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Sialosis or Sialadenosis of the Salivary Glands

last modified on: Thu, 11/09/2023 - 08:19

Sialosis or Sialadenosis of the Salivary Glands

see also: Sialosis or sialadenosis Case example of surgical treatment

return to: Salivary Swelling 

Sialosis (Sialadenosis) Sialogram

see also: Sialosis - Rads

Sialosis (sialadenosis) is a chronic, bilateral, diffuse, non-inflammatory, non-neoplastic swelling of the major salivary glands that primarily affects the parotid glands, but occasionally involves the submandibular glands and rarely the minor salivary glands (Scully 2008).  This can be painless or in some instances tender.

There are differing uses of the term 'sialosis' in the literature. Some consider 'sialosis' to be synonymous with 'sialadenosis'. Others - as per Katz et al (Katz 2009) employ sialosis as an umbrella term to 'designate all the chronic disease of the salivary glands that are not infections or tumors"

Sialosis may be idiopathic or may be associated with the following:

  1. chronic malnutrition
  2. obesity
  3. diabetes mellitus
  4. alcoholism
  5. liver disease
  6. eating disorders
  7. drugs (ie antihypertensives)
    (Duggan 1957 from Chen 2013)

From Chen et al (2013):
Authors (notably Merlo et al and Carda et al as cited by Chen) have identified different histopathology pictures in diabetic and alcoholic sialosis.
Diabetics with sialosis were found to have smaller acini, greater fatty infiltration in the glandular stroma, and normal-appearing epithelium.
Alcoholic sialosis identified a reduction in the proportion of fatty tissue of stroma with an enlargement in ductal epithelium felt to contribute to an increased caliber of the striated ducts. Also noted in alcoholic sialosis are accumulation of secretory granules in the acinar cells’ cytoplasm and enlarged excretory ducts

Mahler (1993) and Park (2009) identified that "Pilocarpine has proved to be beneficial in the treatment of sialadenosis in bulimic patients" and "This article presents a case of painful sialoadenomegaly associated with hyperamylasemia in a bulimic patient successfully managed with pilocarpine".

Among the drug or toxin exposure that has been associated with sialosis in the past Scully et al (Scully 2008) identified through literature review association of sialosis with

Antihypertensives  Lead 
Guanacline  Mercury 
Isoprenaline  Iodine 
Naproxen  Thiocyanate
Oxphenbutazone Thiouracil
Phenylbutazone Valproic acid

In the 35 cases reported by Scully et al, 4 patients were on antihypertensive medications - with 3 recorded as taking Ramipril also known as Altace (an angiotensin-converting enzyme (ACE) inhibitor)

Although fine needle biopsy or open biopsy has been supported by some to help establish the diagnosis, the clinical picture (coupled with radiographic imaging that may include ultrasound and/or CT,MRI,sialography) is sufficient to establish the diagnosis in the majority of cases.  Concern about tumor or processes other than sialosis may warrant a tissue diagnosis - with the novel approach proposed by Mignogna et el (2004) of doing a minor salivary gland biopsy through a palatal approach to confirm the diagnosis through findings of "hypertrophy of the acinar cells with small, round, and basally situated nuclei" along with 'areas of fatty infiltration"

Excellent updated summary from Bădărînză et al (2019) "sialosis (or sialoadenosis) a chronic, diffuse, non-inflammatory, non-neoplastic disease, associated with bilateral painless swollen parotid glands [Scully 2008]. The most common causes are chronic alcoholism, diabetes and obesity, but there are other incriminated rare conditions, such as malnutrition, bulimia or drugs [Scully 2008]. Histological evaluation found contradictory results about acinar enlargement and fatty infiltration [Merlo 1993]. The diagnosis is clinically suspected (enlargements of salivary glands) and is completed with US evaluation or, rarely, using biopsy to rule out other diagnosis [Orlandi 2013]. US examination shows homogenous, hyperechoic and enlarged salivary glands [Aria 2019]. To our knowledge, there are no available data regarding the salivary and lacrimal glands elastographic evaluation in patients with sialosis."


  1. Pape SA, MacLeod RI, McLean RN and Soames JV: Sialadenosis of the salivary glands. Brit J. of Plastic Surgery (1995), 48, 419-22
  2. Scully C, Bagan JV, Eveson JW, Barneard N, and Turner Fioan:  Sialosis: 35 cases of persistent parotid swelling from two countries. British Journal of Oral and Maxillofacial Surgery 46 (2008) 468-72
  3. Chen S, Benjamin C and Myssiorek D: An Algorithm Approahc to Diagnosin Bilateral Parotid EnlargementOtolaryngology – Head and Neck Surgery 148(5) 732-739
  4. Duggan J and Rothbell E: Asymptomatic enlargement of the parotid glands. NEJM 1957;257:1262-1267
  5. Carda C et al Structural and functional salivary disorders in type 2 diabetic patietns. Med oarl patol Oral Cir Bucal. 2006; 11:E 309-E314
  6. Merlo C et al Parotid sialosis: morphometrical analysis of the glandular parenchyme and stroma among diagbetic and alchoholic patients. J Oral Pathol Med. 2010;39:10-15
  7. Mehler PS and Wallace JA: Sialadenosis in bulimia. A new treatment Arch Otolaryngol Head Neck Surg. 1993 Jul;119(7):787-8.
  8. Park KK1, Tung RC, de Luzuriaga AR. Painful parotid hypertrophy with bulimia: a report of medical management. J Drugs Dermatol. 2009 Jun;8(6):577-9.
  9. Scully C1, Bagán JV, Eveson JW, Barnard N, Turner FM. Sialosis: 35 cases of persistent parotid swelling from two countries.Br J Oral Maxillofac Surg. 2008 Sep;46(6):468-72. doi: 10.1016/j.bjoms.2008.01.014. Epub 2008 Mar 17.
  10. Davis AB, Hoffman HT. Management Options for Sialadenosis. Otolaryngol Clin North Am. 2021 Jun;54(3):605-611. doi: 10.1016/j.otc.2021.02.005. PMID: 34024487.
  11. Mignogna MD, Fedele S, Lo Russo L. Anorexia/bulimia-related sialadenosis of palatal minor salivary glands. J Oral Pathol Med. 2004 Aug;33(7):441-2. doi: 10.1111/j.1600-0714.2004.00208.x. PMID: 15250838. 
  12. Orlandi MA, Pistorio V, Guerra PA. Ultrasound in sialadenitis. J Ultrasound 2013;16:3-9
  13. Arya S, Pilania A, Kumar J, Talnia S. Diagnosis of bilateral parotid enlargement (Sialosis) by sonography: A case report and literature review. J Indian Acad Oral Med Radiol 2019;31:79-83
  14. Badarinza M, Serban O, Maghear L, Bocsa C, Micu M, Porojan MD, Chis BA, Albu A, Fodor D. Multimodal ultrasound investigation (grey scale, Doppler and 2D-SWE) of salivary and lacrimal glands in healthy people and patients with diabetes mellitus and/or obesity, with or without sialosis. Med Ultrason. 2019 Aug 31;21(3):257-264. doi: 10.11152/mu-2164. PMID: 31476205.
  15. Katz P, Hartl DM, Guerre A. Clinical ultrasound of the salivary glands. Otolaryngol Clin North Am. 2009 Dec;42(6):973-1000, Table of Contents. doi: 10.1016/j.otc.2009.08.009. PMID: 19962004.