Dermatology II Flashcards
1. To recognise the signs and symptoms of common dermatological conditions 2. Outline typical presentations on the face and lips and visible parts of the skin in dental patients 3. Explain the dental relevance of dermatological disease
What mucocutaneous lesions can occur with lichen planus
- Lichen planus
- Lichenoid reaction (due to underlying hypersensitivity)
- Discoid lupus erythematosus (develops into SLE)
What is lichen planus
A common disorder with widespread presentation (oral, genital and cutaneous) which is immunologically mediated (autoimmune) - this is a premalignant condition
Outline the difference between oral and skin lesions go lichen planus
Oral lesions are chronic: 4-25 years
Skin lesions are active for ~ 18 months
These may be present concurrently or at different times
Outline the oral presentation of lichen planus
- Reticular (white lines)
- Erythematous (atrophic) - thin and red mucosa
- Erosive (ulcerative) - keratotic presentation is more common
- Symmetrical presentation (for skin and mouth)
- Several at once
What are the common sites for lichen planus in the mouth
Buccal/ Labial mucosa, tongue and gingiva -
rarely on palate, lingual aspect
Why does lichen planus occur in specific areas of the mouth
Because it occurs in areas of increased friction e.g. occlusal line due to the Koebner phenomenon
What are the morphological variants in lichen planus
Papular, reticular, plaque-like, atrophic, erosive (ulcerative), bullous (blistering type associated with pemphigus)
Describe the extra-oral presentation of lichen planus
- Cutaneous
- Purple polygonal pruritic papules
- Dystrophic nails
- Genital involvement
- Lichen planopilaris leading to scarring alopecia (irreversible hair loss)
- Sites include: ocular, nasal, laryngeal, oesophageal, gastric, bladder
Outline the common presentation of cutaneous lichen planus
Mainly flexor surfaces of wrists and shins with symmetrical distribution and Koebner phenomenon (trauma induced LP)
- Papules = red turning violaceous
- Flat topped polygonal and small diameter
- Surface network of fine white striations = Wickham’s striae
How can lichen planus affect nails
Can cause longitudinal grooving and pitting which is normally reversible and can also cause irreversible nail loss
How can lichen planus affect hair
May be follicular and permanent scarring alopecia is common
What is koebnerisation
The appearance of lichen planus secondary to trauma e.g. in an operation scar
Describe how lichen planus affects female genitalia
Vulvovaginal-gingival syndrome
- often unrecognised
- ulcerative and symptomatic
- progressive vulval disease leading to scarring
- reports of malignant transformation
What is lichenoid reaction
Clinically and histologically similar to lichen planus but has an identifiable aetiology (drug induced or dental material related)
Describe lichenoid drug reactions
They can be unilateral/bilateral and can be ulcerative
There is no pathognomonic histological feature
Withdrawal of the drug will reverse the lichenoid reaction
What drugs are associated with oral licheniod reaction
- Beta-blockers
- ACE inhibitors
- Diuretics
- Methyldopa
- Oral hypoglycaemics
- NSAIDs
- Gold salts
- Penicillamine
- Anti-malarials
- Allopurinol
Describe the clinical presentation of lichenoid reaction
It is sore especially if the erosive form occurs (this is more likely and it will affect the palate and tongue)
It is indistinguishable from lichen planus but will resolve on stopping the implicited drug and can have an asymmetric distribution if due to a reaction with local materials (e.g. amalgam)
What are oral contact hypersensitivity reactions
Subgroup of oral lichenoid reactions where the individual is sensitised to a component of dental materials e.g. amalgam alloy, nickel, mercury, gold, Bis-GMA
The lesion is confined to area of mucosa in direct contact with the restoration and there is a positive response to patch testing
Upon finding white reticular striae involving the buccal mucosa, which one of the extra oral findings is most consistent with this:
a. Brittle, spoon shaped nails
b. Butterfly malar rash
c. Scaly pink disc-shaped areas involving elbows + knees
d. Target or iris lesions involving the skin
e. Violaceous papules involving skin of the wrists and shins
E
What are the two types of lupus erythematous and what are each of these
- Systemic lupus erythematous = multi systemic autoimmune disease where autoantibodies are generated against autoantigents e.g. ANA and this involves vascular and connective tissues
- Discoid lupus erythematous = scaly atrophic plaques in sun exposed skin which isn’t autoimmune
Outline the presentation of systemic lupus erythematous
- F > M
- Multisystem involvement with serological/haematological change
- Facial butterfly rash (Malar rash) which spares nasolabial folds
- Photosensitivity, discoid lesions, diffuse alopecia, and vasculitis
- Sun exposure may trigger acute systemic flares
Outline the presentation of discoid lupus erythematous
- F > M
- May involve oral and genital mucosa, skin and hair
- Round oval plaques = red, scaly, white keratin plugs
- Scarring can cause alopecia
- Sun protection