Lichen amyloidosis (LA) is a form of primary localized cutaneous amyloidosis (PLCA) characterized by bilateral intensely itchy domed scaly hyperkeratotic papules. Lichen amyloidosis is rare and affects men more than women. It is uncommonly seen in the western world but more prevalent in Asia. These papules most typically affect the shins and occasionally the arms and torso. Lichen amyloidosis has been reported in association with autoimmune disorders and after prolonged exfoliation and friction of affected skin. We present a 40-year-old woman with LA. In LA, the characteristic histological finding is apple-green birefringence of Congo red-stained preparations observed under polarized light. However, this is not always strongly positive, as in our patient. Other findings may include eosinophilia, periodic acid-Schiff positivity, staining with thioflavin T, and metachromasia after staining with crystal violet or methyl violet. Treatment of LA is difficult and complete clinical remission is seldom achieved. Recent trials revealed beneficial outcomes with topical calcipotriol, phototherapy, acitretin, cyclophosphamide, and laser treatments. A combination of acitretin, antihistamines, topical steroids, and hydrocolloid dressings have been beneficial in our patient with LA.

Prurigo nodularis (PN) is a highly pruritic skin condition that is caused by chronic scratching. It occurs in patients with chronic itch and is characterized by multiple hyperkeratotic papules and nodules. The pathogenesis of PN is unclear, but involves a complex interplay of numerous pathways including neurogenic and inflammatory factors. As such, PN is very difficult to treat and patients are often refractory to multiple medications before finding a treatment that is effective. We present a woman with a 20-year history of exuberant prurigo nodularis who failed multiple therapies, including dapsone, azathioprine, mycophenolic acid, prednisone, topical steroids, and phototherapy. She only obtained significant relief of chronic pruritus and lesion flattening with thalidomide 100mg daily. Thalidomide is an antipruritic and anti-inflammatory agent that has shown to be very effective in treating a variety of dermatologic conditions. However, its use today is limited by concerns for its teratogenic and neuropathic side effects. With strict adherence to medication protocols, these adverse effects can be minimized. As such, thalidomide should be considered for patients with refractory dermatologic conditions.