Diabetes diagnosis (part2)

Diagnostic criteria: the majority of the use of the current proposed 1985 WHO provisional standard as follows:

⑴ diabetes symptoms, at any time venous plasma glucose ≥ 200mg/dl (11.1mmol / L) and fasting venous plasma glucose ≥ 140mg/dl (7.8mmol / L) can be diagnosed as diabetes.

If the result ⑵ suspicious, should be carried out OGTT (oral glucose adults 75g), per kg body weight of children 1.75g, total no more than 75g), 2 hPG ≥ 200mg/dl (11.1mmol / L) can be diagnosed as diabetes. Blood glucose> 140mg/dl ~ <200mg/dl for impaired glucose tolerance (TGT).

⑶ symptoms such as non-diabetic, with the exception of these two diagnostic criteria, the indicators need to be a plus to help diagnosis, OGTT curve in the 1 ° or 2 ° blood glucose ≥ 200mg/dl or another fasting blood glucose ≥ 140mg/dl.

⑷ gestational diabetes diagnostic criteria can be used to this.

Diagnosis of diabetes should be the exception of the impact of fashion tolerance of a variety of factors, including the anterior pituitary, adrenal cortex, endocrine diseases such as hyperthyroidism, obesity, liver disease, a variety of drugs (such as Thiazide diuretics, female contraceptives, glucocorticoids hormones, phenytoin, p-A thiadiazines, etc.), stress (such as fever, infection, acute myocardial infarction, surgery, etc.), loss of potassium.

2. Determination of blood glucose 2h after a meal to eat the equivalent of 100g of sugar glucose steamed food such as rice, such as 2, after two or 2h glucose, such as more than 140mg/dl were reduced tolerance, ≥ 200mg/dl for diabetes.

As a result of sugar starvation diet or impaired glucose tolerance can, therefore try to adjust before the 3d should be noted that feeding carbohydrate diet so that not less than 250g / d, in order to obtain reliable results.

Some patients to take an estimate of the β-cell function or status of glycemic control, can make the following determination:

1. Determination of fasting plasma insulin in our hospital measured by radioimmunoassay in fasting plasma insulin and normal range of 5 ~ 20μu/ml, Ⅰ-type patients following 5μu/ml often, sometimes as low as not measured. Type Ⅱ patients with normal plasma insulin concentration, a small number of those who have low, often higher than normal in obese patients, who showed significantly increased hyperinsulinemia, suggesting that there is insulin resistance. For the metabolic syndrome in which a component can be considered a risk factor for coronary heart disease in recent years concern. Insulin and insulin-immune cross-cutting nature of the original, it can be for the general radioimmunoassay method to measure, but the adverse cardiovascular effects of proinsulin on insulin and may even be worse. Research has been applied to the determination of proinsulin clinical.

2. Insulin release test in the oral glucose tolerance test conducted at the same time when the determination of plasma insulin concentration to reflect the function of pancreatic β-cell reserve. In addition to type Ⅰ patients fasting level is very low, the glucose-stimulated insulin levels are still low, flat curve was low, especially at the same time calculation of the glucose (G) and insulin (IRI) ratio, (IRI) / G, prompt insulin secretion low (normal for 25μu/mg). Fasting patients with type Ⅱ normal or high level, stimulated the release was delayed. After the glucose-stimulated insulin without a marked increase in the water or the low, suggesting that the lower β-cell function.

3.C peptide release from pancreatic β-cells after insulin by the liver and kidney enzymes by insulin can eliminate, in the peripheral blood of each cycle will be 80 percent destroyed, and its half-life of only 4.8 minutes, the blood concentration of only on behalf of its secretion of a very small portion of the total. Department of C-peptide and insulin from proinsulin split into categories of objects, such as peptides, enzymes from the liver can eliminate only the role of the excretion by the kidneys and its half-life of 10 to 11 minutes, the blood concentration can be more better reflect the function of pancreatic β-cell reserve. Determination of C-peptide without the interference of insulin antibodies, and determination of non-insulin cross-immune response, but also free from the impact of insulin injections, it has been used in recent years, measured the blood concentration of C-peptide or 24-hour urine excretion to reflect the β-cell secretion function.

⑴ Determination of serum C-peptide concentration: 2 immunization using radioimmunoassay method when the normal fasting serum C-peptide was 1.0 ± 0.23mg/dl, when oral glucose peak after 60 minutes to see when the concentration of 3.1ng / ml, measured according to Block, etc. , 100g oral glucose in normal serum C-peptide from 1.3 ± 0.3ng/ml at 60 minutes rose to 4.4 ± 0.8ng/ml, Ⅱ type diabetes rose by only two hours after 2.3ng/ml. Another five cases had type Ⅰ patients to rule for more than 5 years of insulin C-peptide levels were very low, both when fasting and after stimulation have not been measured.

⑵ 24-hour urine C-peptide determination: normal 24-hour urine C-peptide was 36 ± 4μg, Ⅰ-type patients only 1.1 ± 0.5μg, Ⅱ-type patients who were 24 ± 7μg, daily C-peptide of insulin secretion from the equivalent of about the amount of 5%, while insulin output accounted for only 0.1%.

Determination of the above-mentioned C-peptide to insulin administration in type Ⅰ way patients can be identified β-cell function, at present, not only for scientific research, often using clinical.

Determination of 4.HbA1c normal fasting blood glucose and blood glucose fluctuations may reflect the greater recent blood sugar 2 to 3 months, the normal HbA1c6%, HbA1 for 8%, diabetes often are higher than normal.

5. Fructosamine Fructosamine normal serum 2.13 ± 0.24mmol / L (plasma low-0.3mmol / L), can reflect the nearly 1 ~ 4 weeks in the case of blood glucose, and HbA1c parallel, regardless of diabetes type Ⅰ, Ⅱ-type have increased, particularly for the high type Ⅰ.

In short, diagnosis of diabetes can be the root of history, clinical manifestations, combined with the above-mentioned urine sugar, blood glucose and OGTT identified. In addition, it has yet to identify a variety of complications and associated disorders, and the estimation of their severity, type, stage of development and function of major organs such as the treatment of this disease and the prognosis is very important.