Alveolar Echinococcosis Mimicking Perihilar Cholangiocarcinoma Leading to Liver Transplant: A Case Report.

BACKGROUND Alveolar echinococcosis (AE) is a slowly progressive parasitic disease that primarily affects the liver and resembles primary or secondary liver neoplasms. Differentiating AE from other primary or secondary liver malignancies is of paramount importance, due to differing therapeutic approaches. The disease is uncommon in developed countries. Initial extrahepatic manifestation mimicking a primary biliary neoplasm is extremely rare. A broad differential diagnosis and low disease prevalence make the diagnosis of primary biliary AE extremely challenging. CASE REPORT We present a 32-year-old male patient with perihilar AE and no significant past medical history. The initial clinical presentation and radiological findings were compatible with the diagnosis of perihilar cholangiocarcinoma (Klatskin tumor). The patient subsequently underwent extensive invasive diagnostic procedures, including endoscopic ultrasound and endoscopic retrograde cholangiopancreatography, which led to choledochal perforation and biliary leakage, necessitating urgent surgical procedure, along with exploration, evacuation of enlarged lymph nodes, and subsequent histopathological examination. None of the procedures provided definitive evidence of malignancy. Only an ultrasound-guided percutaneous biopsy followed by histopathological examination revealed AE. Albendazole treatment and close follow-up were initiated. Subsequently, the patient experienced recurrent episodes of acute cholangitis. Recurrent cholangitis and perihilar biliary involvement, precluding radical surgical resection, necessitated liver transplantation. Ultimately, the patient underwent orthotopic liver transplantation from a brain-dead donor, with a favorable outcome. CONCLUSIONS Liver transplantation is a definitive treatment option for selected patients with perihilar liver involvement precluding radical resection of parasitic mass and recurrent episodes of acute cholangitis.