Differential Diagnoses for Acute Cholecystitis

Primary Biliary Differentials

The American College of Radiology suggests that chronic cholecystitis presents with recurrent right upper quadrant pain but typically lacks fever and leukocytosis that characterize acute cholecystitis 1
The American College of Radiology recommends that the diagnosis of chronic cholecystitis is difficult on anatomic imaging alone; clinical context and chronicity of symptoms are key distinguishing features 2
The American College of Radiology states that ascending cholangitis is distinguished from acute cholecystitis by the presence of jaundice indicating biliary obstruction 3

The American College of Radiology notes that peptic ulcer disease can present with epigastric or right upper quadrant pain and typically lacks fever and leukocytosis unless complicated by perforation 1
The American College of Radiology recommends that ultrasound can help exclude biliary pathology while identifying alternative diagnoses such as peptic ulcer disease 2
The American College of Radiology states that acute pancreatitis presents with epigastric pain that may radiate to the right upper quadrant and that ultrasound evaluation should assess the pancreas and identify gallstones as a potential etiology 2
The American College of Radiology suggests that CT with IV contrast may be needed to evaluate for pancreatic complications in acute pancreatitis 4

The American College of Radiology recommends that ultrasound can assess for cirrhosis with sensitivity of 65-95% and positive predictive value of 98% 5

The American College of Radiology recommends starting with right upper quadrant ultrasound as the initial imaging modality, which has 96% accuracy for detecting gallstones and can identify alternative diagnoses 2, 6
The American College of Radiology suggests that if ultrasound confirms acute cholecystitis, proceed to surgical consultation 2
The American College of Radiology recommends that if ultrasound is negative or equivocal and clinical suspicion remains high, order hepatobiliary scintigraphy (HIDA scan), which has 97% sensitivity and 90% specificity for acute cholecystitis 2, 6
The American College of Radiology states that if ultrasound suggests biliary obstruction with dilated common bile duct, order MRCP to evaluate for choledocholithiasis or cholangitis, which has 85-100% sensitivity and 90% specificity 5
The American College of Radiology recommends that if ultrasound is negative and there is no alternative diagnosis, order CT with IV contrast to evaluate for complications or alternative pathology 4, 1