Gestational Diabetes Mellitus is defined as glucose intolerance diagnosed during pregnancy.
It is recommended that pregnant women with any risk factors be screened at the first prenatal visit. For women at high risk not found to have GDM at the first visit, repeat testing is indicated between 24 and 28 weeks.
If 2 or more values are abnormal then the patient has a positive diagnosis of gestational diabetes.
It has been found that women diagnosed with gestational diabetes already have insulin resistance at baseline with a higher level of plasma insulin levels. Women diagnosed with GDM need training about daily self monitoring of glucose 6-7 times a day with a minimum of 4 times. All women diagnosed with GDM require nutritional counseling for the appropriate amount of weight gain during pregnancy as well as dietary control.
It is a critical point in time for changing the lifestyles of these women since they are at a high risk for development of type 2 diabetes. The use of oral medications is considered when diet and exercise do not adequately control blood sugars. Some studies have recently evaluated the safety and efficacy of Glyburide [sulphonylurea] after the first trimester for treatment of GDM. There is inadequate data in regards to the safety and efficacy of other oral antidiabetic medications such as Metformin, thiazolidinediones and Acarbose.
The diagnosis and treatment of gestational diabetes is critical because elevated blood sugars adversely affect both the mother and the baby. Approximately 50% women will develop type 2 diabetes within 5 years of development of gestational diabetes. The first consideration is to rule out a fasting hypoglycemia, especially when hypoglycemic symptoms occur several hours after food intake. Unfortunately, diagnosis has not been as simple as the classic OGTT findings just mentioned would imply. In summary, the diagnosis of postprandial hypoglycemia is clouded by controversy, especially the category of functional hypoglycemia. Pituitary adenylate cyclase–activating polypeptide (PACAP) is a ubiquitous neuropeptide of the vasoactive intestinal peptide (VIP) family that potentiates glucose-stimulated insulin secretion. Aah…the aroma of fresh baked cookies, there is nothing like it to bring back fond memories! Every Sunday afternoon right after dinner my Mom and Dad would load us kids up in the car & head over to visit my grandparents. With out fail Granny as we fondly called her, would make her way to the kitchen and start a pot of coffee. These icons link to social bookmarking sites where readers can share and discover new web pages. The program has been talked about in several circles and is just now doing a slow roll out of the entire program, so this would be a great time to get in on the ground floor.
Now that I am older, I wonder if it was the cookies or the conversation that made the memory so special.
Discuss various statistics regarding diabetes mellitus, including its prevalence in the United States.
Differentiate between type 1 and type 2 diabetes, including pathogenesis and prevalence for each type. List and explain the various tests and methodologies used for the identification of diabetes.
Discuss various features of hemoglobin A1c and other glycated proteins, including fructosamine and glycoalbumin and their use in the detection of diabetes.
Explain long-term monitoring of diabetes mellitus, including the use of estimated average glucose. Although simply defined on the basis of hyperglycemia, diabetes mellitus today is known to be a highly heterogeneous disease. In the past, the diagnosis of diabetes was based on either fasting plasma glucose or two-hour plasma glucose level in the oral glucose [75 g] tolerance test (OGTT). The glycation of hemoglobin occurs at several amino acid residues and, as a result, several adducts of hemoglobin A (HbA) and various sugars are formed by the nonenzymatic post-translational glycation process. Various methods for the measurement of HbA1c have been described and reviewed.6 These methods can be classified in two major categories. Because of their ability to process a large number of samples and their superior precision, automated HPLC and automated immunoassays are among the most widely used methods. Besides the standardization of various methods, one may also be aware of the clinical situations in which HbA1c may not provide an accurate estimation of glycemic control. Several assays designed to measure glycated serum proteins (fructosamine and GA) have been described.
Despite these limitations, measuring fructosamine or GA provides some advantages over measuring glycohemoglobin A1c as they are not affected by RBC life span, and the glycated protein levels respond more quickly to changes in glycemic control than glycohemoglobin A1c. The effective clinical management of diabetes requires accurate measurement and monitoring of blood glucose levels. Several studies have explored the relationship between HbA1c and chronic glycemia and have supported the association of HbA1c with average glucose levels over the preceding five to 12 weeks.17 These studies have relied on infrequent measures of capillary glucose levels, calling into question the validity of their assessment of chronic glycemia. Recently, HbA1c has been incorporated into diabetes diagnosis, and is recommended by the International Expert Committee based on advances in instrumentation and standardization that make it an accurate and precise marker. International expert committee report on the role of the A1c assay in the diagnosis of diabetes. This could either be newly diagnosed type 1 or type 2 Diabetes Mellitus or this could be a new onset of hyperglycemia secondary to metabolic changes related to pregnancy.
One can either take a two step approach, starting with the 50 gm glucose challenge test, followed by an oral glucose tolerance test if the results of the former test are abnormal.
During the early part of pregnancy there is increase in insulin secretion and beta cell hyperplasia. It is recommended that pregnant women exercise for about 20-30 minutes everyday or at least most days of the week. The older sulphonylureas were not recommended for use in pregnancy because they crossed the placenta. The fetus is at increased risk of macrosomia, hypoglycemia, hypocalcemia, hypomagnesaemia, jaundice, polycythemia, respiratory complications, congenital malformations and fetal loss including abortion, still births and neonatal deaths. The greatest risk factor for early-onset type 2 diabetes after pregnancy was early gestational age at the time of diagnosis and elevated fasting glucose. Postprandial Hypoglycemia of gastrointestinal tract origin (sometimes called the “dumping syndrome”) most often occurs after gastric surgery and results from unusually swift or complete gastric emptying of ingested carbohydrate into the duodenum, resulting in abnormally high blood glucose levels and temporary hypoglycemia after hastily produced insulin has overcome the initial hyperglycemia. Some persons with subclinical or early diabetes mellitus of the NDDG type II (noninsulin-dependent) category may develop mild and transitory hypoglycemia 3-5 hours after eating. A few patients with insulinoma or alcoholism may develop postprandial hypoglycemia, although fasting hypoglycemia is much more common.


