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
How can discoid lupus erythematous be managed
- Potent topical/intralesionsal corticosteroids
2. Antimalarials
A woman is through to have SLE, which one of the following findings from a blood investigation is most likely:
a. High ANCA antibody levels
b. High positive double stranded DNA antibody titre
c. High positive anti-desmoglein 1 and 3 antibody titre
d. Low ESR, high C-reactive protein
e. Weak positive ANA antibody titre
B
a. = granulomatosis
c. = pemphigus
d. = not autoimmune and suggests infection (pemphigus)
e. = found in patients with no conditions
Define a vesicle
Small fluid filled blister < 5mm in diameter
Define a bulla
Fluid filled large blister > 5mm in diameter (due to trauma or infection e.g. HSV Herpetic Whittlow)
List infectious blistering conditions
- Herpes simplex
- Herpangina
- Hand foot, mouth
- Herpes zoster
List autoimmune blistering conditions
- Pemphigus vulgaris
- Bullous pemphigoid
- Mucous membrane pemphigoid
- Linear IgA disease
- Dermatitis herpetiformis
List idiopathic blistering condiitons
- Angina bulls haemorrhagica
- Erythema multiforme
- Drug reactions
List collagen defective blistering conditions
Epidermolysis bullosa
What is varicella zoster virus (HHV3)
Herpes virus causing chicken pox and shingles
- Primary infection with chickenpox in non-immune
- Recurrence after reactivation as shingles can be a sign of underlying malignancy or immunosuppression
Describe the presentation of primary infection with varicella zoster virus
Chicken pox
- common in children
- itch maculopapular rash on back, chest, face
- presents 2-3 weeks after infection
- initial site is the upper respiratory tract (droplet infection)
Describe the presentation of herpes zoster recurrence
Shingles
- presents on trunk, affecting a single dermatome as the virus remains dormant in neurological tissue
- fluid filled vesicles contain the infection HZV virus
- underlying immunosuppression (AIDS, Hodgkin’s lymphoma, Organ transplant)
- often misdiagnosed in pre-dromal phase and there is no rash initially
- predilection for cranial nerves V and VII (facial presentation)
What is post-herpetic neuralgia
Lasting nerve pain in an area previously affected by shingles - this is because the latent Varicella zoster virus from dorsal root ganglion/ cranial nerve ganglion reactivates but is controlled by cell mediated immunity
What is dermatitis herpetiformis
Rare, chronic pruritic papulovesicular rash with small vesicles on urticated base presenting on the buttocks, elbows and knees
This is associated with gluten sensitive enteropathy (Coeliac disease)
Describe the oral presentation of dermatitis herpetiformis
Transient superficial blisters which become tender non-specific ulcers
Describe the histopathological findings of dermatitis herpetiformis
Localised splitting at basement membrane zone with speckled/ granular IgA immunofluorescence deposits involving the basement membrane of dermal papillae
Antigens for tissue transglutaminase
How is dermatitis herpetiformis treated
Dietary restriction with gluten-free diet and dapsone
What is erythema multiforme
It is a skin reaction triggered by infection (HSV, HIV, Hep, mycoplasma), medication or idiopathic causes
It is immune mediated type III (immune complex)
What does erythema multiforme target
Iris lesions, erythematous papules and blisters at the extremities (palms and soles) and mucous membranes
Describe the clinical presentation of oral lesions of erythema multiformis
Bullae/ erythematous base break rapidly into irregular ulcers which bleed and crust - the lips are more frequently involved (rare gingival involvement)
Describe the clinical presentation of skin lesions of erythema multiformis
Skin macule and papules, central, pale area surrounded by oedema and bands of erythema - iris type but can also be bullae
(looks like a target with central blistering and concentric rings of redness and white)
Outline the causes of erythema multiformis
- Infection = HSV, hepatitis viruses, mycoplasma, bacterial, fungal, parasites
- Drugs = NSAIDs, antifungals, barbiturates
- Systemic = SLE, malignancy, pregnancy
- Idiopathic
How is erythema multiformis treated
It is a self-resolving condition but can be managed by antivirals (acyclovir), corticosteroids and immunosuppressants
What is pemphigus vulgaris
A chronic organ-specific autoimmune blistering disease with circulating and tissue bound IgG autoantibodies directed against adhesion proteins of desmosomes
There is dissolution of cell-cell adhesion and intraepithelial blisters affecting the skin and mucosa
Outline the oral presentation of pemphigus vulgaris
Mouth involvement in most cases with following presentation:
- Oral bullae which are fragile and short lived
- Large shallow non-healing ulcers are typical
- Palate, buccal mucosa and gingival are most commonly affected
Describe the presentation of cutaneous pemphigus
Large non-healing erosions and ulcers of the skin which appear 3-4 months after mouth lesions (rare to see frank blisters)
How is pemphigus vulgaris managed
- Topical corticosteroids (Betamethasone mouthwash)
- Systemic corticosteroids (Prednisolone)
- Steroid-sparing agents (Azathioprine/Mycophenolate mofetil = longer onset)
- IV immunoglobulins (treats autoimune conditions)
What is mucous membrane pemphigoid
A rare, autoimmune blistering disease of middle aged/elderly which is chronic with an unknown aetiology
There are circulating and tissue bound antibodies against basement membrane zone (BP180 and BP230 antigens in hemidesmosomes)
Outline the clinical presentation of mucous membrane pemphigoid
Predominantly a mucosal disease - urogenital, conjunctiva, larynx and oesophagus; skin is rarely involved and scalp involvement leads to alopecia
The full thickness of epithelium lifts off underlying connective tissue and large tense bullae (blood-filled) break down to chronic painful erosions
What can happen if mucous membrane pemphigoid presents in the eye
There will be scarring because mucous membrane pemphigoid of the conjunctiva will draw in the eyelid and hairs onto the sclera which can cause blindness and is painful
How is mucous membrane pemphigoid managed
- Topical corticosteroids
- Oral prednisolone
- Oral dapsone and tetracyclines = anti-inflammatory
- Oral azathioprine and cyclosphosphamide = immunosuppressants
What is bullous pemphigoid
It affects the elderly and there is initial urticarial eruption preceding onset of blistering - large tense blisters involve skin of limbs, trunk and flexures and bullous pemphigoid can be localised to one site
How is bullous pemphigoid managed
- Systemic prednisolone +/- azathioprine
- The disease is self-limiting
A 68yo fit and well woman is diagnosed with pemphigus vulgaris and is started on 40mg oral prednisolone, which one of the following medications is she most likely to also be started on:
a. amlodipine
b. bendroflumethiazide
c. lansoperazole
d. fluconazole
e. ramipril
C = it is a PPI which will protect the gastric lining from damage by the corticosteroid (this is prophylaxis as corticosteroids can cause peptic ulceration)
