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What is Diabetes mellitis diagnosed when - and explain in detail?
Criteria for the diagnosis of Diabetes mellitus : * Symptoms of diabetes plus random blood glucose concentration >=11.1 mmol/L (200 mg/dL)a or * Fasting plasma glucose >=7.0 mmol/L (126 mg/dL)b or * Hemoglobin A1c >= 6.5%c or * 2-h plasma glucose >= 11.1 mmol/L (200 mg/dL) during an oral glucose tolerance test Reference : page 2401 Harrison's Principles of Internal Medicine 19th edition