The patients suffering from sialadenitis generally experience redness, swelling and pain in the affected side of the mouth. This occurs due to the enlargement of gland as a result of inflammation caused by bacteria or virus infection. The swelling may become enormously enlarged, sometimes even reaching the size of an orange, with overlying inflamed reddened skin and edema. Mild pain and swelling are usually common before and during meals. Fluctuation test may be positive in the swelling if it is filled with fluid. Other symptoms of sialadenitis include a foul taste in the mouth, decreased mobility in the jaw, dry mouth, skin changes, weight loss, shortness of breath, keratitis, dental pain, skin discharge and lymphadenopathy. The patient may run fever with rigors and chills along with malaise and generalized weakness as a result of septicemia. In severe cases, pus can often be secreted from the duct by compressing the affected gland. The duct orifice is reddened with reduced flow. There may or may not be a visible or palpable stone.

The diagnosis of salivary gland swelling begins with careful thorough history and general physical examination.

• History: The patient is asked in detail about the onset and duration of symptoms, history of recent operations or recent dental procedures, past medical and surgical history, history of radiation therapy, drug history and immunization history.
• General physical examination: On physical examination, the gland with its duct should be palpated for the presence of calculi. The floor of mouth as well as the lips, cheek, gums, tongue and neck are also examined. A quick cranial nerve examination should also be done.
• Laboratory studies for confirmation of the diagnosis include the following.
• Complete blood count: This should be obtained if the patient experiences septicemia. White blood cell count are elevated in the presence of infection.
• Blood culture and sensitivities: The exudate from duct is taken to test bacterial growth in the presence of infection.
• Soft tissue radiographs: These help to diagnose stones in the salivary duct.
• Ultrasound of gland: It demonstrates a sialolith or a fluid-filled abscess cavity in chronic infections [9].
• CT scan: It demonstrates enlarged salivary gland in chronic sclerosing sialadenitis [10].
• Magnetic resonance imaging: It is of little help in sialadenitis or sialolithiasis as it may miss an obstructing stone. However, it is helpful in evaluating suspected neoplasia of the salivary glands.
• Scintigraphy using radioisotope Tc-99m: It may show the presence of hypo-functioning or non-functioning salivary gland.
• Sialography: It is used to evaluate sialolithiasis as well as inflammatory or neoplastic diseases [11] [12].
• Fine needle aspiration and biopsy: It should be undertaken if a solid neoplasm is suspected in subacute sclerosing sialadenitis [13] [14].
• Sialoendoscopy: It is a new technique to visualize sialoliths, polyps, foreign bodies, anatomic malformations and ductal structures.
• Moreover, routine electrolytes and serum analysis for antinuclear antibody should be obtained to assess dehydration or systemic infection.

Sialadenitis can be treated through proper oral hygiene. If left untreated, it can lead to severe complications and abscess formation. Treatment of sialadenitis includes the following.

• Home remedies: Some cases can be effectively treated with home remedies like good oral hygiene, drinking plenty of water, warm-water rinses, massaging the area, warm compresses, use of analgesics, topical application of ice cubes and sialogogues like a sour candy or chewing gum to stimulate the secretion of saliva. With conservative management, the symptoms subside over a period of few weeks.
• Medical management: For acute bacterial infections, general supportive care with broad-spectrum antibiotics is given. Intravenous antibiotics are given for the first 48 hours and then switched to an oral alternative if clinically improved. Beta lactams or vancomycin are generally considered the first-line drugs. Clindamycin or metronidazole are acceptable alternatives. NSAIDS and corticosteroids have also been effective.
• In case of abscess formation, surgical incision and drainage is required. Care must be taken to avoid injury to the facial nerve. 
• Surgical management: Operative management is indicated for salivary duct stone. It involves cannulation of salivary duct with stone removal. The procedure can be performed under general anesthesia. In severe cases with more than 3 attacks per year, complete surgical excision of the gland may be recommended. Sialendoscopy is a safe, efficacious and gland-preserving procedure used as a first-line therapy for stones in the distal ducts for both the submandibular and parotid glands. Extracorporeal shock wave lithotripsy under ultrasound guidance can also be used for stones within the glandular ducts. In patients with symptomatic chronic sclerosing sialadenitis, removal of the whole affected gland is recommended. However, the patients with autoimmune sialadenitis often require medical management of the underlying cause such as Sjogren syndrome.

The prognosis depends on the etiology of the inflammation. With prompt diagnosis and appropriate treatment, the outlook is very good. If treated with appropriate antibiotics, acute bacterial sialadenitis should settle within a week; however, mild swelling may persist. If sialoliths are surgically treated, the prognosis is good. Recovery is typically over a 3 to 6 month period and is usually complete. If left untreated, the disease may recur and can lead to chronic sclerosing sialadenitis [7] [8]. Chronic sialadenitis is usually resistant to treatment and can lead to abscess formation.

