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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Spontaneous hypoglycemia occurs when the blood sugar falls below 50 mg/dl (2.8 mmol/l) and when neuroglycopenic symptoms appear. For clinical differential diagnosis separation of the hypoglycemias into fasting and postprandial hypoglycemias is suggested. Fasting hypoglycemia may be a symptom of insulinoma. The most important diagnostic tool in detecting insulinoma is still the simultaneous determination of glucose and insulin in plasma during fasting. A raised insulin level during hypoglycemia renders the presence of an insulinoma suspect; during fasting there is an inappropriate fall in blood glucose in relation to the course of the plasma insulin concentration, resulting in an increased insulin-glucose ratio. Recently determination of the fasting proinsulin level has been recommended as raised concentrations are pathognomonic for the presence of insulinoma. Evaluation of postprandial hypoglycemia is performed by oral glucose tolerance test with late glucose concentration determinations after three and four hours. This makes it possible to differentiate between reactive hypoglycemia in mild diabetes mellitus and "functional" reactive hypoglycemia, the most frequent cause of hypoglycemia.
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PMID:[Hypoglycemia: clarification and etiology]. 624 74

Insulin is produced by beta cells in pancreatic islets of Langherans via a complex process of proteolytic conversion. A precursor molecule, proinsulin, is transported to the Golgi apparatus where it is packed into secretory granules. Maturation of the secretory granules is associated with conversion of proinsulin to insulin and C-peptide by enzymatic cleavage. Secretion of insulin into the bloodstream is accompanied by the release of small amounts of proinsulins. Insulin immunoassays consist of radioimmunoassays using polyclonal antisera which cross-react with proinsulins, and two-site assays using monoclonal antibodies. These immunometric assays have led to improvements in specificity and sensitivity as compared to radioimmunoassays. To determine reference values and limits, insulinaemia must be measured in normoglycaemic subjects with a normal body weight. Moreover, as insulinaemia is most often measured during stimulation tests, reference values must also be determined for the most common tests such as the oral glucose tolerance test or the intravenous glucose tolerance test. We report the analytical characteristics of insulin assays and review reference values and their interpretation. Wide-scale use of insulin assays remains a subject of research rather than a diagnostic application. Spontaneous hypoglycaemia, a disorder which can be caused by hyperinsulinism, insulinoma, insulin autoimmune syndrome and non-insulin-mediated factors, is almost the only clinical indication for the measurement of plasma insulin. Diabetes is diagnosed solely on the basis of chronic hyperglycaemia. Thus, measurement of plasma insulin has no clinical value in the diagnosis or management of diabetic patients, with the exception of rare cases including the syndrome of severe insulin resistance and abnormalities in beta-cell secretory products. Otherwise, insulin measurement is used in experimental investigations to study the pathophysiology of various disorders, especially diabetes. The reference and range of plasma insulin values are not yet clearly established, and the range of concentrations reported in the literature remains unsatisfactory. There is a need to standardise results and thereby improve comparability among studies.
Diabetes Metab 1999 Dec
PMID:Insulin assays and reference values. 1063 71

Recurrent episodes of hypoglycemia in patients with diabetes are often associated with the ongoing treatment regimen. However, despite changes in treatment modalities, assessment of the causes of hypoglycemia in nondiabetic patients in the presence of severe and recurrent hypoglycemia is very important. The treatment that had been provided for 6 years in a 67-year-old female patient with type 2 diabetes mellitus was discontinued due to hypoglycemic episodes that presented for the previous 2 years. The patient experienced persistent hypoglycemia after cessation of the treatment and was hospitalized for further examination. Spontaneous hypoglycemia with a final diagnosis of insulinoma was established following histopathologic evaluation and was relieved postoperation. Insulinoma is rarely encountered as a cause of hypoglycemia in patients with type 2 diabetes. Insulin-secreting tumors should be considered where hypoglycemic episodes occur despite discontinuation of insulin and other antidiabetic treatment with endogenous hyperinsulinemia being noncompliant with the blood glycemic levels.
J Diabetes Complications
PMID:A rare cause of hypoglycemia in a type 2 diabetic patient: insulinoma. 2240 76

Hypoglycemia is a common and feared complication of insulin therapy. As in type 1 and type 2 diabetes, people with cystic fibrosis related diabetes are also at risk for hypoglycemia related to insulin therapy. Spontaneous hypoglycemia is also common in patients with CF without diabetes, who are not on glucose lowering medications. Spontaneous hypoglycemia in CF may also occur during or after an oral glucose tolerance test. In this review, we will discuss the definition, epidemiology, pathophysiology and impact of hypoglycemia, with a focus on people with cystic fibrosis. We will also review strategies to manage and prevent hypoglycemia.
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PMID:Hypoglycemia in cystic fibrosis: Prevalence, impact and treatment. 3167 23