Alveolar Echinococcosis - Diagnostic challenges of a parasitic disease on the rise in Europe - a case report.

A 45-year-old male presented with jaundice, abdominal discomfort, and weight loss. Abdominal ultrasound revealed intrahepatic cholestasis and cholelithiasis indicative of Caroli-syndrome. Subsequent magnetic resonance imaging demonstrated a corresponding 5 × 4 cm polycyclic, calcified mass and a distant 12 mm subhilar stenosis of the common bile duct resembling cholangiocarcinoma. Calcifications seemed unusual and brought up differential diagnosis of echinococcosis. Serology revealed an echinococcus antibody-titer of 33 U (cut-off > 11.5 U). However, the clinical presentation with jaundice, weight loss, and a distant subhilar stenosis of the common bile duct without association to the intrahepatic process led to underestimation of the positive antibody-titer. Thus, the patient underwent right hemihepatectomy for potential cholangiocarcinoma. Dense infiltrative small cysts interspersed the resected right lobe of the liver. Histopathology revealed a granulomatous inflammation surrounding typical cuticulas, confirming hepatobiliary alveolar echinococcosis. Alveolar echinococcosis is considered as one of the neglected diseases by the World Health Organization, although incidence is rising worldwide and specifically in Germany. Our case illustrates hurdles in diagnosing alveolar echinococcosis and underlines the importance to be aware of classical and rare clinical manifestations.