A 44-year-old obese woman complains of abdominal pain. What finding indicates acute cholecystitis?

A positive Murphy's sign is a key indication of acute cholecystitis. This sign is assessed during a physical examination where the clinician palpates the right upper quadrant while asking the patient to take a deep breath. If the patient experiences pain and abruptly stops inhaling due to this discomfort, it suggests the presence of gallbladder inflammation, which is characteristic of acute cholecystitis.

This finding is particularly significant in this scenario because acute cholecystitis typically occurs due to obstruction of the cystic duct, often by gallstones, leading to irritation and inflammation of the gallbladder. The positive Murphy's sign effectively reflects the acute nature of this condition and helps differentiate it from other causes of abdominal pain.

Other signs like severe epigastric pain or tenderness at McBurney's point may indicate other abdominal conditions such as pancreatitis or appendicitis, respectively, but they are not specific to cholecystitis. Additionally, the mention of bowel sounds may pertain to different gastrointestinal disturbances rather than indicating cholecystitis. Therefore, a positive Murphy's sign is a crucial and direct indicator of the diagnosis in this case.