Published online Oct 6, 2020. doi: 10.12998/wjcc.v8.i19.4499
Peer-review started: June 30, 2020
First decision: July 24, 2020
Revised: August 4, 2020
Accepted: August 26, 2020
Article in press: August 26, 2020
Published online: October 6, 2020
Processing time: 88 Days and 21.2 Hours
In most cases, it is not difficult to differentiate common bile duct (CBD) stone from Ascaris infection because they are different disease entities and have different imaging findings. The two diseases usually demonstrate unique characteristic findings on computed tomography or magnetic resonance cholangiopancreatography. However, we report a rare case from our experience in which a CBD stone mimicked and was misdiagnosed as Ascaris.
A 72-year-old male presented with elevated serum liver enzymes. Computed tomography showed a hyper-attenuated, elongated lesion in the CBD lumen and associated biliary inflammation. Magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography revealed a linear filling defect in the bile duct. Moreover, elongated echogenic material with a central hypoechogenic area was seen on endoscopic ultrasound. Although the imaging findings caused us to suspect infection with the nematode Ascaris, the lesion was revealed to be a dark-brown-colored CBD stone through endoscopic extraction.
We report a rare case of a CBD stone that mimicked Ascaris. We also review the literature for side-by-side comparisons of the imaging features of CBD stones and ascariasis.
Core Tip: Although common bile duct stone and Ascaris are not commonly discussed as differential diagnosis each other, they can be misunderstood in case of the elongated common bile duct stone. We should be able to learn the differential points through this case.