Urine glucose testing: reliable backup for whole blood glucose monitoring

Urine glucose testing has been deemed by some to be nonessential in the management of diabetes mellitus since the technique and equipment for self-monitoring of blood glucose has become available. However, most physicians have experienced pitfalls in the management of diabetes mellitus when insulin dosage is adjusted daily based solely on the patient's monitoring of blood glucose. There have also been recent reports suggesting the use of urine glucose testing as a reliable and a reasonable alternative to monitoring of blood glucose in the management of diabetic subjects, including those using insulin as the mode of therapy. In this report, we describe a patient in whom diabetic ketoacidosis occurred during hospitalization as a result of inadequate insulin administration due to inaccurate capillary blood glucose test results. Furthermore, urine glucose and ketone values obtained simultaneously had been disregarded. If insulin therapy had been adjusted according to urine glucose results rather than blood glucose readings, diabetic ketoacidosis could have been averted in this patient. Urine glucose testing may provide a reliable backup for suspect whole blood glucose values and may prevent catastrophic events requiring expensive hospitalization. This report also delineates several potential procedural problems that exist in the technique of whole blood glucose monitoring and provides recommendations to overcome these deficiencies.