Malnutrition Medications Antihistamines Diuretics Tricyclic antidepressants Phenothiazines Antihypertensives Barbiturates Anti‐sialogogues Anticholinergics Chemotherapeutic agents Sialolithiasis Oral infection Non‐modifiable risk factors Advanced age Relatively non‐modifiable risk factors Radiation therapy where cytoprotective agents were not administered Renal failure Hepatic failure Congestive heart failure HIV/AIDS Diabetes mellitus Anorexia nervosa/bulimia Cystic fibrosis Cushing disease
General Considerations
Evaluation and treatment of the patient with sialadenitis begins with a thorough history and physical examination. The setting in which the evaluation occurs, for example a hospital ward vs. an office, may provide information as to the underlying cause of the infection. Many cases of acute bacterial parotitis (ABP) occur in elderly debilitated patients, some of whom are admitted to the hospital, who demonstrate inadequate intravenous fluid resuscitation (insufficient intake) or excessive volume loss (excessive output) (Figure 3.3) or third‐spacing of fluid resulting in hypovolemia. This notwithstanding, many cases of acute bacterial parotitis and submandibular sialadenitis are evaluated initially in an outpatient setting.
The formal history taking process begins by obtaining the patient's chief complaint. Sialadenitis commonly begins as swelling of the salivary gland with pain due to stretching of that gland's sensory innervated capsule. Patients may or may not describe the perception of pus associated with salivary secretions, and the presence or absence of pus may be confirmed on physical examination.
History taking is important to disclose the acute or chronic nature of the problem that will significantly impact on how the sialadenitis is ultimately managed. Regarding the prognosis and the anticipation for the possible need for future surgical intervention, an acute sialadenitis is somewhat arbitrarily classified as one where symptoms are less than one month in duration, while a chronic sialadenitis is defined as having been present for longer than one month. In addition, the history will permit the clinician to assess the risk factors associated with the condition. In so doing, the realization of modifiable versus relatively non‐modifiable versus non‐modifiable risk factors can be determined. For example, dehydration, recent surgery, oral infection, and some medications represent modifiable risk factors predisposing patients to sialadenitis. On the other hand, advanced age is a non‐modifiable risk factor, and chronic medical illnesses and radiation therapy constitute relatively non‐modifiable risk factors associated with these infections. The distinction between modifiable and relatively non‐modifiable risk factors is not intuitive. For example, dehydration is obviously modifiable. The sialadenitis associated with diabetes mellitus may abate clinically as evidenced by decreased swelling and pain; however, the underlying medical condition is not reversible. The same is true for HIV/AIDS. While much medical comorbidity can be controlled and palliated, these conditions often are not curable such that patients may be fraught with recurrent sialadenitis at unpredictable time frames following the initial event. As such, these and many other risk factors are considered relatively non‐modifiable.
Other features of the history, such as the presence or absence of prandial pain, may direct the physical and radiographic examinations to the existence of an obstructive phenomenon. The presence of medical conditions and the use of medications to manage these conditions are very important elements of the history taking of a patient with a chief complaint suggestive of sialadenitis. They may be determined to be of etiologic significance when the physical examination confirms the diagnosis of sialadenitis. Musicians playing wind instruments who present for evaluation of bilateral parotid swelling and pain after a concert may have acute air insufflation of the parotid glands as part of the “trumpet blower's syndrome” (Miloro and Goldberg 2002). Recent dental work, specifically the application of orthodontic brackets, may result in traumatic introduction of bacteria into the ductal system with resultant retrograde sialadenitis. Deep facial lacerations proximal to an imaginary line connecting the lateral canthus of the eye to the oral commissure, and along an imaginary line connecting the tragus to the mid‐philtrum of the lip may violate the integrity of Stensen duct. While a thorough exploration of these wounds with cannulation and repair of Stensen duct is meticulously performed, it is possible for foreign bodies to result in obstruction of salivary flow with resultant parotid swelling. Numerous autoimmune diseases with immune complex formation can also be responsible for sialadenitis, and confirmation of their diagnosis should be sought during the history and physical examination.
Figure 3.3. A 35‐year‐old man with a toxic megacolon (a) associated with Clostridium difficile diarrhea. He developed a left parotitis (b and c) due to a severe depletion of his intravascular volume.
After the patient's history has been obtained, the physical examination should be performed. In the patient with suspected sialadenitis, the examination is focused on the head and neck and begins with the extraoral examination followed by the intraoral examination. Specifically, the salivary glands should be assessed in a bimanual fashion for asymmetries, erythema, tenderness to palpation, swellings, induration, and warmth. In so doing, one of the most important aspects of this examination is to rule out the presence of a tumor (Carlson 2013). A neoplastic process of the parotid gland presents as a discrete mass within the gland, with or without symptoms of pain. An infectious process presents as a diffuse enlargement of the parotid gland that is commonly symptomatic. It is possible for an indurated inflammatory lymph node within the parotid gland to simulate neoplastic disease. The distinction in the character of the parotid gland is important to not waste time treating a patient for an infectious process when they have a tumor in the parotid gland, particularly in the event of a malignancy. Evidence of facial trauma, including healing facial lacerations or ecchymoses, should be ascertained. The intraoral examination focuses on the observation of the quality and quantity of spontaneous and stimulated salivary flow. It is important to understand, however, that the anxiety and sympathomimetic response associated with the examination is likely to decrease the patient's salivary flow. Nonetheless, an advanced case of sialadenitis will often allow the clinician to appreciate the flow of pus from the salivary ducts (Figures 3.4 and 3.5). If pus is not observed, mucous plugs, small stones, or “salivary sludge” may be noted. As part of the examination, it may be appropriate to perform cannulation of the salivary duct with a series of lacrimal probes (Figure 3.6). This maneuver may dislodge obstructive material or diagnose an obstruction. The decision to perform this instrumentation, however, must not be made indiscriminately. This procedure may introduce bacteria into the salivary duct that normally colonize around the ductal orifice, thereby permitting retrograde contamination of the gland. Prepping the Wharton duct or Stensen duct with a Betadine solution prior to lacrimal probe cannulation is therefore advised. This procedure is probably contraindicated in patients with acute bacterial parotitis and acute bacterial submandibular sialadenitis. The head and neck examination concludes by palpating the regional lymph nodes, including those in the preauricular and cervical regions.
Figure 3.4. A severe case of hospital acquired parotitis related to insufficient rehydration of this patient.