, NSG 550 DiaGNoStic ReaSoNiNG examS 1–3 (WilkeS UNiveRSity) –
NeWeSt 2026 eDitioN | actUal exam QUeStioNS, coRRect aNSWeRS
& expeRt RatioNaleS | complete Np SUcceSS StUDy GUiDe |
iNStaNt pDF DoWNloaD
EXAM 1
1. A 55-year-old male presents with acute flank pain and hematuria. What is the gold standard
initial imaging test for a first-time suspected kidney stone?
A. KUB
B. Renal ultrasound
C. Non-contrast CT scan
D. Intravenous pyelography
➢ coRRect aNSWeR: C. Non-contrast CT scan – The American College of Radiology
Appropriateness Criteria designates non-contrast CT as the gold standard for initial
evaluation of suspected nephrolithiasis because it has the highest sensitivity (95-100%)
and specificity (94-100%) for detecting stones of all sizes and compositions, does not
require intravenous contrast (avoiding nephrotoxicity and allergic reactions), and can
identify alternative diagnoses such as appendicitis, diverticulitis, or pancreatic pathology;
KUB has poor sensitivity for small or radiolucent stones, ultrasound is operator-
dependent and may miss ureteral stones, and IVP has been largely replaced by CT due to
lower sensitivity and contrast risks.
2. A 65-year-old woman with a 20-year history of type 2 diabetes has a urine microalbumin-to-
creatinine ratio of 150 mcg/mg. You explain that this finding represents:
A. Normal renal function
B. Early diabetic nephropathy
C. Acute kidney injury
D. Contamination from vaginal secretions
➢ coRRect aNSWeR: B. Early diabetic nephropathy – Microalbuminuria defined as 30-
300 mcg/mg creatinine is the earliest detectable marker of diabetic kidney disease,
reflecting glomerular hyperfiltration and damage to the filtration barrier from chronic
hyperglycemia-induced oxidative stress and advanced glycation end-products; the
American Diabetes Association recommends annual screening starting at diagnosis of
, type 2 diabetes because early detection allows initiation of ACE inhibitors or ARBs
which can slow or reverse progression to macroalbuminuria (>300 mcg/mg) and reduce
the risk of declining eGFR.
3. A 60-year-old man has a PSA of 7.2 ng/mL with a free PSA of 10%. Which statement about
PSA testing is most accurate?
A. PSA is a cancer-specific marker with near-perfect sensitivity
B. A low percentage of free PSA is more concerning for prostate cancer
C. PSA levels decrease with age and prostate size
D. A PSA below 4.0 always excludes clinically significant cancer
➢ coRRect aNSWeR: B. A low percentage of free PSA is more concerning for prostate
cancer – Total PSA is composed of free (unbound) and bound (complexed to protease
inhibitors) forms; malignant prostate cells produce more bound PSA, so a lower
percentage of free PSA (<25% and especially <10%) suggests a higher likelihood of
prostate cancer, while a higher percentage of free PSA is more consistent with benign
prostatic hyperplasia; PSA is not cancer-specific and has an 80% false positive rate,
levels normally increase with age and prostate volume, and biopsy-proven cancers occur
in men with PSA below 4.0, so clinical judgment and risk factors must guide further
evaluation.
4. A 50-year-old woman with rheumatoid arthritis has a positive antinuclear antibody (ANA) test
at a titer of 1:160. This finding is best interpreted as:
A. Diagnostic for systemic lupus erythematosus
B. A non-specific finding that can occur in RA
C. Indicating active joint inflammation requiring increased methotrexate
D. A contraindication to biologic therapy
➢ coRRect aNSWeR: B. A non-specific finding that can occur in RA – ANA is an
autoantibody directed against nuclear antigens and can be positive in up to 30-40% of
patients with rheumatoid arthritis, as well as in systemic lupus erythematosus,
scleroderma, Sjögren's syndrome, mixed connective tissue disease, autoimmune hepatitis,
and even in healthy individuals (especially older adults); a positive ANA in a patient with
established RA does not automatically indicate concurrent SLE unless additional clinical
(malar rash, photosensitivity, oral ulcers, serositis, arthritis, neurologic, hematologic) and
laboratory (anti-dsDNA, anti-Smith, low complement) criteria are met; the test should be
interpreted in the full clinical context.
