lichen nitidus

Epidemiology

• uncommon to rare, incidence 0.03% of general population
• affects mostly children & young adults

Pathology

• benign disorder; no associated complications or mortality
• lymphohistiocytic inflammatory cell infiltrate close to epidermis
• granulomas may be present
• basal cell hydrops degeneration
• overlying epidermis is flattened & parakeratotic

Genetics

• familial cases have been described

Clinical manifestations

• generally asymptomatic
• occasional pruritus
• flat-topped, skin-colored papules 1-3 mm
• most common sites of involvement
  • trunk
  • flexor aspects of upper extremities
  • dorsal aspects of hands
  • genitalia
• mucous membranes & nails may also be affected
• nail changes include pitting, ridging, splitting, & linear striations

Laboratory

• skin biopsy

Differential diagnosis

• mimics & can coexist with lichen planus

Management

• no established treatment guidelines
• treat as lichen planus

More general terms

• lichenification