There are many casual factors for sialadenitis but the most common of them is bacterial infection, especially Stapylococcal infection [3]. Other bacteria include streptococci, coliforms and various anaerobic species [4]. The major salivary glands affected are parotid, submandibular and sublingual glands. It typically occurs in elderly people but is also common in infants and adults. It usually affects chronically ill patients with xerostomia, patients with Sjogren syndrome, patients who have had radiation therapy to the oral cavity or radioactive iodine therapy for thyroid cancer and young adults with anorexia [5] [6]. The other predisposing factors include sialolithiasis, decreased salivary flow due to dehydration, post-operative conditions and drugs, poor oral hygiene, malnourishment and exacerbation of low grade chronic sialadenitis.

The incidence of community-acquired acute bacterial sialadenitis is unknown. However, 0.01% to 0.02% of patients admitted to hospital and 0.02% to 0.04% of post-surgical patients develop this condition. Although the majority of patients are older people, sialadenitis may also affect neonates, premature infants and young children. There is no race or sex predilection. Involvement of the submandibular gland is suggested to constitute approximately 10% of all cases of sialadenitis of the major salivary glands. Salivary stones causing sialadenitis are found with greatest frequency, approximately 63- 95% of cases in the submandibular gland. These are commonly formed between the age of 20 to 50 years. Chronic recurrent sialadenitis occurs ten times more frequently in adults than in children.

There are numerous salivary glands in the oral cavity but the major ones include the parotid gland, submandibular gland and sublingual gland. Each person makes a half to two liters of saliva daily, of which more than 90 percent comes from the major salivary glands. The minor salivary glands are located in the lips, cheeks and throat. They serve numerous functions including lubrication, production of hormones, enzymatic degradation of food substances, mediation of taste, antibody production and antimicrobial protection. A salivary gland is like a cluster of grapes with the “stem” being the duct through which saliva travels into the mouth. The salivary flow is regulated through the autonomic nervous system, most importantly, the parasympathetic division. The saliva is produced in the glandular subunit - the acinus. Upon contraction of myoepithelial cells, located along the periphery of the acinus, the saliva is secreted into the salivary ducts. If the flow is reduced or blocked due to some reason, there is a backflow resulting in accumulation of saliva behind the blockage. Due to bacterial growth, the salivary gland becomes enlarged with overlying skin redness and severe pain. This results into the inflammation of salivary gland, known as sialadenitis.

A salivary duct stone may also reduce the flow of saliva through the duct. The condition is called sialolithiasis. It usually occurs suddenly and unilaterally but can sometimes occur on both sides. It is composed mainly of calcium phosphate and calcium carbonate. A salivary stone may be a few millimeters to about two inches in size. The degree of inflammation depends on the size and location of the stone. The presence of a stone makes the gland swollen, inflamed, hard and painful due to the increased viscosity of stored secretions.

The most effective way to prevent sialadenitis and its recurrence is to pay attention to proper dental care and oral hygiene. The disease may not be cured but the symptoms can be controlled with a good oral routine. Patients requiring management should be monitored on a daily basis; preferably twice a day. They should be encouraged to drink plenty of water and fluids during the illness and especially after surgery. Patients with xerostomia should also increase water intake. Moreover, as increased production of saliva can prevent sialadenitis and sialoliths, sour candy and appropriate beverages should be taken to stimulate production of saliva. Salivary stones identified by routine X-rays must be removed immediately. Massaging of the affected gland or dilatation of the duct with lacrimal probe is found to be helpful in removing superficial salivary stones.

Sialadenitis is the inflammation of a salivary gland. It is caused by a bacterial infection, usually from Staphylococcus aureus. It is characterized by painful swelling of the gland, reddened overlying skin, tenderness, low grade fever, malaise and edema of cheek, periorbital region and neck. It may be classified into acute, chronic and recurrent forms [1]. Submandibular gland is the most commonly affected, usually due to an obstructing stone or hyposecretion of the gland [2]. It is most common among the elderly, although it can affect people of all ages, including infants. It is treated with antibiotics.

Sialadenitis is inflammation of a salivary gland. It most commonly affects parotid and submandibular gland. These glands produce saliva and help in lubrication and digestion of food. Inflammation is caused by bacterial infection or obstruction by a salivary stone. The patients usually present with enlarged, swollen and painful salivary gland. With proper treatment and good oral hygiene, the disease has a good prognosis.

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