The Swollen Parotid Gland

Several systemic diseases and local inflammatory processes can cause diffuse enlargement of the parotid gland. Clinical information regarding the patient's age, localization (including laterality), duration, clinical course of the disease, and presence of associated symptoms can aid in determining the diagnosis. CT and MRI features that help narrow the differential diagnosis include the appearance of the gland (homogeneous, single, or multiple masses); inflammatory changes in, or adjacent to, the parotid gland; pattern of disease spread to adjacent spaces; and the presence of lymphadenopathy. In some cases, imaging is used to monitor treatment response, progression of disease, and identify complications. Some of the diseases/conditions that produce diffuse enlargement of a parotid gland include Sjögren syndrome, sarcoidosis, IgG4 disease, benign lymphoepithelial lesions of HIV, sialolithiasis, sialosis, and Rosai-Dorfman syndrome.