An unusual cause of recurrent facial oedema

A man in his early 20s presented to the otolaryngology emergency department with a 10 hour history of swelling affecting his face and left hand, with associated difficulty breathing. He had no associated rash or pruritus, and reported no clear precipitating factors. Physical examination revealed facial swelling (fig 1) and oedema of the tongue, soft palate, uvula, epiglottis, and vocal folds.

The patient had a two year history of recurrent swelling affecting the face and left hand. He had no family history of similar episodes. He had previously been identified as allergic to various food and inhalant allergens, but had never had anaphylactic reactions and did not report exposure to any of these allergens in the current presentation.

Despite lack of exposure to a known or probable allergen, the patient’s condition was managed as anaphylaxis because of the significant facial angioedema and dyspnoea, but with no significant improvement.

After acute management, further investigations of his complement pathway showed C1q 2 U/mL (normal range …