COMSAE 116 HIGH-YIELD EXAM PREP
COMSAE 116 HIGH-YIELD EXAM PREP NEWEST 2026/2027 ACTUAL
EXAM COMPLETE 176 QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) WITH RATIONALES |ALREADY GRADED
A+||BRAND NEW VERSION!!
These questions cover a comprehensive mix of organ systems, focusing heavily on Rheumatology
and Immunology through conditions like Ankylosing Spondylitis, Sjögren syndrome, and
Polyarteritis Nodosa. They also deeply explore Genitourinary and Hematologic disorders,
featuring high-yield pathologies such as Bacterial Vaginosis, primary hyperparathyroidism, and
Hereditary Spherocytosis. Finally, the remaining test critical concepts in Respiratory medicine,
Neurology, and Infectious disease, ranging from the anatomical decompression of a tension
pneumothorax to the neurotoxin pathways of infant botulism.
Structure: 4 sections of 44 questions each
Contents
Section 1 ................................................................................................................ 2
Section 2 .............................................................................................................. 41
Section 3 .............................................................................................................. 80
Section 4 ............................................................................................................ 120
1|Page
, COMSAE 116 HIGH-YIELD EXAM PREP
Section 1
Question 1
A 32-year-old male presents to the emergency department with a 3-day history of
a painful, swollen left lower extremity. He reports returning from a 14-hour
international flight 5 days ago. Physical examination reveals unilateral calf
swelling, warmth, and erythema. A duplex ultrasound confirms an acute deep vein
thrombosis in the popliteal vein. The patient is started on an appropriate
intravenous anticoagulant. Two days later, he is found to have a normal
prothrombin time (PT) but an expectedly prolonged activated partial
thromboplastin time (aPTT). Which of the following is the primary mechanism of
action of the drug administered?
A) Direct inhibition of factor Xa
B) Direct inhibition of thrombin (Factor IIa)
C) Binding to antithrombin III to accelerate the inactivation of thrombin and
factor Xa
D) Interference with the cyclic interconversion of vitamin K
Correct Answer: C) Binding to antithrombin III to accelerate the inactivation of
thrombin and factor Xa
Rationale: The patient is presenting with a deep vein thrombosis (DVT) secondary
to prolonged immobilization during travel and was started on unfractionated
heparin (UFH). UFH is monitored using the activated partial thromboplastin time
(aPTT). The mechanism of action of UFH involves binding to antithrombin III (ATIII),
causing a conformational change that accelerates ATIII’s inherent inactivation of
coagulation factors, primarily thrombin (Factor Iia) and Factor Xa. Direct Xa
inhibitors (like rivaroxaban) and direct thrombin inhibitors (like argatroban) do not
rely on ATIII. Vitamin K antagonists (warfarin) prolong the PT/INR initially.
2|Page
, COMSAE 116 HIGH-YIELD EXAM PREP
Question 2
A 24-year-old male medical student presents to the student health clinic with a 4-
day history of a low-grade fever, sore throat, and severe fatigue. Physical
examination reveals marked bilateral posterior cervical lymphadenopathy and
splenomegaly. A peripheral blood smear demonstrates prominent atypical
lymphocytes with abundant cytoplasm that appears to “skirt” around adjacent red
blood cells. The patient’s serum is positive for heterophile antibodies. Which of
the following cellular receptors does the causative agent utilize to gain entry into
host cells?
A) CD4 receptor on helper T-lymphocytes
B) CD21 receptor on mature B-lymphocytes
C) CR3 receptor on macrophages
D) ICAM-1 receptor on respiratory epithelial cells
Correct Answer: B) CD21 receptor on mature B-lymphocytes
Rationale: This clinical picture is classic for infectious mononucleosis caused by the
Epstein-Barr virus (EBV), a double-stranded DNA herpesvirus. Key diagnostic
features include the triad of fever, pharyngitis, and posterior cervical
lymphadenopathy, accompanied by splenomegaly, atypical lymphocytes (reactive
CD8+ T-cells) on blood smear, and a positive Monospot (heterophile antibody) test.
EBV specifically infects B-lymphocytes by binding its viral glycoprotein gp350 to
the CD21 receptor (also known as Complement Receptor 2 or CR2) on the surface
of mature B-cells. CD4 is used by HIV; ICAM-1 is used by Rhinovirus.
