Inflammation Sialadenitis

Slide 1 · Inflammation (Sialadenitis)

Salivary gland pathology: inflammation, xerostomia, mucocele and ranula

Dr Abu Suraih Sakhri

MBBS, MD (Pathology)

www.abusuraihsakhri.com

Slide 2 · Learning objectives

Identify the salivary-gland sites susceptible to inflammatory disease.

Distinguish traumatic, infectious and autoimmune sialadenitis.

Explain xerostomia, mucoceles and ranulas through gland and duct pathology.

Link microscopic structure to clinical presentation and recurrence.

Slide 3 · Salivary glands at risk

Three paired major glands: Parotid, submandibular and sublingual.

Numerous minor glands occur throughout the upper aerodigestive tract.

Any of these glands may develop inflammatory or neoplastic disease.

Parotid

Submandibular

Sublingual

Major salivary glands

Minor glands: Upper aerodigestive tract

Slide 4 · Glands connect secretory tissue to the mouth

Secretory units form the salivary output.

Ducts conduct secretions toward mucosal openings.

Disruption of the outflow pathway can produce a focal mucus collection.

Acinar secretory unit

Duct → mouth

Schematic

Slide 5 · Two ways salivary function becomes abnormal

Gland inflammation

Triggered by trauma, infection or autoimmunity

May produce gland enlargement

Can accompany a focal mucocele

Reduced saliva secretion

Produces xerostomia

May follow systemic disease, treatment or medication

Causes mucosal and functional complications

Slide 6 · Clinical-pathologic map of this topic

Salivary gland / duct

Inflammation or reduced output

Mucosal or gland lesion

Clinical consequences

The anatomical compartment affected determines whether dryness, gland swelling or a mucus-filled lesion predominates.

Slide 7 · Sialadenitis: Definition and scope

Sialadenitis means inflammation of salivary glands.

Trauma, viral infection, bacterial infection and autoimmune disease as causes.

The presentation depends on which salivary gland and tissue compartment is affected.

Slide 8 · Four principal etiologic pathways

Traumatic

Duct damage

Local mucus leakage

Viral

Mumps

Major gland involvement

Bacterial

Duct-associated infection

Suppurative inflammation

Autoimmune

Sjögren syndrome

Inflammation + dry mouth

Slide 9 · Trauma can injure minor salivary ducts

Minor glands drain through small ducts to the oral mucosa.

Local trauma may rupture a duct.

Escaping saliva accumulates in connective tissue and creates a mucocele.

Minor salivary

Gland

Leakage into stroma

Schematic

Slide 10 · The viral exemplar is mumps

Mumps as the most common viral cause of sialadenitis.

Mumps characteristically affects major salivary glands.

The parotid glands are particularly involved.

Slide 11 · Why the parotid is central in mumps

Parotid involvement is especially characteristic of textbook-described mumps.

Salivary swelling is a local expression of a systemic viral illness.

An inflamed gland should be interpreted in its clinical context.

Parotid

Submandibular

Sublingual

Major salivary glands

Minor glands: Upper aerodigestive tract

Slide 12 · Mumps can involve other glandular organs

Mumps infection

Parotid / major salivary glands

Pancreas or testes may be involved

The pancreas and testes are specifically identified by Robbins as common additional sites of glandular involvement.

Salivary inflammation is not necessarily confined to the mouth.

Slide 13 · Bacterial sialadenitis: Adjacent context

The next Robbins unit discusses bacterial inflammation involving major salivary glands.

Ductal obstruction and reduced secretions can precede bacterial invasion.

Pathology may range from interstitial inflammation to suppurative necrosis and abscess.

Slide 14 · Bacterial inflammation follows impaired drainage

Ductal obstruction / reduced flow

Bacterial invasion

Gland inflammation

Possible suppuration

In adjacent Robbins text, clinical findings include painful unilateral gland enlargement and sometimes purulent ductal discharge.

Slide 15 · Autoimmune sialadenitis in Sjögren syndrome

Sjögren syndrome is the named autoimmune setting in this salivary-gland section.

Reduced salivary output produces xerostomia.

Inflammatory gland enlargement may also be present.

