II. Epidemiology
- Prevalence: 0.1-4% in United States
- Age usually 30-60 years
- Gender predominance: Slightly more common in women (especilly Perimenopause)
III. Pathophysiology
- Autoimmune mediated apoptosis of epithelial cells
- Involves CD8+ Cytotoxic T-Cells
IV. Associated Conditions
V. Signs: General
- Characteristics
- Classic 6Ps
- Wickham Striae
- Lacy, reticular white lines covering the lesions
- Koebner Phenomenon
- May form in lines related to scratching
- Postinflammatory Hyperpigmentation
- May occur with lesion resolution (especially in dark skin)
- Distribution
- Cutaneous lesions form on flexor surfaces of wrists, Forearms, legs
- Oral Lichen Planus (25%)
- Genitalia
- Glans penis with annular pattern (see below)
- Vulvar Lichen Planus
- Scalp Lichen Planus
- Nail Lichen Planus
- Irregular longitudinal grooves or ridges in the nail plate
- Subungual keratosis or Hyperpigmentation
VI. Types: Variants
- Annular Lichen Planus (10%)
- See Annular Lesions
- Rings of clustered lesions with central clearing
- May also form on penis and Buccal mucosa
- Atrophic Lichen Planus (rare)
- Hypertrophic Lichen Planus
- Forms on extensor surfaces (ankles, shins, PIP and DIP joint)
- Very pruritic
- Chronic with prominent scarring
-
Vesiculobullous Lichen Planus
- Classic Lichen Planus lesions form bullae or vessicles
- Typically on mouth, back, buttocks, or legs
- Linear Lichen Planus (<1%)
- Unilateral pruritic, purple, flat-topped Papules in a linear pattern on the extremities
VII. Diagnosis
- Classic polygonal lesions on the flexor surfaces may not require biopsy for diagnosis
- Biopsy findings
- Epidermal hyperplasia with saw pattern
- Hyperparakeratosis with granular cell layer thickening
- Basal layer with vacuolar alteration
- T-Cell infiltration of the dermal-epidermal junction
VIII. Differential Diagnosis
IX. Evaluation
X. Management: Cutaneous Lichen Planus
- See Oral Lichen Planus
- See Vulvar Lichen Planus
- See Pruritus Management
- Cutaneous Lichen Planus (non-genital)
- High potency Topical Corticosteroids
- Consider topical Calcineurin Inhibitors if refractory to Topical Corticosteroids
- Severe, diffuse Cutaneous Lichen Planus
- Prednisone 30-60 mg orally daily for 3-6 weeks and then taper over an additional 4-6 weeks
- Phototherapy (narrow band UVB) for 30-40 minutes each of 2-3 days per week
XI. Course
- Isolated skin lesions without mucosal lesions may resolve spontaneously within 1 to 2 years