A 60-year-old man presents with difficulty swallowing. He reports that the difficulty has been present for several months and is associated with weight loss. He has a history of smoking and heavy alcohol use. On examination, he has a palpable mass in the upper abdomen. Which of the following is the most likely cause of his symptoms?

Correct Answer: A

Rationale: The most likely cause of the man's symptoms is esophageal cancer (Choice A) due to his age, symptoms of dysphagia and weight loss, history of smoking and heavy alcohol use, and the presence of a palpable mass in the upper abdomen on examination. Esophageal cancer commonly presents with difficulty swallowing, weight loss, and risk factors such as smoking and alcohol use. The palpable mass indicates a more advanced disease stage. Choice B (Achalasia) is less likely due to the presence of a palpable mass, which is not typical of achalasia. Choice C (Gastroesophageal reflux disease) typically presents with heartburn and regurgitation rather than dysphagia and weight loss. Choice D (Peptic ulcer disease) is less likely as it does not typically cause a palpable mass or significant weight loss.

Correct Answer: A

Rationale: The correct answer is A: Postural hypotension. This condition typically presents with symptoms of dizziness and fainting upon standing due to a drop in blood pressure. In this case, the blood pressure of 90/60 mm Hg indicates hypotension, which is exacerbated by changes in position. Acute myocardial infarction (B) presents with chest pain and ECG changes, not dizziness. Arrhythmia (C) can cause palpitations but not necessarily dizziness. Hyperthyroidism (D) can cause palpitations and weight loss but not typically dizziness and fainting.

Correct Answer: C

Rationale: The correct answer is C: Psoriatic arthritis. The patient's history of psoriasis is a key clue. Psoriatic arthritis commonly affects individuals with psoriasis, presenting with joint pain and swelling. Rheumatoid arthritis (choice A) typically affects multiple joints symmetrically. Osteoarthritis (choice B) is more common in older individuals and does not have a strong association with psoriasis. Gout (choice D) is characterized by sudden, severe attacks of pain, usually in the joint at the base of the big toe, and is not typically associated with psoriasis.

Correct Answer: C

Rationale: The correct answer is C: Pulmonary edema. Crackles in the lower lung fields are indicative of fluid accumulation in the alveoli, which is characteristic of pulmonary edema. This condition is commonly seen in heart failure when the heart is unable to effectively pump blood, leading to fluid backup in the lungs. Pleural effusion (A) is the accumulation of fluid in the pleural space, not in the alveoli. Pneumonia (B) typically presents with other symptoms like fever and productive cough. COPD (D) is characterized by airflow limitation and is not directly associated with crackles due to fluid accumulation.

Correct Answer: B

Rationale: The correct answer is B, dry mouth and tongue. Dehydration often leads to decreased saliva production, resulting in a dry mouth and tongue. This is a more specific and direct sign of dehydration compared to the other choices. Increased skin turgor (choice A) is a sign of dehydration but can be influenced by other factors. Bounding pulse (choice C) is a sign of fluid overload, not dehydration. Moist mucous membranes (choice D) are a normal finding and not indicative of dehydration. Overall, dry mouth and tongue are the most specific and reliable indicators of dehydration in a patient assessment.