​Dermatology - Lichen Simplex Chronicus

​Dermatology - Lichen Simplex Chronicus
Lichen simplex chronicus is a specific, localized manifestation of lichenification that occurs in distinct plaques as a result of continuous rubbing and scratching. This condition manifests in persons who are at least 20 years old and is more prevalent among women. If rubbing or scratching is not ceased, this condition can persist for several decades.
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The skin exhibits heightened sensitivity to tactile stimuli and experiences itching in reaction to even the slightest external triggers. The symptoms include pruritus, which commonly occurs in paroxysms. The skin that has become lichenified elicits a pleasurable sensation when scratched, and stroking it becomes a habitual and reflexive response.

A dense layer of lichenification, resulting from the merging of tiny papules, is noticeably thicker; skin patterns (barely discernible in healthy skin) are intensified and easily evident. Individuals with deeply pigmented skin may exhibit hyperpigmented excoriations that initially appear as dull red and gradually turn brown or black. Lesions can be either solitary or present in several plaques, and are commonly found in the nuchal region (in women), scalp, ankles, lower legs, upper thighs, outer forearms, vulva, pubis, anal area, scrotum, and groin. Lichenification in individuals with dark skin may have a distinctive "follicular" pattern.

The diagnosis is made based on clinical examination, and the differential diagnosis includes chronic pruritic plaque of psoriasis vulgaris, early stages of mycosis fungoides, contact dermatitis, and epidermal dermatophytosis.

Inform the patient that they must cease the act of rubbing and scratching. Topical glucocorticoid treatments or tar preparations, when applied with occlusive dressings, are beneficial for treating the legs and arms. The efficacy of including glucocorticoid in adhesive plastic tape is maintained while left for a duration of 24 hours.
A gauze roll dressing containing zinc oxide paste can be applied to a significant area of thickened skin, such as the calf, known as lichenification. This dressing, also known as an Unna boot, can be left in place for a maximum of one week. Intralesional administration of triamcinolone is frequently highly efficacious in treating minor lesions (3 mg/mL); however, using greater dosages may lead to the development of atrophy. Administering oral hydroxyzine, at a dosage of 25-50 grams before bedtime, may provide assistance.