5. Pathogenesis
1. Retrograde contamination of the salivary ducts
and parenchymal tissues by bacteria inhabiting
the oral cavity.
2. Stasis of salivary flow through the ducts and
parenchyma promotes acute suppurative
infection.
5
6. Acute Suppurative
More common in parotid gland.
The etiologic factor most associated with this
entity is the retrograde infection from the
mouth.
6
7. Predilection for Parotid
Salivary Composition
The composition of parotid secretions
differs from those in other major glands.
Parotid is primarily serous, the others have a
greater proportion of mucinous material.
7
8. Salivary Composition
Mucoid saliva contains elements that protect against
bacterial infection including lysozymes & IgA
antibodies (therefore, parotid has bacteriostatic activity)
Mucins contain sialic acid which agglutinates bacteria
and prevents its adherence to host tissue.
Specific glycoproteins in mucins bind epithelial cells
competitively inhibiting bacterial attachment to these
cells.
8
9. Parotid Predilection
Anatomic factors
Stensen’s duct lies adjacent to the maxillary
molars and Wharton’s near the tongue.
It is thought that the mobility of the tongue may
prevent salivary stasis in the area of Wharton's that
may reduce the rate of infections in SMG.
9
11. Risk Factors continued…
Neoplasms (pressure occlusion of duct)
Sialectasis (salivary duct dilation) increases the risk for
retrograde contamination. Is associated with cystic
fibrosis and pneumoparotitis
Extremes of age
Poor oral hygiene
Calculi
11
12. Acute Suppurative Parotitis
Sudden onset of erythematous swelling of the
pre/post auricular areas extend into the angle
of the mandible.
Is bilateral in 20%.
12
13. Bacteriology
Purulent saliva should be sent for culture.
Staphylococcus aureus is most common
Streptococcus pnemoniae and S.pyogenes
Haemophilus Influenzae also common
13
14. Treatment of Acute Sialadenitis
Reverse the medical condition that may have
contributed to formation
Warm compresses, give sialogogues (lemon
drops)
External salivary gland massage if tolerated
14
15. Treatment of Acute
Sialadenitis/Parotitis
Antibiotics!
70% of organisms produce B-lactamase or
penicillinase
Need B-lactamase inhibitor like Augmentin or
Unasyn or second generation cephalosporin
Can also consider adding metronidazole or
clindamycin to broaden coverage
15
16. Surgery for Acute Parotitis
When a discrete abscess is identified, surgical
drainage is undertaken
Approach is anteriorly based facial flap with
multiple superficial radial incisions created in the
parotid fascia parallel to the facial nerve
Close over a drain
16
17. Complications of Acute Parotitis
Direct extension
Abscess ruptures into external auditory canal and
TMJ have been reported
Hematogenous spread
Thrombophlebitis of the retromandibular or
facial veins are rare complications
17
18. Complications
Extension of an abscess into the parapharyngeal space
may result in airway obstruction, mediastinitis, internal
jugular thrombosis and carotid artery erosion
Dysfunction of one or more branches of the facial
nerve is rare.
18
19. Chronic Sialadenitis
Causative event is thought to be a lowered
secretion rate with subsequent salivary stasis.
More common in parotid gland.
Damage from bouts of acute sialadenitis over
time leads to progressive acinar destruction
combined with a lymphocyte infiltrate.
19
21. No treatable cause found:
Initial management should be conservative and
includes the use of sialogogues, massage and
antibiotics for acute exacerbations.
Should conservative measures fail, consider
removing the gland.
21
22. Acute viral infection (AVI)
Mumps classically designates a viral parotitis
caused by the paramyxovirus
However, a broad range of viral pathogens have
been identified as causes of AVI of the salivary
glands.
22
23. Viral infection
Mumps is a non-suppurative acute sialadenitis
Is endemic in the community and spread by
airborne droplets
Communicable disease
Enters through upper respiratory tract
23
24. Mumps
2-3 week incubation after exposure (the virus
multiplies in the upper respiratory tract or
parotid gland)
Then localizes to biologically active tissues like
salivary glands, germinal tissues and the CNS.
24
25. Virology
Caused by paramyxovirus, an RNA virus
Others can cause acute viral parotitis:
Coxsackie A & B virus, cytomegalovirus and
adenovirus
HIV involvement of parotid glands is a rare
cause of acute viral parotitis
25
26. Clinical presentation
30% experience prodromal symptoms prior to
development of parotitis
Headache, anorexia, malaise
Onset of salivary gland involvement is
preceeded by earache, gland pain, dysphagia and
trismus
26
27. Physical exam
Glandular swelling (tense, firm) Parotid gland
involved frequently, SMG & SLG can also be
affected.
