Differential Diagnosis for Parotid Gland Swelling
Single Most Likely Diagnosis
- Viral Parotitis (Mumps): This is often the first consideration due to its prevalence and the fact that it commonly causes parotid gland swelling, especially in children and young adults who are not vaccinated.
Other Likely Diagnoses
- Bacterial Parotitis: Typically seen in elderly or debilitated patients, it can cause significant swelling and pain in the parotid gland, often associated with fever and purulent discharge from the Stensen's duct.
- Sialadenitis: Inflammation of the salivary gland, which can be acute or chronic, and is often caused by bacterial or viral infections, leading to swelling of the parotid gland.
- Benign Salivary Gland Tumors (e.g., Pleomorphic Adenoma): These are common tumors of the salivary glands and can cause swelling of the parotid gland, usually presenting as a slow-growing, painless mass.
- Parotid Cyst or Mucocele: Fluid-filled lesions that can cause swelling of the parotid gland, often presenting as a painless, fluctuant mass.
Do Not Miss Diagnoses
- Parotid Malignancy (e.g., Mucoepidermoid Carcinoma, Adenoid Cystic Carcinoma): Although less common than benign tumors, malignant tumors of the parotid gland can present with swelling and require prompt diagnosis and treatment to improve prognosis.
- Sjögren's Syndrome: An autoimmune disorder that can cause inflammation and swelling of the parotid glands, among other symptoms, and is important to diagnose due to its systemic implications.
- HIV-Associated Parotid Swelling: Patients with HIV can experience parotid gland swelling due to various conditions, including lymphoepithelial cysts or diffuse infiltrative lymphocytosis syndrome (DILS), highlighting the importance of considering HIV status in the diagnostic workup.
Rare Diagnoses
- Sarcoidosis: A systemic granulomatous disease that can rarely cause swelling of the parotid gland as part of its manifestations.
- Wegener's Granulomatosis (Granulomatosis with Polyangiitis): A rare autoimmune disorder that can affect various organs, including the salivary glands, leading to swelling and other symptoms.
- Kimura Disease: A rare, chronic inflammatory disorder that can cause swelling of the parotid gland, often associated with lymphadenopathy and eosinophilia.