What is the likely diagnosis and initial conservative treatment for a patient with unilateral submandibular gland swelling due to a suspected salivary stone (sialolithiasis)?

Submandibular Gland Swelling from Salivary Stone

For a patient with unilateral submandibular gland swelling from a suspected salivary stone, begin immediate conservative management with warm compresses, aggressive hydration, gentle gland massage, sialagogues (lemon drops or sour candies), and antibiotics if bacterial infection is suspected. 1, 2

Clinical Presentation

The diagnosis of sialolithiasis is strongly suggested by:

• Pain and swelling that characteristically occurs just before or during eating as salivary flow is stimulated but blocked 2
• Unilateral submandibular involvement (the most commonly affected gland in 80% of cases) 2, 3
• Palpable stone on bimanual examination or intraoral inspection of the duct 1

Initial Diagnostic Approach

Ultrasound is the first-line imaging modality for evaluating submandibular gland pathology due to its effectiveness, safety, and accessibility 1, 2, 4. This should be performed after:

• Intraoral inspection and bimanual palpation to identify stones in the duct or gland 1
• Assessment of salivary flow from the affected duct 2

CT with contrast is reserved for cases where bone involvement is suspected, calcifications need evaluation, or rapid assessment is needed 2. MRI with contrast provides superior soft tissue resolution if a tumor or complex mass requires detailed characterization 1.

Conservative Management Protocol

Initial treatment focuses on relieving obstruction and preventing infection:

Immediate Measures

• Apply warm compresses to the affected submandibular area 1, 2
• Ensure aggressive hydration to promote salivary flow 1
• Perform gentle massage of the salivary gland, milking the duct from posterior to anterior 1, 3, 5
• Administer sialagogues such as lemon drops or sour candies to stimulate saliva production 1, 2

Antibiotic Therapy

• Prescribe appropriate antibiotics if bacterial infection (sialadenitis) is suspected, particularly if there is fever, purulent discharge, or significant inflammation 1

When Conservative Management Succeeds

Small, easily accessible stones (typically <5mm) may be managed successfully with these conservative methods alone 3, 5. The stone may be "milked" out of the duct with continued conservative therapy 3, 5.

Indications for Surgical Referral

Refer to oral/maxillofacial surgery when:

• Stones are large (>10mm), inaccessible, or located deep within the gland 2, 3, 6, 5
• Conservative therapies fail after an appropriate trial 6, 5
• Multiple stones are present 6, 7
• Recurrent episodes occur despite conservative management 2

Surgical options include intraoral stone removal for accessible anterior duct stones or complete gland excision for large intraglandular stones 3, 8, 6.

Critical Monitoring

Watch for complications requiring urgent intervention:

• Signs of airway compromise from significant gland swelling 1
• Abscess formation requiring drainage 1
• Neurologic complications including facial nerve injury (particularly the marginal mandibular branch) 1

Common Pitfalls to Avoid

• Do not delay imaging if the stone is not palpable—ultrasound can identify non-palpable stones and assess glandular architecture 2, 4
• Do not assume bilateral swelling is sialolithiasis—bilateral involvement suggests sarcoidosis, Sjögren's syndrome, or IgG4-related disease and requires different workup 4
• Do not perform CT as first-line imaging—ultrasound is preferred initially unless specific indications exist 1, 2

Most patients with properly managed submandibular sialolithiasis achieve complete or near-complete recovery with either conservative management or surgical intervention 1.