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Showing posts from March, 2013

Thoracic cage injuries - simple and complicated

Acanthosis nigricans - cause and significance

Acanthosis nigricans is a hyperpigmented velvety lesion usually found in the neck and the axillary region. It can also be seen elsewhere e.g. the belt line, creases over the dorsal surface of fingers. The palms and soles are typically not involved. Pathologically, it is characterized by an increased number of melanocytes associated with hyperkeratotic epidermal papillomatosis. It is strongly associated with insulin resistance but it is a non-specific condition and can also be found in obesity, polycystic ovarian syndrome, endocrine diseases like acromegaly and Cushing's syndrome, as well as some malignant tumours. The severity of the acanthosis nigricans correlates with the degree of insulin resistance and the level of serum insulin. The exact mechanism of its formation is still unclear but it is speculated that there are related IGF-1 receptors in the skin which are activated by ambient hyperinsulinemia. If the insulting factor is removed, there may be a regression of the

Classification of Diabetes Mellitus

Diabetes is divided into 4 different classes: 1) Type 1 diabetes (results from beta-cell destruction, usually leading to absolute insulin deficiency) 2) Type 2 diabetes (results from a progressive insulin secretory defect on the background of insulin resistance) 3) Other specific types of diabetes due to other causes, e.g. genetic defects in beta-cell function, genetic defects in insulin action, diseases of the exocrine pancreas (such as cystic fibrosis, pancreatitis) and drug- or chemical-induced (such as in the treatment of HIV/AIDS or after organ transplantation) 4) Gestational diabetes mellitus (GDM) (diabetes diagnosed for the first time during pregnancy that is not clearly overt diabetes).