Introduction

Hydatid disease is a worldwide zoonosis produced by the larval stage of the echinococcus tapeworm. This disease primarily affects the liver and typically demonstrates characteristic imaging findings. However, it has many potential local complications including biliary complications and perforation into hollow viscera.

The classical findings in hydatid disease are well known; however, findings related to complications and unusual anatomic locations are less frequently described in the literature (₁). We present a case of hepatic hydatid disease presenting a cystogastric fistula as an extremely rare complication.

Case report

A 42-year-old woman was admitted to Al-Zahra Hospital in Isfahan in July 2008, complaining of abdominal pain, fever and jaundice. The patient had a history of dyspepsia, abdominal pain and jaundice intermittently from 6 months before admission with increased severity of pain and jaundice during 30 days before hospitalization. Past history was normal. On physical examination, the patient was febrile and icteric.

Abdominal ultrasonography showed a large cyst of the left liver lobe and dilatation of intrahepatic ducts and common bile duct. Upper endoscopy (done because of dyspepsia and epigastric pain) revealed an orifice in the greater curvature of the stomach at the junction of body and antrum. Abdominopelvic CT scan showed fistulous communication between hepatic hydatic cyst and stomach (figure1).

Midline laparatomy was performed and the following procedures were done:

a- Evacuation of the hydatid cyst of the left liver lobe

b- Biopsy of the stomach at the site of the orifice of the fistula and repair of the stomach in two layers

c- Cholecystectomy, exploration of CBD and removal of the laminated layer of the hydatid cyst from the CBD.

d- Choledochoduodonostomy

Pathologic examination confirmed a hydatid cyst fistula to the stomach (figure 2).

The patient was discharged after 5 days of hospitalization and had no problems in a 6-months follow-up period.

Conclusion

Spontaneous rupture of a hydatid cyst into hollow viscera is an extremely rare complication with an estimated frequency of 0.5% (₂). This complication may be accompanied by clinical findings of hydatidemesis or hydatidorrhea (₃). Typically, the fistulous communication is not discovered until surgery; although in some patients it is found at radiology (₃). CT scan may demonstrate a cyst with an air-fluid level or oral contrast material inside the cavity. Barium-enhanced CT can be used to demonstrate the fistula between the cyst and the hollow viscus. Furthermore, biliary communication of hydatid disease has been described in up to 90% of hepatic cysts (₂, ₄). However, frank rupture into the biliary tree occurs in only 5-15% of cases (₂).

Jaundice, fever and chills are the most frequent symptoms related to biliary obstruction and cholangitis (₅). CT is the modality of choice in depicting hydatid cyst contents in the CBD, although endoscopic retrograde cholangiography may provide an excellent diagnostic and therapeutic modality in surgically high-risk patients (₆).

Familiarity with theses atypical manifestations of hydatid disease may be helpful in making an accurate diagnosis and treatment.

Figure 1

Figure1: CT scan showing fistulous communication between hepatic hydatid cyst and stomach

Figure 2

Figure 2: Pathology revealing the laminated layer of the hydatid cyst

Correspondence to

Reza Eshraghi Samani Address: 27, 5^th floor, Shahrivar block, Moshtagh building, Jeyshir Street, Isfahan, Iran. Tel: +983112630716 E-Mail: eshraghireza@yahoo.com