Avoiding Glucose Monitoring Errors

Avoiding Glucose Monitoring Errors in Patients Receiving Other Sugars (February 2006) This story originally aired in February 2006. In this Special Edition of PSN, we are repeating some of the most important safety issues that continue to pose a public health problem. FDA issued a reminder about the potential for falsely elevated glucose readings in patients who are also receiving products that contain other sugars. These products include oral xylose, parenterals that contain maltose or galactose, and peritoneal dialysis solutions that contain icodextrin. Several patients have died because of this problem. Their glucose readings were very high, so they were given aggressive insulin treatment. The glucose readings were falsely high, however, and too much insulin was administered. The patients suffered hypoglycemic shock or irreversible brain damage and died. In these cases, the glucose meter was reading the patient's actual blood glucose level, plus the maltose that was contained in the IV immune globulin he was receiving. The readings were falsely elevated because the glucose monitoring device couldn't distinguish between glucose and other sugars. All glucose meters don't suffer from this problem. There are several kinds of enzymatic glucose monitoring methods that are used, and only one of those has this problem. This problem occurs only with the monitoring method that uses an enzyme called GDH-PQQ. This method is employed in some glucose monitoring devices used by diabetics at home and in point-of-care settings. The other methods currently used in glucose monitoring systems are called GDH-NAD, GDH-FAD, glucose oxidase, and glucose hexokinase, and they are capable of distinguishing between glucose and other sugars. The test method used in glucose meters is identified in the package insert that comes with the glucose test strips. The package insert is also available from the manufacturer. The most important thing to remember is not to use the GDH-PQQ method if the patient recently received other sugars. That includes oral xylose for a D-Xylose absorption test, or an IV solution containing maltose or galactose, or a peritoneal dialysis solution containing icodextrin.