypertrophy
Ao
50-
LV
LA
Time
Time-
Correct Answer: B.
The pressure tracing demonstrates a large pressure gradient
between the left ventricle and aorta during systole, which is
consistent with the diagnosis of aortic stenosis. In the setting of
aortic stenosis, the left ventricle must generate higher pressures
in order to
, overcome the opening resistance of the stenotic valve. This
increased - ANSWER ✔
4
Exam Section 1: Item 4 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
4. New reagents are being designed to treat graft-versus-host
disease in HLA-unrelated bone marrow transplant recipients.
Reagents should be designed that selectively deplete which of the
following donor cells?
A) B lymphocytes
O B) Dendritic cells
C) Macrophages
D) Neutrophils
E) T lymphocytes
Correct Answer: E.
T lymphocytes, which are responsible for the immune attack
against the recipient, should be the target of agents used to treat
graft-versus-host disease (GVHD) in HLA-unrelated bone marrow
transplant recipients. Prior to grafting of allogeneic stem cells in a
bone
marrow transplant, recipient native marrow must be completely
ablated. It is then replaced with donor marrow, which recolonizes
the marrow cavity. Successful transplantation results in
reconstitution of the immune system with the donor's i - ANSWER
✔
5
Exam Section 1: Item 5 of 50
National Board of Medical Examiners
Comprehensive Basic Science Self-Assessment
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller ProfBenjamin. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $10.49. You're not tied to anything after your purchase.
