Salivary gland disorders, pathology Flashcards
Aplasia
- Failure to develop normally
- Of salivary glands is very rare. It may occur as an isolated event or as part of a hereditary syndrome (e.g Down syndrome)
Atresia
- Failure to be tubular
- of ducts is also very uncommon. Submandibular duct most often affected when it does occur
Heterotopic salivary tissue
Can be found at various sites in head and neck
What is a mucocoele ?
Is a cystic cavity filled with mucus
What are the two mucocoele ?
- Extravasation mucocoele (also called mucous extravascation cyst)
- Retention mucocoele (also called mucous retention cyst)
Extravasation Mucocoele
Clinical Features/Aetiology
- Presents as a bluish or transparent swelling
- Most commonly affects minor glands especially in the lower lip
- Occurs over a wide age range but most frequently seen in children and young adults
- Asymptomatic
- May discharge only to re-form
- Typically history of trauma associated with the lesion
- Due to ruptured duct with leakage of saliva into surrounding connective tissue
- Leaked saliva elicits an inflammatory reaction
Mucous Extravasation cyst
Histopathology
- Lesion appears as a cystic cavity filled with mucin in connective
- Mucin is surrounded by inflamed granulation tissue, typically with lots of macrophages
- Not classed as a true cyst as no epithelial lining
Mucous retention cyst (clinical features/aetiology)
- Similar appearance to but less common than extravasation cyst
- Rare on lower lip
- Can affect the major and minor glands
- Represents cystic dilatation of a duct typically due to obstruction
Mucous retention cyst (Histopathology)
- Mucin retained within a dilated duct
- Cyst lining is epithelial lining of the duct
- As saliva is retained within the duct and doesn’t escape, there is much less inflammation
Treatment
- Excision
Ranula
- Painless soft bluish swelling in floor of mouth
Clinical features - Presents as painless soft bluish swelling in floor of mouth
- Unilateral
- 2-3 cm in size
- It is an uncommon form of mucous extravasation cyst arising from sublingual gland
- A ‘plunging ranula’ arises when the mucin passes through and develops below mylohyoid as swelling in neck
Treatment - Drainage of the cystic cavity and removal of sublingual gland
Acute Bacteria Sialadenitis
- The most common causes are bacterial or viral infection
Clinical features - Parotid most often affected
- Decreased salivary flow is major predisposing factor
- Patients present with pain, swelling, tenderness, exudation of pus. There may be redness of overlying skin
- Associated bacteria frequent Staphylococcus aureus, streptococci and oral anaerobes
Treatment - Appropriate antibiotics after culture/sensitivity testing
Chronic Bacterial sialadenitis
Clinical features
- Usually secondary to duct obstruction
- Obstruction most frequently caused by stones/salivary calculi/mucous plugs (parotid)
- Submandibular gland most often affected
- Typically unilateral
- May be asymptomatic or may be intermittent painful swelling which is usually mealtime related
Treatment
- The gland may recover from mild sialadenitis if the associated obstruction can be removed
- If more extensive sialadenitis, the obstruction can be removed
- If more extensive sialenitis, the obstruction and gland requires to be excised
Salivary calculi (Sialoliths/stones)
- Submandibular gland most commonly affected
- Calculi mainly occur in adults
- Caused by mineralisation of phosphates from supersaturated saliva being deposited around a central nidus of cell debris
- Calculi may form within ducts in the gland or in the main excretory duct
- Calculi vary in size, may be more than one, may be round or avoid, rough or smooth and usually yellowish in colour
- Bacteria often grow on the stone surface and elicit an inflammatory response
- No symptoms until stone cause obstruction
- Typically unilateral swelling/pain, often at mealtimes
- Calculi do not cause dry mouth however factors which icnrease saliva saturation e.g. dry mouth, dehydration predisposes to stones
- Treatment varies depending on size and location of stones
- May be possible to remove or breakdown some stones. Alternatively it may be necessary to remove the gland, especially if it has become very damaged by longstanding infection
Mumps (Viral Sialadenitis)
- Acute, contagious infection caused by paramyxovirus
- Spreads via saliva
- Mumps causes painful swelling of parotids and other exocrine glands
- Patients also present with fever headache, malaise
Necrotising Sialometaplasia (Clinical features)
- It is more common in males than females
- More frequently seen in older patients and in smokers
- It mainly affects minor salivary glands, especially those in the hard palate
- Presents as a large, deep ulcer
- May be painful
- Slow to heal, often takes several weeks
Treatment
None required, it slowly resolves itself. Biopsy is usually curative