6. Benign white and red patches of the oral mucosa Flashcards
What are fordyce spots?
Choristoma
Sebaceous glands
Found in upper lip and cheeks
What are Koplik’s spots?
Found in oral mucosa when someone has measles.
Disappear when skin rash occurs
White/blue
Range from few to hundreds
What is the chemical formula of aspirin?
C9H8O4
What is an aspirin burn caused by?
Aspirin is a cyclooxygenase inhibitor.
The chemical injury is caused by acetylsalicyclic acid.
What is Reye’s syndrome?
Increase in pressure of the brain and other organs.
It is linked to taking aspirin in young people.
DO not give aspirin to people under 16.
What is simple keratosis?
Increase in thickness of the keratinised layer of the epithelium.
Cannot be removed by scrapping.
What is simple keratosis caused by?
Irritation such as trauma, smoking, bad hygiene
What is speckled leukoplakia called?
Erythroplakia- red and white. This is premalignant.
What is the cause of white sponge naevus?
Autosomal dominant condition
Affects 1 in 200000
Due to mutations in genes coding for keratin 4 and 13
What does white sponge naevus look like?
Painless white patches appear at young age in cheeks, ventral tongue, floor of mouth.
What is the histology of white sponge naevus?
Acanthotic epithelium and parakeratosis
Intracellular oedema
Pyknotic nuclei
Basket weave appearance in epithelium
Perinuclear eosinophilic condensations
Basal layer intact, no inflammation
Some abnormality in the desquamation process
What is the aetiology of lichen planus?
Altered expression of keratinocytes
Instead of class 1, they express class 2 histocompatibility antigens which transforms them into antigen presenting cells. The keratinocytes start presenting themselves as antigens to T cells, which generates an immune response by cytotoxic cells against the epithelium.
What is the oral appearance of lichen planus?
white, Wickhan’s striae present in buccal mucosa and other sites but uncommon on floor of mouth
Cannot be removed by a gauze
What is the histology of Lichen planus?
Parakeratosis
Irregular acanthosis- triangular saw tooth rete ridges
Liquefaction or degeneration of the basal cell layer
Band like lympho-histiocytic infiltrate under the epithelium- lymphocytes and histocytes, not plasma cells or neutrophils
Presence of civatte (hyaline) bodies- apoptotic features
What are the 6 different types of lichen planus?
Erosive- extensive areas with ulceration
Plaque like- white patches
Reticular- lace like
Bullous- sup-epithelial bullae
Papular- small white papules
Atrophic- diffuse red lesions- erythroplakia
What are the 2 forms of lupus erythematous?
Chronic discoid LE- mostly on skin, sometimes on face forming butterfly pattern
Systemic LE- disseminated disease
What is the aetiology of LE?
Immunological/genetic hypersensitivity of B lymphocytes
Which LE has oral lesions?
Chronic discoid LE
Erythematous patches with white keratotic borders, can have radiating striae
Histology of LE?
Hyperplastic epithelium
Subepithelial and deep perivascular lymphocytic infiltration
Liquefaction of basal cells
IgG and C in basement membrane zone
Keratin plugging- keratin is not just present at the surface of the epithelium but goes down into the rete pegs
What happens to the fingers in Raynaud’s phenomenon?
Intermittent vasospasms- white to blue to red
Vasoconstriction makes white, then they get hypoxic white makes them blue, then they vasodilate again to make them red.
What is the cause of Raynaud? What diseases is it seen a lot in?
Idiopathic
Secondary to connective tissue disorders
Lupus, Sjogren, rheumatoid arthritis, scleroderma
What are systemic origins of red patches?
Haematological diseases
Infectious diseases
Vascular proliferative conditions
Polycythaemia
What are local origins of red patches?
Haemangioma
Geographic glossitis
Median rhomboid glossitis
Ulcers
What is polycythaemia?
Increase in RBC in the blood
What are the 2 types of polycytheaemia?
Relative- same number of RBC, but volume of blood reduced
Absolute- overproduction of RBC
What are the 2 types of absolute polycythaemia?
Vera- serious
Secondary- In response of stimulus, eg. less oxygen in high altitude environments
What can anaemia be due to?
Decrease in amount of blood
Decrease in iron
Defective cells
Increase in haemolysis
Decrease in haemopoiesis
What does pernicious anaemia cause?
Hunter’s glossitis- beefy tongue
What is aplastic anaemia?
Body stops producing enough new red blood cells.
Platelets will be very deficient so they will have areas of haemorrhage in the soft tissue.
What is a haemangioma?
Hamartoma- red patches associated with localised proliferation of capillary and cavernous blood vessels.
What is a vitropressure test?
Press the lesion to see if it goes white, then see if it goes red again.
What do you do instead of biopsy for lesions that bleed a lot?
Freeze it
Try and produce artificial embolism, eg. polystyrene pellet
Use electric scalpel that coagulates as you cut around or ligate the artery
What is median rhomboid glossitis?
Lesions present in the midline of dorsal tongue
Candidal hyphae present in many cases- candidosis
Some may have candidal hyphae present in opposite side of the palate
What is the histology of median rhomboid glossitis?
Lack of filliform papillae
Parakeratinised
Acanthotic epithelium
Neutrophil infiltration
Superficial microabscess formation
