The patient is a 9-year-old boy, a student from Ziyun County, Anshun City, Guizhou Province. He has experienced constant pain and discomfort in his upper right abdomen since August 2021. He was admitted to the 302 Hospital of the China Guihang Group on September 10, 2022 with a "liver occupying lesion: suspected liver abscess with calcification or tumor". The epidemiological investigation indicated that the boy has no history of travelling to epidemic areas. His parents have been engaged in livestock (dogs) slaughter for a long time, and some dogs were purchased from Echinococcosis epidemic areas such as Tibet Autonomous Region and Sichuan Province. The patient often came into contact with those dogs. The admission examination showed no yellowing of the skin and sclera throughout the body, slight tenderness in the right upper abdomen, and no palpable liver mass. Blood cell count showed that the percentage of eosinophils was 20.1%. The liver function testing results were showed γ Glutamic transferase was 36 U/L. The enhanced CT scan of the upper abdomen showed a patchy mixed-density shadow in the right posterior lobe of the liver, which is lobulated. Multiple patchy and tortuous earthworm-like high-density calcification shadows distributed in clusters. Multiple grid-like septal shadows were observed in the enhanced scan at the lesion, with mild continuous enhancement at the edges and septal areas. The abdominal color ultrasound showed an elliptical-shaped, uneven, strong echogenic mass in the right posterior lobe of the liver. Laparoscopic resection of the right posterior lobe of the liver was performed on September 14th, and compensatory enlargement of the right posterior lobe was observed. A milky white mass was seen in segments Ⅵ and Ⅶ, approximately 6 cm × 7 cm × 5 cm, with uneven surface and hard texture. The postoperative pathological section results showed inflammatory necrosis of the liver tissue. Postoperative blood cell count showed a normal of eosinophil percentage. Postoperative CT reexamination of the upper abdomen revealed postoperative changes, and no other obvious abnormalities were found. Therefore, the child was discharged. On November 10th, the patient went to the Affiliated Hospital of Guizhou Medical University for review, and the serum test indicated that Echinococcus antibody was positive. The cytochrome c oxidase subunit 1 (cox1) and nicotinamide adenine dinucleotide dehydrogenase subunit 1 (nad1) gene fragments of Echinococcus were amplified by PCR from the lesion tissue DNA by National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research) on November 29th. The amplified cox1 and nad1 gene fragments have high sequence similarity of 99.42% and 99.59% with the cox1 gene (reference sequence registration number AB477010) and nad1 gene (reference sequence registration number AJ132907) of E. multilocularis, respectively. The diagnosis of echinococcosis multilocularis was confirmed. The patient was administered with 15 mg/(kg·d) orally albendazole, which was taken separately after breakfast and dinner for a course of 6 months and followed-up the patient regularly.