Glycosylated Hemoglobin: HgA1c
Glycosylated hemoglobin is formed by the irreversible, non-enzymatic binding of circulating glucose to the amino groups of lysine and valine residues in hemoglobin. It is measured as a ratio of glycosylated hemoglobin to non-glycosylated hemoglobin. The level of HgA1c in erythrocytes depends on the concentration of glucose in blood. When level of blood glucose is high, the rate of glycation is increased, hence more glycosylated hemoglobin. Glycation occurs slowly and over the entire lifespan of the red blood cell, i.e. 90-120 days. Therefore, HbA1c reflects the average level of blood glucose exposed to the red blood cell over the past 3-4 months. The measurement of HbA1c is used as an index of mean blood glucose in the treatment of patients with diabetes mellitus. The normal range of HbA1c in healthy persons is 4-5.9%. The diagnosis of diabetes can be made when the HbA1c level is greater than 6.5%. Levels just below 6.5% may indicate immediate hyperglycemia. Although the precise lower cut off point for this has not been determined, the high risk range was suggested to be 5.7%-6.4%. Patients with measurements between 6.0% and 6.5% are particularly at high risk and should consider interventions for diabetes prevention.
Antibiotic associated colitis is an inflammation of the colon, which results from the disruption of normal bacterial flora in the large intestine, after the intake of antibiotics. The antibiotic eliminates most bacteria in the large intestine reducing competition. The remaining bacteria face less competition for nutrients and space and, therefore, thrive. An example is Clostridium difficile, which proliferates in the bowel and produces toxins A and B. These toxins are responsible for the mucosal damage and the inflammation of the colon. Without the toxins, Clostridium difficile may colonize the large intestine without causing damage to the colon. The use of antibiotics such as clindamycin, cephalosporins and amoxicillin, results in the alteration of normal bacterial flora in the large intestine. Symptoms normally begin to show 4 to 10 days after the administration of antibiotics. The symptoms include watery diarrhea, lower abdominal pain and loose stool. The progression of the disease may lead to fatigue and fever. The disease may proceed to pseudomembranous colitis where the patient may experience nausea, watery diarrhea and vomiting. Hospitalized patients are at a higher risk of catching the infection. In addition, the disease is more common among the elderly than in young people. The treatment involves stopping the administration of the antibiotic that caused the disease. This allows for the repopulation of the normal bacterial flora in the large intestine. The patient should also take more fluids to prevent dehydration.
Heat exhaustion is a form of heat-related illness, which can occur after a long exposure to high temperatures and inadequate replacement of fluids. The high air temperature and relative humidity hinders the evaporation of sweat and the ability of the body to cool itself. The people at high risk of developing heat exhaustion are the elderly, those with high blood pressure, and workers in hot environments. The symptoms of heat exhaustion include dizziness, heavy sweating, headache, nausea, vomiting, ataxia, paleness, muscle cramps and general weakness. The skin is often moist and cool. The pulse rate of the victim will be fast and weak and his breathing fast and shallow. Cooling measures may be effective in the treatment of heat exhaustion. These include intake of cool beverages, cool bath, air conditioned environment, rest and removing tight clothing.
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Sikaris , K. (2009). The Correlation of Hemoglobin A1c to Blood Glucose. Journal of Diabetes Science and Technology, 429-438.