A-Z OF SKIN

The cause of lichen nitidus is unknown. There has been no infectious trigger identified to date. Very rarely, lichen nitidus may be familial.

Lichen nitidus presents with multiple skin colored or reddish-brown pinpoint to pinhead‐sized bumps, with a flat, shiny surface. In patients with darker skin, the lesions may appear whiter than their usual skin colour. The commonest sites affected include the inner arms, genitals, chest and abdomen. Nails and the mucous membranes may rarely be affected. It may be associated with itch, but this would be uncommon. New lichen nitidus lesions may arise due to trauma, known as Koebner phenomenon.

A few other uncommon clinical variants of lichen nitidus are:

• Palmoplantar – occurs on hands/feet
• Actinic – occurs on sun-exposed sites, usually in dark skinned patients in summer
• Vesicular – presents with blistering, usually on hands/feet
• Linear – lesions are arranged in a line
• Follicular spines – lesions have pointy spines
• Perforating – lesions are umbilicated and may appear to have protruding materials

There are no known associated internal organ problems with lichen nitidus.

The diagnosis is usually made by a dermatologist clinically. A skin biopsy may be taken to confirm the diagnosis.

In most cases, no treatment is required. If needed to control itchy, widespread or cosmetically disfiguring lesions options include:

• Sun avoidance (if actinic variant)
• Avoid trauma
• Topical corticosteroids
• Oral antihistamines
• Topical tacrolimus/pimecrolimus
• UV therapy including NUVB or PUVA (if not the actinic variant)

Rarely needed in severe cases:

• Oral steroids
• Oral retinoids
• Oral cyclosporine
• Isoniazid
• Itraconazole

In the majority of patients, lichen nitidus tends to resolve spontaneously within one to several years.

Lesions do not usually scar, however, may be replaced by post inflammatory hyperpigmented spots that tend to resolve in months to years