Tumours of non-endocrine origin may exert deleterious effects by elaborating active principles which disturb body regulation. Systemic manifestations are fairly common with neoplasms of the lung, kidney, gastro-intestinal tract and thymus. The secretion of these tumours may have a known chemical structure (serotonin), may present hormone-like action (parathormone, antidiuretic hormone, insulinoid), or have well-defined biological properties (erythropoietin, gastrin-like principle). Tumours may stimulate endocrine glands by an unknown mechanism, producing disorders such as Cushing's syndrome, hypercalcemia, gynecomastia and hypoglycemia. Thymomas may be associated with autoimmune diseases. Tumours may extensively utilize or excrete some metabolite (glucose) or electrolyte (Na or K). Awareness of the systemic effects of various neoplasms may lead to an early diagnosis and proper treatment of these manifestations. (+info)
Common hyperpigmentation disorders in adults: Part II. Melanoma, seborrheic keratoses, acanthosis nigricans, melasma, diabetic dermopathy, tinea versicolor, and postinflammatory hyperpigmentation.
(10/88)
Nevi, or moles, are localized nevocytic tumors. The American Cancer Society's "ABCD" rules are useful for differentiating a benign nevus from malignant melanoma. While acanthosis nigricans may signal an underlying malignancy (e.g., gastrointestinal tumor), it more often is associated with insulin resistance (type 2 diabetes, polycystic ovary syndrome) or obesity. Melasma is a facial hyperpigmentation resulting from the stimulation of melanocytes by endogenous or exogenous estrogen. Treatments for melasma include bleaching agents, laser therapy, and a new medication that combines hydroquinone, tretinoin, and fluocinolone acetonide. Lesions that develop on the shins of patients with diabetic dermopathy often resolve spontaneously; no treatment is effective or recommended. Tinea versicolor responds to treatment with selenium sulfide shampoo and topical or oral antifungal agents. Postinflammatory hyperpigmentation or hypopigmentation can occur in persons of any age after trauma, skin irritation, or dermatoses. (+info)
Simultaneous deficiency in CD28 and STAT6 results in chronic ectoparasite-induced inflammatory skin disease.
(11/88)
A mouse lacking CD28, a T-cell costimulatory molecule, and STAT6, a transcription factor that mediates interleukin-4 (IL-4) signaling, was developed from parental CD28- and STAT6-deficient mice. STAT6/CD28(-/-) BALB/c mice that were 8 weeks old had a normal phenotype, and IL-4 production was induced following infection with nematode parasites. Unexpectedly, when they were between 4 and 8 months old, all mice examined spontaneously developed severe chronic dermatitis associated with pronounced numbers of Demodex ectoparasites. In addition, pronounced CD4 and CD8 T-cell infiltrates in the dermis and subcutaneous fat, increased serum immunoglobulin G2a levels, and lymphadenopathy associated with increased gamma interferon and IL-12 expression were observed. Single-knockout siblings lacking either CD28 or STAT6 had a phenotype similar to that of BALB/c wild-type controls. To distinguish whether the ectoparasite Demodex or the Th1 immunity was the proximal cause of the inflammatory skin disease, STAT6/CD28(-/-) mice were treated with a miticide that eliminated the ectoparasites. This treatment markedly reduced the severity of the dermatitis and the associated lymphoid infiltrates. These findings suggest that ubiquitous ectoparasites, which are generally considered to be commensal, may contribute to disease when specific molecules required for an effective Th2 response are blocked. (+info)
Clinical profiles, occurrence, and management of adolescent patients with HAIR-AN syndrome.
(12/88)
The syndrome of hyperandrogenism, insulin resistance, and acanthosis nigricans (HAIR-AN) is a subphenotype of the polycystic ovary syndrome. It is one of the most common causes of menstrual problems, hyperandrogenic symptoms, and insulin resistance among young women. Review of clinical data in an outpatient adolescent clinic showed that of the 1,002 young women (ages 10-21 years) attending the clinic over a 2-year period, 50 (5%) were diagnosed with HAIR-AN syndrome. Mean age of the patients was 15.5, initial mean weight at diagnosis was 94.5 kg, and the mean BMI was 33.33 kg/m2. Patients were treated with a weight-stabilization and -reduction program, oral contraceptive pills, and in most cases metformin. Of the patients, 80% were compliant with the follow-up and treatment regimen, 60% maintained or reduced their weight, 95% had regular menstrual cycles, and in most patients, the acne and/or hirsutism were the same or better than at the start of treatment. We conclude that HAIR-AN syndrome is a common disease in young women and multifaceted, aggressive treatment appears to be effective in reducing the severity of symptoms and preventing further consequences. (+info)
Type 2 diabetes and impaired glucose tolerance in European children and adolescents with obesity -- a problem that is no longer restricted to minority groups.
