A Case of Giant Hepatic Hydatid Cyst Infected with Morganella morganii and the Literature Review.

Hydatid cyst disease is a common worldwide zoonosis. Most of the cysts are located in the liver. Abscess formation due to infection of the cyst is an important complication. M. morganii, a Gram-negative Bacillus, is a quite rare cause of liver abscess. A 77-year-old woman was admitted to hospital with complaints of fever, chills, nausea, vomiting, loss of appetite, and abdominal pain located in the right-upper quadrant. Her history was positive for hepatic hydatid cyst disease ten years ago. Physical examination revealed a painful mass filling the right-upper quadrant and extending down to umbilicus. Indirect hemagglutinin test for hydatid cyst was positive at a titer of 1/320. Giant liver abscess due to infected hydatid cyst was found in computed tomography scan. Surgeons performed cystectomy and cholecystectomy. Cefazoline, cefuroxime, and metronidazole were administered empirically, but all the three agents were replaced with intravenous ceftriaxone after M. morganii was isolated from the cultures of the abscess material. Clinical signs of the patient resolved at the second week of treatment, and she was discharged.