CT	Image 60: This 36 year emigrated from Syria to Canada in 2000. He described a right lower lung hydatid removal in 1991 after he coughed up "much stuff" and an anaphylaxis in 1997. He presented in 2007 with a story of a recent emergency room admission for anaphylaxis. He had been followed for 7 years elsewhere for an unchanging right hilar cyst.  Six weeks after the recent anaphylaxis his CBC was normal (no eosinophilia) and his echinococcal serology was highly positive (ELISA OD 1.18 [normal <0.35]). He had no pulmonary symptoms. The images here strongly suggest an hydatid in the right pulmonary artery. How would you treat it? See our approach.
CT	gated MRI

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Image 60: Hydatids have been found in every organ of the body, each associated with location-specific management challenges.The rarity of pulmonary artery hydatids means there may be no right answer. In this case the artery presumably was seeded at the time of the lung hydatid surgery. This hydatid appears to extend into the right middle and lower lobe arteries like fingers in a glove.A VQ scan showed a lack of perfusion of the entire right lower lobe and of the right middle lobe associated with a normal ventilation scan.

We have elected to treat him with long term (2 years?) albendizole with intermittant radiological assessments. He will carry injectable epinephrine (EpiPen). We are open to advice. 

Dursun M et al. Cardiac hydatid disease: CT and MRI findings. AJR 190; 226-232: 2008