(13/88)
BACKGROUND: The incidence of childhood obesity and type 2 diabetes is an increasing problem in Europe. We determined the prevalence of impaired glucose regulation in a predominantly Caucasian cohort of 491 children and adolescents with obesity. METHODS: Fasting glucose and insulin levels were determined in all 491 subjects. Patients with an abnormal fasting glucose or with additional risk factors (positive family history of type 2 diabetes, acanthosis nigricans, hyperlipidemia; n=102) underwent an oral glucose tolerance test (OGTT; 1.75 g glucose/kg body weight). Homeostasis model assessment was used to estimate insulin resistance in all subjects. The insulin sensitivity index was determined in those subjects who underwent an OGTT. Screening for mutations in the melanocortin 4 receptor (MC4R) gene and the coding region of the brain-derived neutrophic factor (BDNF) in 37 patients with an impaired glucose tolerance was performed by WAVE analysis. RESULTS: Out of the total of 491 patients, 12 had an abnormal fasting glucose level. Of the 102 patients who underwent an OGTT, 37 had impaired glucose tolerance; 6 out of the 102 patients were diagnosed with type 2 diabetes. Eighty-eight per cent of patients with abnormal glucose tolerance and 66% of patients with type 2 diabetes were Caucasian. Insulin resistance indices correlated well with the degree of abnormal glucose tolerance. Using the screening algorithm for type 2 diabetes as advocated by the American Diabetes Association, 68% of patients with impaired glucose tolerance and 66% of patients with type 2 diabetes would have been missed. No abnormalities in the MC4R and BDNF genes were detected. CONCLUSIONS: Impaired glucose tolerance and type 2 diabetes are far more common in obese European children of Caucasian origin than previously thought. Using fasting glucose levels as the main screening tool appears to be insufficient in detecting these children. (+info)
Islets secretory capacity determines glucose homoeostasis in the face of insulin resistance.
(14/88)
BACKGROUND: Debate surrounds the relative importance of impaired beta-cell secretory function versus insulin resistance in type 2 diabetes. We therefore defined insulin secretion and sensitivity in patients with impaired glucose homoeostasis of varying aetiology and duration. METHODS: 126 consecutive patients undergoing an oral glucose tolerance test (OGTT) between 1999 and 2003 were included. Whole-body insulin sensitivity index (ISI) and insulinogenic index derived from the OGTT were determined in 32 healthy controls, 65 type 2 diabetic patients, 15 patients with acromegaly, 10 patients with insulinoma, and 4 patients with HAIRAN syndrome. RESULTS: Median ISI (quartiles Q25-Q75) of healthy controls and of patients with insulinoma were similar (3.5 [2.8-5.6] and 3.2 [1.7-4.2] respectively) but significantly decreased in patients with acromegaly, type 2 diabetes, and HAIRAN syndrome (2.8 [1.8-3.3], 1.9 [1.4-3], and 0.8 [0.6-1.3] respectively). Despite the decrease in ISI, patients with HAIRAN syndrome and acromegaly maintained normal glucose tolerance by adapting insulin secretion as reflected in the insulinogenic index (106.5 [90.4-127.5] and 49 [24.4-89] in HAIRAN and acromegaly respectively, versus 46.9 [27.3-66.7] in controls). In contrast, type 2 diabetic patients failed to adapt and displayed severely hampered insulin secretion (insulinogenic index of 7.6 [3.8-14.7]). Furthermore, the level of the insulinogenic index correlated significantly with duration of diabetes and HbA1c, which was not the case for the ISI. Insulinoma patients had a decreased insulinogenic index (38.7 [32-83.8]), leading to impaired glucose tolerance despite normal ISI. CONCLUSIONS: The data are compatible with the notion that beta-cell function rather than insulin sensitivity determines the evolution of hyperglycaemia. (+info)
Rabson-Mendenhall syndrome.
(15/88)
Rabson-Mendenhall syndrome is characterized by growth retardation, dysmorphisms, lack of subcutaneous fat, acanthosis nigricans, enlarged genitalia, hirsutism, premature and dysplastic dentition, coarse facial features, paradoxical fasting hypoglycemia and post-prandial hyperglycemia, extreme hyperinsulinemia and pineal hyperplasia. We describe a six-month-old female child with physical features suggestive of the Rabson-Mendenhall syndrome. The child also had medullary nephrocalcinosis. (+info)
Acanthosis nigricans in association with congenital adrenal hyperplasia: resolution after treatment. Case report.
(16/88)
A case is described of a three-day-old female with salt wasting type of 21-hydroxylase deficient congenital adrenal hyperplasia who presented with acanthosis nigricans of both axillae. Following corticosteroid and mineralocorticoid therapy for disease, the acanthosis nigricans resolved. It is believed that this is the first reported case of acanthosis nigricans occurring in association with congenital adrenal hyperplasia, a phenomenon that resolved after treatment. We speculate that the acanthosis nigricans resulted from hyperandrogenemia or other unknown factors in our patient. (+info)