Sialoadenitis is the medical term for the inflammation of one or more salivary glands, the organs responsible for producing saliva. The body has three pairs of major salivary glands: the parotid glands (in front of each ear), the submandibular glands (beneath the jaw), and the sublingual glands (under the tongue). This condition most frequently affects the parotid and submandibular glands. Sialoadenitis can manifest as an acute, sudden inflammation or a chronic, long-term condition, often related to a disruption in the normal flow of saliva.
Understanding the Causes and Risk Factors
The inflammation associated with sialoadenitis often stems from infectious agents, with bacterial and viral sources being the most common causes. Bacterial infections typically occur when the flow of saliva is reduced or blocked, allowing bacteria from the mouth to travel backward into the gland. The most frequently isolated bacterial organisms are Staphylococcus aureus and various Streptococcus viridans species, although the infection is often polymicrobial. Viral causes are also significant, with the mumps virus historically being the most recognized pathogen, especially for affecting the parotid gland.
Non-infectious factors often cause an obstruction or a reduction in saliva production. Sialolithiasis, or the formation of salivary stones within the duct, is a common mechanical cause, especially in the submandibular gland where the ducts are longer. Other contributing factors include severe dehydration, which decreases saliva volume, and poor oral hygiene, which increases the bacterial load in the mouth.
Individuals with chronic illnesses, such as Sjögren’s Syndrome or diabetes, face a higher risk due to compromised immune function or reduced salivary flow. The elderly and patients recovering from surgery are also prone to the condition, often because of dehydration or inability to maintain good oral hygiene. Certain medications, including antihistamines, diuretics, and some psychiatric drugs, can reduce saliva production, creating a dry mouth environment that encourages bacterial growth.
Recognizing the Signs and Symptoms
Sialoadenitis begins with swelling and pain in the affected gland. Patients commonly experience tenderness, often felt near the ear (parotid gland) or beneath the jaw (submandibular gland). This swelling may become worse during or immediately after eating, as the gland attempts to secrete saliva against an obstruction or inflammation.
If the condition is caused by a bacterial infection, systemic symptoms will often accompany the localized pain. Fever and chills can develop, indicating a spreading infection. The skin overlying the inflamed gland may appear red and feel warm to the touch, and in more severe cases, pus may drain from the salivary duct into the mouth, resulting in a foul taste.
Acute sialoadenitis presents with a rapid onset of severe pain and swelling. Chronic sialoadenitis involves repeated episodes of swelling that may be less painful and often occur without the pronounced redness and tenderness seen in acute infections.
Diagnosis and Management of Sialoadenitis
Diagnosis begins with a physical examination and a review of the patient’s medical history. The clinician will feel the affected area for firmness and tenderness and may gently massage the gland to check for pus or thick saliva emerging from the duct, which can be sent for culture to identify bacteria.
Imaging studies are frequently necessary to confirm the cause or check for complications. An ultrasound is commonly used to visualize the gland, detect a salivary stone (sialolith), or identify an abscess. Computed tomography (CT) scans may be ordered for a more detailed evaluation of the gland’s structure, especially if a deep-seated infection is suspected.
Mild or viral cases are managed with conservative measures focused on promoting salivary flow and relieving symptoms. This approach includes ensuring adequate hydration, applying warm compresses to the swollen area, and gently massaging the gland.
Sucking on sialogogues, such as lemon drops or sour candies, is often recommended to stimulate saliva production, which can help flush out the duct. Pain relief is typically achieved with common non-steroidal anti-inflammatory drugs (NSAIDs).
When a bacterial infection is confirmed or strongly suspected, a course of antibiotics is started, often targeting the most common organisms like Staphylococcus aureus. In severe bacterial cases, particularly those involving significant dehydration or systemic illness, hospitalization for intravenous antibiotics and fluids may be required. If an abscess develops, surgical drainage becomes necessary to prevent the infection from spreading to deep neck tissues.
For recurrent or obstructive cases caused by a salivary stone, sialendoscopy is used. This minimally invasive technique involves inserting a tiny endoscope into the salivary duct to directly visualize and remove smaller stones or dilate narrowed ducts. Larger or inaccessible stones may require traditional surgical removal or, in chronic cases unresponsive to other treatments, the complete removal of the affected salivary gland.