Question 3
A 68-year-old female with a history of severe rheumatoid arthritis presents with a
2-week history of generalized weakness, a low-grade fever, and a purple, patchy
rash on her lower extremities. Laboratory analysis reveals a significant reduction
in all three blood cell lines (pancytopenia). Physical examination is remarkable for
3|Page
, COMSAE 116 HIGH-YIELD EXAM PREP
significant, non-tender splenomegaly. Rheumatoid factor and anti-cyclic
citrullinated peptide (anti-CCP) antibodies are strongly positive. Which of the
following is the most likely diagnosis?
A) Felty syndrome
B) Systemic lupus erythematosus
C) Splenic sequestration crisis
D) Drug-induced lupus erythematosus
Correct Answer: A) Felty syndrome
Rationale: Felty syndrome is a rare, severe manifestation of long-standing,
seropositive rheumatoid arthritis (RA). It is defined by the classic clinical triad of
rheumatoid arthritis, splenomegaly, and granulocytopenia/pancytopenia. The
neutropenia or pancytopenia puts these patients at a high risk for recurrent
bacterial infections and skin ulcers. While systemic lupus erythematosus (SLE) can
cause pancytopenia, the long history of severe RA and anti-CCP positivity points
directly to Felty syndrome as the underlying cause of the new-onset splenomegaly
and pancytopenia.
Question 4
A 45-year-old female presents to the clinic with a 3-month history of worsening
fatigue, cold intolerance, and weight gain despite a decreased appetite. Physical
examination reveals a diffusely enlarged, non-tender thyroid gland, delayed
relaxation of the deep tendon reflexes, and dry, coarse skin. Laboratory evaluation
confirms primary hypothyroidism with a significantly elevated TSH and low free
T4. Serum testing is highly positive for anti-thyroid peroxidase (anti-TPO)
antibodies. Which of the following histological findings is most characteristic of
this patient’s thyroid pathology?
A) Lymphocytic infiltrate with germinal centers and Hurthle cells
B) Granulomatous inflammation with multinucleated giant cells
4|Page
COMSAE 116 HIGH-YIELD EXAM PREP NEWEST 2026/2027 ACTUAL
EXAM COMPLETE 176 QUESTIONS AND CORRECT DETAILED ANSWERS
(VERIFIED ANSWERS) WITH RATIONALES |ALREADY GRADED
A+||BRAND NEW VERSION!!
These questions cover a comprehensive mix of organ systems, focusing heavily on Rheumatology
and Immunology through conditions like Ankylosing Spondylitis, Sjögren syndrome, and
Polyarteritis Nodosa. They also deeply explore Genitourinary and Hematologic disorders,
featuring high-yield pathologies such as Bacterial Vaginosis, primary hyperparathyroidism, and
Hereditary Spherocytosis. Finally, the remaining test critical concepts in Respiratory medicine,
Neurology, and Infectious disease, ranging from the anatomical decompression of a tension
pneumothorax to the neurotoxin pathways of infant botulism.
Structure: 4 sections of 44 questions each
Contents
Section 1 ................................................................................................................ 2
Section 2 .............................................................................................................. 41
Section 3 .............................................................................................................. 80
Section 4 ............................................................................................................ 120
1|Page
, COMSAE 116 HIGH-YIELD EXAM PREP
Section 1
Question 1
A 32-year-old male presents to the emergency department with a 3-day history of
a painful, swollen left lower extremity. He reports returning from a 14-hour
international flight 5 days ago. Physical examination reveals unilateral calf
swelling, warmth, and erythema. A duplex ultrasound confirms an acute deep vein
thrombosis in the popliteal vein. The patient is started on an appropriate
intravenous anticoagulant. Two days later, he is found to have a normal
prothrombin time (PT) but an expectedly prolonged activated partial
thromboplastin time (aPTT). Which of the following is the primary mechanism of
action of the drug administered?
