Treatment of Acanthosis Nigricans With Tretinoin

Abstract

A 55-year-old Indian man presented to the dermatology service at The Johns Hopkins Hospital, Baltimore, Md, with a chief complaint of discoloration and thickening of the skin of his axillae, popliteal fossae, the dorsal surface of his toes, and the posterior aspect of his neck. He also complained of a generalized darkening of his complexion. These changes began 12 weeks after starting nicotinic acid, at an oral dose of 500 mg three times a day, for the treatment of hypercholesterolemia. After 16 weeks of treatment with nicotinic acid, his total serum cholesterol value had dropped from 7.24 to 6.10 mmol/L; however, the skin changes were cosmetically unacceptable. His medical history was significant for myocardial infarction and three-vessel coronary artery bypass surgery. He was otherwise in good health, and consultation with his internist revealed no evidence of malignancy or endocrine dysfunction.On physical examination, he had symmetrically distributed, velvety, hyperpigmented plaques in the distribution noted above. The remainder of his physical examination showed normal findings. DIAGNOSIS Acanthosis nigricans induced by treatment of hypercholesterolemia with nicotinic acid.THERAPEUTIC CHALLENGE Treatment of acanthosis nigricans consists primarily of a search for and then treatment of underlying malignancy or endocrinopathy. In most cases of acanthosis nigricans, however, as when induced by nicotinic acid, the condition is solely of cosmetic concern. Acanthosis nigricans following treatment with nicotinic acid resolves on discontinuation of the medication. In treating hypercholesterolemia, however, withdrawal of nicotinic acid results in a rebound increase in the serum cholesterol value. Thus, reversal of nicotinic acid-induced acanthosis nigricans by a method other than medication withdrawal would be advantageous. SOLUTION Because of the hyperkeratotic nature of acanthosis nig¬ ricans, and the favorable response of many other hyper¬ keratotic conditions to topical tretinoin (retinoic acid),1 we attempted a therapeutic trial of tretinoin treatment of pseudo-acanthosis nigricans. The untreated skin of the right axilla served as a control (Fig 1) and was unchanged in clinical appearance over the 2-week trial period. Topical application of 0.1 % tretinoin gel two times daily for 2 weeks to the skin of the left axilla produced a nearly complete resolution of his clinical lesions (Fig 2). Fig 1.-Untreated right axilla at the end of the 2-week trial period, showing velvety, verrucous, hyperplgmented plaques of acanthosis ni¬ gricans. Fig 2.-Skin of the left axilla after topical application of 0.1% tretinoin gel twice daily for 2 weeks, showing clinical resolution of the cutaneous thickening and hyperpigmentation of acanthosis nigricans. Downloaded From: http://archderm.jamanetwork.com/ by a Karolinska Institutet University Library User on 06/02/2015

Unilateral Nevoid Acanthosis Nigricans with a Submammary Location

“…The lesions were gradually flattened and the brownish pigmentation was decreased after topical treatment with tretinoin. This was probably due to shedding of hyperkeratotic squamae, as was suggested in a previous report 11 .…”

“…But further studies on unilateral nevoid AN are necessary to determine the pathogenesis. Although no guideline or consensus for the treatment of unilateral nevoid AN has been proposed due to its rare incidence, a case of ordinary AN treated with topical tretinoin was reported in 1991 11 . Moreover, Lee et al 5 achieved clinical improvement with topical tretinoin treatment in a patient with unilateral nevoid AN.…”

Confluent and Reticulated Papillomatosis: A Case with Concurrent Acanthosis nigricans Associated with Obesity and Insulin Resistance

“…It has been reported that the etretinate therapy improved glucose tolerance and insulin responses in pa tients with psoriasis [20], Impaired glucose tolerance in our case, however, remained during and after the etretinate therapy. Since retinoids have beneficial effects on various keratinization disorders including AN [21,22], our ther apeutic efficacy might support the concept of CRP as being the keratinization defect. Weight reduction diet therapy occasionally improves the lesion.…”

Acrokeratosis Paraneoplastica with Adenocarcinoma of the Colon Treated with Topical Tretinoin

“…We treated her with topical tretinoin because of the favorable response to many hyperkeratotic skin conditions, such as acanthosis nigricans or psoriasis. The effects of topical tretinoin on the epidermis include the induction of epidermal mitotic activity, the shedding of desmosomes and tonofibrils, and the production of a mucin-like material 16 . These actions affect cell growth, differentiation, and morphogenesis and alter cell cohesiveness 17 .…”