Self-administered hypoglycemic agents are also possible, although for some reason this is not often mentioned when associated with postprandial symptoms. Many investigators have found disturbing variability in OGTT curves, which often change when testing is repeated over a period of time and may change when testing is repeated on a day-to-day basis. Pancreatic ? cells express two PACAP receptor subtypes, a PACAP-preferring (PAC1) and a VIP-shared (VPAC2) receptor. Recently, the International Expert Committee (2009) and the ADA Clinical Practice Guidelines (just published in 2013) recommended the use of glycated hemoglobin (HbA1c) to diagnose diabetes.2-3 This article will review the current state of the laboratory testing with special focus on the role of  HbA1c and other emerging glycated protein biomarkers, including fructosamine and glycated albumin (GA), in the diagnosis and long-term monitoring of diabetes. For decades the diagnosis of diabetes mellitus (type 1 and type 2) was made on the basis of an elevated fasting glucose level. Furthermore, in spite of standardization, many factors, including noncompliance for fasting and inability to tolerate the glucose load, among many other factors, influence the final test outcome. Glycemic biomarkers are important tools to monitor glycemic control.5 Measurement of glycated proteins, primarily HbA1c, has been widely used for routine long-term monitoring of glucose control and as a measure of risk for the development of diabetes complications. Hemoglobin A1c was first discovered in 1969 as an abnormal hemoglobin fraction in blood from diabetes patients. This process involves the formation of a labile Schiff base intermediate followed by the Amadori rearrangement. One category is based on separation and detection of HbA1c on the basis of charge differences and includes ion-exchange chromatography, high performance liquid chromatography (HPLC), and agar gel electrophoresis. Glycation of HbA1c not only depends on average glycemia but also on the rate of production or destruction of RBCs. Like glycohemoglobin, glucose molecules are joined to protein molecules through a nonenzymatic glycation mechanism to form stable ketoamines termed fructosamine.
However, these assays are currently used only to complement glycohemoglobin A1c assays to manage diabetic patients when the detection of short-term metabolic changes is required. Traditionally, plasma glucose has been the lab test used for monitoring the patient with diabetes. More recently, an international multicenter study examined the relationship between average glucose, as assessed with a combination of continuous glucose monitoring and frequent finger-stick capillary glucose testing and HbA1c levels over time, and demonstrated a close relationship between the two. Currently HbA1c is widely used as a glycemic marker for long-term monitoring of diabetes, as it provides valuable information about the degree of glucose control during the previous eight to 12 weeks.
Repeatability of the oral glucose tolerance test for the diagnosis of impaired glucose tolerance and diabetes mellitus. Effects of hemoglobin variants and chemically modified derivatives on assays for glycohemoglobin. Defining the relationship between plasma glucose and HbA1c in the Diabetes Control and Complications Trial.
This leads to an increase in insulin sensitivity with low fasting blood sugar levels, increased glucose uptake by peripheral tissue and glycogen storage as well as decreased hepatic gluconeogenesis. The pancreas however, is unable to cope with this additional stress of elevated level of insulin resistance. Testing for the presence of ketones in a fasting urine sample is a valuable tool to assess the adequacy of caloric intake in these patients. These patients should restrict fat intake and substitute simple or refined sugars in their diet to more complex carbohydrates.
This seems to be an early manifestation of their disease, which often disappears as the disease progresses. The best test would be a blood glucose measurement drawn at the same time that symptoms were present.
