NEWEST EXAM QUESTIONS AND CORRECT DETAILED A
NEW UPDATED VERSION LATEST 2026 (100% CORRECT
VERIFIED ANSWERS) COMSAE PHASE 1 ASA 113 EXAM
ALREADY GRADED A+
Question 1
A 45-year-old man with a history of alcohol use disorder presents with confusion, ataxia, and
ophthalmoplegia. Which vitamin deficiency is most likely responsible?
A. Vitamin B1 (Thiamine)
B. Vitamin B3 (Niacin)
C. Vitamin B6 (Pyridoxine)
D. Vitamin B12 (Cobalamin)
E. Vitamin C
Answer: A
**Rationale:** The classic triad of confusion, ataxia, and ophthalmoplegia defines Wernicke
encephalopathy, caused by thiamine (vitamin B1) deficiency. This condition is commonly seen
in chronic alcoholics due to poor nutrition and impaired thiamine absorption. If untreated, it can
progress to Korsakoff syndrome with irreversible memory impairment. Thiamine is a cofactor
for several enzymes including pyruvate dehydrogenase and transketolase. Immediate
intravenous thiamine replacement is the standard treatment.
**Question 2**
A 6-year-old boy presents with recurrent respiratory infections, chronic cough, and steatorrhea.
Genetic testing reveals a mutation affecting chloride transport. Which protein is defective?
A. Dystrophin
B. Fibrillin-1
C. CFTR
D. Spectrin
E. Ankyrin
Answer: C
,**Rationale:** Cystic fibrosis results from mutations in the CFTR gene on chromosome 7,
encoding a chloride channel that regulates epithelial fluid transport. Defective chloride transport
leads to thick, viscous secretions in the lungs, pancreas, and other organs. This causes recurrent
pulmonary infections, malabsorption with steatorrhea, and failure to thrive. It is inherited in an
autosomal recessive pattern, with the most common mutation being ΔF508.
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Question 3
A 30-year-old woman with Graves disease develops eye bulging and diplopia. The
ophthalmopathy is caused by antibodies targeting which receptor?
A. TSH receptor
B. ACTH receptor
C. Insulin receptor
D. LDL receptor
E. FSH receptor
Answer: A
**Rationale:** Graves disease is an autoimmune disorder where stimulatory antibodies bind to
the TSH receptor on thyroid follicular cells, causing unregulated thyroid hormone production.
These antibodies can also cross-react with orbital fibroblast TSH receptors, leading to fibroblast
proliferation, glycosaminoglycan deposition, and inflammation that produces exophthalmos and
ophthalmopathy. This is a Type II hypersensitivity reaction.
Question 4
A patient with nephrotic syndrome has massive proteinuria. Which glomerular structure is
primarily responsible for preventing albumin filtration?
A. Podocyte slit diaphragm
B. Proximal tubule brush border
C. Mesangial matrix
D. Endothelial fenestrations
E. Basement membrane alone
Answer:A
**Rationale:** The podocyte slit diaphragm forms the final and most selective filtration barrier
in the glomerulus. It restricts albumin and other large proteins from passing into the urinary
space. Damage to podocytes (as seen in minimal change disease, FSGS, or membranous
,nephropathy) disrupts the slit diaphragm, leading to proteinuria >3.5 g/day, hypoalbuminemia,
edema, and hyperlipidemia—the hallmarks of nephrotic syndrome.
Question 5
A 55-year-old man with hypertension and diabetes develops acute kidney injury after starting
lisinopril. His serum creatinine rises from 1.0 to 2.5 mg/dL within 3 days. What is the most
likely mechanism?
A. Acute interstitial nephritis
B. Contrast-induced nephropathy
C. Prerenal azotemia from efferent arteriolar dilation in renal artery stenosis
D. Acute tubular necrosis
E. Obstructive uropathy
Answer: C
**Rationale:** In patients with bilateral renal artery stenosis, glomerular filtration is
maintained by angiotensin II-mediated efferent arteriolar constriction. ACE inhibitors (like
lisinopril) dilate the efferent arteriole, decreasing intraglomerular pressure and reducing GFR,
leading to acute kidney injury. This is not a true nephrotoxicity but a hemodynamic effect that
typically reverses with drug discontinuation.
Question 6
A 22-year-old woman presents with primary amenorrhea. She has normal breast development,
scant pubic hair, and a blind-ending vagina. Imaging shows an absent uterus. What is the most
likely diagnosis?
A. Androgen insensitivity syndrome
B. Müllerian agenesis (MRKH syndrome)
C. Turner syndrome
D. Kallmann syndrome
E. Polycystic ovary syndrome
Answer: B
**Rationale:** Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is characterized by
congenital absence of the uterus and upper vagina in a female with normal ovaries and
secondary sexual characteristics. It results from Müllerian duct agenesis. Unlike androgen
insensitivity syndrome (which has XY karyotype and testes), MRKH patients have XX
karyotype and normal female external genitalia except for vaginal agenesis.
, Question 7
A 28-year-old man with acute right testicular pain and nausea has a high-riding testis with
absent cremasteric reflex. What is the most appropriate next step?
A. Urinalysis and antibiotics
B. Scrotal ultrasound with Doppler
C. Immediate surgical exploration
D. NSAIDs and scrotal elevation
E. CT abdomen and pelvis
Answer: C
**Rationale:** Testicular torsion is a urological emergency requiring immediate surgical
exploration to salvage the testis. The salvage rate is 90-100% if detorsion occurs within 4-6
hours; after 12 hours, salvage drops significantly. The classic presentation includes acute severe
pain, high-riding testis, horizontal lie, and absent cremasteric reflex. Imaging should not delay
surgical intervention in typical cases.
Question 8
A 62-year-old woman with COPD presents with worsening dyspnea and a nonproductive
cough. She has a 50-pack-year smoking history. Chest CT shows a right hilar mass with
mediastinal lymphadenopathy. Which diagnosis is most likely?
A. Small cell lung cancer
B. Sarcoidosis
C. Tuberculosis
D. Pulmonary embolism
E. Adenocarcinoma
Answer:A
Rationale: Small cell lung cancer (SCLC) is strongly associated with heavy smoking and
typically presents as a central hilar mass with bulky mediastinal lymphadenopathy. It is highly
aggressive, often metastasizes early, and is frequently associated with paraneoplastic syndromes
(e.g., SIADH, Lambert-Eaton syndrome). Unlike non-small cell lung cancers, SCLC is
generally not amenable to surgical resection and is treated primarily with chemotherapy and
radiation.
Question 9