EC Neurology

Salivary gland infection or inflammation of bacterial origin is designated as acute suppurative sialadenitis. Alternatively, the condition of viral sialadenitis may represent as mumps. Besides, viral infection may induce sialadenitis wherein infection with paramyxovirus may represent as mumps or viral sialadenitis.

Additionally designated as acute sialadenitis or bacterial sialadenitis, acute suppurative sialadenitis arises on account of ascending bacterial infection and contamination from the oral cavity in concurrence with impaired outflow of saliva.

Staphylococcus aureus is a common contributor to bacterial sialadenitis wherein parotid gland is frequently implicated. Generally, preterm infants or elderly population is affected. Acute suppurative sialadenitis is commonly encountered within preterm infants and elderly subjects wherein contributory factors as dehydration, salivary outflow obstruction with sialolithiasis, malnutrition, immunosuppression, chronic illness, diabetes mellitus and certain medications as anticholinergics may induce the condition [1,2]. Viral sialadenitis emerges on account of viral agents such as cytomegalovirus, coxsackievirus, herpes simplex virus, influenza A, parainfluenza, adenovirus and paramyxovirus which induces mumps. Viral sialadenitis constituting mumps arises preponderantly (~85%) in subjects < 15 years. Generally, bilateral parotid gland is implicated whereas up to 30% of post pubertal male subjects display epididymo-orchitis [1,2].

Mumps commonly occurs within a temperate climate and late winter or early spring season wherein the disease is associated with quantifiably significant proportion of disease. Mumps associated viral sialadenitis is posited to arise due to factors as immunocompromised state, international travel or absence of vaccination [2,3]. Appropriate immunization decimates frequency of infection with paramyxovirus inducing mumps. Besides, mumps is characteristically a bilateral disease [2,3].

Parotid gland frequently depicts occurrence of acute suppurative sialadenitis as the serous saliva appears minimally competent in circumventing bacterial infection of salivary gland, in contrast to mucoid rich saliva secreted from sublingual and submandibular glands. Bacterial and viral sialadenitis pre-eminently involves parotid gland [3,4].

Acute suppurative sialadenitis is posited to appear due to retrograde bacterial influx from the oral cavity with consequent contamination in concurrence with impaired outflow of saliva. Commonly, organisms such as Staphylococcus aureus emerge as the offending agent besides Streptococcal species and Haemophilus influenza [3,4].

Viral sialadenitis ensues on account of systemic infection induced by a virus, in contrast to direct salivary gland infection with the virus. Clinically, tender enlargement of implicated salivary glands is observed. Up to 30% post pubertal male subjects with mumps display epididymo-orchitis [3,4]. Acute suppurative sialadenitis and viral sialadenitis are commonly ascertained by cogent clinical symptoms and physical examination. Surgical tissue sampling is exceptionally required [4,5]. Salivary gland depicting acute suppurative sialadenitis expounds morphological alterations as oedema, hyperaemia and an acute inflammatory exudate infiltrating the salivary gland parenchyma. Viral sialadenitis expresses morphological features as diffuse interstitial oedema, intense hyperaemia and a dense infiltrate of lymphoid and histiocytic cells [4,5].

1. Ishiguro K., et al. “Bilateral sialadenitis as an uncommon initial manifestation of infectious mononucleosis”. Internal Medicine 63.22 (2024): 3105-3108.
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4. Balfour HH., et al. “Declining Epstein-Barr virus antibody prevalence in college freshmen strengthens the rationale for a prophylactic EBV vaccine”. Vaccines 10.9 (2022): 1399.
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9. Berta E., et al. “Role of sialendoscopy in juvenile recurrent parotitis (JRP)”. European Annals of Otorhinolaryngology, Head and Neck Diseases 134.6 (2017): 405-407.
10. Image 1 Courtesy: Wikipedia.
11. Image 2 Courtesy: NUS medicine.