NBME CBSE ACTUAL EXAM 200 QUESTIONS AND
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
3 types of benign colonic polyps - ansHyperplastic polyps (saw-toothed
pattern)
Juvenile polyp
Peutz-Jeghers polyps
3 types of neoplastic polyps (adenoma) - ansTubular adenoma
(pedunculated, most common)
Tubulovillous adenoma (pedunculated)
Villous adenoma (sessile, most malignant potential)
6yo boy from Russia with unstable gait and incoordination for 2 weeks.
Pale, bulky stools for 4 years and two episodes of bacterial pneumonia
and chronic cough since age 1 year. 3%ile for height/weight. Neuro
exam shows ataxia, no DTRs, loss of proprioception. Stool shows inc
fat concentration. Vitamin deficient? - ansE
fragility of erythrocytes (hemolytic anemia)
muscle weakness
neurodysfunction
poor joint sensation and ataxia
6yo boy with recurrent systemic infections with Neisseria meningitidis
but healthy otherwise. What lab test is likely to be abnormal in this
child? - ansTotal hemolytic complement concentration
C5-C9 deficiency causes failure of formation of membrane attack
complex (MAC) which causes susceptibility to Neisseria
8 weeks after recovering from pneumococcal pneumonia, CXR shows
no abnormalities. What allowed this resolution to occur? -
ansMaintenance of basement membrane integrity
,NBME CBSE ACTUAL EXAM 200 QUESTIONS AND
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
14yo boy with daily headaches (bilateral aching in temples). "Not been
himself", more confused, forgetting things. Clumsy with frequent falls.
Broad-based ataxic gait. Slow to answer questions.
Chronic abuse of what substance cause these symptoms? - ansInhaled
glue
15yo girl emigrated from India and with several lesions on neck for 2
weeks. Physical exam shows hypopigmented, hypoesthetic area on
left side of forehead and 4-cm lesions on neck. Biopsy shows acid-fast
bacilli. Best explanation why the organism results in dermal rather
than visceral infections? - ansTemperature sensitivity
Mycobacterium leprae is non-motile acid-fast bacili that likes cool
temperature. Reservoirs is amadillos. Cutaneous nodules with
hypopigmentation, erythematous plaques with central
hypopigmentation, peripheral neuropathy, lion-like facies
16yo girl with intermittent fainting while standing. Plasma studies
show undetectable NE/Epi concentration and marked increase in
dopamine concentration when rising from a supine position to
standing
Deficiency in what enzyme? - ansDopamine B-hydroxylase
A rare form of dysautonomia. Dopamine is released as a false
neurotransmitter in place of NE and Epi
17yo woman just ran a marathon. 1 day later has SOB, weakness,
muscle tenderness, fever, tachypnea, edema, pulmonary crackles. Cr
4, UA with 3+ protein and 4+ hemoglobin
Release of what substance causes her symptoms? - ansMyoglobin
,NBME CBSE ACTUAL EXAM 200 QUESTIONS AND
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
Rhabdomyelysis -- Breakdown of muscles releases intracellular
contents. Myoglobin causes renal tubular obstruction causing AKI,
with proteinuria and myoglobinuria (which can be mistaken for
hemoglobinuria)
25yo F with 3-year hx of irregular menses. Menarche was at age of 14
years. PE shows increased hair growth on the face and chest. Pelvic
exam shows clitoromegaly and a normal-appearing uterus. Serum
shows increased 17-hydroxyprogesterone and androstenedione.
Deficiency of? - ans21-hydroxylase
"Congenital adrenal hyperplasia"
25yo woman 6-month history of joint pain poorly responsive to aspirin.
Physical exam: bilateral swelling of proximal interphalangeal joints,
metacarpophalangeal joints, and wrists; weakness of grasp. Small
nodules palpated beneath skin around joints of fingers. Dx? -
ansRheumatoid arthritis
32yo M with 3-month hx of swelling and breast tenderness. Receiving
thyroid hormone and steroid replacements since removal of pituitary
adenoma 2 years ago. Began hCG injections 4 months ago. Most likely
binding site of hCG causing gynecomastia? - ansTesticle --> estradiol
production
35yo man with recurrent sinusitis and bronchitis throughout his life.
