COMSAE 110 ACTUAL EXAM NEWEST VERSION 2026
-2027 ACTUAL QUESTION AND CORRECT DETAILED
ANSWERS RATED A GRADE.
QUESTION
A 68-year-old male is brought to the emergency department for evaluation of sudden-
onset left-sided numbness of the face and extremities. His past medical history is
significant for hypertension and type 2 diabetes mellitus. These symptoms most likely
represent a lacunar infarct of which of the following structures?
a) Basis pontis
b) Central midbrain
c) Posterior limb of the internal capsule
d) Subthalamic nucleus
e) Ventroposterior thalamus
CORRECT ANS: e) Ventroposterior thalamus
Expert Rationale
The patient's presentation of sudden-onset contralateral numbness (left-sided face and
extremities) without motor weakness is classic for a lacunar infarct affecting the
ventroposterior (VP) thalamus (option e). The VP nucleus receives somatosensory input
from the spinothalamic and medial lemniscal pathways and projects to the primary
sensory cortex. An infarct in this region results in pure sensory stroke, characterized by
contralateral hemisensory loss. The patient's risk factors (hypertension and diabetes) are
consistent with small vessel disease, which is the underlying pathology of lacunar
infarcts.
Option a is incorrect; the basis pontis contains corticospinal and corticobulbar tracts. An
infarct here would cause contralateral hemiparesis, not isolated sensory loss. Option b is
incorrect; central midbrain lesions are associated with oculomotor deficits and may
cause Weber's syndrome (ipsilateral CN III palsy with contralateral hemiparesis). Option
c is incorrect; the posterior limb of the internal capsule contains both motor and sensory
fibers; an infarct there would typically cause contralateral hemiparesis and sensory loss.
,Option d is incorrect; the subthalamic nucleus is involved in movement disorders such as
hemiballismus, not sensory deficits.
DIF: Cognitive Level: Analyze (Application/Analysis)
TOP: Neurology: Lacunar Infarcts
MSC: COMSAE 110: Neuroanatomy
QUESTION
A 36-year-old female with a three-month history of fatigue presents with multiple aches
and pains all over her body. She reports poor sleep and a lack of motivation. Physical
examination reveals multiple tender points on both sides of the body, above and below
the diaphragm. Plain film radiographs reveal no abnormalities, and rheumatological
blood tests are negative. What is the most appropriate method of diagnosis?
a) Diagnosis of exclusion
b) Electromyography
c) MRI of the brain
d) Muscle biopsy
e) Serum protein electrophoresis
CORRECT ANS: a) Diagnosis of exclusion
Expert Rationale
The patient's presentation is consistent with fibromyalgia, a condition characterized by
chronic widespread musculoskeletal pain, fatigue, sleep disturbances, and the presence
of tender points (option a). The diagnosis of fibromyalgia is clinical and is traditionally
made as a diagnosis of exclusion after other conditions with similar symptoms (e.g.,
rheumatoid arthritis, lupus, polymyalgia rheumatica) have been ruled out. The negative
rheumatological blood tests and normal imaging support this approach.
Option b is incorrect; electromyography is used to evaluate neuromuscular disorders,
not fibromyalgia. Option c is incorrect; MRI of the brain is not indicated for fibromyalgia.
Option d is incorrect; muscle biopsy is not a diagnostic tool for fibromyalgia. Option e is
,incorrect; serum protein electrophoresis is used to detect monoclonal gammopathies,
which are not associated with fibromyalgia.
DIF: Cognitive Level: Understand (Comprehension)
TOP: Rheumatology: Fibromyalgia
MSC: COMSAE 110: Rheumatology
QUESTION
A 54-year-old female presents with difficulty walking. Review of systems reveals a flu-
like illness two weeks ago. The patient reports that weakness began in her feet days ago
and now involves her legs. Physical examination reveals symmetric decreased strength in
both lower limbs and absent patellar and Achilles reflexes bilaterally. Sensation is intact.
Nerve conduction studies reveal decreased conduction velocity in the lower limbs. The
most likely pathogenesis is:
a) Autoimmune-mediated demyelination
b) Inherited deficiency of dystrophin
c) Metabolic disease of the muscle
d) Spinal cord compression from a tumor
e) Viral infection of dorsal roots
CORRECT ANS: a) Autoimmune-mediated demyelination
Expert Rationale
The patient's presentation—symmetric ascending weakness beginning in the lower
extremities, areflexia, intact sensation, and antecedent flu-like illness—is classic for
Guillain-Barré syndrome (GBS) (option a). GBS is an acute, autoimmune-mediated
demyelinating polyneuropathy that destroys the myelin sheaths of peripheral nerves,
leading to slowed nerve conduction velocities. The pathophysiology involves an
autoimmune response targeting Schwann cells, often triggered by a preceding infection.