Slide 16 · Sialadenitis may present in different forms

Diffuse gland process

Viral parotid involvement

Autoimmune gland enlargement

Bacterial inflammation of major glands

Focal duct-related lesion

Trauma or duct rupture

Mucus extravasation

Mucocele in surrounding stroma

Slide 17 · Xerostomia means reduced salivary production

Xerostomia is defined here as a dry mouth caused by decreased saliva production.

It may be a manifestation of autoimmune disease, treatment or medication exposure.

Its pathology extends beyond discomfort to mucosal, dental and functional effects.

Slide 18 · Xerostomia is relevant in older adults

That xerostomia may affect as many as 20% of people older than 70 in certain populations.

This is a source-specific, population-dependent estimate, not a universal prevalence.

A thorough medication review is especially relevant account.

Slide 19 · Major causes of xerostomia

Autoimmune

Sjögren syndrome

Sicca symptoms

Treatment

Head and neck radiotherapy

Reduced gland output

Medication

Many prescribed classes

Frequent cause

Slide 20 · Sjögren syndrome links mouth and eye dryness

Salivary component

Decreased salivary secretion

Xerostomia

Sometimes gland enlargement

Lacrimal component

Dry eyes

Keratoconjunctivitis sicca

Paired sicca phenotype

Slide 21 · Radiotherapy can damage salivary output

Head / neck irradiation

Impaired salivary secretion

Dry oral mucosa

Xerostomia-related sequelae

Reduced saliva as a major complication of radiation therapy for head and neck cancer.

Slide 22 · Medications are a major cause of dry mouth

Drug effects as the most frequent source of xerostomia.

The implicated prescriptions belong to several distinct therapeutic classes.

Do not restrict the history to drugs specifically marketed as anticholinergics.

Slide 23 · Medication classes: Autonomic and psychotropic

Autonomic effects

Anticholinergic medications

Antihypertensives

Diuretics

Central nervous system agents

Antidepressants

Antipsychotics

Sedatives

Slide 24 · Medication classes: Additional examples

Symptom control

Analgesics

Muscle relaxants

Allergy medications

Antihistamines

Assess concurrent use with other causes

Slide 25 · Xerostomia: Visible examination findings

Dryness of the oral mucosa is a direct clinical sign.

Atrophy of the tongue papillae may be seen.

Mucosal fissuring and ulceration may accompany prolonged dryness.

Slide 26 · Tongue papillary atrophy is a surface change

Reduced saliva

Loss of normal moist surface

Atrophic lingual papillae

The tongue finding provides an examinable correlate of a reduced salivary state; It is not specific for a single cause.

Slide 27 · Fissures and ulcers mark mucosal injury

Dry oral mucosa

Surface fissuring

Possible ulceration

Recognize fissures and ulcers as consequences in the xerostomia description, not as separate primary salivary lesions.

Slide 28 · Dental caries is a major consequence

Inadequate saliva is associated with increased dental caries.

Saliva normally contributes to a protective oral environment.

Oral findings should prompt consideration of a salivary cause.

Slide 29 · Candidiasis may accompany reduced saliva

Reduced secretions

Altered mucosal protection

Higher risk of oral candidiasis

Candidiasis is listed among complications of xerostomia.

Slide 30 · Swallowing and speaking may be impaired

Swallowing

Saliva helps oral food handling

Dry mouth creates difficulty swallowing

Speech

Moist mucosa facilitates oral articulation

Dryness may interfere with speaking

Slide 31 · Xerostomia has a connected complication chain

Decreased saliva

Oral dryness / surface injury

Caries or candidiasis

Swallowing / speech difficulty

These outcomes coexist but are not a compulsory stepwise sequence in every patient.

Slide 32 · Assess the cause of oral dryness systematically

Clinical clue

Source-grounded association

Dry eyes + dry mouth

Sjögren syndrome

Head and neck irradiation

Treatment-related salivary damage

Relevant medication use

Drug-associated xerostomia

Dry tongue, fissures, caries

Consequences of low secretion

Slide 33 · Mucocele: A focal saliva-related lesion

A mucocele is a common manifestation in the sialadenitis section.

It arises from obstruction or rupture of a salivary duct, with subsequent salivary leakage into surrounding connective tissue.

Minor glands of the lower lip are a particularly characteristic site.

Slide 34 · Lower-lip trauma is a frequent setting

Most mucoceles on the lower lip.

They commonly follow local trauma.

The lesion can occur at any age.

Fluctuant lesion

Simplified lower-lip schematic

Slide 35 · Mucocele begins with duct injury

Minor salivary glands lie just beneath oral mucosal surfaces.

