A 45-year-old woman with occasional indigestion has had episodes of chest pain and dysphagia to both solids and liquids. An upper GI series and EGD fail to disclose any structural abnormalities. What is the most appropriate initial therapy?

Correct Answer: B

Rationale: The correct answer is B: Proton pump inhibitor. In this case, the patient's symptoms of chest pain, dysphagia to solids and liquids, and indigestion suggest possible gastroesophageal reflux disease (GERD). A proton pump inhibitor helps reduce gastric acid production, alleviating symptoms and potentially healing any esophageal damage caused by reflux. This is the most appropriate initial therapy as it targets the underlying cause. A: Sucralfate is a cytoprotective agent that may help with mucosal protection but does not address acid suppression, which is crucial in GERD. C: Prokinetic agents enhance gastrointestinal motility and are not the first-line treatment for GERD. D: Benzodiazepines are not indicated for the treatment of GERD and do not address the underlying acid reflux issue.

Correct Answer: B

Rationale: The correct answer is B: Endoscopic balloon dilatation. This is the best therapy for a 65-year-old man with symptoms of regurgitation, chest pain, dysphagia, weight loss, dilated esophagus, and an absent gastric air bubble on CXR because these symptoms suggest achalasia, a motility disorder of the esophagus. Endoscopic balloon dilatation helps to disrupt the lower esophageal sphincter muscle, relieving symptoms and improving esophageal emptying. Proton-pump inhibitors (A) are used for acid-related conditions, not for achalasia. Sucralfate (C) is a mucosal protective agent and not indicated for achalasia. Esophageal resection (D) is a more invasive option and usually reserved for severe cases or when other treatments have failed.

Correct Answer: B

Rationale: The correct answer is B: Irritable bowel syndrome (IBS). The key clues in the question are chronic constipation, bloating, abdominal pain relieved with defecation, and absence of alarming symptoms. These symptoms align with the Rome IV criteria for IBS. Inflammatory bowel disease (A) typically presents with more severe symptoms, including weight loss and blood in stools. Celiac disease (C) is associated with malabsorption symptoms and autoimmune features, not typically seen in this case. Lactose intolerance (D) presents with symptoms after consuming dairy, which is not mentioned in the patient's history. Therefore, based on the clinical presentation and exclusion of other conditions, the most likely diagnosis is IBS.

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.

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