Concentrations of bile, including bile salts, phospholipids, and even cholesterol, may be altered, thus inducing mucosal inflammation. Arterial occlusion and ischemia may be late changes. Pain becomes severe, localizing to the right upper quadrant, often radiating to the right lower scapula. Nausea and vomiting are usual. Within a few hours, the primary physical finding is involuntary guarding of right-sided abdominal muscles, without rebound tenderness at first.
Fever is low grade at first, and neutrophilia is modest.
Failure to do so suggests serious complications. High fever, leukocytosis, and rigors with rebound tenderness or ileus suggest empyema, gangrene, or perforation, which require urgent surgical management. When acute cholecystitis is accompanied by jaundice or cholestasis, partial common duct obstruction may result from calculi or contiguous inflammation. Diagnosis Clinically suspected acute cholecystitis is most accurately confirmed by cholescintigraphy and ultrasound. Cholescintigraphy entails administering IV iminodiacetic acid compounds labeled with radioactive technetium 99m, which are rapidly taken up and excreted by the normal liver.