Acute Bacterial Parotitis with Purulent Stensen Duct Drainage
When pus is present in Stensen's duct with parotitis, the cause is bacterial—specifically Staphylococcus aureus—not mumps, and requires immediate antibiotic therapy targeting this pathogen. 1, 2
Key Diagnostic Distinction
The presence of purulent discharge from Stensen's duct is pathognomonic for acute bacterial suppurative parotitis, not viral mumps. 3, 4 This clinical finding definitively distinguishes bacterial from viral etiology:
- Bacterial parotitis: Purulent discharge expressible from Stensen's duct, often with local erythema, warmth, and tenderness 1, 3
- Viral mumps: No purulent discharge; diagnosis requires viral PCR from parotid duct swabs or mumps IgM serology 5, 6
Microbiology of Bacterial Parotitis
The most common pathogen is Staphylococcus aureus, accounting for the majority of acute bacterial suppurative parotitis cases. 1, 2, 3, 4
Other pathogens include:
- Anaerobic bacteria (Prevotella, Porphyromonas, Fusobacterium, Peptostreptococcus) 1
- Streptococcus viridans 3
- Gram-negative bacilli (E. coli, Klebsiella, Pseudomonas) particularly in hospitalized patients 1, 2
Immediate Management Algorithm
1. Obtain Culture Before Antibiotics
- Massage the parotid gland for 30 seconds and swab purulent discharge from Stensen's duct for Gram stain and culture 5, 3
- This guides definitive antibiotic therapy based on sensitivities 1, 2
2. Start Empiric Antibiotic Therapy Immediately
Initiate parenteral antibiotics targeting S. aureus and anaerobes while awaiting culture results. 1, 2
Appropriate empiric regimens include:
- Anti-staphylococcal penicillin (nafcillin/oxacillin) PLUS metronidazole for anaerobic coverage 1
- Vancomycin if MRSA risk factors present (healthcare exposure, prior MRSA, local prevalence) 1, 2
- Consider adding gram-negative coverage (ceftriaxone or fluoroquinolone) in hospitalized or immunocompromised patients 1
3. Supportive Measures
- Aggressive hydration (IV fluids if needed) to promote salivary flow 1, 2
- Sialagogues (lemon drops, sour candies) to stimulate saliva production 1
- Warm compresses and massage of the gland 2
- Maintain oral hygiene 1
4. Surgical Drainage if Abscess Forms
If fluctuance develops or patient fails to improve within 48-72 hours on antibiotics, surgical drainage is required. 1, 2 Imaging (ultrasound or CT) can identify abscess formation requiring intervention. 2
Critical Pitfall to Avoid
Do not assume viral etiology (mumps) when purulent discharge is present. The presence of pus from Stensen's duct mandates treatment for bacterial infection, not supportive care alone. 1, 3, 4 Conversely, confirmed viral mumps should never receive antibiotics, as this contributes to antimicrobial resistance without benefit. 6
When to Consider Mumps
Mumps should only be considered when: