A pyogenic liver abscess (PLA) mostly occurs in association with biliary tract disease, but some PLAs have no apparent underlying cause, i.e., they are cryptogenic. The authors experienced three cases of PLA or liver cyst infection after colon polypectomy without other distinct etiologies. These cases suggest that colonoscopic polypectomy can cause a mucosal defect that provides a route for bacteria to invade the portal system or spread intraperitoneally to the liver. Colonoscopic polypectomy should be considered as a procedure that might cause PLA. Moreover, clinicians should be aware of this possibility if a patient complains of fever or abdominal pain after a colonoscopic polypectomy.
Keywords: Colonoscopy; Liver abscess; pyogenic.