Functional gallbladder disorder is characterized by presence of biliary pain and absence of gallstones or other structural pathology. According to Rome IV criteria, biliary pain is defined as pain in the epigastrium and/or right upper quadrant that builds up to a steady level and lasts at least 30 minutes, occurs at different intervals (usually not daily), is severe enough to interrupt daily activities or lead to an emergency department visit, and is not significantly related to bowel movements or relieved by postural change, or acid suppression. Criteria that are supportive of biliary pain, but are not required, include pain that is associated with nausea and vomiting, radiation of pain to the back and/or right infrascapular region, and pain that awakens the patient from sleep.
HIDA scan with CCK is used to estimate the gallbladder ejection fraction to support the diagnosis of functional gallbladder disorder and to select patients who may benefit from cholecystectomy. A gallbladder ejection fraction of less than 35-40% is considered low. Low ejection fraction on scintigraphy is supportive but not diagnostic of functional gallbladder disorder. False-positive results can be seen with diabetes, celiac disease, obesity, cirrhosis, and medications.
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