| Cause | Clinical features |
| Acute unilateral salivary gland swelling |
| Salivary gland stone | - Sudden onset of pain and swelling associated with eating
- Submandibular gland most common
|
| Acute bacterial sialadenitis | - Acute onset of pain and swelling
- Usually parotid gland
- Often with purulent discharge at duct orifice
- Typically affects older, medically debilitated patients
|
| External beam radiation sialadenitis | - Acute, painful swelling of salivary glands in the treatment field
- May be associated with decreased saliva production and diminished sense of taste
|
| Acute bilateral salivary gland swelling |
| Viral sialadenitis | - Usually affects parotid glands
- May be unilateral initially
- Usually tender
- Viral etiologies: mumps (most common), coxsackievirus A and B, echovirus, parainfluenza virus, influenza A, Epstein-Barr virus
|
| Human immunodeficiency virus | - Diffuse, symmetric, cystic enlargement
- Affects the major salivary glands, most commonly the parotids
- Usually non-tender
|
| Radioactive iodine radiation sialadenitis | - Acute painful swelling
- May be associated with decreased saliva production and diminished sense of taste
|
| Reaction to intravenous contrast | - Most commonly involves the submandibular glands
- Rare
|
| Chronic unilateral salivary gland swelling |
| Salivary gland tumors | - Subacute, painless enlargement of a single salivary gland
- Parotid gland more commonly affected than submandibular gland
- May be accompanied by facial nerve dysfunction
|
| Chronic bacterial sialadenitis | - Recurrent episodes of pain and swelling
- Parotid gland most commonly affected
- Occasionally bilateral
|
| Chronic bilateral salivary gland swelling |
| Sjögren's syndrome | - Gradual onset
- Affects parotid or submandibular glands
- Often associated with dry eyes and dry mouth
|
| Sarcoidosis | - Gradual onset of painless swelling
- Usually affects the parotid glands
- May be accompanied by uveitis or facial nerve paralysis
|
| Malnutrition | - Usually affects the parotid gland
- May be unilateral
|
