Salivary Gland Abscess

Salivary gland abscess is a pus collection within a major or minor salivary gland, usually after obstruction and ascending infection of the parotid, submandibular or sublingual gland. Staphylococcus aureus, streptococci and anaerobes are the main organisms.

• Submandibular and sublingual abscesses can spread to the floor of the mouth.
• Predisposing factors are stones, dehydration, poor oral hygiene, diabetes and immunosuppression.
• Minor gland abscesses follow trauma to the lip or palate.

Firm, tender, red swelling in the affected gland region, fever, malaise, bad taste, pain with eating, and pus from the duct.

• Floor of mouth swelling, tongue elevation, drooling and trismus point to a spreading space infection.
• Differential diagnosis: dental abscess, lymphadenitis, tumour, ranula, Ludwig angina, tuberculosis, mumps, sialolithiasis, infected branchial cleft cyst.
• Complications: airway obstruction, deep neck infection, mediastinitis, sepsis, fistula, chronic gland damage.

Ultrasound, CT and culture establish the diagnosis.

• Ultrasound shows a collection and any stone; contrast CT for deep or floor of mouth disease.
• Culture of pus; blood cultures if febrile; full blood count, CRP, glucose.
• HIV test and AFB stain on aspirate if chronic.

Drain the pus, give antibiotics and restore salivary flow.

• Supportive: IV fluids, nil by mouth if airway is threatened, oral hygiene, warm compresses, analgesia, head up position.
• Pharmacological: amoxicillin clavulanate 1.2 g IV every 8 hours, or ceftriaxone 2 g IV daily with metronidazole 500 mg IV every 8 hours; clindamycin 600 mg IV every 8 hours in penicillin allergy. Oral step down to amoxicillin clavulanate 625 mg three times daily to complete 10 to 14 days. Paracetamol 1 g every 6 hours.
• Procedures: ultrasound guided needle aspiration, or incision and drainage (intraoral for sublingual and minor gland abscess, extraoral submandibular incision for submandibular abscess); removal of stone and later gland excision for recurrent disease.
• Special groups: children, weight based IV antibiotics and early ENT review; pregnancy, amoxicillin clavulanate; immunosuppressed, culture, AFB and broad cover.
• Red flags: stridor, floor of mouth elevation, drooling, trismus, neck swelling, spreading cellulitis, persistent fever.
• Follow-up: review at 48 hours and 1 week; ultrasound after recovery for residual stone.