, 5. A 30-year-old pregnant woman at 28 weeks gestation has a TSH of 0.08 mIU/L (normal 0.3-
5.0) and a normal free T4. She reports taking biotin 10,000 mcg daily for hair health. What is the
most appropriate next step?
A. Start methimazole 5 mg daily
B. Order a radioactive iodine uptake scan
C. Discontinue biotin for 2-3 days and repeat TSH and free T4
D. Diagnose gestational transient thyrotoxicosis and observe
➢ coRRect aNSWeR: C. Discontinue biotin for 2-3 days and repeat TSH and free T4 –
High-dose biotin (vitamin B7) supplementation, often taken for hair, skin, and nail health,
causes significant interference with biotin-streptavidin immunoassays used in many
commercial TSH, free T4, free T3, and troponin assays, leading to falsely low TSH and
falsely high T4/T3 levels; patients should stop biotin for at least 2-3 days (or 5 half-lives)
before repeat testing to obtain accurate results; radioactive iodine uptake is
contraindicated during pregnancy, and treatment for hyperthyroidism should never be
initiated based on a potentially spurious lab result; gestational transient thyrotoxicosis
typically presents with low TSH and elevated free T4, not low TSH with normal free T4.
6. A 25-year-old woman presents with palpitations, tremor, heat intolerance, and weight loss. Her
TSH is <0.01 mIU/L and free T4 is 3.8 ng/dL (normal 0.8-1.8). What is the best next test to
determine the etiology of her hyperthyroidism?
A. Thyroid ultrasound
B. Radioactive iodine uptake and scan
C. Fine needle aspiration biopsy
D. Serum thyroglobulin level
➢ coRRect aNSWeR: B. Radioactive iodine uptake and scan – RAIU and scan
differentiate among causes of overt hyperthyroidism: diffuse increased uptake suggests
Graves' disease, focal increased uptake in one or more nodules suggests toxic adenoma or
toxic multinodular goiter, and very low or absent uptake suggests thyroiditis (subacute,
silent, or postpartum) or factitious thyrotoxicosis (exogenous thyroid hormone);
ultrasound is useful for evaluating nodule morphology but does not assess function; fine
needle aspiration is indicated for suspicious nodules but not for determining the cause of
hyperthyroidism; thyroglobulin is used as a tumor marker for differentiated thyroid
cancer after thyroidectomy.
NeWeSt 2026 eDitioN | actUal exam QUeStioNS, coRRect aNSWeRS
& expeRt RatioNaleS | complete Np SUcceSS StUDy GUiDe |
iNStaNt pDF DoWNloaD
EXAM 1
1. A 55-year-old male presents with acute flank pain and hematuria. What is the gold standard
initial imaging test for a first-time suspected kidney stone?
A. KUB
B. Renal ultrasound
C. Non-contrast CT scan
D. Intravenous pyelography
➢ coRRect aNSWeR: C. Non-contrast CT scan – The American College of Radiology
Appropriateness Criteria designates non-contrast CT as the gold standard for initial
evaluation of suspected nephrolithiasis because it has the highest sensitivity (95-100%)
and specificity (94-100%) for detecting stones of all sizes and compositions, does not
require intravenous contrast (avoiding nephrotoxicity and allergic reactions), and can
identify alternative diagnoses such as appendicitis, diverticulitis, or pancreatic pathology;
KUB has poor sensitivity for small or radiolucent stones, ultrasound is operator-
dependent and may miss ureteral stones, and IVP has been largely replaced by CT due to
lower sensitivity and contrast risks.
2. A 65-year-old woman with a 20-year history of type 2 diabetes has a urine microalbumin-to-
creatinine ratio of 150 mcg/mg. You explain that this finding represents:
A. Normal renal function
B. Early diabetic nephropathy
C. Acute kidney injury
D. Contamination from vaginal secretions
➢ coRRect aNSWeR: B. Early diabetic nephropathy – Microalbuminuria defined as 30-
300 mcg/mg creatinine is the earliest detectable marker of diabetic kidney disease,
reflecting glomerular hyperfiltration and damage to the filtration barrier from chronic
hyperglycemia-induced oxidative stress and advanced glycation end-products; the
American Diabetes Association recommends annual screening starting at diagnosis of
, type 2 diabetes because early detection allows initiation of ACE inhibitors or ARBs
which can slow or reverse progression to macroalbuminuria (>300 mcg/mg) and reduce
the risk of declining eGFR.
