ENT · Salivary Gland Disorders

Sialadenitis

USMLE2PANCE
7

Bets

The facts most likely to be tested

1

Staphylococcus aureus is the most common bacterial pathogen causing acute suppurative sialadenitis.

Confidence:
2

Sialolithiasis (salivary stones) is the most common cause of sialadenitis, most frequently involving Wharton's duct (submandibular gland).

Confidence:
3

Patients with acute bacterial sialadenitis present with unilateral parotid or submandibular swelling, tenderness, and purulent discharge from the ductal orifice.

Confidence:
4

Dehydration, malnutrition, and postoperative status are the classic predisposing risk factors for acute parotitis.

Confidence:
5

Sialadenitis is diagnosed clinically, but ultrasound or CT scan is indicated if an abscess is suspected or symptoms fail to improve with initial therapy.

Confidence:
6

Initial management of acute sialadenitis includes hydration, warm compresses, sialagogues (e.g., lemon drops), and antistaphylococcal antibiotics.

Confidence:
7

Chronic recurrent sialadenitis is often associated with Sjögren syndrome or ductal strictures and may require sialendoscopy or surgical intervention.

Confidence:

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A 72-year-old male is brought to the clinic by his daughter due to 2 days of worsening right-sided facial pain and swelling. He recently underwent elective hip replacement surgery 5 days ago and has been on strict bed rest. On physical exam, he has erythema and tenderness over the right preauricular area. Gentle pressure on the right cheek results in the expression of purulent material from the Stensen duct. He is febrile to 101.2°F (38.4°C).

What is the most appropriate initial management for this patient?

+Reveal answer

Antistaphylococcal antibiotics and hydration

The patient presents with classic signs of acute suppurative sialadenitis (parotitis) secondary to dehydration and postoperative status, which is most commonly caused by S. aureus.

Mo

Depth

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High yield triage

Etiology / Epidemiology

Bacterial infection (usually Staphylococcus aureus) secondary to sialolithiasis or ductal obstruction.

Clinical Manifestations

Acute unilateral parotid/submandibular swelling with pus expressed from the duct.

Diagnosis

CT scan with contrast is the gold standard to evaluate for abscess formation.

Treatment

Dicloxacillin or Clindamycin; avoid anticholinergics that decrease salivary flow.

Prognosis

Most resolve with antibiotics; abscess formation requires surgical drainage.

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Epidemiology & Etiology

Common in the elderly, chronically ill, or dehydrated patients with xerostomia. Most cases are caused by retrograde bacterial migration from the oral cavity, frequently involving Staphylococcus aureus. Obstruction by sialolithiasis (salivary stones) is the most common predisposing factor.

Pertinent Anatomy

The parotid gland (Stensen's duct) and submandibular gland (Wharton's duct) are the primary sites of infection. Anatomy dictates that submandibular stones are more common due to the long, upward course of the duct.

Pathophysiology

Stasis of saliva leads to retrograde bacterial seeding of the gland. This triggers an inflammatory response, resulting in glandular swelling, pain, and potential micro-abscess formation. If untreated, the infection can progress to a deep neck space infection, a life-threatening complication.

Clinical Manifestations

Patients present with acute, tender, unilateral swelling of the affected gland. A pathognomonic finding is the expression of purulent discharge from the ductal orifice upon palpation. Red flags include trismus, dysphagia, or airway compromise, suggesting a deep neck abscess.

Diagnosis

Clinical diagnosis is often sufficient, but CT scan with contrast is the gold standard to differentiate simple sialadenitis from a deep space abscess. Ultrasound is a useful, radiation-free alternative for identifying sialolithiasis.

Treatment

Initial management includes Dicloxacillin or Clindamycin to cover staphylococcal species. Contraindications include medications that reduce salivary flow, such as antihistamines or anticholinergics. Hydration, warm compresses, and sialagogues (e.g., lemon drops) are used to stimulate salivary flow.

Prognosis

Most patients respond to conservative therapy within 48-72 hours. Failure to improve necessitates imaging to rule out a periglandular abscess, which requires surgical incision and drainage.

Differential Diagnosis

Sialolithiasis: intermittent pain/swelling related to meals without purulence

Mumps: bilateral parotitis, usually in unvaccinated children

Sjogren syndrome: chronic, bilateral, autoimmune-mediated xerostomia

Parotid tumor: firm, painless, slow-growing mass

Ludwig angina: bilateral submandibular space infection, usually odontogenic