Parotitis is an inflammation of one or both parotid glands, the major salivary glands located on either side of the face, in humans. The parotid gland is the salivary gland most commonly affected by inflammation.

Etymology

From Greek παρωτῖτις (νόσος), parōtĩtis (nósos) : (disease of the) parotid gland < παρωτίς (stem παρωτιδ-) : (gland) behind the ear < παρά - pará : behind, and οὖς - ous (stem ὠτ-, ōt-) : ear.

Causes

Dehydration

Dehydration:

This is a common, non-infectious cause of parotitis. It may occur in elderly or after surgery.

Infectious

Acute bacterial parotitis:

is most often caused by a bacterial infection of Staphylococcus aureus but may be caused by any commensal bacteria. Parotitis presents as swelling at the angle of the jaw. Bacterial parotitis presents as a unilateral swelling, where the gland is swollen and tender and usually produces pus at the Stensen's duct. This pus is usually sampled and the bacteria within are identified. Common causative bacteria are Staphylococcus aureus, Streptococcus pyogenes and E. coli. It is associated with poor oral hygiene; oral infections and decreased saliva production. Symptoms include fever, dehydration, chills, fast heartbeat and breathing if the infection is causing sepsis. Medications such as antihistamines and diuretics can be predisposing factors. Treatment is usually antibiotics.

Parotitis as extrapulmonary tuberculosis:

The mycobacteria that cause tuberculosis can also cause parotid infection. Parotid swelling can be an uncommon symptom of extrapulmonary tuberculosis (TB outside of the lungs). The usual symptoms are a cough, fever, weight loss, shortness of breath, chest pain, tiredness and chills. This is caused by the bacterium Mycobacterium tuberculosis. TB can also affect the heart, thyroid and adrenal glands but the main site of infection is the lungs. Risk factors are chronic alcohol consumption, diabetes, long term steroid use, HIV infection and kidney failure.

HIV parotitis: Generalized lymphadenopathy has long been associated with HIV, but the localized enlargement of the parotid gland is less well known. HIV-associated salivary gland disease can involve many diseases but often presents as enlargement of the parotid gland and a dry mouth. Causes have not been specifically identified but the most likely are viral opportunists and autoimmune responses. Viruses linked to this can include; hepatitis C, cytomegalovirus, paramyxovirus, influenza A, and adenovirus. Treatment is anti-retroviral therapy.

Disseminated histoplasmosis: During a large urban disseminated histoplasmosis outbreak (est. 100,000 victims) in Indianapolis from 1978 to 1979, manifestations included parotitis.

Autoimmune

These are also collectively known as chronic punctate parotitis or chronic autoimmune parotitis.

Sjögren's syndrome:

Chronic inflammation of the salivary glands may also be an autoimmune disease known as Sjögren's syndrome. The disease most commonly appears in people aged 40–60 years, but it may affect small children. In Sjögren syndrome, the prevalence of parotitis in women versus men is approximately 9:1. The involved parotid gland is enlarged and tender at times. The cause is unknown. The syndrome is often characterized by excessive dryness in the eyes, mouth, nose, vagina, and skin. Other causes can be duct stricture (narrowing of the duct), infection or injury. Symptoms may include recurrent swelling, pain and aggravation during eating as this is when saliva production is stimulated. Ductal obstruction may cause less saliva flow, which can result in recurrent gland infections.

Stones may be diagnosed via X-ray (with a success rate of about 80%

Sialadenosis (sialosis):

In this disorder, both parotid glands may be diffusely enlarged with only modest symptoms. Patients are aged 20–60 years at onset, and the sexes are equally involved. The glands are soft and non-tender. Approximately half of the patients have endocrine disorders such as diabetes, nutritional disorders such as pellagra or kwashiorkor, or have taken drugs such as guanethidine, thioridazine, or isoprenaline.

Sarcoidosis:

The lungs, skin, and lymph nodes are most often affected, but the salivary glands are involved in approximately 10% of cases. Bilateral firm, smooth, and non-tender parotid enlargement is classic. Xerostomia occasionally occurs. The Heerfordt-Waldenstrom syndrome consists of sarcoidosis with parotid enlargement, fever, anterior uveitis, and facial nerve palsy. was a term used when (i) any two of the parotid, submandibular and lacrimal glands were persistently and symmetrically enlarged and (ii) other diseases that may mimic this presentation were excluded.

Pneumoparotitis:

Air within the ducts of the parotid gland with or without inflammation. The duct orifice normally functions as a valve to prevent air from entering the gland from a pressurized oral cavity. Rarely, an incompetent valve allows insufflation of air into the duct system. Pneumoparotitis most commonly occurs in wind instrument players, glass blowers, and scuba divers.

Masseteric hypertrophy

Masseteric hypertrophy (enlargement of the masseter muscle's volume) can present as facial swelling in the parotid gland area and may be confused with 'true' parotid gland swelling. The specific cause of masseteric hypertrophy is still unclear, but it may be related to tooth grinding or malocclusion. Treatment options can include surgical removal of some of the muscle and botulinum toxin type A injections.

Diagnosis

Serum and urinary amylase rise during the first week of parotitis.

Treatment

Treatment is based on lab investigation report.

References

  • eMedicine