Suppurative parotitis
Acute suppurative parotitis is a bacterial infection of the parotid gland, most commonly caused by Staphylococcus aureus in a dehydrated or postoperative patient with reduced salivary flow, presenting with unilateral gland swelling and purulent ductal discharge, and treated with hydration, sialagogues, empiric antibiotics, and drainage of any abscess.
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What this article covers
- Overview
A bacterial infection of the parotid gland, almost always unilateral, arising when reduced salivary flow lets ascending oral flora colonize the gland: acute suppurative sialadenitis most commonly…
- Epidemiology
Occurs predominantly in dehydrated, postoperative, or hospitalized patients: conditions that decrease salivary flow, including volume depletion and the postoperative state, are the principal predisposing risk.
- Risk factors
Volume depletion (dehydration): reduced salivary flow from hypovolemia is the most consistently cited predisposing condition, particularly in hospitalized or postoperative patients with inadequate oral fluids.
- Pathophysiology
Reduced salivary flow removes the normal mechanical flushing that clears the ductal system of oral bacteria: when flow drops from dehydration, obstruction, or anticholinergic effect, bacteria are retained and can ascend.
- Clinical features
Acute, unilateral, painful swelling of the parotid gland: sudden-onset pain and swelling is the presenting feature, typically unifocal, distinguishing it from the bilateral, multifocal swelling of viral (mumps) parotitis.
- Differential diagnosis
Sialolithiasis (most common unifocal-swelling mimic): intermittent, postprandial pain and swelling from a duct stone, most often in the submandibular gland; distinguished by a palpable stone and…
- Diagnosis
The diagnosis is clinical, made on acute unifocal gland pain and swelling with purulent secretions expressible from the Stensen duct, and confirmed by imaging showing suppuration and by culture of…
- Management
First, correct the predisposing reduced salivary flow with hydration, sialagogues, warm compresses, and gland massage toward the duct orifice, using intravenous or oral fluids to reverse volume…
- Complications
Parotid abscess formation: untreated or inadequately treated suppuration can coalesce into a drainable abscess requiring surgical or image-guided intervention.
- Prognosis
Most cases resolve fully with prompt hydration, sialagogue measures, and appropriate antibiotics: early recognition and treatment of uncomplicated suppurative parotitis, without abscess formation, typically leads to complete resolution.
- Prevention
Maintain adequate hydration in hospitalized and postoperative patients, particularly those who are NPO or have limited oral intake for more than 24 hours: proactive fluid management directly addresses the leading predisposing risk factor.
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