Acute or chronic inflammation of gallbladder. Murphy sign: inspiratory arrest on RUQ palpation due to pain. Pain may radiate to right shoulder (due to irritation of phrenic nerve).ALP if bile duct becomes involved (eg, ascending cholangitis).
FA 2019 page 390. This patient is expressing symptoms of biliary colic due to neurohormonal activation by CCK after a fatty meal. The labs will be normal and ultrasound will show cholelithiasis. However, I think this can be confused with acalculous because it also presents with inspiratory arrest on RUQ palpation due to pain. Acalculous cholecystitis is seen in critically ill patients.