Trauma can damage their ductal pathway.

Escaping secretion dissects into surrounding connective tissue.

Minor salivary

Gland

Leakage into stroma

Schematic

Slide 36 · Duct rupture explains mucus extravasation

Local trauma

Minor duct rupture

Mucin escapes to stroma

Reactive cystlike cavity

Extravasated saliva is outside a normal epithelial duct lumen.

Slide 37 · Duct obstruction is another described trigger

Ductal blockage as another initiating event.

Interference with drainage promotes mucus accumulation.

The source then describes a stromal, pseudocystic lesion.

Minor salivary

Gland

Impaired duct flow

Schematic

Slide 38 · The mucocele cavity is not a true cyst

The classic histologic lesion is a mucus-filled pseudocyst.

Its boundary is formed by granulation tissue or fibrous connective tissue.

A continuous epithelial cyst lining is not present in this model.

Slide 39 · Pseudocyst architecture: Low-power reasoning

A cavity occupies connective tissue adjacent to a minor gland.

Mucinous contents occupy the central space.

A reactive connective tissue wall encircles the collection.

Mucin-filled cavity

Minor gland

Schematic, not histology

Slide 40 · Granulation tissue forms a reactive boundary

Salivary leakage

Local inflammatory reaction

Organizing granulation tissue

Fibrous wall with time

The diagnostic wall is reactive tissue rather than a salivary-duct epithelial lining.

Slide 41 · Mucin forms the characteristic luminal material

The cavity contains mucinous secretions.

Mucin is located outside its normal duct compartment.

Extravasated material triggers a surrounding tissue response.

Mucin-filled cavity

Minor gland

Schematic, not histology

Slide 42 · Macrophages participate in mucocele lesions

Inflammatory cells occur within the mucus-filled cavity.

Macrophages are highlighted specifically in the Robbins description.

Their presence reflects the response to extravasated material.

Slide 43 · The adjacent gland is a diagnostic clue

An intact minor salivary-gland lobule may lie beside the cavity.

The spatial relationship supports a salivary duct origin.

Robbins’ referenced figure includes an adjacent intact gland.

Mucin-filled cavity

Minor gland

Schematic, not histology

Slide 44 · Histologic checklist for an extravasation mucocele

Component

What to recognize

Cavity

Mucinous material

Cavity wall

Granulation / fibrous connective tissue

Inflammatory population

Macrophages and other inflammatory cells

Nearby structure

Minor salivary-gland lobule

Slide 45 · Fluctuance reflects a fluid-filled cavity

Collected saliva / mucin

Compliant soft-tissue cavity

Fluctuant swelling

The lesion may be described as a cystlike swelling on physical examination.

Slide 46 · Blue translucency is a characteristic clue

The lower-lip lesion often has a blue translucent hue.

Its appearance is consistent with an underlying fluid-filled collection.

Color alone is not a substitute for clinicopathologic assessment.

Fluctuant lesion

Simplified lower-lip schematic

Slide 47 · Mucocele size may fluctuate with meals

Patients may describe changes in lesion size.

The history may show a temporal association with eating.

The variation provides a clue to a lesion connected with salivary flow.

Slide 48 · Clinical and microscopic findings are concordant

Clinical observation

Trauma-associated lower-lip swelling

Fluctuant, often blue-translucent

Variable size, sometimes around meals

Microscopic correlate

Mucus-containing cavity

Reactive connective tissue wall

Mucin with inflammatory cells / macrophages

Slide 49 · Excision must address the source gland

Mucocele cavity

Associated minor gland lobule

Complete excision

Lower recurrence risk

Robbins specifically advises removing the accompanying gland lobule when excising a mucocele.

Slide 50 · Incomplete excision permits recurrence

Incomplete removal

Residual associated lobule may remain

Ongoing secretion may reform a lesion

Recurrence is possible

Complete removal

Cystlike lesion excised

Accompanying minor gland lobule included

Addresses the local source of saliva

Slide 51 · Ranula is a named sublingual-duct lesion

Robbins reserves the term ranula for an epithelial-lined cyst after damage to a sublingual gland duct.

The anatomical origin is the sublingual gland and its outflow pathway.

This wording is source-specific and should not be generalized to every ranula mechanism.

