Many different problems can interfere with the function of the salivary glands or block the ducts so they can't drain saliva. The following are some of the more common salivary gland problems:
Salivary stones, or sialoliths. The most common cause of swollen salivary glands, salivary stones are buildups of crystallized saliva deposits. Sometimes salivary stones can block the flow of saliva. When saliva can't exit through the ducts, it backs up into the gland, causing pain and swelling. Pain is usually off and on, is felt in one gland, and gets progressively worse. Unless the blockage is cleared, the gland is likely to become infected.
Salivary gland infection, or sialadenitis. Bacterial infection of the salivary gland, most commonly the parotid gland, may result when the duct into the mouth is blocked. Sialadenitis creates a painful lump in the gland, and foul-tasting pus drains into the mouth.
Sialadenitis is more common in older adults with salivary stones, but it can also happen in babies during the first few weeks after birth. If not treated, salivary gland infections can cause severe pain, high fevers, and abscess (pus collection).
Infections. Viral infections such as mumps, flu, and others can cause swelling of the salivary glands. Swelling happens in parotid glands on both sides of the face, giving the appearance of 'chipmunk cheeks.'
Cysts. Cysts can develop in the salivary glands if injuries, infections, tumors, or salivary stones block the flow of saliva.Some babies are born with cysts in the parotid gland due to a problem with the development of the ears. It can appear as a blister or soft, raised area. Cysts may interfere with eating and speaking.
Tumors. Several different types of tumors can affect the salivary glands. They can be cancerous (malignant) or noncancerous (benign). The two most common tumors are pleomorphic adenomas and Warthin's tumor.
Sjögren's syndrome. This is a chronic autoimmune disease in which cells of a person's immune system attack the salivary and other moisture-producing glands, leading to dry mouth and eyes.
About half of people with Sjögren's syndrome also have enlargement of the salivary glands on both sides of the mouth, which is usually painless.