Lichen planus

Background

  • Uncommon disorder of unknown cause, likely T-cell mediated autoimmunity against basal kertinocytes
  • Most common in patients aged 30 to 60 years
  • HCV association is controversial
  • Drug exposure can resemble idiopathic lichen planus

Affected areas

  • Skin (cutaneous lichen planus)
  • Oral cavity (oral lichen planus)
  • Genitalia (penile or vulvar lichen planus)
  • Scalp (lichen planopilaris)
  • Nails
  • Esophagus

Clinical Features

Cutaneous Lichen Planus

Predominantly on ankles and volar surface of wrists

  • Four “P’s”
    • Pruritic
    • Purple
    • Polygonal
    • Papules or plaques
  • Wickham’s striae: Fine white lines visible on surface of papules or plaques
  • Koebner reaction: Lesions develop in areas of trauma (e.g., scratching)

Cutaneous variants

Hypertrophic lichen planus

  • Intensely pruritic, flat-topped plaques
  • Common sites are extensor surfaces of lower extremities

Atrophic lichen planus

  • Violaceous, round or oval, atrophic plaques
  • Common sites are legs
  • Often resolution of annular or hypertrophic lesions

Annular lichen planus

  • Violaceous plaques with central clearing
  • Common sites are penis, scrotum, and intertriginous areas

Bullous lichen planus

  • Vesicles or bullae within existing lesions
  • Common sites are legs

Actinic lichen planus (lichen planus tropicus)

  • Photodistributed eruption of hyperpigmented macules, annular papules, or plaques
  • Most common in Africa, Middle East, and India

Lichen planus pigmentosus

  • Gray-brown or dark brown macules or patches
  • Sun-exposed or flexural areas
  • Pruritus minimal or absent

Inverse lichen planus

  • Erythematous to violaceous papules and plaques
  • Intertriginous sites (e.g., axillae, inguinal creases, inframammary area, limb flexures)
  • Hyperpigmentation is common
  • Scales and erosions may be present

Overlap syndromes

  • Lichen planus pemphigoides
  • Lichen planus-lupus erythematosus overlap syndrome

Other forms of lichen planus

  • Nail lichen planus
    • Varies from minor atrophy to total nail loss
  • Lichen planopilaris (follicular lichen planus)
    • Keratotic papules that may coalesce into plaques
    • Classic site is the scalp
    • May be in other body sites (e.g., Graham-Little-Piccardi-Lasseur syndrome)
    • Untreated, can result in scarring and permanent alopecia
  • Oral lichen planus
    • Painful, frequent loss of appetite
    • May lead to secondary candida infection
  • Genital lichen planus
    • Involves glans of penis or epithelium of vulva, vestibule, vagina, and mouth
    • Often resistant to treatment
  • Esophageal lichen planus
    • Associated dysphagia or odynophagia
    • Concomitant oral, genital, or cutaneous lichen planus
  • Otic lichen planus
    • Erythema, induration, and stenosis of external auditory canal
    • Thickening of TM
    • Otorrhea
    • Hearing loss

Differential diagnosis

The differential diagnosis for lichen planus includes:

  • Chronic graft-versus-host disease
  • Psoriasis
  • Atopic dermatitis
  • Lichen simplex chronicus
  • Subacute cutaneous or discoid lupus erythematosus
  • Pityriasis rosea
  • Secondary syphilis
  • Prurigo nodularis
  • Paraneoplastic pemphigus/paraneoplastic autoimmune multiorgan syndrome (PAMS)
  • Oral leukoplakia
  • Oral candidiasis
  • Pemphigus vulgaris, benign mucous membrane pemphigoid
  • Lichenoid drug eruption
    • Antimicrobials: aminosalicylate sodium, ethambutol, griseofulvin, ketoconazole, streptomycin, tetracycline, trovafloxacin, isoniazid
    • Antihistamines: ranitidine, roxatidine
    • Antihypertensives/antiarrhythmics: ACE-inhibitors, doxazosin, beta blockers, methyldopa, prazosin, nifedipine, quinidine
    • Antimalarial drugs: chloroquine, hydroxychloroquine, quinine
    • Antidepressants/anxiolytics/antipsychotics/AEDs: amitriptyline, carbamazepine, chlorpromazine, levomepromazine, methoprazine, imipramine, lorazepam, phenytoin
    • Diuretics: thiazide diuretics, furosemide, spironolactone
    • Antidiabetics: sulfonylureas
    • Metals: gold salts, arsenic, bismuth, mercury, palladium, lithium
    • NSAIDs
    • Proton pump inhibitors: omeprazole, lansoprazole, pantoprazole
    • Lipid lowering drugs: pravastatin, simvastatin, gemfibrozil
    • TNF-alpha antagonists: infliximab, adalimumab, etanercept, lenercept
    • Varia: allopurinol, bleomycin, cinnarizine, cyanamide, dapsone, hydroxyurea, hepatitis B-vaccine, imatinib, immunoglobulins, interferon alfa, l-thyroxin, levamisole, mesalamine, methycran, penicillamine, procainamide, pyrimethamine, pyrithioxine, quinacrine, sildenafil, sulfasalazine, terbinafine, trihexyphenidyl, ursodeoxycholic acid

Diagnosis

  • Clinical diagnosis
  • Workup outside of ED may include:
    • Punch biopsy or shave biopsy
    • Immunofluorescence studies if bullous lesions present
    • Routine HCV testing controversial

Management

Cutaneous

  • Self-limiting disease, usually resolves within 8-12 months
  • First-line
    • Topical corticosteroid
      • High potency (e.g., trunk, extremities)
        • 0.05% betamethasone dipropionate cream/ointment BID
        • 0.05% diflorasone diacetate cream/ointment BID
      • Mid- or low-potency (e.g., intertriginous areas, facial skin)
    • Intralesional corticosteroids (hypertrophic lichen planus)
  • Second-line therapy
    • For generalized disease or local corticosteroid-refractory disease
      • Oral glucocorticoids
        • Optimal dose/duration unknown
        • 30 to 60 mg qd 4-6 weeks followed by 4-6 week taper
      • Phototherapy (e.g, Ultraviolet B, psoralen plus Ultraviolet A)
      • Oral acitretin

Genital

  • Topical corticosteroids or topical calcineurin inhibitors

Lichen planopilaris

  • Topical corticosteroids or intralesional corticosteroids

Oral

  • Topical corticosteroids

Nail

  • Systemic or intralesional corticosteroids

Disposition

  • Outpatient treatment

Prognosis

Cutaneous lichen planus

  • Remits within 1 to 2 years

Oral, genital, scalp, and nail lichen planus

  • More persistent and resistant to therapy
  • Squamous cell carcinoma risk is unclear (highest risk with erythematous or erosive oral and genital lichen planus)

Monitor for medication adverse effects

External Links

References

  • Goldstein, BG, Goldstein, AO, Mostow, E. Lichen planus. In: UpToDate, Dellavalle, RP, Callen, J (Ed), UpToDate, Waltham, MA, 2017.