Sialoadenitis is a general term describing inflammation of any salivary gland. The three major salivary gland pairs are the parotid, submandibular, and sublingual. There are also numerous smaller salivary glands that empty into the oral cavity and all are capable of becoming inflamed. Salivary gland disorders have numerous causes, including acute and chronic infections; metabolic, systemic, and endocrine disorders; infiltrative processes; obstructions; allergic inflammation; and neoplastic diseases. Key features in the history are the duration and course of the symptoms, complaints of pain, and unilateral or bilateral location.
Both viral and bacterial infections of the salivary gland can produce enlarged, swollen, painful masses. Suppurative sialoadenitis is most commonly caused by S aureus and occurs in patients who are elderly, diabetic, or have poor oral hygiene. It may also follow episodes of dehydration, such as those due to surgery or debilitation. Viral sialoadenitis, such as mumps, the most common cause of nonsuppurative parotitis, or HIV, is the most common cause of sialoadenitis. It occurs with a concomitant general viral illness and is usually bilateral, whereas bacterial infections are primarily unilateral.
Suppurative Parotid Sialoadenitis. Fever, swelling, and tenderness over the parotid gland along with purulent discharge expressed from Stensen duct suggest suppurative parotid sialoadenitis. (Photo contributor: Lawrence B. Stack, MD.)
Suppurative Parotid Sialoadenitis. Pus from Stensen duct confirms suppurative parotid sialoadenitis. (Photo contributor: Lawrence B. Stack, MD.)
Suppurative Submandibular Sialoadenitis. Unilateral submandibular swelling. (Photo contributor: Jeffery D. Bondesson, MD.)
Sialolithiasis. A stone is seen at the orifice of Wharton duct. Small ranula are also seen at the tongue base. (Photo contributor: David Effron, MD.)
Obstructive sialoadenitis occurs from a calculus in the salivary gland or duct, most commonly in the submandibular gland. The flow of saliva becomes obstructed, causing swelling, pain, and firmness. Patients with sialolithiasis note general xerostomia and recurrent worsening of swelling and pain during eating.
A thorough head and neck examination is essential, especially a bimanual examination of the major salivary glands. In suppurative sialoadenitis, purulent drainage may be expressed from the submandibular duct (Wharton) or parotid duct (Stensen), and the glands are very tender and painful to examination. Sialolithiasis can manifest as enlargement of the ducts with minimal saliva expressed on stripping and, rarely, a palpable or visible stone or duct thickening. Facial radiographs are of limited utility. Ultrasound or CT may be useful to detect abscesses.
Suppurative Submandibular Sialoadenitis. After applying firm pressure, purulent discharge is seen coming from Wharton duct. (Photo contributor: Jeffery D. Bondesson, MD.)