Option b is incorrect; Duchenne muscular dystrophy is an inherited deficiency of
dystrophin and presents in childhood. Option c is incorrect; metabolic myopathies
typically present with muscle pain and weakness, not areflexia. Option d is incorrect;
, spinal cord compression would present with sensory levels and upper motor neuron
signs (hyperreflexia), not lower motor neuron signs (areflexia). Option e is incorrect; viral
infection of dorsal roots would cause radicular pain and sensory loss, not symmetric
ascending weakness.
DIF: Cognitive Level: Analyze (Application/Analysis)
TOP: Neurology: Guillain-Barré Syndrome
MSC: COMSAE 110: Neurology
QUESTION
A 24-year-old female presents with a one-month history of extreme fatigue, weakness,
and an 8-pound weight loss. Vital signs reveal blood pressure of 100/50 mmHg and
heart rate of 115 beats per minute. Laboratory studies reveal hyponatremia,
hyperkalemia, and elevated creatinine. The patient's fatigue and weakness are most
likely due to:
a) Adrenocortical insufficiency
b) Anemia
c) Diabetes mellitus
d) Hypothyroidism
CORRECT ANS: a) Adrenocortical insufficiency
Expert Rationale
This patient's presentation—fatigue, weakness, weight loss, hypotension, tachycardia,
hyponatremia, hyperkalemia, and elevated creatinine—is classic for adrenocortical
insufficiency (Addison's disease) (option a). Adrenal insufficiency leads to decreased
aldosterone (causing hyponatremia, hyperkalemia, and hypotension) and decreased
cortisol (causing fatigue, weakness, and weight loss). The elevated creatinine may
indicate prerenal azotemia due to volume depletion.
Option b is incorrect; anemia would present with fatigue but not with the specific
electrolyte abnormalities seen here. Option c is incorrect; diabetes mellitus typically
presents with hyperglycemia, polyuria, and polydipsia, not hyponatremia and
-2027 ACTUAL QUESTION AND CORRECT DETAILED
ANSWERS RATED A GRADE.
QUESTION
A 68-year-old male is brought to the emergency department for evaluation of sudden-
onset left-sided numbness of the face and extremities. His past medical history is
significant for hypertension and type 2 diabetes mellitus. These symptoms most likely
represent a lacunar infarct of which of the following structures?
a) Basis pontis
b) Central midbrain
c) Posterior limb of the internal capsule
d) Subthalamic nucleus
e) Ventroposterior thalamus
CORRECT ANS: e) Ventroposterior thalamus
Expert Rationale
The patient's presentation of sudden-onset contralateral numbness (left-sided face and
extremities) without motor weakness is classic for a lacunar infarct affecting the
ventroposterior (VP) thalamus (option e). The VP nucleus receives somatosensory input
from the spinothalamic and medial lemniscal pathways and projects to the primary
sensory cortex. An infarct in this region results in pure sensory stroke, characterized by
contralateral hemisensory loss. The patient's risk factors (hypertension and diabetes) are
consistent with small vessel disease, which is the underlying pathology of lacunar
infarcts.
Option a is incorrect; the basis pontis contains corticospinal and corticobulbar tracts. An
infarct here would cause contralateral hemiparesis, not isolated sensory loss. Option b is
incorrect; central midbrain lesions are associated with oculomotor deficits and may
cause Weber's syndrome (ipsilateral CN III palsy with contralateral hemiparesis). Option
c is incorrect; the posterior limb of the internal capsule contains both motor and sensory
fibers; an infarct there would typically cause contralateral hemiparesis and sensory loss.
,Option d is incorrect; the subthalamic nucleus is involved in movement disorders such as
hemiballismus, not sensory deficits.
