Radiolucent gallstones
Presentation
Sudden onset of right upper quadrant pain and jaundice. Rule out of gallstones or pancreatic tumor.
Patient Data
CT abdomen
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Biliary duct dilatation up to distal part of common bile duct with no visible stones. The pancreas is unremarkable without signs of tumor or ectasia of the duct of Wirsung.
A hepatic cyst is noted at each lobe, larger on the right lobe.
Left renal angiomyolipoma noted (contains macroscopic fat).
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Bile duct dilatation withous visible problem.
So, CT shows no gallstones disease or pancreatic head tumor. We decided to perform endoscopic retrograde cholangiopancreatography (ERCPG).
ERCP
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ERCP shows a lot of gallstones within the common bile duct.
Case Discussion
Acute right upper quadrant pain and fever are very suspicious for choledocholithiasis. But always remember about radiolucent gallstone which isodense to bile and may not be identified on X-ray or CT as in this case.
So, if you don't see gallstones on CT you should use other options such as US, MRI or ERCP which are more sensitive for radiolucent calculi.