One sister has similar history. Married with no children. Cardiac exam
shows PMI on the right midclavicular 4th intercostal, hepatic margin
on the left. Endoscopy shows nasal polyps, biopsy shows thickened,
ciliated, pseudostratified epithelium with small patches of squamous
metaplasia and mild lymphoid infiltration
What disease and what structure would be missing on electron
microscopy? - ansPrimary ciliary dyskinesia/Kartagener syndrome
, NBME CBSE ACTUAL EXAM 200 QUESTIONS AND
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
Dynein arms is missing or damaged --> cilia not working
Triad of: situs inversus, chronic sinusitis, bronchiectasis
For males, reduced fertility because low sperm motility
38yo M with 1-week hx of watery, itchy eyes and a runny nose.
Physical shows inflamed nasal mucosa. No congestion in lower lung.
Pharmacotherapy? - ansLoratadine
First gen H1 blocker has strong sedative action and anticholinergic
effects, and not recommended for people operating heavy
machineries. Second gen H1 blocker is non-sedative (Loratidine,
Cetirizine, Azelastine, Fexofenadine)
40yo M with extreme sensitivity to sunlight. Exposure to sun causes
formation of vesicles and blisters on skin, which takes weeks to heal.
He is diagnosed with a disorder caused by increased synthesis of
compounds in the skin that are subject to excitation by visible light.
What pathway is defective? - ansHeme synthesis
Porphyria cutanea tarda is caused by defect in uroporphyrinogen
decarboxylase in heme synthesis --> accumulation of uroporphyrin 1
Sx: blistering cutaneous photosensitivity caused by hepatotoxic
triggers (alcohol, estrogens). Most common type or porphyria
40yo M with interstitial pulmonary fibrosis has greater maximal
expiratory flow rate than predicted. Which best explains this? -
ansIncreased radial traction on airway
The connective tissue that surrounds the airways of the lungs are
called the parenchyma. This forms a sort of scaffold around the
airways, keeping them open with a force known as "radial traction".
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
3 types of benign colonic polyps - ansHyperplastic polyps (saw-toothed
pattern)
Juvenile polyp
Peutz-Jeghers polyps
3 types of neoplastic polyps (adenoma) - ansTubular adenoma
(pedunculated, most common)
Tubulovillous adenoma (pedunculated)
Villous adenoma (sessile, most malignant potential)
6yo boy from Russia with unstable gait and incoordination for 2 weeks.
Pale, bulky stools for 4 years and two episodes of bacterial pneumonia
and chronic cough since age 1 year. 3%ile for height/weight. Neuro
exam shows ataxia, no DTRs, loss of proprioception. Stool shows inc
fat concentration. Vitamin deficient? - ansE
fragility of erythrocytes (hemolytic anemia)
muscle weakness
neurodysfunction
poor joint sensation and ataxia
6yo boy with recurrent systemic infections with Neisseria meningitidis
but healthy otherwise. What lab test is likely to be abnormal in this
child? - ansTotal hemolytic complement concentration
C5-C9 deficiency causes failure of formation of membrane attack
complex (MAC) which causes susceptibility to Neisseria
8 weeks after recovering from pneumococcal pneumonia, CXR shows
no abnormalities. What allowed this resolution to occur? -
ansMaintenance of basement membrane integrity
,NBME CBSE ACTUAL EXAM 200 QUESTIONS AND
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
14yo boy with daily headaches (bilateral aching in temples). "Not been
himself", more confused, forgetting things. Clumsy with frequent falls.
Broad-based ataxic gait. Slow to answer questions.
