OM - Lichen Planus Flashcards
Whos at risk of lichen planus?
30-50 year olds
What causes lichen planus? (8)
- Idiopathic cause
- Genetic predisposition – Not specifically HLA linked
- Physical and emotional stress
- Injury to the skin; lichen planus often appears where the skin has been scratched or after surgery (in susceptible patients)
- Localized skin disease such as herpes zoster
- Systemic viral infection, such as hepatitis C
- Contact allergy – to metal fillings (amalgam)
- Drugs – esp antihypertensives and Gold, Quinine
what is an isomorphic response (koebnerisation) in relation to LP?
where injury to the skin can cause lichen planus to appears (where the skin has been scratched or after surgery) in susceptible patients
Describe the histological appearance/characteristics of lichen planus. (5)
T cell infiltrate into the basement membrane area of CT = Lymphocytic band hugging the membrane (key diagnostic feature_
- Chronic Inflammatory cell infiltrate
- Saw tooth rete ridges
- Basal cell damage
- Patchy acanthosis
- Parakeratosis
What does the histological appearance tell us about what occurs in lichen planus?
Lymphocytes are attracted to the area specifically to deal with a perceived threat – Langerhans cells in the epithelium present an antigen which activates an immune response.
The immune response attempts to remove the chronic irritation which causes the changes in the epithelium and the clinical appearance.
What are some of the types of LP? Describe (3)
- Reticular – lacey pattern on;
Normal mucosa Or Erythematous mucosa - Atrophic – where erythema (=atrophy) is the predominant feature
Erosive = where atrophy results in no epithelial cover - Ulcerative = where atrophy results in no epithelial cover
What are the symptoms of oral LP? (3)
- Often none
- Sensitive to hot/spicy food & Burning sensation in the mucosa
- from thinning of the epithelium
- Up to 50% patients have other areas of the body involved
- Skin
- Scalp
- Genitals
- hair
- nails
Where else can LP present? (4)
Cutaneous - skin
Wrists:
- raised purple lesions with white striae (Wickems striae)
Scalp – area of hair loss were lesions present
Nails – characteristic ridging
Describe the sites where oral LP is commonly found. (5)
- Buccal mucosa – most common site
- Gingivae (Desquamative Gingivitis – when in isolation)
- Tongue – lateral aspect, dorsum
- Lips
- Palate
Where is the most common site for oral LP?
Buccal mucosa
Where on the buccal mucosa can LP present? (3)
- Anterior at commissure
- Mid
- Posterior around 3rd molar tooth
where is the most common site for incidental/asymptomatic finding of LP?
Buccal mucosa
How do we differentiate between desquamative gingivitis and pemphigoid and plasma cell gingivitis?
Biopsy - histological examination
What are the characteristics of gingival LP/desqamative gingivitis? (3)
- patchy appearance
- mostly erythematous however Some forms give a more ‘typical’ reticular lichenoid pattern
- lesions can be found in isolation
What can gingival LP also be known as when the lesions only affect the gingival tissues?
Desquamative gingivitis
How do we manage gingival LP? (1)
Ensure there is plaque control as these lesions seem to be plaque driven (esp interdental plaque)
What are the risks of gingival biopsy (1) and what techniques help us to reduce these? (2)
– Risk of damaging the attachment/junctional area of the gingiva/tooth
– Must have a good clear margin between tooth and the lesion
– Ideally sample from high in the sulcus
What are the characteristics of LP on the dorsum of the tongue? (1)
Lesions on the dorsum = loss of papillae and smooth tongue surface
What commonly causes lichen planus on the dorsum of the tongue?
idiopathic
what usually causes lichen planus on the lateral aspect of the tongue? (2)
may have drug/amalgam trigger
- Amalgam most likely if there is an ISOLATED lateral tongue lesion
- Look at tongue position at REST to see if there is amalgam contact
What are the general characteristics of lichen planus? (3)
- More often WIDESPREAD lesions
- Often BILATERAL and mirrored
- Often poorly responsive to
standard steroid treatment
How do we describe an oral lichenoid lesion where the cause is know?
‘lichenoid reaction to..”
