Lichen planus Flashcards
Definition and localization
Inflammatory skin disease, cell mediated, idiopathic, involves the nails, mucous membranes, genitalia, flexures, wrist, forearm and presacral area
Signs and symptoms
violet Flat-topped papules and plaques, pruritis, can be asymptomatic or painful, Small, polygonal-shaped. some papules are umbilicated, surface is slightly shiny or transparent + Wickham’s striae
fingernails have longitudinal ridges on them with ‘V-shaped’ nicks
lichen planopilaris
Pathogenesis
basal keratinocytes start presenting altered self-antigens on their surface on MHC1 and cytotoxic t-cells start attaking these cells. melanocytes get damaged too and release melanin–> skin becomes hyperpigmented
Types
Cutaneous and oral
Cutaneous resolves in 6 to 18 months while oral can be chronic
Triggers
antimalarial medications, Hepatitis C, other viruses, vaccines, bacteria, contact allergens, drugs, autoimmune disorders, stress
Types of oral LP
Atrophic, bollus, papular, erosive, plaquelike, reticular
Types of CLP
papular (classic), hypertrophic (shins and dorsal aspect of foot, extremely prutitic with scale), vesiculobullous, actinic, annular, atrophic, linear (in sites of scratching or trauma, koebner phenomenon), follicular, LP pigmentosus and LP pigmentosus-inversus
Diagnosis
based on its appearance, and can be confirmed with a biopsy that shows a “saw-tooth” shaped dermo-epidermal junction, and a thickened stratum granulosum or hypergranulosis + do Hepatitis C panel
Treatment
Remove trigger if known & it is self limited
flurinated topical corticosteroids for mild cases
For severe cases:
1) topical steroid ointments
2) Oral metronidazole
3) Oral acitretin (retinoid)
4) In widespread: UV-B therapy + Psoralen (makes the skin more sensitive to light therapy) for 8W
5) Other option: cyclosporine, Apremilast (PDE4 inhibitor), mycophenolate mofetil (immunosuppressant use in orogenital)
