Differential Diagnoses for Bilateral Parotid and Submandibular Gland Inflammation with Pharyngo-Laryngeal Extension

Primary Differential Considerations

The American Thoracic Society recommends considering sarcoidosis as a leading differential diagnosis given the bilateral salivary gland involvement, with parotid uptake on imaging considered "highly probable" for sarcoidosis diagnosis, and symmetrical parotid enlargement being a "probable" clinical feature 1
The American College of Rheumatology suggests that lacrimal glands may be bilaterally enlarged in patients with sarcoidosis, and biopsy shows non-caseating granulomas; special stains negative for mycobacteria and fungi 2
The European Respiratory Society notes that hypercalcemia/hypercalciuria with abnormal vitamin D metabolism supports the diagnosis of sarcoidosis, and elevated ACE level (>50% upper limit of normal) is a probable feature 1
The American Academy of Otolaryngology recommends considering Eosinophilic Granulomatosis with Polyangiitis (EGPA) as a differential diagnosis, particularly with pharyngeal involvement, with peripheral eosinophilia (>1500 cells/μL or >10%) being characteristic, and p-ANCA positivity in 26-48% of cases 3
The American College of Physicians suggests that Granulomatosis with Polyangiitis (GPA) is part of the differential for granulomatous diseases, distinguished from EGPA by absence of marked eosinophilia and asthma, with c-ANCA positivity more common than in EGPA 3

The Infectious Diseases Society of America recommends considering other granulomatous conditions, including tuberculosis (requires special stains for mycobacteria), syphilis, rhinoscleroma, fungal diseases, berylliosis, and leprosy, as part of the differential diagnosis 2

The American Cancer Society notes that lymphoma should be considered with bilateral involvement and lymphadenopathy, with intraglandular lymphatic tissue predisposing parotid glands to lymphoma, and fever, weight loss, night sweats suggesting lymphoma 5

The American College of Radiology recommends initial imaging with CT neck with contrast, and additional imaging with MRI neck with and without contrast for better soft tissue characterization, and chest CT to evaluate for pulmonary sarcoidosis or EGPA if indicated 6
The American Academy of Otolaryngology suggests that tissue diagnosis is essential, with fine needle aspiration or core biopsy of affected glands, and histology to identify non-caseating granulomas (sarcoidosis), IgG4+ plasma cells, or vasculitis 2