Lichen Planus Flashcards
most common age of onset of LP:
- middle aged adults (peaks at 40-50)
Male/female predominance
F>M
Pathogenesis:
- auto reactive T-lymphocytes attack basal keratinocytes in the skin, mucous membranes, hair follicles and/or nail units. - viruses, medications, and contact allergens have been implicated as cause of this reaction.
_____ is implicated in subset of oral ulcerative/erosive LP
Hepatitis C virus
_____ is associated with oral LP, and bullous LP in children (otherwise uncommon presentation)
- Hepatitis B (vaccine)
Contact allergens a/w oral LP:
- mercury amalgam, copper and gold
treatment for oral LP caused by contact allergen?
- remove the allergen (mercury amalgam, copper, gold)
Most common drugs implicated in drug induced LP:
- HCTZ, B-Blockers, ACE inhibitors, antimalarials, gold salts.
Classic finding on lesions of LP:
- Wickham striae
Drug induced LP clinically presents as_____ and spares the ______ regions of body
- more generalized, eczematous lesions, in a photo distribution - spares the oral mucosa and genitals
Look for ______ on histopath for drug induced LP.
- eosinophils
How long after drug can drug induced LP appear?
- up to one year!!
LP presents clinically as:
- purple, pruritic, planar, papules and plaques
LP lesions may exhibit______ phenomenon
- Koebner
Most common sites of LP:
- oral mucosa is #1!!! - ventral wrists/forearms #2 - dorsal hands, shins, genitalia, presacral area and neck
Histopathology of LP:
- wedge shaped hypergranulosis - orthohyperkeratosis - irregular acanthuses w/ “saw-toothed” rate ridges - vacuolar degeneration of the basal layer - apoptotic keratinocytes confined to basal layer with some in superficial dermis (Civatte bodies) - superficial dermal band-like (lichenoid) lymphocytic infiltrate
With exception of drug induced and hypertrophic LP, histopath will lack _____.
- eosinophils
With exception of drug-induced LP and oral LP, histopath will lack _____
- parakeratosis
Graham-Little-Piccardi-Lasseru syndrome presents with:
- scarring alopecia of scalp caused by LPP - non-scarring hair loss at pubic and axillary regions - follicular papule that appear as keratosis pillars - and classic LP lesions of skin and mucosa Picture B.Little eating a Graham cracker with these symptoms.
LP variants by location:
- genital - mucosal LP - nail LP - Inverse LP - palmoplantar LP - Lichen planopilaris
___ % of patients with cutaneous LP will have oral lesions.
- 50%
nail LP will present as:
- lateral thinning of nails - longitudinal ridges - pitting - dorsal pterygium
LPP presents as:
- erythema and perifollicular scale around hair follicle that can lead to scarring alopecia
LP variants based on appearance:
- classic - annular - atrophic - hypertrophic - ulcerative - linear - bulls - pemphigoides - pigmentosus
Annular LP typically affects the ____ or ____
- penis or axilla
atrophic LP usually occurs on ____ as ____
- legs - depressed or hyper pigmented lesions
Ulcerative LP affects the ____
- palmoplantar surfaces
Hypertrophic LP commonly occur on the _____ and are ____ (symmetric or asymmetric)
- shins and dorsal feet - symmetric - can be VERY PRURITIC
Bullous LP presents as:
- blisters that arise within chronic LP lesions
LP pemphigoides presents with blisters on ____ 2/2 ___ autoantibodies targeting ____
- blisters on uninvolved skin - IgG autoantibodies against BPAG 2
LP pigmentosus presents as_____, and typically occurs in Fitzpatrick type ___ skin
- grey brown macule on sun exposed areas of face and neck - type 3/4 skin
LP variants by cause:
- Actinic LP - Drug-induced LP
Actinic LP occurs in _____ patient population and presents as:
- young middle eastern adults - red/brown plaques on sun-exposed areas of face, neck and extremities
What do you NOT see on histology?
- parakeratosis or eosinophils - think of LP as the strict parent that does not let para or eos around!
LP histology