May displace pinna
75% cases involve bilateral parotids, may not
begin bilaterally (within 1-5 days may become
bilateral)….25% unilateral
Low grade fever
27
29. Complications
Orchitis, testicular atrophy and sterility in
approximately 20% of young men
Oophoritis in 5% females
Aseptic meningitis in 10%
Pancreatitis in 5%
Hearing loss <5%
Usually permanent
80% cases are unilateral
29
30. Immunologic Disease
Sjögren’s Syndrome
Most common immunologic disorder
associated with salivary gland disease.
Characterized by a lymphocyte-mediated
destruction of the exocrine glands leading to
xerostomia and keratoconjunctivitis sicca
30
31. Sjögren’s syndrome
90% cases occur in women
Average age of onset is 50y
Published in 1933 by Sjögren, a Swedish
ophthalmologist
31
32. Sjögren’s Syndrome
Two forms:
Primary: involves the exocrine glands only
Secondary: associated with a definable
autoimmune disease, usually rheumatoid
arthritis.
80% of primary and 30-40% of secondary involves
unilateral or bilateral salivary glands swelling
32
34. Sjögren’s Syndrome
Keratoconjuntivitis sicca: diminished tear production
caused by lymphocytic cell replacement of the lacrimal
gland parenchyma.
Evaluate with Schirmer test. Two 5 x 35mm strips of
red litmus paper placed in inferior fornix, left for 5
minutes. A positive finiding is lacrimation of 5mm or
less. Approximately 85% specific & sensitive
34
36. Sjögren’s Lip Biopsy
Single 1.5 to 2cm horizantal incision labial mucosa.
Not in midline, fewer glands there.
Include 5+ glands for identification
Glands assessed quantitatively to determine the
number of foci of lymphocytes per 4mm2/gland
36
38. Sialadenosis
Non-specific term used to describe a noninflammatory non-neoplastic enlargement of a
salivary gland, usually the parotid.
May be called sialosis
The enlargement is generally asymptomatic
Mechanism is unknown in many cases.
38
39. Related to…
a.
b.
Metabolic “endocrine sialendosis”
Nutritional “nutritional mumps”
a.
b.
c.
Obesity: secondary to fatty hypertrophy
Malnutrition: acinar hypertrhophy
Any condition that interferes with the absorption
of nutrients (uremia, chronic pancreatitis)
39
41. Radiation Injury
Low dose radiation to a salivary gland causes an
acute tender and painful swelling within 24hrs.
Serous cells are especially sensitive and exhibit
marked degranulation and disruption.
41
42.
Continued irradiation leads to complete
destruction of the serous acini and subsequent
atrophy of the gland.
Similar to the thyroid, salivary neoplasm are
increased in incidence after radiation exposure.
42
43. Granulomatous Disease
Primary Tuberculosis of the salivary glands:
Uncommon, usually unilateral, parotid most
common affected
Believed to arise from spread of a focus of infection
in tonsils
Secondary TB may also involve the salivary
glands but tends to involve the SMG and is
associated with active pulmonary TB.
43
44. Granulomatous Disease
Sarcoidosis: a systemic disease characterized by
noncaseating granulomas in multiple organ systems
Clinically, SG involvement in 6% cases
44
45. Cysts
True cysts of the parotid account for 2-5% of
all parotid lesions
May be acquired or congenital
Branchial arch cysts are a duplication anomaly
of the membranous external auditory canal
45
48. Salivary Gland Neoplasms
Diverse histopathology
Relatively uncommon
2% of head and neck neoplasms
Distribution
Parotid: 80% overall; 80% benign
Submandibular: 15% overall; 50% benign
Sublingual/Minor: 5% overall; 40% benign
48
49. Pleomorphic Adenoma
Most common of all salivary gland neoplasms
70% of parotid tumors
50% of submandibular tumors
45% of minor salivary gland tumors
6% of sublingual tumors
4th-6th decades
F:M = 3-4:1
49
66. Monomorphic Adenomas
Basal cell is most common: 1.8% of benign
epithelial salivary gland neoplasms
6th decade
M:F = approximately 1:1
Caucasian > African American
Most common in parotid
66
67. Basal Cell Adenoma
1- Solid
Most common
Solid nests of tumor
cells
Uniform,
hyperchromatic, round
nuclei, indistinct
cytoplasm
Peripheral nuclear
palisading
67
81. Mucoepidermoid Carcinoma
Treatment
Influenced by site, stage, grade
Stage I & II
Wide local excision
Stage III & IV
Radical excision
+/- neck dissection
+/- postoperative radiation therapy
81
82. Adenoid Cystic Carcinoma
Overall 2nd most common malignancy
Most common in submandibular, sublingual
and minor salivary glands
M=F
5th decade
Presentation
Asymptomatic enlarging mass
Pain, paresthesias, facial weakness/paralysis
82