Category:Oral Cavity - Vesicular Pathology

Pathology

• Damage to prickle cells (stratum spinosum).
• Appears as accumulation of fluid within epithelium, quickly erodes leaving hyperaemic stratum germinativum.
• Heals by proliferation of new cells, so long as infection does not continue.

Pathogenesis

May be caused by:

1. Ingestion of hot food (corrosive liquids)
2. Systemic viral diseases. e.g:
   1. Foot and Mouth disease - ruminants and pigs
   2. Vesicular stomatitis - horse, pigs, cattle
   3. Vesicular exanthema - pigs

N.B. All are indistinguishable from FMD clinically.

Foot and Mouth Disease (FMDV)

Pathology

Gross

1. Initially - hyperaemia of mucosa (e.g. catarrhal inflammation) then within 12 hours produces fluid filled vesicles on dorsum of tongue, may be other places
2. Small vesicle coalesce to produce big ones -i.e. Bullae
3. Very quickly rupture; epithelium appears dirty grey in colour because of necrosis - sloughed skin, very good for diagnosis
4. Leave painful, hyperaemic epithelium
5. Looks like "ulcer "with ragged edge but not a true ulcer as stratum germinativum retained and will rapidly heal completely in about 2 weeks unless becomes secondarily infected

Microscopic lesions

• Degeneration of prickle cells
• Cells "balloon" as fill with fluid and then die to produce vesicle containing straw coloured or clear fluid

Swine Vesicular Disease

• May produce vesicles in mouth that are indistinguishable from foot and mouth disease
• Swine vesicular disease produces sporadic large outbreaks
  • Approximately 5% have lesions in mouth, foot lesions much more common

Vesicles in dogs

• Vesicles in mouth are often caused by hot food - especially in dogs.
• Can produce quite big vesicles, but will heal.
• No major problems associated with vesicles on tongue in dogs (except if due to drinking battery acid, but this also produces vomiting).