What would indicate an abnormal result in a HIDA scan?

An abnormal result in a HIDA (Hepatobiliary Iminodiacetic Acid) scan is indicated by the absence of uptake in the gallbladder. Normally, the scan involves injecting a radioactive tracer, which is taken up by the liver and excreted into the bile. In a healthy individual, the gallbladder should show significant uptake of the tracer as it collects bile. If there is no uptake in the gallbladder, it suggests a dysfunction, such as acute cholecystitis or the absence of the gallbladder itself (cholecystectomy).

While increased uptake in the gallbladder or excessive uptake in the liver can be part of normal variations or other conditions, the key indicator of an abnormal scan is the lack of activity in the gallbladder. Delayed excretion into the bile may indicate other issues but does not directly indicate a gallbladder dysfunction as clearly as the lack of uptake would.