In some cases this is related to factors known to influence the OGTT, such as inadequate carbohydrate preparation, but in other cases there is no obvious cause for OGTT discrepancies. Quickly we were all gathered around the Kitchen table sharing cookies, milk or coffee and great conversation. Type 1 diabetes is characterized by absolute insulin deficiency due to autoimmunity leading to ?-cell destruction and can be identified by serological markers of autoimmunity (islet cell autoantibodies). The ADA proposes that fasting plasma glucose (FPG) should be measured in all asymptomatic people ?45 years of age and screening should be considered at a younger age in individuals at increased risk for diabetes.
Based on current recommendations from the National Diabetes Data Group, the OGTT must be done after three days on a diet containing a minimum of 150 g of carbohydrates per day. The test accurately assesses the mean blood glucose level during the preceding two to three months; therefore, it complements the more traditional measures of glucose control (blood or urine glucose testing). It was later shown that glucose binds to hemoglobin in red blood cells, and the term “glycohemoglobin” is applied to a number of chemically distinct hemoglobin components that are generated when glucose binds to hemoglobin.
The reaction is slow, continuous, and irreversible, and the reaction rate depends on the ambient glucose concentration. There is no convincing data to show that one method is superior to the other, as practically all commercial methods are standardized to a common reference standard.
Findings from the Diabetes Control and Complication Trial demonstrate that maintaining blood glucose close to normal reduces diabetes complications.17 This study compared the standard versus intensive blood glucose control on the complications of diabetes. It is also being used as a primary treatment target, as it has been shown to have close association with diabetes complications. However, it should be reiterated that there are some limitations, and HbA1c may not provide accurate information in certain clinical situations that affect RBC life span—for example, certain hemoglobulinopathies (hemoglobin S, C, or E), anemia, and renal dysfunction. This process is crucial for the build-up of maternal adipose tissue, to be used in the later part of pregnancy.
Positive urine for ketones indicates a state of starvation and the patients should be advised to increase their daily caloric consumption. There isn’t enough data regarding the safety of the long acting insulin glargine in pregnancy. It has been shown that it is as effective as insulin, more cost effective than insulin and safe for use in pregnancy. Women with normal pregravid glucose tolerance who develop gestational diabetes in late gestation have no increased risk of fetal congenital anomalies beyond the population risk for women with normal glucose metabolism. In some cases symptoms can be correlated with acceptably low blood glucose values, in which case many physicians make a diagnosis of functional hypoglycemia (although there is controversy on this point, to be discussed later with the 5-hour OGTT).
Because symptoms in daily life usually occur at times when blood specimens cannot be obtained, the traditional laboratory procedure in postprandial hypoglycemia has been the 5-hour OGTT. Another major problem is disagreement regarding what postprandial blood glucose value to accept as indicative of hypoglycemia. We talked about everything from the price of cattle to who won the spelling bee at school that week.
The three-to-five hour oral glucose tolerance test, once the gold standard for diagnosing diabetes, is currently not recommended either by the ADA or the International Expert Committee.2-3 However, both the ADA and International Expert Committee continue to recommend use of the two-hour oral glucose challenge test, especially in gestational diabetes mellitus (GDM). The clinical utility of insulin measurement is limited, primarily because when fasting glucose is elevated, ?-cell responsiveness decreases, and when the fasting glucose level is normal, late hyperinsulinism may occur in type 2 diabetes or in the early phase of type 1 diabetes. In addition to hemoglobin, other proteins in blood can also be glycated, and glycated proteins such as fructosamine and glycoalbumin (GA) can also be measured and used as an estimation of glucose control.5 Today the use of HbA1c is also recommended by the ADA and other organizations for diabetes screening and diagnosis. Minor components of HbA were first recognized because of the differences in their electrical charges and were called “fast hemoglobin” as they migrated at a faster rate than an entire HbA molecule when placed in an electrical field.


