Nevoid acanthosis nigricans: Report of four cases localized to the umbilicus.

Nevoid acanthosis nigricans is a rare, benign form of acanthosis nigricans. Of the 24 cases documented in the literature, only two are exclusively localized to the umbilicus. We present four cases of nevoid acanthosis nigricans localized to the umbilicus; in patients less than 25 years of age, with no known co-morbidities, three of whom were females. Two of the cases received, with good response, treatment based on topical calcipotriol, a medication not previously reported to be used for this indication. Contrary to other types of acanthosis nigricans, the nevoid acanthosis nigricans is not associated with any syndrome, endocrinopathy, obesity, medication, or neoplasia and it can be confused with other pathologies such as epidermal nevus or dermatosis neglecta.

Does insulin resistance co-exist with glucocorticoid resistance in the metabolic syndrome? Studies comparing skin sensitivity to glucocorticoids in individuals with and without acanthosis nigricans.

BACKGROUND: The metabolic syndrome is associated with increased risk for both diabetes and coronary artery disease, which insulin resistance alone does not satisfactorily explain. We propose an additional and complementary underlying mechanism of glucocorticoid resistance. RESULTS: Using acanthosis nigricans (AN) and skin vasoconstrictor (SVC) response to topically applied beclomethasone dipropionate as markers of insulin and glucocorticoid resistance, respectively, we compared anthropometric, biochemical, pro-inflammatory markers and the SVC response in subjects with AN in two studies: STUDY 1 was used to compare subjects with AN (Grade 4, n = 32), with those without AN (n = 68) while STUDY 2 compared these responses among a cross-section of diabetic patients (n = 109) with varying grades of AN (grade 0, n = 30; grade 1, n = 24; grade 2, n = 18; grade 3, n = 25; grade 4, n = 12). FINDINGS: In both studies there was an inverse relationship between AN Grade 4 and the SVC response, (P < 0.001). In STUDY 1, AN Grade 4 was associated with age, waist circumference, BMI, fasting blood glucose, plasma lipids and hs-CRP (P < 0.05). SVC was an independent predictor of CRP and those with combined AN and a negative SVC response, CRP levels were highest. In Study 2 when the SVC response in subjects with type 2 diabetes mellitus with varying degrees of AN was studied, it showed that for any degree of AN, the SVC response is more likely to be negative and was independent of gender and ethnicity. CONCLUSION: An absent SVC response represents a new biomarker for the metabolic syndrome and the exaggerated inflammatory response, which characterizes the metabolic syndrome, may be an outcome of deficient glucocorticoid action in vascular tissue.

Risk factors for medication-induced diabetes and type 2 diabetes.

OBJECTIVE: To compare the prevalence of risk factors in children aged <18 years diagnosed with medication-induced diabetes mellitus versus those diagnosed with type 2 diabetes. STUDY DESIGN: This retrospective observational study used data from a Canadian prospective surveillance study in which clinical features of new cases of type 2 diabetes (n = 225) and medication-induced diabetes (n = 58) were reported over a 2-year period. The presence of risk factors for type 2 diabetes (eg, obesity, family history of type 2 diabetes, ethnicity, acanthosis nigricans, hypertension, polycystic ovarian syndrome) was compared in the 2 groups using descriptive statistics and logistic regression. RESULTS: Compared with the children with type 2 diabetes, the children with medication-induced diabetes were more likely to be Caucasian (P < .0001) and less likely to be obese (P < .0001), to have a positive family history of type 2 diabetes (P = .0001), to have acanthosis nigricans (P < .0001) on clinical examination, and to have an obesity-related comorbidity, such as polycystic ovarian syndrome (P = .04), dyslipidemia (P = .02), hypertension (P = .04), or an elevated alanine aminotransferase level (P = .05). CONCLUSIONS: Evaluating for the typical risk factors for type 2 diabetes is not sufficient to identify all children at risk for developing medication-induced diabetes. Further studies are needed to help inform guidelines on screening for and prevention of medication-induced diabetes in children.

