NBME 26 EXAM UPDATED QUESTIONS
AND CORRECT ANSWERS.
Paresthesias - ANS abnormal sensation (e.g., tingling, prickling, "pins and needles")
false positives and false negatives –
placenta accreta - ANS A rare disorder in which the placenta is directly adherent to the
myometrium (without penetrating) instead of the decidua basalis. Results in delayed separation
and/or placental retention as well as postpartum hemorrhage. The most important risk factors
for placenta accreta are a previous C-section and placenta previa.
-risk factors include: prior uterine instrumentation (including ceserean delivery), increased
maternal age, placenta previa, and pultiparity.
given the high risk of morbidity and mortality, elective surgical delivery at 34 to 36 weeks is
recommended.
leiomyomata uteri - ANS (uterine fibroids)
benign tumors of the uterus, which can present with abnormal uterine bleeding and pelvic pain.
however, they are more common in older women and are associated w an irregular shaped
uterus on physical exam.
Monobactams - ANS inhibit transpeptidation by inhibiting penicillin-binding protein 3
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,antimycin A - ANS inhibits complex III of the electron transport chain
cyanide, monoxide, azides -- electron transport chain inhibitors - ANS inhibit complex IV
normal alveolar-arterial gradient (a/A gradient) - ANS 5-10 mmHg
Baclofen - ANS a GABAb receptor agonist, which hyperpolarized muscle cells and relieves
muscle spasticity
Bacteroides fragilis - ANS an anaerobic, gram-negative bacillus and a normal component of
the gastrointestinal microbiota.
it only results in infections when displaced from the colon, such as following surgery, rupture,
or trauma, where is has the potential to cause bacteremia, intra-abdominal infections,
peritonitis, and subcutaneous abscesses.
Bacterial vaginosis - ANS is caused by the vaginal overgrowth of Gardnerella vaginialis, a
gram-variable, facultative anaerobe.
It presents with gray, thin, malodorous vaginal discharge, a vaginal pH greater than 4.5, a fishy
odor upon KOH testing, and clue cells on microscopy
Glucagonoma - ANS a rare functional malignancy that secretes glucagon, which raises blood
glucose.
Glucagon acts on hepatocytes via a cAMP pathway activating protein kinase A that ends in the
activation of glycogen phosphorylase, with release of glucose monomers in the serum.
When glycogen stores are exhausted, the body relies on the breakdown of fat through beta
oxidation of fatty acids to provide energy.
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,-- occurs in mitochondria of the cell
Carnitine acetyltransferase - ANS a transmembrane protein found on the surface of
mitochondria in liver, muscle, and brain, and catalyzes the bond between acyl-CoA and
carnitine, which permits the long-chain fatty acid to translocate into the mitochondria matrix
where beta-oxidation (breakdown of fatty acid) can occur.
Renal tubular acidosis - ANS A normal anion gap (hyperchloremic) metabolic acidosis in the
presence of normal or almost normal renal function. The various types of RTA include proximal
tubular bicarbonate wasting (type II), distal tubular acid secretion (type I), very rarely carbonic
anhydrase deficiency (type III), and aldosterone deficiency/resistance (type IV). Renal tubular
acidosis arises as a result of defects in the tubular transport of HCO3- and/or H+. Most forms of
RTA are asymptomatic although, rarely, life-threatening electrolyte imbalances can occur.
Salicylate poisoning - ANS initially results in a respiratory alkalosis from the stimulation of
respiratory centers causing hyperventilation.
Subsequently, it results in the development of a delayed anion gap metabolic acidosis
secondary to its decoupling effects on the electron transport chain, resulting in increased
anaerobic metabolism and the production of lactate and ketoacids.
ansa cervicalis - ANS a loop of nerves in the anterior neck that originate from the spinal
nerve roots C1-C3.
the inferior root is formed by the fibers of C2 and C3 and provides branches to the inferior
portion of the omohyoid, stenothyroid, and sternohyoid muscles.
the phrenic nerve - ANS arises from the cervical roots C3-C5 and provides motor innervation
to the diaphragm.
it also provides sensory innervation to the mediastinal pleura and the pericardium
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, phrenic nerve injury can occur during cardiothoracic surgery or thoracic or cervical trauma and
can lead to diaphragmatic paralysis.
developing 20-month old child can typically walk up stairs (and may be able to run), stack
several blocks, and use 100 or more vocabulary words, and play pretend. - ANS aggressive,
impulsive behavior is not uncommon, and cooperative play does not typically develop until the
age of 4 years.
Osteoarthritis - ANS the most common disease of joints in humans.
It affects 60% to 80% of adults over the age of 65.
it is characterized by global degeneration of a joint with fraying, fibrillation, and degradation of
cartilage, thickening of the subchondral plate w sclerotic bone, and SUBCHONDRAL CYSTS due
to inflammation of synovial fluid into the bone.
Arthrocentesis typically demonstrates few leukocytes, normal appearance, and normal glucose.
jejunum - ANS possesses several characteristic features, including prominent plicae circularis,
which lends the jejunum an increased mucosal surface area and feathered appearance w oral
contrast material
-also demonstrates a large caliber, thicker muscular walls, longer vasa rectae, and fever arcades
congenital adrenal hyperplasia - ANS results from a defect in adrenal steroid biosynthesis.
its most common form, 21-hydroxylase deficiency, presents with salt-wasting in infants or
precocious puberty in children.