What medications are associated with lichen planus? (5)
(antihypertensives)
- b-adrenergic blockers
- ace inhibitors
- diuretics: Bendroflumethiazide, frusemide
- NSAIDS
- DMARDS (disease modifying antirheumatic drugs e.g. sulphasalazine)
- Phenothiazines (rare)
How do we manage lichenoid drug reactions? (3)
consider/assess;
Benefit of drug causing the reaction - Does the benefit of stopping the medical drug outweigh the risk to the patient’s health
Mild lichen symptoms – unlikely, Significant lichen symptoms – yes probably (Where maximum topical or systemic treatment likely needed to control the lichen symptoms)
If in doubt, discuss with the GP - Maybe medicine no longer needed or there is an easy change to an alternative
- Risk of stopping drug
- Discomfort from symptoms
What is the suggested cause of amalgam causing lichenoid reactions?
not entirely sure
Old amalgams
possibly the corrosion products of amalgams
How do we manage amalgam related lesions? (2)
No symptomatic = do nothing
(however, low risk that it could be a potentially malignant lesion)
symptoms = replace
What are the problems associated with not treating an amalgam that is causing a lichenoid reaction?
very low risk that it Could be a potentially malignant lesion
What are the problems associated with replacing an amalgam that is causing a lichenoid reaction? (2)
- Replacing restoration will increase tooth damage
- Cost to patient for amalgam removal
If one amalgam is causing a lichenoid reaction should all other amalgams be replaced?
No routine need – reactions seem to be some caused by the change in the amalgam involved e.g. corrosion – the change is the only problematic amalgam.
Only replaced when in direct contact with the lichenoid lesions
When should we completely avoid replacing amalgams causing ARL’s?
pregnancy
What restorative tx should we avoid in a px with a history of lichenoid reactions and why? (1)
Avoid bonded crowns as palladium can be associated with Lichenoid reactions however the incidence is much lower
What are the general management strategies for lichen planus? (3)
- Remove any cause:
- Medicines
- Dental restorations - BIOPSY
- Unless a good reason not to e.g. lichenoid, RAU - Blood tests
LP more symptomatic in px with haematinic deficiency
- Haematinincs
- FBC
Why is a blood test relevant when diagnosing LP?
LP more symptomatic in px with haematinic deficiency
How do we manage intermittent lichen planus? (2)
- Topical OTC remedies
- Chlorhexidene m/w
- Benzdamine m/w
- All patients to avoid SLS containing toothpaste (esp in gingival lesions)
- Sensodyne Pronamel
- Kingfisher
How do we manage persistent lichen planus in the primary setting? (1)
- Topical steroids (as for Oral Ulcers)
- Beclomethasone MDI 0.5mg/puff – 2 puffs x 2-3 daily
- Betamethasone rinse – 1mg/10ml/2mins/twice daily
Advise that during the lesion/symptom free period to stop using the drugs and then start using again once the lesions/symptoms appear
How do we manage persistent lichen planus in a Hospital setting if primary care efforts are unsuccessful? (4)
- Higher strength topical steroids
– puffer or rinse - ‘Skin’ Steroid Cream – CLOBETASOL in a ‘veneer’ for gingival lesions
- Topical tacrolimus – ointment or mouthwash
- Hydroxychloroquine – cutaneous and oral LP
- Systemic immunmodulators
- Azathioprine
- mycophenolate
provide 2 examples of systemic immunomodulators.
- Azathioprine
- mycophenolate
What causes GVHD? (2)
Bone marrow/stem cell transplant
Describe what graft vs host disease is sing an example.
after a bone marrow transplant/ Stem cell transplant, the patient’s new bone marrow recognises a foreign host and is causing immunological damage to the mouth in order to reject the host = appearance of lichen like lesions
Describe how GVHD presents in the mouth, how do we differentiate between this and lichen planus?
Lichen like lesion
- appears in unusual LP positions such as the hard palate
Describe how GVHD appears histologically
Similar to LP
- has a lymphocytic band along the basement membrane and a change in the keratinized/prickle cell layers.
What diseases can present in a similar manner to Lichen planus in the mouth? (2)
GVHD - graft vs host disease
Lupus (various types)
For what lesions must we always consider lupus erythematosus in our differential diagnosis?
palatal lichen like lesions
How can discoid lupus present in the mouth?
What other tests can be used to confirm this diagnosis?
Lichen like lesions that ONLY present in the mouth
- no auto antibodies present on a blood test.
How can systemic lupus present in the mouth?
What other tests can be used to confirm this diagnosis?
lichen like lesions present in the mouth and elsewhere
– autoantibodies ANA/Ro/dsDNA present in the blood sample
What autoantibodies are present in systemic lupus (3)
anti-ANA
anti-Ro
anti-dsDNA
Describe how lupus appears histologically.
Different appearance to lichen planus as the lymphocyte infiltration is much deeper in the connective tissue and away from the basement membrane
How do we treat only oral lichen like (GVHD&Lupus) symptoms? (2)
- Treat symptoms as Lichen Planus
- Liaise with physician regarding oral lesions
