Self-Assessment For COMLEX Level 1
Preparation) Question And Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A Instant Download
Question 1
A 55-year-old man with chronic smoking history presents with progressive
dyspnea and barrel chest. Which finding is most consistent with emphysema?
A. Increased FEV1/FVC ratio
B. Decreased elastic recoil of lungs
C. Increased diffusing capacity
D. Pulmonary fibrosis on imaging
Rationale:
Emphysema is characterized by destruction of alveolar walls and loss of elastic
recoil, leading to air trapping and hyperinflation. This causes decreased elastic
recoil and decreased diffusing capacity. FEV1/FVC is decreased, not increased.
Pulmonary fibrosis is a restrictive disease, not obstructive.
Question 2
A 23-year-old woman presents with exophthalmos, heat intolerance, and weight
loss. Labs show low TSH and elevated T3/T4. What is the mechanism?
,A. TSH receptor–stimulating antibodies
B. Thyroid hormone resistance
C. Iodine deficiency
D. Pituitary adenoma secreting TSH
Rationale:
Graves disease is caused by autoimmune TSH receptor–stimulating
immunoglobulins leading to increased thyroid hormone production and
suppressed TSH. Thyroid resistance would show elevated TSH. Iodine deficiency
causes hypothyroidism. TSH-secreting adenoma causes elevated TSH.
Question 3
A 65-year-old man has crushing chest pain radiating to the left arm. ECG shows ST
elevation in leads II, III, aVF. Which artery is occluded?
A. Left anterior descending
B. Left circumflex
C. Right coronary artery
D. Posterior descending from LAD
Rationale:
Inferior wall MI is typically caused by RCA occlusion. LAD causes anterior MI. LCX
causes lateral MI. PDA may arise from RCA or LCX but is not primary in this
pattern.
Question 4
A child presents with edema, proteinuria, and fatty casts in urine. Diagnosis?
A. Acute interstitial nephritis
B. Post-streptococcal glomerulonephritis
C. IgA nephropathy
D. Minimal change disease
,Rationale:
Minimal change disease is the most common cause of nephrotic syndrome in
children and shows effacement of podocyte foot processes. Other options
represent nephritic syndromes.
Question 5
A patient has resting tremor, bradykinesia, and rigidity. What is the
pathophysiology?
A. Loss of dopaminergic neurons in substantia nigra
B. Increased acetylcholine in basal ganglia
C. Demyelination of corticospinal tract
D. Cerebellar Purkinje cell loss
Rationale:
Parkinson disease is due to degeneration of dopaminergic neurons in substantia
nigra pars compacta. This reduces dopamine in the nigrostriatal pathway.
Question 6
A 30-year-old woman presents with butterfly rash and joint pain. Which antibody
is most specific?
A. Anti-Smith antibody
B. Anti-dsDNA antibody
C. Anti-histone antibody
D. Anti-centromere antibody
Rationale:
Anti-dsDNA is highly specific for SLE and correlates with disease activity. Anti-
histone is drug-induced lupus. Anti-centromere is limited scleroderma.
Question 7
, A man has hematuria and RBC casts. Post-strep infection is suspected.
Mechanism?
A. Direct bacterial invasion
B. Autoantibodies against basement membrane
C. IgA deposition in mesangium
D. Immune complex deposition in glomeruli
Rationale:
Post-streptococcal GN is due to immune complex deposition activating
complement and causing inflammation. Anti-GBM causes Goodpasture. IgA
nephropathy is Berger disease.
Question 8
A patient develops acute pancreatitis. Which enzyme rises earliest?
A. Amylase
B. Lipase
C. Trypsinogen activation
D. Elastase
Rationale:
Trypsinogen activation is the initiating event in pancreatitis. Lipase is more
specific but rises later. Amylase is less specific.
Question 9
A newborn has jaundice and high unconjugated bilirubin. Deficiency?
A. UDP-glucuronyl transferase
B. Glucuronyl transferase maturation delay
C. Hemoglobin synthesis defect
D. Bile duct obstruction