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AND CORRECT ANSWERS.
Paresthesias - ANS abnormal sensation (e.g., tingling, prickling, "pins and needles")
false positives and false negatives –
placenta accreta - ANS A rare disorder in which the placenta is directly adherent to the
myometrium (without penetrating) instead of the decidua basalis. Results in delayed separation
and/or placental retention as well as postpartum hemorrhage. The most important risk factors
for placenta accreta are a previous C-section and placenta previa.
-risk factors include: prior uterine instrumentation (including ceserean delivery), increased
maternal age, placenta previa, and pultiparity.
given the high risk of morbidity and mortality, elective surgical delivery at 34 to 36 weeks is
recommended.
leiomyomata uteri - ANS (uterine fibroids)
benign tumors of the uterus, which can present with abnormal uterine bleeding and pelvic pain.
however, they are more common in older women and are associated w an irregular shaped
uterus on physical exam.
Monobactams - ANS inhibit transpeptidation by inhibiting penicillin-binding protein 3
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
,antimycin A - ANS inhibits complex III of the electron transport chain
cyanide, monoxide, azides -- electron transport chain inhibitors - ANS inhibit complex IV
normal alveolar-arterial gradient (a/A gradient) - ANS 5-10 mmHg
Baclofen - ANS a GABAb receptor agonist, which hyperpolarized muscle cells and relieves
muscle spasticity
Bacteroides fragilis - ANS an anaerobic, gram-negative bacillus and a normal component of
the gastrointestinal microbiota.
it only results in infections when displaced from the colon, such as following surgery, rupture,
or trauma, where is has the potential to cause bacteremia, intra-abdominal infections,
peritonitis, and subcutaneous abscesses.
Bacterial vaginosis - ANS is caused by the vaginal overgrowth of Gardnerella vaginialis, a
gram-variable, facultative anaerobe.
It presents with gray, thin, malodorous vaginal discharge, a vaginal pH greater than 4.5, a fishy
odor upon KOH testing, and clue cells on microscopy
Glucagonoma - ANS a rare functional malignancy that secretes glucagon, which raises blood
glucose.
Glucagon acts on hepatocytes via a cAMP pathway activating protein kinase A that ends in the
activation of glycogen phosphorylase, with release of glucose monomers in the serum.
When glycogen stores are exhausted, the body relies on the breakdown of fat through beta
oxidation of fatty acids to provide energy.
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
,-- occurs in mitochondria of the cell
Carnitine acetyltransferase - ANS a transmembrane protein found on the surface of
mitochondria in liver, muscle, and brain, and catalyzes the bond between acyl-CoA and
carnitine, which permits the long-chain fatty acid to translocate into the mitochondria matrix
where beta-oxidation (breakdown of fatty acid) can occur.
Renal tubular acidosis - ANS A normal anion gap (hyperchloremic) metabolic acidosis in the
presence of normal or almost normal renal function. The various types of RTA include proximal
tubular bicarbonate wasting (type II), distal tubular acid secretion (type I), very rarely carbonic
anhydrase deficiency (type III), and aldosterone deficiency/resistance (type IV). Renal tubular
acidosis arises as a result of defects in the tubular transport of HCO3- and/or H+. Most forms of
RTA are asymptomatic although, rarely, life-threatening electrolyte imbalances can occur.
Salicylate poisoning - ANS initially results in a respiratory alkalosis from the stimulation of
respiratory centers causing hyperventilation.
Subsequently, it results in the development of a delayed anion gap metabolic acidosis
secondary to its decoupling effects on the electron transport chain, resulting in increased
anaerobic metabolism and the production of lactate and ketoacids.
ansa cervicalis - ANS a loop of nerves in the anterior neck that originate from the spinal
nerve roots C1-C3.
the inferior root is formed by the fibers of C2 and C3 and provides branches to the inferior
portion of the omohyoid, stenothyroid, and sternohyoid muscles.
the phrenic nerve - ANS arises from the cervical roots C3-C5 and provides motor innervation
to the diaphragm.
it also provides sensory innervation to the mediastinal pleura and the pericardium
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
, phrenic nerve injury can occur during cardiothoracic surgery or thoracic or cervical trauma and
can lead to diaphragmatic paralysis.
developing 20-month old child can typically walk up stairs (and may be able to run), stack
several blocks, and use 100 or more vocabulary words, and play pretend. - ANS aggressive,
impulsive behavior is not uncommon, and cooperative play does not typically develop until the
age of 4 years.
Osteoarthritis - ANS the most common disease of joints in humans.
It affects 60% to 80% of adults over the age of 65.
it is characterized by global degeneration of a joint with fraying, fibrillation, and degradation of
cartilage, thickening of the subchondral plate w sclerotic bone, and SUBCHONDRAL CYSTS due
to inflammation of synovial fluid into the bone.
Arthrocentesis typically demonstrates few leukocytes, normal appearance, and normal glucose.
jejunum - ANS possesses several characteristic features, including prominent plicae circularis,
which lends the jejunum an increased mucosal surface area and feathered appearance w oral
contrast material
-also demonstrates a large caliber, thicker muscular walls, longer vasa rectae, and fever arcades
congenital adrenal hyperplasia - ANS results from a defect in adrenal steroid biosynthesis.
its most common form, 21-hydroxylase deficiency, presents with salt-wasting in infants or
precocious puberty in children.
4 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED
