Cysto-duodenal fistula: an unusual complication of a nonparasitic hepatic cyst.

Increasing use of radiological imaging modalities has resulted in the detection of nonparasitic hepatic cysts in 1%–5% of the general population, however, complicated nonparasitic hepatic cysts are exceedingly rare [1–4]. Here, we present a unique case of a hepatic cysto-duodenal fistula with the intracystic endoscopic findings. A 70-year-old man was admitted for postprandial abdominal discomfort and anemia of recent onset. Eight months previously, a 9×12-cm asymptomatic hepatic cyst in segments IV and V, which was compressing the duodenum, had been incidentally identified on computed tomography (CT) (●" Fig.1). On admission, simple abdominal radiography showed welldelineated, intra-abdominal gas with an internal air–fluid level in the right upper quadrant of the abdomen, but no intraabdominal free air (●" Fig.2). Laboratory studies revealed anemia (hemoglobin 7.5g/dL, hematocrit 23.7%, and serum ferritin 286.1ng/mL) compatible with acute blood loss. Esophagogastroduodenoscopy, using a conventional gastroscope, showed a 10mm penetrated peptic ulcer at the anterior wall of the duodenal bulb (●" Fig.3). An ultrathin endoscope (GIFXP260N, Olympus Optical Co., Tokyo, Japan), passed through the opening, revealed a huge unilocular cystic cavity with thick feeding vessels and foodmaterials in the cyst wall (●" Fig.4). However, there was no evidence of intracystic hemorrhageor abscess formation. Abdominal CT verified internal communication between the pre-existing hepatic cyst and the duodenal bulb through a fistulous Fig.2 Simple abdominal radiographic view showing a large amount of intra-abdominal air (asterisk) with an internal air–fluid level in the right upper quadrant of the abdomen. Fig.1 Contrastenhanced computed tomography in a 70-year-old man with postprandial abdominal discomfort and anemia of recent onset. There is a huge homogeneous cyst (asterisk) in segments IV and V of the liver, compressing the adjacent first portion of the duodenum (arrow). Fig.3 Endoscopic view showing a 10-mm penetrated peptic ulcer at the anterior wall of the duodenal bulb.