parotitis Commonly caused by a retrograde bacterial infection as a result of illness, sepsis, trauma, surgery, reduced salivary flow due to medications, diabetes, malnutrition and dehydration. Classically symptoms of painful swelling in the parotid region when eating seen. Management is based upon antibacterials, rehydration combined with gentle massage to encourage salivary flow. Chronic bacterial parotitis A latent infection despite clinical resolution of the disease resulting in impaired function. Histologically glandular duct dilation, abscess formation and atrophy may be seen. Parotid secretions are viscous. Disease course shows pain and swelling, waxing and waning. Radiographic screening should be undertaken to rule out sialolith. Management with palliative care with parotidectomy as a last resort. Viral infections Mumps Acute non-suppurative disease that often occurs in epidemics. Prevented by MMR vaccine. Caused by paramyxovirus that is transmitted by infected saliva and urine. A prodromal period of 24–28 hours is experienced, followed by rapid and painful swelling of the parotid gland. Treatment is supportive (bedrest, hydration) as spontaneous resolution occurs within 5–10 days. HIV / AIDS Diffuse gland enlargement is seen, and may affect patients throughout all stages of the infection. Lymphoepithelial cysts seen via imaging help aid diagnosis. Pathogenic process occurs due to circulating CD8 lymphocytes within the salivary gland. Medical management via use of antiretrovirals, excellent oral hygiene measures and sialogogues. Autoimmune related Systemic lupus erythematosus Most commonly seen in fourth and fifth decades in women, and can affect any salivary gland. Presentation is a slowly enlarging gland, with diagnosis made by identification of the underlying systemic disorder and measurements of salivary chemical levels. Sodium and chloride ion levels will be elevated two or three times normal levels. Treatment is by addressing the underlying systemic condition. Sarcoidosis Sarcoidosis is a chronic systemic disease characterised by the production of non-caseating granulomas of unknown aetiology. It can affect any organ of the body, depressing cellular immunity and enhancing humoral immunity. Salivary gland involvement primarily involves the parotid gland, causing enlargement and swelling. Salivary gland biopsy with histopathologic examination is needed to make the distinction between whether Sjoren’s syndrome or sarcoidosis is the cause of this. Sjogren's syndrome Salivary gland enlargement occurs in up to 30% of patients with Sjogren’s syndrome, with the parotid gland being most often enlarged, and bilateral parotid gland enlargement seen in 25–60% of patients. However, the parotid glands have a longer-lasting secretory capacity in Sjogren’s syndrome patient and therefore are the last