<prompt> Which of the following tests is not used in the diagnosis of insulinomaFasting blood glucoseXylose testC- peptide levelsInsulin Glucose Ratio  <response>: Answer is B Xylose test : Xylose test is used in the diagnosis of malabsorption due to intestinal mucosal disease. This test is not used for the diagnosis of Insulinomas Fasting blood glucose, C- peptide levels and Insulin Glucose Ratio are all used in the diagnosis of Insulinomas. Diagnosis of Insulinomas 6,uUm1 when blood glucose in 40 mgdl alignleft height40 width237Serum insulin levels fasting Serum glucose levels fasting Serum C- peptide levels Elevated Serum proinsulin levels Elevated Insulin Glucose Ratio 0.3 Plasma fl-Hydroxybulyrate Decreased The most reliable test is a fast upto 72 hours with serum glucose, C-peptide and insulin levels measurements every 4-8 hours 