Diagnostic Approach

Overview:

Diagnosing hyperglycemia in hospitalized patients involves a multi-faceted approach that includes clinical assessment, laboratory tests, and continuous monitoring. This is crucial for distinguishing between stress-induced hyperglycemia and pre-existing diabetes, and for tailoring a management plan accordingly.

Initial Assessment:

Upon presentation, it’s essential to perform a thorough clinical evaluation, reviewing the patient’s medical history, current medications, and symptoms. This sets the stage for subsequent diagnostic tests.

Laboratory Tests:

• Blood Glucose Levels: A fasting blood glucose level greater than 126 mg/dL or a random blood glucose level greater than 200 mg/dL is indicative of hyperglycemia.
• HbA1c Test: This test provides a longer-term view of blood sugar control. An HbA1c level above 6.5% is generally considered diagnostic for diabetes.
• Blood Ketones: Particularly relevant in potential cases of diabetic ketoacidosis (DKA).

Monitoring:

• Continuous Glucose Monitoring (CGM): Particularly useful in critically ill patients or those with fluctuating glucose levels.
• Point-of-Care Testing: Quick fingerstick tests can be useful for immediate assessment but should be confirmed with more accurate laboratory tests.

Special Tests:

• C-Peptide Test: Useful in distinguishing between Type 1 and Type 2 diabetes by measuring endogenous insulin production.
• Oral Glucose Tolerance Test (OGTT): Rarely done in hospitalized settings but may be considered in specific cases.