From the Guidelines
Parotitis is primarily caused by viral infections, with mumps virus being the most common culprit, as evidenced by the significant decline in mumps cases following the introduction of the Jeryl Lynn strain mumps vaccine in 1967 1. The causes of parotitis can be multifaceted, including:
- Viral infections, such as mumps, which has been largely controlled through vaccination, with a 99% decline in reported cases in the United States 1
- Bacterial infections, typically caused by Staphylococcus aureus and anaerobic bacteria
- Autoimmune conditions like Sjögren's syndrome
- Obstructive issues such as salivary stones or duct strictures
- Side effects of certain medications, particularly those causing dry mouth
- Surgical procedures
- Dehydration, which reduces saliva flow and allows bacteria to multiply in the gland
- Radiation therapy to the head and neck region, which may damage the parotid gland and lead to inflammation
- Poor oral hygiene, contributing to bacterial ascension into the gland
- Immunocompromised states, increasing susceptibility to infections that can cause parotitis It is essential to consider these various causes for proper diagnosis and treatment of parotid gland inflammation, and to prioritize vaccination against mumps, as supported by the high vaccine coverage in the United States, with approximately 91.5% of children aged 19–35 months having received 1 dose of MMR vaccine in 2010 1. In evaluating parotid region abnormalities, CT face and/or neck with IV contrast is commonly used, particularly in cases of suspected parotid acute inflammation, as noted in the 2019 study on ACR Appropriateness Criteria for neck mass-adenopathy 1.
From the Research
Causes of Parotitis
The causes of parotitis, which is the inflammation of the parotid gland, can be categorized into viral and bacterial infections.
- Viral parotitis can be caused by paramyxovirus (mumps), Epstein-Barr virus, coxsackievirus, and influenza A and parainfluenza viruses 2.
- Bacterial parotitis is generally caused by Staphylococcus aureus, Streptococcus species, and rarely, gram-negative bacteria, as well as anaerobic bacteria such as Peptostreptococcus species and Bacteroides species 2, 3.
Predisposing Factors
Predisposing factors to suppurative infections include:
- Dehydration
- Malnutrition
- Oral neoplasms
- Immunosuppuration
- Sialolithiasis
- Medications that diminish salivation 2
Other Causes
Other causes of parotitis include:
- Mycobacterium tuberculosis and atypical mycobacteria, although these are rare causes 3
- Decreased salivary flow or obstruction, which can lead to chronic parotitis 4
Diagnosis and Management
Diagnosis and management of parotitis involve assessing the disease process, differentiating between local primary parotid infection and systemic infection, and using laboratory and radiographic tools to aid in diagnosis 2, 4, 5, 6.