A 62-year-old woman with obstructive jaundice was diagnosed with pancreatic head cancer. She developed fever after endoscopic placement of a biliary stent. We initiated treatment with sulbactam/cefoperazone for cholangitis; however, fever and elevation of inflammatory biomarkers persisted. We performed abdominal ultrasonography, which showed debris within a huge hepatic cyst (16 cm), and we diagnosed hepatic cyst infection. EUS-guided transgastric cyst drainage was performed. We punctured the cyst from the upper gastric corpus using a 19 G needle. We advanced a guide-wire into the cyst, dilated the puncture route using a 7F dilator, and inserted a 7F, 7-cm double-pigtail plastic stent. Following the procedure, the inflammatory response subsided with reduction in cyst size. She was discharged on day 9 after cyst drainage. No relapse of the hepatic cyst infection was observed.
