A previously healthy 30 years old man, with no medical history, was admitted to the emergency room after a car accident: rollover by his car. The physical examination on his admission was as follows: hearts rate of 145 beats/minute, blood pressure of 80/30 mmHg, with no signs of external bleeding, medullar trauma or limb fracture, the respiratory rate was 25 cycles/min, and pulse oximetry 75% on ambient air, 85% on high concentration mask with ronchis on the right side. The Glasgow Coma Scale GCS was 10/15 (eyes opening response 2/4, verbal response 3/5, and motor response 4/5) with contracted pupils, and no localization signs. At this moment a decision to put the patient on mechanical ventilation was taking with inspiratory fraction of oxygen at 100%, tidal volume og 6 mL/kg and pression end expiratory pressure at 3mBar, with pulse oximetry at 93%. The complete blood count showed the following: hemoglobin 12 g/dl, platelets 350000/mL, prothrombin time 80%, fibrinogen 3.5 g/l, white blood cells 7500/mL, eosinphils 55%, normal renal function: creatinine 0.8 mg/dl, urea 0.30 g/L. After hemodynamic stabilization by fluid restitution with 500 mL of saline serum, and introduction of norepinephrine 1 mg/h, the full-body computerized tomography CT scan was performed, and it showed no internal bleeding, pneumothorax or medullar trauma, and showed on the thoracic level where it showed a well limited rounded formation of regular contours containing a hydro-aeric level related to a ruptured hydatid cyst (). After ruling out the possibility of a hemorrhagic, hypovolemic shock, the diagnosis of anaphylactic shock due to post-traumatic rupture of hydatid cyst was maintained, norepinephrine was switched with epinephrine with a dose of 2 mg/h, and we gave him 500 mg of hydrocortisone with improvement in the hemodynamic state. The patient was admitted to the operating room the next day for cyst removal by open thoracotomy (). In the postoperative period, Albendazole was started with a dose of 400 mg/day. The evolution was favorable; he was extubated in the immediate post-operative period and referred to the thoracic department.