Rapidly enlarging, giant hepatic cyst growing pseudomonas.

A 74-year-old woman presented with dyspnoea and fever on a background of a large hepatic cyst thought to be stable in size. During her admission, she developed worsening shortness of breath. An echocardiogram revealed severely impaired cardiac output due to external compression by the hepatic cyst, which had grown rapidly. This was drained under ultrasound guidance and cultures of this fluid grew Pseudomonas aeruginosa: the organism responsible for the persistence of this giant hepatic cyst.