Well-defined, rounded hypodense cystic lesion in right lobe of liver. Multiple collapsed thin membranes are seen within it (yellow arrows).
Loculated collection in perihepatic region and involving the right abdominal wall. It is communicating with the above cystic lesion (white arrow).
Ruptured hepatic hydatid cyst
NONE! This is an Aunt Minnie.
Urgently inform the referring clinician and refer to surgical team on call.
Urgent surgical intervention is the mainstay of treatment – removal of cyst membrane and closure of tract.
Supplementary treatment with anti-helminthic drugs.
Hydatid disease is caused by the parasitic infection of Echinococcus.
Echinococcus is a tapeworm found in dogs (definitive host), pigs (intermediate host), sheep, goats and cattle. Humans are accidental hosts. Infection occurs by ingestion of food which is contaminated by Echinococcus eggs.
Liver is the most involved organ followed by lungs and spleen. Cerebral and spinal hydatid cysts have also been reported.
Cyst wall is made up of 3 layers, namely:
Calcified hydatid cysts can be seen as rounded opacities on radiographs.
PAIR procedure (Puncture, Aspiration, Injection and Re-aspiration) is usually performed for treatment of un-ruptured hydatid cyst.
Pedrosa, I., Saíz, A., Arrazola, J., Ferreirós, J., & Pedrosa, C. S. (2000). Hydatid Disease: Radiologic and Pathologic Features and Complications. RadioGraphics, 20(3), 795–817. doi:10.1148/radiographics.20.3.g00ma06795 (https://doi.org/10.1148/radiographics.20.3.g00ma06795)
Kantarci M, Bayraktutan U, Karabulut N et al. Alveolar Echinococcosis: Spectrum of Findings at Cross-Sectional Imaging. Radiographics. 2012;32(7):2053-70. doi:10.1148/rg.327125708 – Pubmed