Unilateral Facial Swelling with Pus: Causes from Dental to Deep Space Infections

One-sided facial swelling with pus indicates localized infection requiring prompt source identification.

Top Etiologies

1. Odontogenic: Periapical abscess → cellulitis → submandibular/buccal/ludwig's angina (bilateral submandibular – airway emergency).
2. Cutaneous: Cellulitis, abscess (furuncle/carbuncle) from S. aureus, Strep.
3. Salivary Gland: Parotitis (Staph, viral – mumps), submandibular sialadenitis (stone/stasis).
4. Sinusogenic: Acute sinusitis → orbital/periorbital cellulitis (medial canthus swelling).
5. Periorbital/Orbital: Preseptal vs. postseptal (ophthalmoplegia, proptosis, vision loss = emergency).
6. Lymphadenitis: Suppurative node (cat scratch, TB, bacterial).
7. Trauma: Infected hematoma/laceration.

Urgent Evaluation For

• Difficulty breathing/swallowing (Ludwig's, deep neck space)
• Vision changes, ophthalmoplegia (orbital)
• Systemic toxicity (sepsis)
• Rapid progression

CT with contrast defines extent. IV antibiotics ± surgical drainage.