Anaphylactic shock is an exceptional mode of revelation of a liver hydatid cyst and it is in almost all cases secondary to an intraperitoneal rupture. The spread of hydatid cyst content into the bloodstream is even more exceptional. We report the case of a 36 years-an old woman who presented a severe anaphylactic shock preceded by abdominal pain. Abdominal CT showed a liver hydatid cyst with a vascular communication. Operative findings confirmed the imaging data. The spread of hydatid cyst content into the bloodstream poses a double challenge as regards the management of the anaphylactic shock, and for the perioperative precautions.