Hereditary angioedema (HAE) is a autosomal dominant disease, characterized by recurrent episodes of angioedema and caused by deficiency or functional alteration of the plasma protein C1 inhibitor (C1-INH), an enzyme involved in the regulation of the complement, contact, fibrinolytic, and coagulation systems. It prevalence is not known for sure, but has been estimated to range from 1:10,000–150,000 in the general population. HAE is characterized by episodes of edema of larynx, face, gastrointestinal tract, or extremities. Laryngeal edema, a life-threatening symptom, has been reported to occur predominantly after oral surgery. We describe a case of an 18 year-old, male, no-incident medical history, skeletal Class II with anterior open bite and mandibular retrognathia patient, who underwent orthognathic surgery. Immediate postoperative showed no problems. On the second day postoperative, the patient showed severe edema that threatened the airway. He was taken to operating room where an endotracheal intubation was performed. The patient was taken to the ICU where he was tested for C1-INH plasmatic concentration. The result of this test showed a below normal concentration of plasma protein C1 inhibitor (C1-INH), hence, the diagnosis was HAE. The patient was then given fresh frozen plasma and a few hours later there was an improvement of his general condition.

Several cases of HAE that underwent oral surgery have been reported, but to our knowledge this is the first case reported of a patient undergoing orthognathic surgery. This case’s treatment will be described, and a review of the pathology and management literature available will be made.

Conflict of interest: None declared.