Albumin is the most abundant serum protein, and it contains multiple lysine residues, all of which can be glycated. There are clinical situations in which fructosamine or GA should not be used, such as for thyroid disease (as in thyrotoxic or hypothyroid patients in whom protein turnover is increased or decreased).
Now HbA1c levels can be expressed and reported as eAG for most patients with type 1 or type 2 diabetes. Furthermore, its value can be translated into eAG values, providing valuable information to clinicians in monitoring patients with diabetes. If a discrepancy between blood glucose and HbA1c is observed, one must consider the measurement of extracellular glycated proteins (fructosamine or GA), as these are not affected by RBC life span or iron status.
During the late phase, there is an increase in hormones such as cortisol, prolactin, progesterone and human placental lactogen which leads to a state of relative insulin resistance, possibly via a post receptor defect in the cells.
Both American Diabetic Association [ADA] and American college of Obstetricians and Gynecologists [ACOG] await more research related to the effect of glyburide on maternal and perinatal outcomes before approving its use. The children of women diagnosed with GDM are at increased risk of obesity and abnormal glucose metabolism during childhood, adolescence and adulthood. However, because of the large number of diabetic persons, it may be a relatively frequent cause of postprandial hypoglycemia.
In other cases, probably the majority, symptoms cannot be adequately correlated with acceptably low blood glucose values. In alimentary hypoglycemia the classic OGTT pattern is a peak value within 1 hour that is above OGTT reference limits, followed by a swift fall to hypoglycemic levels (usually between 1 and 3 hours after glucose). Today, diabetes-associated complications remain the leading cause of heart disease- or stroke-related deaths and are associated with long-term damage including the failure of organs such as eyes and kidneys. Type 2 diabetes is caused by insulin resistance and lack of compensatory insulin secretory response. However, it has some limitations, indicating the need for the use of other glycated protein biomarkers. Also, HbA1c levels can be false high in situations that increase the production of RBCs, as in patients with chronic kidney disease who receive erythropoietin for anemia or in patients who receive a blood transfusion.11 In brief, HbA1c levels are shown to be positively associated with hemoglobin levels and are negatively associated with erythropoietin dose. Levels are also influenced by low albumin levels, as seen in patients with protein-losing enteropathy, nephritic syndrome, or liver failure. Today, use of HbA1c is accepted as a long-term monitoring tool for the management of diabetic patients and is used in conjunction with plasma or finger-stick glucose testing.
The calculated eAG level gives healthcare providers a more useful index of chronic glycemia. However, their relationship to average glucose and their prognostic value to diabetes complications are not clear, as in the case of HbA1c.
Women diagnosed with gestational diabetes are at increased risk of gestational hypertension including preecclempsia, caesarian section and assisted deliveries. One of the mechanisms thought to be contributing to the long term complications in these babies is ‘early onset hyperinsulinimia’.
Initial elevation of blood glucose values may or may not be higher than in normal persons, but the 2-hour postprandial value is elevated. Either the OGTT serum glucose value is low but no symptoms occur, or (less commonly) symptoms occur at a relatively normal glucose level. In diabetic hypoglycemia, there is an elevated 2-hour postprandial value, followed by hypoglycemia during the 3-5 hours postglucose time interval. In vivo, the insulinotropic action of PACAP was also acutely reduced, and the peptide induced impairment of glucose tolerance after an intravenous glucose injection.
