Sialadenitis is infection of the salivary glands. This is a relatively common disease. Sialadenitis can be acute, subacute, or chronic in nature and can be of bacterial or viral origin. Bacterial infections may reach the salivary gland tissue mostly via the ductal system, whereas viral infections invade the salivary glands via the bloodstream. The incidence of bacterial sialadenitis is in direct relation to factors such as old age, nutritional and health status, trauma, anatomic abnormalities, and use of drugs that decrease the salivary flow. There are several etiological predisposing local and systemic generalized factors that play an important role in the development and course of sialadenitis (Table 9.1).

ACUTE BACTERIAL SIALADENITIS

Acute bacterial sialadenitis is also known as suppurative sialadenitis and mainly affects the parotid and submandibular glands. Sialadenitis of the intraoral and sublingual glands is very rare. This may be due to the fact that the serous saliva produced by the parotid gland has less bacteriostatic activity or may result from a secretory disorder that changes the amount and chemical composition of saliva, including most of the protein, mucins, and electrolytes. Primary acute bacterial parotitis (ABP) has been reported mainly in elderly patients suffering from dehydration, malnutrition, Sjogren's disease, poor oral hygiene, ductal obstructions due to sialolithiasis, tumor or foreign bodies, chronic tonsillitis, dental infection, neoplasm of the oral cavity, liver cirrhosis, or diabetes mellitus.