Successful surgical drainage with intraoperative ultrasonography for amebic liver abscess refractory to metronidazole and percutaneous drainage: a case report.

Background: Metronidazole (MNZ) has been clearly established as a medication for amebic liver abscess. In uncomplicated cases, surgical drainage should be avoided. We report a case of amebic liver abscess refractory to MNZ that was successfully treated using preoperative computed tomography (CT) and percutaneous and surgical drainage with intraoperative ultrasonography (IOUS).
Case Presentation: A 53-year-old man with high-grade fever was diagnosed with a cystic lesion on his right hepatic lobe using CT. Percutaneous drainage was performed, and antibacterial drugs were administered. However, the infection and condition of the patient worsened. Entamoeba histolytica was detected from pus within the mediastinal cavity. Hence, the patient was diagnosed with amebic liver abscess. After the diagnosis was established, we administered MNZ for 10 days. Despite this, the patient's physical condition did not improve. Blood tests suggested impending disseminated intravascular coagulation (DIC). We performed surgical intervention to drain the amebic liver abscess refractory to conservative treatment. During surgery, imaging information from preoperative CT and IOUS enabled us to recognize the anatomical structures and determine the incision lines of the hepatic capsule and hepatic tissue. The patient's DIC immediately regressed after surgery. Unfortunately, malnutrition and disuse syndrome contributed to the patient's long recovery period. He was discharged 137 days post-surgery.
Conclusions: We reported a case of amebic liver abscess refractory to conservative treatment. Surgical drainage with preoperative CT and IOUS allowed us to safely and effectively perform complex abscess decompression.