Sialosis / Sialadenosis
Sialosis / Sialadenosis

What is it?

Sialadenosis’ is a non-specific term used to describe an
uncommon, benign, non-inflammatory, non-neoplastic
enlargement of a salivary gland, usually the
parotid gland
but occasionally affects the
submandibular glands and
rarely, the
minor salivary glands.

This enlargement is bilateral, symmetrical and painless (it
is often painless but not invariably so).

In general, the enlargement is asymptomatic and the cause

In this disorder, both
parotid glands may be diffusely
enlarged with only modest symptoms.  Patients are aged
30 - 69 years at onset and the sexes are equally involved.
The glands are soft and non-tender.
Photos of Sialosis / Sialadenosis

Several causes have been recorded, most of which are associated with (mal-)
nutrition, metabolism or drugs and have a unifying feature in
autonomic neuropathy.

Changes in
salivary aquaporin water channels may also be involved.


Among the wide range of drugs that may induce sialosis, anti-hypertensive agents
are prominent.

  • Alcohol abuse ± liver cirrhosis + hepatic steatosis and alcoholic hepatitis.
    (Previous reports have indicated that between 30% and 80% of patients with
    alcoholic cirrhosis have sialosis but, if that were universally true, one would
    expect sialosis to be seen more often than it is)
  • Sympathomimetics such as isoprenaline
  • Phenylbutazone
  • Anti-thyroids & phenothiazines

Endocrine (Hormonal)

  • Diabetes Mellitus (reported prevalence of sialosis in diabetes ranging from
    10% to 80%)
  • Pregnancy
  • Acromegaly
  • Following oophorectomy

Nutritional Disorders

Any disorder that affects the digestion of food or its absorption over a prolonged
period, can result in
sialosis, and malnutrition may contribute to sialosis in

  • Malnutrition - pellagra or kwashiorkor
  • Cystic Fibrosis & pancreatitis
  • Anorexia Nervosa
  • Bulimia

Multiple emetic episodes (bulimia) cause an autonomic neuropathy.  With
sympathetic nerve impairment, individual acinar cells enlarge because of zymogen
granule engorgement

One explanation is that the
sympathetic nerve supply to the secreting acinar cell is
concerned with the production and secretion of
zymogen, the precursor of
amylase.  Because of sympathetic nerve dysfunction, there may be an increase in
zymogen storage
in the cell, owing to increased production, decreased secretion of
the granules or both. The ensuing
cellular enlargement, which is evidenced by fine-
needle aspiration biopsy
and electron microscopy, leads to the clinically visible
gland enlargement.

Clinical Findings:

Soft, painless, general enlargement of both

Investigations & Imaging:

Blood Tests:

  • ↑ glucose levels
  • Abnormal liver function tests


  • ↑ potassium levels
  • ↑ calcium levels

Ultrasound, MRI & Sialography:

Helps differentiate space occupying lesions


Rarely indicated.  If done, the biopsy shows the
acinar cells to be enlarged to
almost twice the normal diameter and the
cytoplasm packed with enzyme granules.


None necessary.

Sialosis may resolve if diabetes mellitus- & alcoholism-related sialosis is treated

If the glands are disfiguring,
superficial parotidectomy to improve the appearance
could be considered (though seems a bit radical).  By the same token,
anorexic or
bulimic patients may attend seeking advice about surgical removal of the glands.  
anorexia or bulimia would need to be treated before any such surgery could be

Useful Website & Articles:


BSOM Patient Information Sheet. Sialosis

J Am Dent Assoc 1997.  Alcoholic parotid sialadenosis

J Oral Maxillofac Surg 2002.  Sialadenosis Associated With Diabetes Mellitus - A
Case Report

J Am Dent Assoc 2004.  Case report.  Diagnosing bulimia nervosa with parotid
gland swelling

J Oral Maxillofac Surg 2005.  Alcoholic (Beer) Sialosis

BJOMS 2008.  Sialosis - 35 cases of persistent parotid swelling from two countries
Last Updated 15th December 2014