In recent years advances have occurred in understanding the fundamental mechanisms associated with Alzheimer’s disease.1 However, despite a torrent of discovery, practical and accurate diagnostic markers have remained elusive. An array of techniques have been tested and most, if not all, have ultimately been deemed to be unsuitable owing either to their impracticality or lack of specificity. Excitement is now mounting that the “holy grail” of Alzheimer’s disease diagnosis will be found by quantifying one or more of the metabolic exhaust products associated with the pathophysiological mechanisms which cause Alzheimer’s disease. An extensive literature has started to emerge and some have …