[Generalized familial acanthosis nigricans associated with hypochondroplasia].

None of them reported any illness or habitual use of medication. We observed that all 3 patients examined presented small stature, with short limbs. The patient reported that all except 1 of her siblings were of small stature, as was 1 of her children. Radiological examinations of the patient revealed shortened long bones diagnostic of hypochondroplasia and similar results were seen in her son. Skin biopsy revealed hyperkeratosis and papillomatosis with moderate irregular acanthosis (Figure 2). In order to rule out any systemic disease associated with acanthosis nigricans, studies were requested for the patient, sister, and niece, including: blood tests, coagulation and general biochemistry, insulin and C-peptide, testosterone, dehydroepiandrosterone sulfate levels, and tumor markers. All the results were completely within normal ranges. Benign familial AN is characterized by presence at birth and progression in early infancy, with cutaneous changes becoming more prominent in puberty and then stabilizing or diminishing later. Lesions tend to be located in folds, although in some cases they reach an unusual extension and intensity— probably when onset occurs early with the ensuing long period of development. Prurutis is uncommon. 7 The condition is transmitted in autosomal dominant form with variable penetrance and it is not normally associated with any endocrine or congenital abnormality. We present a case of benign familial AN, with the classic clinical characteristics, associated with hypochondroplasia. Although we could not examine all the cases in this family, autosomal dominant inheritance appears to be present (Figure 3) as is normally the case. Benign familial AN is 1 of the usual classifications of the disease, although very few cases have been described. This could be due to the absence or minimal extent of associated symptoms and the hereditary nature of the disorder whereby patients do not consider the condition relevant or worthy of reporting to a physician. Even though there are generally no associated systemic alterations patients should be To the Editor: Acanthosis nigricans (AN) is a proliferative epidermal disorder expressed clinically in the form of velvety brown plaques in skin folds, although other parts of the skin and mucosa can occasionally be affected. New associations and peculiar clinical forms have been added to classifications of the disease since Pollitzer 1 and Janovsky 2 first reported cases of AN associated with neoplasia. There are currently 8 accepted types of AN, listed by Schwartz 3 as: benign, associated with obesity (pseudoacanthosis nigricans), syndromic, paraneoplastic, acral, unilateral, …