Lung metastasis caused by an infection with Echinococcus alveolaris.

Echinococcus alveolaris (E. alveolaris) (multi-localaris) is a parasitic agent that commonly affects the liver and poses as a solid mass. In contrast to Echnicoccus granulosus, E. alveolaris tends to invade adjacent structures rather than displace and compress them. Haematogenous dissemination to other organs such as the lungs, brain, or bone is rare. In this case, we report on a 34-year old woman with a history of liver segmentectomy due to E. alveolaris infestation and the disease disseminated to the lungs. Computed tomography and magnetic resonance imaging showed multiple opacities and mixed signal intensities in the lungs, mimicking metastatic disease. The biopsy proved that the lesions were a result of metastasis of E. alveolaris.