DIF: Cognitive Level: Analyze (Application/Analysis)
TOP: Neurology: Lacunar Infarcts
MSC: COMSAE 110: Neuroanatomy
QUESTION
A 36-year-old female with a three-month history of fatigue presents with multiple aches
and pains all over her body. She reports poor sleep and a lack of motivation. Physical
examination reveals multiple tender points on both sides of the body, above and below
the diaphragm. Plain film radiographs reveal no abnormalities, and rheumatological
blood tests are negative. What is the most appropriate method of diagnosis?
a) Diagnosis of exclusion
b) Electromyography
c) MRI of the brain
d) Muscle biopsy
e) Serum protein electrophoresis
CORRECT ANS: a) Diagnosis of exclusion
Expert Rationale
The patient's presentation is consistent with fibromyalgia, a condition characterized by
chronic widespread musculoskeletal pain, fatigue, sleep disturbances, and the presence
of tender points (option a). The diagnosis of fibromyalgia is clinical and is traditionally
made as a diagnosis of exclusion after other conditions with similar symptoms (e.g.,
rheumatoid arthritis, lupus, polymyalgia rheumatica) have been ruled out. The negative
rheumatological blood tests and normal imaging support this approach.
Option b is incorrect; electromyography is used to evaluate neuromuscular disorders,
not fibromyalgia. Option c is incorrect; MRI of the brain is not indicated for fibromyalgia.
Option d is incorrect; muscle biopsy is not a diagnostic tool for fibromyalgia. Option e is
,incorrect; serum protein electrophoresis is used to detect monoclonal gammopathies,
which are not associated with fibromyalgia.
DIF: Cognitive Level: Understand (Comprehension)
TOP: Rheumatology: Fibromyalgia
MSC: COMSAE 110: Rheumatology
QUESTION
A 54-year-old female presents with difficulty walking. Review of systems reveals a flu-
like illness two weeks ago. The patient reports that weakness began in her feet days ago
and now involves her legs. Physical examination reveals symmetric decreased strength in
both lower limbs and absent patellar and Achilles reflexes bilaterally. Sensation is intact.
Nerve conduction studies reveal decreased conduction velocity in the lower limbs. The
most likely pathogenesis is:
a) Autoimmune-mediated demyelination
b) Inherited deficiency of dystrophin
c) Metabolic disease of the muscle
d) Spinal cord compression from a tumor
e) Viral infection of dorsal roots
CORRECT ANS: a) Autoimmune-mediated demyelination
Expert Rationale
The patient's presentation—symmetric ascending weakness beginning in the lower
extremities, areflexia, intact sensation, and antecedent flu-like illness—is classic for
Guillain-Barré syndrome (GBS) (option a). GBS is an acute, autoimmune-mediated
demyelinating polyneuropathy that destroys the myelin sheaths of peripheral nerves,
leading to slowed nerve conduction velocities. The pathophysiology involves an
autoimmune response targeting Schwann cells, often triggered by a preceding infection.
Option b is incorrect; Duchenne muscular dystrophy is an inherited deficiency of
dystrophin and presents in childhood. Option c is incorrect; metabolic myopathies
typically present with muscle pain and weakness, not areflexia. Option d is incorrect;
, spinal cord compression would present with sensory levels and upper motor neuron
signs (hyperreflexia), not lower motor neuron signs (areflexia). Option e is incorrect; viral
infection of dorsal roots would cause radicular pain and sensory loss, not symmetric
ascending weakness.
DIF: Cognitive Level: Analyze (Application/Analysis)
TOP: Neurology: Guillain-Barré Syndrome
MSC: COMSAE 110: Neurology
QUESTION
A 24-year-old female presents with a one-month history of extreme fatigue, weakness,
and an 8-pound weight loss. Vital signs reveal blood pressure of 100/50 mmHg and
heart rate of 115 beats per minute. Laboratory studies reveal hyponatremia,
hyperkalemia, and elevated creatinine. The patient's fatigue and weakness are most
likely due to:
a) Adrenocortical insufficiency
b) Anemia
c) Diabetes mellitus
d) Hypothyroidism
CORRECT ANS: a) Adrenocortical insufficiency
Expert Rationale
This patient's presentation—fatigue, weakness, weight loss, hypotension, tachycardia,
hyponatremia, hyperkalemia, and elevated creatinine—is classic for adrenocortical
insufficiency (Addison's disease) (option a). Adrenal insufficiency leads to decreased
aldosterone (causing hyponatremia, hyperkalemia, and hypotension) and decreased
cortisol (causing fatigue, weakness, and weight loss). The elevated creatinine may
indicate prerenal azotemia due to volume depletion.
Option b is incorrect; anemia would present with fatigue but not with the specific
electrolyte abnormalities seen here. Option c is incorrect; diabetes mellitus typically
presents with hyperglycemia, polyuria, and polydipsia, not hyponatremia and
