Acute inflammation of the salivary glands is...
Monday 18 March 2013
Acute inflammation of the salivary glands is usually of viral or bacterial origin.
Of the viral illnesses, mumps is the most common. This illness is caused by an RNA virus from the paramyxovirus group and typically involves the parotid glands bilaterally.
Children are most often affected with peak incidence at approximately 4 to 6 years of age. Transmission is via infected respiratory droplets.
The parotid swelling is accompanied by constitional symptoms such as fever and malaise, and many cases are mild and subclinical in nature.
Onset of symptoms usually follows a 2 to 3 week incubation period, and infection may be documented by a rise in convalescent serum titers to viral antigens or to isolation of the virus from the urine for a period from approximately 1 week prior to and 2 weeks after onset of symptoms.
Treatment is symptomatic. Serious sequelae are fortunately rare and often stem from involvement of other organ systems such as the CNS, pancreas, and gonads.
Salivary gland involvement may be seen in a wide range of other viral illnesses including those caused by cytomegalovirus, lymphocytic choriomeningitis virus, coxsackievirus A, echovirus, and parainfluenza virus type C among others. Again, treatment is symptomatic.
Acute suppurative sialadenitis is most commonly bacterial in origin and most often involves the parotid, and to a lesser extent, the submandibular glands. The more mucinous saliva produced by the submandibular glands is felt to confer more bacteristatic properties than the serous saliva of the parotids.
The causative agent most frequently implicated is Staphylococcus aureus. Other aerobic organisms isolated are Streptococcus pneumoniae, Hemophilus influenzae, and Escherichia coli. Anaerobic bacteria such as Bacteroides have been involved as well. Stasis of saliva, often as a result of dehydration, is thought to be an integral component in the pathogenesis of this condition perhaps secondary to obstruction or decreased production.
Common clinical settings in which this entity may occur include the elderly postoperative patient after cardiothoracic or gastrointestinal surgery and perhaps more frequently the elderly nursing home patient.
Onset is typically heralded by unilateral abrupt diffuse swelling of the parotid perhaps with accompanying induration and tenderness. Mucopurulent material may be expressed from the opening of Stensen’s duct with massage of the gland, and a sample should be obtained for Gram stain and culture. Fluctuance is often not present due to the multiple fascial investments with the substance of the parotid gland. Therapy is initially conservative with adequate hydration, sialogogues, heat, massage of the affected gland, and the administration of an appropriate intravenous antibiotic, usually a penicillinase-resistant antistaphylococcal antibiotic. Improvement is expected within the first 24 to 48 hours. If this does not occur, operative intervention may be indicated. This usually consists of a standard parotidectomy skin incision and flap followed by creation of several openings within the substance of the gland parallel to the course of the facial nerve. A drain is then placed over the gland and the wound closed. Complications include possible septicemia or deep space neck infection. Mortality has been reported as high as 20% and is likely related to the severity patient’s underlying medical condition.