Slide 52 · The floor of mouth defines ranula anatomy

Sublingual glands occupy the floor-of-mouth region.

A damaged sublingual duct can produce a cystic swelling.

An expanding lesion may follow connected tissue spaces.

Floor of mouth / sublingual compartment

Mylohyoid muscle plane

Extension through connecting tissue

Schematic; Not an anatomical cross-section

Slide 53 · Plunging ranula: Extension beyond the mouth

Sublingual-duct lesion

Expansion through connective tissue

Extension beside mylohyoid bellies

Plunging ranula

The “plunging” descriptor refers to anatomical extension, not a separate named infection.

Slide 54 · Mylohyoid relationships explain the extension

The mylohyoid forms a muscular plane in the floor of the mouth.

A cyst dissecting through stroma between its two bellies.

This allows a ranula to extend beyond its original space.

Floor of mouth / sublingual compartment

Mylohyoid muscle plane

Extension through connecting tissue

Schematic; Not an anatomical cross-section

Slide 55 · Mucocele and ranula: Source-level contrast

Feature

Typical mucocele

Ranula

Common origin

Lower-lip minor gland

Sublingual duct

Trigger

Trauma / duct blockage or rupture

Duct damage

Microscopic wall

Pseudocyst; Reactive tissue

Described as epithelial-lined

Characteristic extension

Local stromal mucus pool

May become “plunging”

Slide 56 · Do not collapse all salivary lesions together

Process

Main feature

Pathologic logic

Sialadenitis

Gland inflammation

Trauma, infection, autoimmunity

Xerostomia

Low salivary output

Systemic, treatment or medication association

Mucocele

Local mucus-filled lesion

Damaged or obstructed duct

Ranula

Sublingual-related cyst

May extend through floor of mouth

Slide 57 · Case 1: Lower-lip swelling

A patient has a fluctuant, blue-translucent nodule of the lower lip after local trauma. Its size changes around mealtimes.

What lesion is suggested, and what microscopic wall is expected?

Slide 58 · Case 1: Correlate the two observations

Likely lesion

Mucocele of a minor gland

Trauma-associated duct injury

Salivary extravasation into stroma

Expected morphology

Mucin-filled pseudocyst

Granulation / fibrous wall

Macrophages, without an epithelial lining

Slide 59 · Case 2: Dryness with other findings

An older patient reports oral dryness, has an atrophic tongue and dental caries, and takes several prescribed medications.

Which pathophysiologic process best links these findings?

Slide 60 · Case 2: Identify reduced saliva secretion

Diagnosis to consider

Xerostomia from decreased production

Review medications as a major cause

Also consider autoimmune and treatment history

Clinical consequences

Dry mucosa and papillary atrophy

Increased caries / candidiasis

Speech or swallowing difficulty

Slide 61 · Case 3: Major-gland inflammation

A patient with an acute viral illness has prominent parotid swelling, and the clinical context raises concern for involvement of other glandular organs.

Which source-named infection is the archetype?

Slide 62 · Case 3: Identify the glandular distribution

Expected association

Mumps

Particularly affects parotid glands

Other major glands may be involved

Systemic implication

Pancreatic involvement may occur

Testicular involvement may occur

Interpret gland swelling within whole-patient illness

Slide 63 · Diagnostic synthesis: Start with the phenotype

Dryness → xerostomia

Diffuse gland inflammation → sialadenitis

Lower-lip cystlike nodule → mucocele

Sublingual/floor-of-mouth cyst → ranula

This is a teaching classification of dominant phenotypes; It is not a validated clinical diagnostic algorithm.

Slide 64 · Four pathology points to retain

Sialadenitis arises from trauma, infection or autoimmune disease.

Xerostomia can reflect Sjögren syndrome, radiotherapy or medications and has substantial oral consequences.

Mucocele is characteristically a lower-lip mucus-containing pseudocyst.

Ranula originates in the sublingual region and may extend through the mylohyoid connective tissue.

Slide 65 · Primary reference and source boundaries

Robbins, Cotran & Kumar: Pathologic Basis of Disease, 11th edition (2026).

Chapter 16, Head and Neck; salivary glands and related inflammatory lesions, printed pages 678–679.

Details of sialolithiasis and suppurative bacterial sialadenitis are reserved for the adjacent independent unit.

Native diagrams in this lecture are schematics, not actual clinical or histologic specimens.