Pathophysiology involves dehydration or decreased oral intake leading to salivary stasis and subsequent bacterial migration into the gland. Medically debilitated and postoperative patients are therefore at greater risk; so are patients with diabetes mellitus, poor oral hygiene, Sjögren’s syndrome, hypothyroidism, or renal failure.16 Certain medications, including anticholinergics, can also predispose to hyposalivation.17
(As discussed, sialolithiasis and stricture of salivary ducts can also cause acute bacterial infection; in such cases, however, the typical presentation is one of chronic or recurrent infection.)
Examination might reveal an exquisitely tender, indurated, and inflamed gland; pus can often be expressed from the respective intraoral orifice. Any expressed pus should be sent for culture to guide antibiotic therapy.
Treatment should focus on hydration, oral hygiene, and antibiotics, while reversing or minimizing any underlying contributing medical condition. Warm compresses applied to the involved gland, massage, and sialagogues, such as lemon drops or sugar-free lollipops, can stimulate salivary flow and prevent stasis.
More than 80% of infections are caused by Staphylococcus aureus17; anaerobic and mixed infections have also been recognized.A beta-lactam penicillin, such as amoxicillin-clavulanate, is the antibiotic of choice. A patient who is systemically unwell should be treated as an inpatient with nafcillin and metronidazole. Methicillin-resistant S aureus must also be considered in patients with comorbid disease, such as diabetes mellitus or intravenous drug use, or in patients residing in an area of substantial incidence of methicillin-resistant S aureus. In those cases, substitute vancomycin or linezolid for nafcillin.18
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