Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 21 3 2026 09 02 420 425 Thanh Ho Military Hospital 103, Vietnam Military Medical University, Hanoi, Vietnam Chuyen Nguyen Department of Military Hygiene, Vietnam Military Medical University, Hanoi, Vietnam Hai Do Military Hospital 103, Vietnam Military Medical University, Hanoi, Vietnam Trang Nguyen Department of Military Hygiene; Vietnam Military Medical University, Hanoi, Vietnam. Anh Le Department of Military Hygiene, Vietnam Military Medical University, Hanoi, Vietnam Tuan Vu Department of Military Hygiene, Vietnam Military Medical University, Hanoi, Vietnam Truong Hoang Department of Military Hygiene, Vietnam Military Medical University, Hanoi, Vietnam Huong Pham Military Hospital 103, Vietnam Military Medical University, Hanoi, Vietnam Cuong Le Vietnam University of Traditional Medicine, Hanoi, Vietnam 2025 12 16 2026 09 02 Larval forms of Echinococcus tapeworm infection (Cystic Echinococcosis - CE) are a zoonosis of major public health relevance. While prevalent in many Asian countries, it is rarely reported in Vietnam. We present a case of a 73-year-old male farmer from rural Bac Ninh Province with a history of close contact with dogs and consumption of raw vegetables. Originally diagnosed with an asymptomatic 40-mm simple hepatic cyst in 2020, he presented in 2025 with high fever and subcostal pain. Imaging (US/CT) and ELISA serology confirmed a suppurated Echinococcus sp. cyst (WHO stage CE3a). Notably, laboratory results showed a significant systemic inflammatory response with unusual lymphocytosis. The patient underwent a successful partial left hepatectomy and received adjuvant albendazole therapy. This case underscores the necessity of considering CE in the differential diagnosis of hepatic cysts in non-endemic regions like Vietnam, especially when complicated by abscess formation. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/4849 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/4849/1518