Sialadenitis usually occurs after hyposecretion or duct obstruction but may develop without an obvious cause. The major salivary glands are the parotid, submandibular, and sublingual glands.
Sialadenitis is most common in the parotid gland and typically occurs in
The most common causative organism is Staphylococcus aureus; others include streptococci, coliforms, and various anaerobic bacteria.
Inflammation of the parotid gland can also develop in patients who have had radiation therapy to the oral cavity or radioactive iodine therapy for thyroid cancer (1, 2, 3). Although sometimes described as sialoadenitis, this inflammation is rarely a bacterial infection, particularly in the absence of fever.
1. Erkul E, Gillespie MB: Sialendoscopy for non-stone disorders: the current evidence. Laryngoscope Investig Otolaryngol 1(5):140-145, 2016. doi: 10.1002/lio2.33.
2. An YS, Yoon JK, Lee SJ, et al: Symptomatic late-onset sialadenitis after radioiodine therapy in thyroid cancer. Ann Nucl Med 27(4):386-91, 2013. doi: 10.1007/s12149-013-0697-5.
3. Kim YM, Choi JS, Hong SB, et al: Salivary gland function after sialendoscopy for treatment of chronic radioiodine-induced sialadenitis. Head Neck 38(1):51-8, 2016. doi: 10.1002/hed.23844.
Initial treatment is with antibiotics active against S. aureus (eg, dicloxacillin, 250 mg orally 4 times a day, a 1st-generation cephalosporin, or clindamycin), modified according to culture results. With the increasing prevalence of methicillin-resistant S. aureus (MRSA) especially among the elderly living in extended-care nursing facilities, vancomycin is often required. Chlorhexidine 0.12% mouth rinses three times a day will reduce bacterial burden in the oral cavity and will promote oral hygiene.
Hydration, sialagogues (eg, lemon juice, hard candy, or some other substance that triggers saliva flow), warm compresses, gland massage, and good oral hygiene are also important. Abscesses require drainage.
Occasionally, a superficial parotidectomy or submandibular gland excision is indicated for patients with chronic or relapsing sialadenitis.
Mumps often causes parotid swelling (see Table: Other Causes of Parotid and Other Salivary Gland Enlargement).
Patients with HIV infection often have parotid enlargement secondary to one or more lymphoepithelial cysts.
Cat-scratch disease caused by Bartonella infection often invades periparotid lymph nodes and may infect the parotid glands by contiguous spread. Although cat-scratch disease is self-limited, antibiotic therapy is often provided, and incision and drainage are necessary if an abscess develops.
Atypical mycobacterial infections in the tonsils or teeth may spread contiguously to the major salivary glands. The PPD may be negative, and the diagnosis may require biopsy and tissue culture for acid-fast bacteria. Treatment recommendations are controversial. Options include surgical debridement with curettage, complete excision of the infected tissue, and use of anti-TB drug therapy (rarely necessary).