In contrast to type 1 diabetes, type 2 diabetes is highly prevalent and accounts for 90% to 95% of all diabetes cases. The most important HbA component in diabetes is HbA1c, which has glucose attached at the N-terminal-amino groups of both ? chains of hemoglobin. Just like glycohemoglobin, fructosamine and GA measurements serve as an index of the mean concentration of glucose in the blood during the preceding several weeks. Portable glucose meters are routinely used either in physician offices or by patients at home. The rise in plasma insulin after eating tends to be delayed, and the insulin peak (when finally achieved) may be somewhat elevated, resulting in the hypoglycemic episode.
In functional hypoglycemia, there is a normal OGTT peak and 2-hour level, followed by hypoglycemia during the 2 to 4-hour postglucose time interval (Fig.). In some cases it is not clear whether serum or whole blood was assayed (reference values for whole blood are 15% less than those for serum or plasma).
This demonstrates that PAC1 receptor is involved in the insulinotropic action of the peptide. However, because of rapid turnover of serum proteins compared to hemoglobin, the fructosamine and GA levels reflect glucose control over a shorter period of two to three weeks rather than six to 10 weeks for glycohemoglobin. The current recommendation, therefore, is to normalize fructosamine results to a given serum albumin or total protein concentration. Day-to-day management as guided by self-monitoring of blood glucose by patients with the use of glucose meters is a common practice today. An additional problem involves the concept of chemical hypoglycemia versus clinical hypoglycemia.
Also, with a colorimetric analysis, bilirubin, hemolysis, and lipemia will likely interfere in the measurement.
A number of studies have shown that a certain percentage of clinically normal persons may have OGTT curves compatible with functional hypoglycemia without developing any symptoms.
The defective insulinotropic action of glucose was associated with marked glucose intolerance after both intravenous and gastric glucose administration. Thus, these results are consistent with a physiological role for the PAC1 receptor in glucose homeostasis, notably during food intake. Moreover, in some studies continuous blood glucose monitoring systems disclosed hypoglycemic dips not evident in standard OGTT specimens. On the other hand, some persons with symptoms compatible with hypoglycemia do not develop OGTT values below reference limits. To make matters more confusing, some studies have found that when the 5-hour OGTT was repeated after it had initially displayed a hypoglycemic dip, a substantial number of the repeat OGTT results became normal (about 65% of cases in one report). Finally, several studies have indicated that hypoglycemic values found during an OGTT usually disappear when an ordinary meal is substituted for the carbohydrate dose.
Since actual patients do not usually ingest pure carbohydrate meals, this casts doubt on the reliability and usefulness of the OGTT in the diagnosis of functional hypoglycemia.



Low blood sugar scale
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Hypoglycemia treatment medicine 5th
Average fasting blood glucose level low


Comments

  1. 15.07.2014 at 20:29:45


    Glycated hebmologin test, isn't free to take some coffee testing of your blood sugar is important.

    Author: QaQaSh_099
  2. 15.07.2014 at 16:58:19


    Will depend on the levels evaluate your blood glucose levels, carry.

    Author: Ubicha_666