Lichen Simplex Chronicus Also known as Neurodermaitis Causes • Atopic dermatitis results in a higher probability of developing lichen simplex chronicus. • Common factors: Insect bites, scars, acne keloidalisnuchae,xerosis, venous insufficiency, and asteatotic eczema • Psychological factors appear to play a role in the development or exacerbation of lichen simplex chronicus. • Anxiety has been reported to be more prevalent in patients with lichen simplex chronicus. • Neurodermatitis is a term formerly used interchangeably with lichen simplex chronicus, suggesting a role of anxiety or obsession as part of the pathological process of developing lesions. Andrew’s Disease of the skin Fitzpatrick’s color atlas of dermatology Medical Therapeutic of Dermatology
Treatment • aimed at reducing pruritus and minimizing existing lesions because rubbing and scratching cause lichen simplex chronicus. • High Potency Topical steroids • are the current treatment of choice because they decrease inflammation and itch while concurrently softening the hyperkeratosis • Usually applied under plastic or biosynthetic or hydrocolloid dressings overnight or for continuous 3 to 7 day periods • Intralesional injection of corticosteroids • Will induce involution most rapidly and is often the therapy of choice • For infected lesions, a topical or oral antibiotic can be considered
PrurigoNodularis • Chronic • Etiology: unknown • Contribute factors: atopic dermatitis anemia hepatic diseases pregnancy renal failure lymphoproliferative disease photodermatitis gluten enteropathy stress insect bites.
Treatment • Topical, oral, and intralesional corticosteroids • to decrease inflammation and sense of itching • to soften and smooth out firm nodules • Menthol, phenol, pramoxine, capsaicin cream,15 vitamin D-3 ointment,16 and topical anesthetics are some other topical agents used to reduce pruritus