Comparison of metformin versus rosiglitazone in patients with Acanthosis nigricans: a pilot study.

BACKGROUND: Acanthosis nigricans (AN) is a skin condition commonly present on the neck of obese subjects. Obesity is often accompanied by insulin resistance and/or hyperinsulinemia. Metformin and rosiglitazone are 2 pharmacologic agents useful in conditions characterized by insulin resistance. OBJECTIVE: The aim of our study was to compare the efficacy of metformin versus rosiglitazone on AN lesions of the neck as well as their effects on metabolic and anthropometric variables. METHODS: This 12-week randomized, open-label pilot study involved overweight or obese subjects with AN treat with either metformin (n=4) or rosiglitazone (n=3). RESULTS: Only the rosiglitazone group showed a significant reduction in insulin levels. No effect on the severity of AN was observed, but modest improvements of skin texture occurred in both treatment groups. CONCLUSIONS: Metformin and rosiglitazone were well-tolerated. Although efficacy on skin lesions was very modest, their use in acanthotic subjects might be useful during longer treatment periods.

Dysmetabolic syndrome in a man with a novel mutation of the aromatase gene: effects of testosterone, alendronate, and estradiol treatment.

We present the fourth case of an adult man (29 yr old) affected by aromatase deficiency resulting from a novel homozygous inactivating mutation of the CYP19 (P450(arom)) gene. At first observation, continuing linear growth, eunuchoid body proportions, diffuse bone pain, and bilateral cryptorchidism were observed. The patient presented also a complex dysmetabolic syndrome characterized by insulin resistance, diabetes mellitus type 2, acanthosis nigricans, liver steatohepatitis, and signs of precocious atherogenesis. The analysis of the effects induced by the successive treatment with high doses of testosterone, alendronate, and estradiol allows further insight into the roles of androgens and estrogens on several metabolic functions. High doses of testosterone treatment resulted in a severe imbalance in the estradiol to testosterone ratio together with the occurrence of insulin resistance and diabetes mellitus type 2. Estrogen treatment resulted in an improvement of acanthosis nigricans, insulin resistance, and liver steatohepatitis, coupled with a better glycemic control and the disappearance of two carotid plaques. Furthermore, the study confirms previous data concerning the key role of estrogens on male bone maturation, at least in part, and regulation of gonadotropin secretion. The biopsy of the testis showed a pattern of total germ cell depletion that might be due to the concomitant presence of bilateral cryptorchidism. Thus, a possible role of estrogen in male reproductive function is suggested but without revealing a direct cause-effect relationship. Data from this case provide new insights into the role of estrogens in glucose, lipid, and liver metabolism in men. This new case of aromatase deficiency confirms previous data on bone maturation and mineralization, and it reveals a high risk for the precocious development of cardiovascular disease in young aromatase-deficient men.

[Effect of chronic blockade of the opiodergic receptor on insulin resistance in a hyperandrogenic woman]. / Efecto del bloqueo crónico del receptor opioidergico sobre la insulino-resistencia en una mujer hiperandrogénica.

We report a woman with insulin resistance associated with hyperandrogenism and acanthosis nigricans (HAIR-AN syndrome) treated during 30 days with the prolonged action opioid antagonist Naltrexone. During its administration, decreases in basal blood glucose and serum insulin, insulin and glucose response to a glucose load and plasma testosterone were observed. These findings suggest that opioid activity could play a critical role in the physiopathology of hyperinsulinemia in hyperandrogenic women.

Papilomatosis reticulada y confluente de Gougerot y Carteaud: reporte de un caso / Confluent and reticulated papillomatosis of Gougerot and Carteaud: report of a case

Se presenta un caso típico de papilomatosis reticulada y confluente (PRC) de Gougerot y Carteaud con buena respuesta al tratamiento tópico con vitamina A ácida. Se realiza un comentario general sobre la enfermedad y diagnósticos diferenciales