Chronic abuse of what substance cause these symptoms? - ansInhaled
glue
15yo girl emigrated from India and with several lesions on neck for 2
weeks. Physical exam shows hypopigmented, hypoesthetic area on
left side of forehead and 4-cm lesions on neck. Biopsy shows acid-fast
bacilli. Best explanation why the organism results in dermal rather
than visceral infections? - ansTemperature sensitivity
Mycobacterium leprae is non-motile acid-fast bacili that likes cool
temperature. Reservoirs is amadillos. Cutaneous nodules with
hypopigmentation, erythematous plaques with central
hypopigmentation, peripheral neuropathy, lion-like facies
16yo girl with intermittent fainting while standing. Plasma studies
show undetectable NE/Epi concentration and marked increase in
dopamine concentration when rising from a supine position to
standing
Deficiency in what enzyme? - ansDopamine B-hydroxylase
A rare form of dysautonomia. Dopamine is released as a false
neurotransmitter in place of NE and Epi
17yo woman just ran a marathon. 1 day later has SOB, weakness,
muscle tenderness, fever, tachypnea, edema, pulmonary crackles. Cr
4, UA with 3+ protein and 4+ hemoglobin
Release of what substance causes her symptoms? - ansMyoglobin
,NBME CBSE ACTUAL EXAM 200 QUESTIONS AND
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
Rhabdomyelysis -- Breakdown of muscles releases intracellular
contents. Myoglobin causes renal tubular obstruction causing AKI,
with proteinuria and myoglobinuria (which can be mistaken for
hemoglobinuria)
25yo F with 3-year hx of irregular menses. Menarche was at age of 14
years. PE shows increased hair growth on the face and chest. Pelvic
exam shows clitoromegaly and a normal-appearing uterus. Serum
shows increased 17-hydroxyprogesterone and androstenedione.
Deficiency of? - ans21-hydroxylase
"Congenital adrenal hyperplasia"
25yo woman 6-month history of joint pain poorly responsive to aspirin.
Physical exam: bilateral swelling of proximal interphalangeal joints,
metacarpophalangeal joints, and wrists; weakness of grasp. Small
nodules palpated beneath skin around joints of fingers. Dx? -
ansRheumatoid arthritis
32yo M with 3-month hx of swelling and breast tenderness. Receiving
thyroid hormone and steroid replacements since removal of pituitary
adenoma 2 years ago. Began hCG injections 4 months ago. Most likely
binding site of hCG causing gynecomastia? - ansTesticle --> estradiol
production
35yo man with recurrent sinusitis and bronchitis throughout his life.
One sister has similar history. Married with no children. Cardiac exam
shows PMI on the right midclavicular 4th intercostal, hepatic margin
on the left. Endoscopy shows nasal polyps, biopsy shows thickened,
ciliated, pseudostratified epithelium with small patches of squamous
metaplasia and mild lymphoid infiltration
What disease and what structure would be missing on electron
microscopy? - ansPrimary ciliary dyskinesia/Kartagener syndrome
, NBME CBSE ACTUAL EXAM 200 QUESTIONS AND
ANSWERS LATEST (USMLE STEP 1) MEDICAL
EXAMINATION LATEST UPDATED MAY 2023 A+
GRADE.
Dynein arms is missing or damaged --> cilia not working
Triad of: situs inversus, chronic sinusitis, bronchiectasis
For males, reduced fertility because low sperm motility
38yo M with 1-week hx of watery, itchy eyes and a runny nose.
Physical shows inflamed nasal mucosa. No congestion in lower lung.
Pharmacotherapy? - ansLoratadine
First gen H1 blocker has strong sedative action and anticholinergic
effects, and not recommended for people operating heavy
machineries. Second gen H1 blocker is non-sedative (Loratidine,
Cetirizine, Azelastine, Fexofenadine)
40yo M with extreme sensitivity to sunlight. Exposure to sun causes
formation of vesicles and blisters on skin, which takes weeks to heal.
He is diagnosed with a disorder caused by increased synthesis of
compounds in the skin that are subject to excitation by visible light.
What pathway is defective? - ansHeme synthesis
Porphyria cutanea tarda is caused by defect in uroporphyrinogen
decarboxylase in heme synthesis --> accumulation of uroporphyrin 1
Sx: blistering cutaneous photosensitivity caused by hepatotoxic
triggers (alcohol, estrogens). Most common type or porphyria
40yo M with interstitial pulmonary fibrosis has greater maximal
expiratory flow rate than predicted. Which best explains this? -
ansIncreased radial traction on airway
The connective tissue that surrounds the airways of the lungs are
called the parenchyma. This forms a sort of scaffold around the
airways, keeping them open with a force known as "radial traction".