A) Direct inhibition of factor Xa
B) Direct inhibition of thrombin (Factor IIa)
C) Binding to antithrombin III to accelerate the inactivation of thrombin and
factor Xa
D) Interference with the cyclic interconversion of vitamin K
Correct Answer: C) Binding to antithrombin III to accelerate the inactivation of
thrombin and factor Xa
Rationale: The patient is presenting with a deep vein thrombosis (DVT) secondary
to prolonged immobilization during travel and was started on unfractionated
heparin (UFH). UFH is monitored using the activated partial thromboplastin time
(aPTT). The mechanism of action of UFH involves binding to antithrombin III (ATIII),
causing a conformational change that accelerates ATIII’s inherent inactivation of
coagulation factors, primarily thrombin (Factor Iia) and Factor Xa. Direct Xa
inhibitors (like rivaroxaban) and direct thrombin inhibitors (like argatroban) do not
rely on ATIII. Vitamin K antagonists (warfarin) prolong the PT/INR initially.
2|Page
, COMSAE 116 HIGH-YIELD EXAM PREP
Question 2
A 24-year-old male medical student presents to the student health clinic with a 4-
day history of a low-grade fever, sore throat, and severe fatigue. Physical
examination reveals marked bilateral posterior cervical lymphadenopathy and
splenomegaly. A peripheral blood smear demonstrates prominent atypical
lymphocytes with abundant cytoplasm that appears to “skirt” around adjacent red
blood cells. The patient’s serum is positive for heterophile antibodies. Which of
the following cellular receptors does the causative agent utilize to gain entry into
host cells?
A) CD4 receptor on helper T-lymphocytes
B) CD21 receptor on mature B-lymphocytes
C) CR3 receptor on macrophages
D) ICAM-1 receptor on respiratory epithelial cells
Correct Answer: B) CD21 receptor on mature B-lymphocytes
Rationale: This clinical picture is classic for infectious mononucleosis caused by the
Epstein-Barr virus (EBV), a double-stranded DNA herpesvirus. Key diagnostic
features include the triad of fever, pharyngitis, and posterior cervical
lymphadenopathy, accompanied by splenomegaly, atypical lymphocytes (reactive
CD8+ T-cells) on blood smear, and a positive Monospot (heterophile antibody) test.
EBV specifically infects B-lymphocytes by binding its viral glycoprotein gp350 to
the CD21 receptor (also known as Complement Receptor 2 or CR2) on the surface
of mature B-cells. CD4 is used by HIV; ICAM-1 is used by Rhinovirus.
Question 3
A 68-year-old female with a history of severe rheumatoid arthritis presents with a
2-week history of generalized weakness, a low-grade fever, and a purple, patchy
rash on her lower extremities. Laboratory analysis reveals a significant reduction
in all three blood cell lines (pancytopenia). Physical examination is remarkable for
3|Page
, COMSAE 116 HIGH-YIELD EXAM PREP
significant, non-tender splenomegaly. Rheumatoid factor and anti-cyclic
citrullinated peptide (anti-CCP) antibodies are strongly positive. Which of the
following is the most likely diagnosis?
A) Felty syndrome
B) Systemic lupus erythematosus
C) Splenic sequestration crisis
D) Drug-induced lupus erythematosus
Correct Answer: A) Felty syndrome
Rationale: Felty syndrome is a rare, severe manifestation of long-standing,
seropositive rheumatoid arthritis (RA). It is defined by the classic clinical triad of
rheumatoid arthritis, splenomegaly, and granulocytopenia/pancytopenia. The
neutropenia or pancytopenia puts these patients at a high risk for recurrent
bacterial infections and skin ulcers. While systemic lupus erythematosus (SLE) can
cause pancytopenia, the long history of severe RA and anti-CCP positivity points
directly to Felty syndrome as the underlying cause of the new-onset splenomegaly
and pancytopenia.
Question 4
A 45-year-old female presents to the clinic with a 3-month history of worsening
fatigue, cold intolerance, and weight gain despite a decreased appetite. Physical
examination reveals a diffusely enlarged, non-tender thyroid gland, delayed
relaxation of the deep tendon reflexes, and dry, coarse skin. Laboratory evaluation
confirms primary hypothyroidism with a significantly elevated TSH and low free
T4. Serum testing is highly positive for anti-thyroid peroxidase (anti-TPO)
antibodies. Which of the following histological findings is most characteristic of
this patient’s thyroid pathology?
A) Lymphocytic infiltrate with germinal centers and Hurthle cells
B) Granulomatous inflammation with multinucleated giant cells
4|Page
