Lichen Simplex Chronicus

1. 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

4. Lichen Simplex Chronicus

5. 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

6. PrurigoNodularis • Chronic • Etiology: unknown • Contribute factors: atopic dermatitis anemia hepatic diseases pregnancy renal failure lymphoproliferative disease photodermatitis gluten enteropathy stress insect bites.

9. PrurigoNodularis

10. 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