Diabetes is characterized by elevated blood sugar levels due to abnormalities of insulin production by the pancreas and abnormal insulin function, or both. The adverse effects of chronic high blood sugar render diabetes the most common cause of end-stage kidney disease and often result in blindness, nerve damage, circulation problems and heart and cerebrovascular disease. The diagnosis and management of diabetes relies on laboratory testing of its associated effects in the blood.
Hyperglycemia
The diagnosis of diabetes requires laboratory testing for hyperglycemia, or elevated blood sugar, the characteristic effect on the blood of every type of diabetes. Normally, the glucose concentration in the blood varies between 70 and 120 mg/dL. The criteria used to diagnose diabetes include fasting blood glucose levels greater than 126 mg/dL on at least two occasions, non-fasting plasma glucose levels greater than 200 mg/dL with clinical symptoms or oral glucose tolerance test results with elevated blood glucose levels two hours following the start of the test.
Levels of blood glucose higher than expected, but less than those diagnostic of diabetes, may indicate impaired fasting glucose or impaired glucose tolerance, known as pre-diabetes. Some, but not all, pre-diabetic patients with abnormal blood glucose levels eventual meeting diagnostic criteria for diabetes.
Ketoacidosis
A serious and potentially deadly condition involving the blood in diabetic patients, diabetic ketoacidosis (DKA) occurs with extremely high levels of glucose circulating in the blood, according to the American Diabetes Association. These high levels make the sugar unavailable as an energy supply inside the cells of the body. As a result, the body’s cells start burning fat for energy rather than glucose, leading to the production and accumulation of toxic substances known as ketones.
High levels of ketones circulating in the blood of diabetic patients can poison the body, resulting in coma and death. Evaluation of the blood for ketones and other blood components called electrolytes facilitates the diagnosis of DKA, allowing for rapid treatment necessary to save a patient’s life.
Hyperlipidemia
Elevated cholesterol and lipid levels in the blood are commonly associated with hyperglycemia, insulin resistance and diabetes. While elevated lipids are present in patients without diabetes, patients with diabetes have a heightened risk for this blood disorder, increasing their already high risk for atherosclerosis, cardiovascular disease and cerebrovascular disease.
Evaluation of lipids, including triglycerides and cholesterol in the blood, provides for an important component in the monitoring and treatment of diabetes. According to the Centers for Disease Control, regulation of low-density lipoproteins, or LDL cholesterol, circulating in the blood may decrease the morbidity and mortality of atherosclerosis and its effects in the diabetic patient, reducing heart and blood vessel disease complications by as much as 50 percent.