3. A 60-year-old man has a PSA of 7.2 ng/mL with a free PSA of 10%. Which statement about
PSA testing is most accurate?
A. PSA is a cancer-specific marker with near-perfect sensitivity
B. A low percentage of free PSA is more concerning for prostate cancer
C. PSA levels decrease with age and prostate size
D. A PSA below 4.0 always excludes clinically significant cancer
➢ coRRect aNSWeR: B. A low percentage of free PSA is more concerning for prostate
cancer – Total PSA is composed of free (unbound) and bound (complexed to protease
inhibitors) forms; malignant prostate cells produce more bound PSA, so a lower
percentage of free PSA (<25% and especially <10%) suggests a higher likelihood of
prostate cancer, while a higher percentage of free PSA is more consistent with benign
prostatic hyperplasia; PSA is not cancer-specific and has an 80% false positive rate,
levels normally increase with age and prostate volume, and biopsy-proven cancers occur
in men with PSA below 4.0, so clinical judgment and risk factors must guide further
evaluation.
4. A 50-year-old woman with rheumatoid arthritis has a positive antinuclear antibody (ANA) test
at a titer of 1:160. This finding is best interpreted as:
A. Diagnostic for systemic lupus erythematosus
B. A non-specific finding that can occur in RA
C. Indicating active joint inflammation requiring increased methotrexate
D. A contraindication to biologic therapy
➢ coRRect aNSWeR: B. A non-specific finding that can occur in RA – ANA is an
autoantibody directed against nuclear antigens and can be positive in up to 30-40% of
patients with rheumatoid arthritis, as well as in systemic lupus erythematosus,
scleroderma, Sjögren's syndrome, mixed connective tissue disease, autoimmune hepatitis,
and even in healthy individuals (especially older adults); a positive ANA in a patient with
established RA does not automatically indicate concurrent SLE unless additional clinical
(malar rash, photosensitivity, oral ulcers, serositis, arthritis, neurologic, hematologic) and
laboratory (anti-dsDNA, anti-Smith, low complement) criteria are met; the test should be
interpreted in the full clinical context.
, 5. A 30-year-old pregnant woman at 28 weeks gestation has a TSH of 0.08 mIU/L (normal 0.3-
5.0) and a normal free T4. She reports taking biotin 10,000 mcg daily for hair health. What is the
most appropriate next step?
A. Start methimazole 5 mg daily
B. Order a radioactive iodine uptake scan
C. Discontinue biotin for 2-3 days and repeat TSH and free T4
D. Diagnose gestational transient thyrotoxicosis and observe
➢ coRRect aNSWeR: C. Discontinue biotin for 2-3 days and repeat TSH and free T4 –
High-dose biotin (vitamin B7) supplementation, often taken for hair, skin, and nail health,
causes significant interference with biotin-streptavidin immunoassays used in many
commercial TSH, free T4, free T3, and troponin assays, leading to falsely low TSH and
falsely high T4/T3 levels; patients should stop biotin for at least 2-3 days (or 5 half-lives)
before repeat testing to obtain accurate results; radioactive iodine uptake is
contraindicated during pregnancy, and treatment for hyperthyroidism should never be
initiated based on a potentially spurious lab result; gestational transient thyrotoxicosis
typically presents with low TSH and elevated free T4, not low TSH with normal free T4.
6. A 25-year-old woman presents with palpitations, tremor, heat intolerance, and weight loss. Her
TSH is <0.01 mIU/L and free T4 is 3.8 ng/dL (normal 0.8-1.8). What is the best next test to
determine the etiology of her hyperthyroidism?
A. Thyroid ultrasound
B. Radioactive iodine uptake and scan
C. Fine needle aspiration biopsy
D. Serum thyroglobulin level
➢ coRRect aNSWeR: B. Radioactive iodine uptake and scan – RAIU and scan
differentiate among causes of overt hyperthyroidism: diffuse increased uptake suggests
Graves' disease, focal increased uptake in one or more nodules suggests toxic adenoma or
toxic multinodular goiter, and very low or absent uptake suggests thyroiditis (subacute,
silent, or postpartum) or factitious thyrotoxicosis (exogenous thyroid hormone);
ultrasound is useful for evaluating nodule morphology but does not assess function; fine
needle aspiration is indicated for suspicious nodules but not for determining the cause of
hyperthyroidism; thyroglobulin is used as a tumor marker for differentiated thyroid
cancer after thyroidectomy.
