[Successful symptomatic tazarotene treatment of juvenile acanthosis nigricans of the familial obesity-associated type in insulin resistance].

An 11-year-old boy suffering from morbid obesity since infancy developed at age 9 a progressive brown-black hyperpigmentated and hyperkeratotic eruption in the neck and axillary region with minor involvement of both groins. Based on this clinical picture, and confirmed by histopathology, we diagnosed acanthosis nigricans. Following a thorough endocrinological examination and because the patient's obese mother showed similar skin lesions, the disease was subclassified as a familial obesity-associated type of acanthosis nigricans associated with insulin resistance. In a right-left-comparison the affected skin of one body side was treated with tazarotene 0.05% versus urea 10%, once daily each. A great benefit for the tazarotene-treated over the opposite side could already be seen after three weeks which was also verified by dermatohistopathology. Three months after topical tazarotene treatment had been extended to both sides, the residual lesions were significantly improved. The highly satisfying, good result has been maintained up to now by a continuous topical retinoid treatment over 18 months, usually with an interval application regimen, i.e., 3 x per week.