Parotid Abscess

Parotid abscess is a collection of pus within the parotid gland, complicating acute suppurative parotitis. Staphylococcus aureus is the main organism, with streptococci and anaerobes.

• It affects dehydrated, elderly, malnourished, post operative and immunosuppressed patients, and neonates.
• Gland capsule and fascia hide fluctuance, so diagnosis can be delayed.
• It can spread to the parapharyngeal space and the neck.

Painful swelling in the cheek and in front of the ear, high fever, redness, trismus, pus from the Stensen duct opposite the second upper molar, and ear lobe elevation.

• Fluctuance is often absent even with abscess.
• Differential diagnosis: mumps, acute suppurative parotitis, parotid stone, pre auricular lymphadenitis, dental abscess, parotid tumour, lymphoma, tuberculosis, HIV related cystic disease, Sjogren syndrome.
• Complications: facial nerve palsy, parapharyngeal and retropharyngeal spread, airway compromise, osteomyelitis of the mandible, jugular vein thrombosis, sepsis, fistula.

Ultrasound and CT confirm the abscess.

• Ultrasound shows a hypoechoic collection; contrast CT for deep spread.
• Pus culture and blood cultures; full blood count, CRP, glucose, urea and electrolytes.
• HIV test; consider AFB and GeneXpert on aspirate if tuberculosis is possible.

Combine antibiotics with drainage and hydration.

• Supportive: IV fluids, oral hygiene, warm compresses, gland massage once settling, analgesia, stop drying drugs.
• Pharmacological: flucloxacillin 1 to 2 g IV every 6 hours with metronidazole 500 mg IV every 8 hours; or amoxicillin clavulanate 1.2 g IV every 8 hours; vancomycin 15 to 20 mg/kg IV every 8 to 12 hours when MRSA is likely; clindamycin 600 mg IV every 8 hours in penicillin allergy. Total 10 to 14 days, changing to oral amoxicillin clavulanate 625 mg three times daily when improved. Paracetamol 1 g every 6 hours.
• Procedures: ultrasound guided aspiration or incision and drainage under general anaesthesia using a modified facelift incision (Blair) with multiple small blunt incisions parallel to the facial nerve branches.
• Special groups: neonates, IV flucloxacillin and gentamicin with surgical review; diabetes, insulin and strict glucose control; HIV, culture for mycobacteria; pregnancy, amoxicillin clavulanate.
• Red flags: facial weakness, airway swelling, trismus, spreading neck swelling, sepsis, no improvement within 48 hours.
• Follow-up: review at 1 week and at 6 weeks; ultrasound to exclude residual stone or mass.