A patient had a biopsy taken in the area of tooth #13. The next morning the upper lip is markedly swollen but the SAME COLOUR as the surrounding mucosa, and the swelling is soft and non-tender. What is the most likely diagnosis?

Correct answer: B. Angioedema

• A. A HAEMATOMA from needle trauma or the surgical site would appear BLUE, PURPLE or BLACK as extravasated blood breaks down, and would usually be firmer and tender. The stem specifically states the mucosa is normal in colour.
• B. CORRECT. ANGIOEDEMA is a rapid-onset, non-pitting swelling of the deep dermis and submucosa produced by increased vascular permeability, and the key clinical clue in the stem is that the overlying tissue is NORMAL IN COLOUR — there is oedema fluid, not extravasated blood. It is typically soft, non-tender and non-pruritic. Common precipitants after a dental visit are LATEX, chlorhexidine, local anaesthetic components (particularly the preservative), and analgesics; ACE INHIBITORS are a frequent drug cause that can present at any time. Management ranges from antihistamines and corticosteroids for mild cases to epinephrine and airway protection if the tongue, floor of mouth, or larynx is involved.
• C. A mucocele arises days to weeks after a minor gland duct is severed, is a discrete DOME-SHAPED fluctuant nodule rather than diffuse lip swelling, is usually bluish, and is overwhelmingly a LOWER lip lesion.
• D. A haemangioma is a congenital or early-life vascular lesion that is BLUE-RED and BLANCHES on pressure. It does not appear overnight after a biopsy.

Note: Airway is the priority in any facial angioedema. Ask about ACE inhibitors and about a family history of recurrent swelling — HEREDITARY angioedema (C1 esterase inhibitor deficiency) does NOT respond to epinephrine, antihistamines or steroids and needs C1-INH concentrate or icatibant.