Füsun Hamulu

Long-term treatment with acarbose for the treatment of reactive hypoglycemia

Objective: Acarbose, a potent alpha-glucosidase inhibitor, provides a new concept for the treatment of metabolic disorders, and particularly diabetes mellitus. It reduces the postprandial blood glucose increment and insulin response. For this reason the drug has been successfully used not only in the treatment of type 1 and type 2 diabetes, but also in the management of reactive hypoglycemia and dumping syndrome. The primary aim of the present study is to evaluate the long-term effect of acarbose in reducing hypoglycemic symptoms and influencing laboratory measurements in patients with the diagnosis of reactive hypoglycemia. Design and Methods: 21 non-obese (BMI <27 kg/m2) patients (6 males, 15 females) complaining of postprandial symptoms suggesting hypoglycemia and who showed blood glucose values of <54 mg/dI on one or more occasions during a 5 h oral glucose tolerance test (OGTT) were selected. Results: Before treatment, ingestion of glucose decreased plasma glucose levels at the 3rd and 4th hours, the lowest levels being 39 mg/dl and 45 mg/dl respectively. Eighteen patients had hypoglycemic symptoms during OGTT. Following 3 months of acarbose treatment, the lowest plasma glucose levels at the 3rd and 4th hours increased to 67 mg/dI and 75 mg/dI respectively. Plasma insulin and c-peptide levels were reduced between the 1st and 5th hours, but only the 1st and 2nd hour decrements were statistically significant. The area under the curve (AUC) between 0–300 minutes for insulin was not significant. Plasma glucose levels were significantly increased during the last 3 hours The AUC for glucose was not significantly changed. Frequency of hypoglycemic attacks was reduced from 4 times a week to 1. C-peptide levels in 24-hour urine collection did not change significantly: 45 μg/I and 56 μg/I respectively before and after treatment. Conclusions: These results confirm that acarbose may be of value in preventing reactive hypoglycemia by reducing the early hyperglycemic stimulus to insulin secretion, and in the treatment of reactive hypoglycemia.

Glucose Metabolism and Catecholamine Responses during Physical Exercise in Non-Insulin-Dependent Diabetes

Blood glucose, lactate, insulin, C-peptide, norepinephrine and epinephrine concentrations were determined in non-insulin-dependent diabetic patients and in healthy controls before, during and after moderate exercise, to evaluate the effects of physical exercise on glucoregulation. Ten diabetic and ten healthy control females bicycled 14 minutes at 60% of their maximal heart rates. In the diabetic patients, there were no significant changes in blood glucose levels post-exercise, while in controls the 60 minute post-exercise levels were higher than those measured in mid-exercise (p < 0.05). Lactate concentrations increased with exercise in both groups in a similar manner, with highest values at the end of exercise. No significant changes in insulin and C-peptide levels were induced with exercise in either group. Norepinephrine and epinephrine concentrations increased 2.5-3 fold with exercise in both groups (p < 0.05 for all values) but in the diabetics an earlier and prolonged catecholamine response was observed. We propose that catecholamines prevent hypoglycaemia during exercise when changes in insulin and C-peptide do not occur. In diabetic patients with good metabolic control, the glucoregulatory response to exercise is not worse than in anthropometrically similar controls with similar levels of fitness.

Triiodothyronine antibodies in patients with goiter.

OBJECTIVE To investigate the prevalence of triiodothyronine (T(3)) antibodies in patients with goiter, the influence of these antibodies on the results of thyroid hormone measurements, and the potential relationship between T(3) antibodies and thyroid autoantibodies. METHODS We undertook a study of 100 healthy control subjects (80 female and 20 male subjects) who had no clinical or biochemical evidence of thyroid disease and 100 patients (81 female and 19 male patients) with goiter. Serum concentrations of total T(3), total thyroxine, free T(3), and free thyroxine were measured by radioimmunoassay kits with a coated tube method. An immunoprecipitation method was used to detect anti-triiodothyronine auto-antibodies. RESULTS Patients with a T(3) antibody binding ratio +3 standard deviations (SD) above the mean for the normal control group were considered to have T(3) antibodies. Normal control group binding was 2.4 +/- 1.3%. On the basis of +3 SD, seven patients had T(3) antibodies. The mean serum total T(3) level was 1.61 +/- 0.1 nmol/L in patients with binding ratios above +3 SD, whereas the mean serum total T(3) level was 2.23 +/- 0.3 nmol/L in patients without T(3) antibodies. Thus, patients with a binding ratio above +3 SD had a significant decrement in total T(3) levels. No correlation was found between the presence of T(3) antibody and antimicrosomal and antithyroglobulin antibodies. CONCLUSION When serum thyroid hormone concentrations are measured with a coated tube-radioimmunoassay method, antibodies can result in low T(3) concentrations. T(3) antibodies should be suspected whenever a discordance is noted between the measured thyroid hormone concentrations and the clinical status.

Acarbose treatment in obesity: a controlled study

Acarbose is an alpha-glucosidase inhibitor which reversibly inhibits oligosac charidase and disaccharidase at the brush border of the small intestine. The aim of this study was to observe its effectiveness in the treatment of obesity. Methods: Two groups o 25 obese women were put on a 15 kcal/kg/day low-calorie diet for 12 weeks. One group (the study group) received 150 mg/day acarbose for the first 2 weeks and 300 mg/day acarbose for the remaining 10 weeks. The second group (controls) received no additional treatment. Body weight, BMI, skinfold thickness, serum lipids, OGTT, and insulin and C-peptide responses to OGTT were assessed before and after the study. Results: Body weight, BM and skinfold thickness decreased significantly in both groups. Basal insulin and triglyceride levels in the study group, total and LDL cholesterol and triglyceride levels in the contro group decreased significantly. No difference was found between the two groups when these decrements were compared, but the triglyceride level fell more in the control group Conclusion: Additional acarbose therapy is not more beneficial than low-calorie diet therapy alone.

Small Cell Neuroendocrine Carcinoma of the Thymus Complicated by Cushing's Syndrome: Report of a 58-year-old Woman with a 3-year History of Hypertension

A 58-year-old woman with a history of Cushings syndrome for three years presented with a mediastinal mass and received the diagnosis of small cell neuroendocrine carcinoma of the thymus invading the pericardium. On immunohistochemical study, the neoplastic cells reacted with antibodies against cytokeratin, epithelial membrane antigen, neuron-specific enolase, chromogranin, synaptophysin, and ACTH. Clinicopathologic findings of this rare case of ectopic adrenocorticotropic hormone (ACTH) syndrome are discussed with a literature review.