A 35-year-old man presents with fatigue, weight loss, and hyperpigmentation of the skin. Laboratory tests reveal hyponatremia, hyperkalemia, and low cortisol levels. What is the most likely diagnosis?
- A. Cushing's syndrome
- B. Addison's disease
- C. Hypothyroidism
- D. Pheochromocytoma
Correct Answer: B
Rationale: The most likely diagnosis is Addison's disease (Choice B) because the symptoms match adrenal insufficiency. The low cortisol levels indicate adrenal cortex dysfunction, leading to fatigue and weight loss. Hyponatremia and hyperkalemia result from mineralocorticoid deficiency. Hyperpigmentation occurs due to elevated ACTH levels stimulating melanin production in Addison's. Cushing's syndrome (Choice A) presents with high cortisol levels, opposite to the low levels seen here. Hypothyroidism (Choice C) does not typically cause hyponatremia or hyperkalemia. Pheochromocytoma (Choice D) manifests with hypertension and catecholamine excess, not seen in this case.
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A 65-year-old woman presents with difficulty swallowing, weight loss, and a history of long-standing heartburn. She has been on proton-pump inhibitors for years, but her symptoms have worsened. What is the most likely diagnosis?
- A. Peptic stricture
- B. Esophageal cancer
- C. Achalasia
- D. Esophageal spasm
Correct Answer: B
Rationale: The correct answer is B: Esophageal cancer. Given the patient's age, symptoms of difficulty swallowing and weight loss, along with a history of chronic heartburn not responding to proton-pump inhibitors, esophageal cancer is the most likely diagnosis. Esophageal cancer commonly presents with dysphagia, weight loss, and a history of chronic reflux. Peptic stricture (A) typically presents with dysphagia but is less likely given the worsening symptoms despite treatment. Achalasia (C) presents with dysphagia and regurgitation, but not typically with weight loss. Esophageal spasm (D) presents with chest pain and dysphagia, but not typically with weight loss or chronic heartburn.
The patient described in the preceding question has a positive H. pylori antibody blood test. She is compliant with the medical regimen you prescribe. Although her symptoms initially respond, she returns to see you six months later with the same symptoms. Which of the following statements is correct?
- A. She is at low risk for reinfection with H. pylori
- B. A positive serum IgG indicates that eradication of H. pylori was successful
- C. The urease breath test is an ideal test to document failure of eradication
- D. Dyspepsia typically worsens with H. pylori eradication
Correct Answer: C
Rationale: The correct answer is C because the urease breath test is the ideal test to document failure of H. pylori eradication. This test directly measures the presence of the H. pylori bacterium in the stomach by detecting the enzyme urease produced by the bacterium. If the patient still has symptoms after treatment, a positive urease breath test would indicate that the bacterium is still present, leading to treatment failure.
Choice A is incorrect because a positive antibody test does not indicate low risk for reinfection. Choice B is incorrect because a positive serum IgG may persist even after successful eradication. Choice D is incorrect because dyspepsia can improve after successful H. pylori eradication rather than worsen.
In a patient with a history of chronic iron deficiency anemia requiring a recent blood transfusion and an extensive GI work-up, which statement is true based on their medications?
- A. A dedicated small bowel series has a high likelihood of being positive
- B. 81 mg of aspirin per day decreases the benefit of using a COX II inhibitor
- C. The patient should have a provocative arteriogram with heparin infusion to identify the source of blood loss
- D. Hormonal therapy has been shown to be effective in decreasing blood loss due to arteriovenous malformations
Correct Answer: B
Rationale: The correct answer is B: 81 mg of aspirin per day decreases the benefit of using a COX II inhibitor. Aspirin, a non-selective COX inhibitor, can interfere with the action of selective COX II inhibitors by competing for the same binding site on the COX enzyme. This competition can limit the effectiveness of the COX II inhibitor in reducing inflammation and pain. This is particularly important in patients with a history of chronic iron deficiency anemia who may require NSAIDs for pain management.
Option A is incorrect because a dedicated small bowel series may not necessarily be positive for identifying the source of blood loss in this patient. Option C is incorrect as a provocative arteriogram with heparin infusion is an invasive procedure and not typically indicated as a first-line investigation for blood loss in patients with iron deficiency anemia. Option D is incorrect as hormonal therapy is not typically used to decrease blood loss from arteriovenous malformations.
A 35-year-old man presents with difficulty swallowing, weight loss, and regurgitation of undigested food. A barium swallow shows a 'bird beak' appearance of the lower esophagus. What is the most likely diagnosis?
- A. Esophageal cancer
- B. Achalasia
- C. Peptic stricture
- D. Gastroesophageal reflux disease
Correct Answer: B
Rationale: The correct answer is B: Achalasia. The presentation of difficulty swallowing, weight loss, regurgitation of undigested food, and 'bird beak' appearance on barium swallow are classic for achalasia. In achalasia, there is impaired relaxation of the lower esophageal sphincter and absent peristalsis in the esophagus. This leads to functional obstruction and dilation of the esophagus, causing the characteristic 'bird beak' appearance.
Incorrect Choices:
A: Esophageal cancer typically presents with progressive dysphagia, weight loss, and may show a mass or stricture on imaging.
C: Peptic stricture is usually seen in patients with long-standing gastroesophageal reflux disease or esophagitis. Symptoms are often related to acid reflux.
D: Gastroesophageal reflux disease commonly presents with heartburn, regurgitation, and chest pain. It does not typically cause weight loss or the 'bird
A 50-year-old man presents with severe epigastric pain radiating to his back, nausea, and vomiting. He has a history of heavy alcohol use. Laboratory tests reveal elevated serum amylase and lipase. What is the most likely diagnosis?
- A. Acute cholecystitis
- B. Peptic ulcer disease
- C. Acute pancreatitis
- D. Gastroesophageal reflux disease
Correct Answer: C
Rationale: The correct answer is C: Acute pancreatitis. The patient's symptoms of severe epigastric pain radiating to the back, along with nausea, vomiting, and a history of heavy alcohol use, are classic for acute pancreatitis. Elevated serum amylase and lipase levels further support this diagnosis, as they are key markers of pancreatic inflammation. Acute cholecystitis (A) typically presents with right upper quadrant pain and fever. Peptic ulcer disease (B) is characterized by burning epigastric pain that improves with food intake. Gastroesophageal reflux disease (D) presents with heartburn and regurgitation, not the severe symptoms seen in this case.