Patent ID: 9606113
Date: 2017-03-28
CPC Classifications: G01N

Claim:
1. An in vitro method for diagnosing subjects with Alzheimer's disease or Parkinson disease with dementia among subjects suffering from dementia selected from the group consisting of Alzheimer's disease, Parkinson disease, Parkinson disease with dementia, amyotrophic lateral sclerosis, and Creutzfeldt-Jacob's disease, said method comprising the steps of selecting exclusively dopamine, adrenaline and noradrenaline in a sample of biological fluid from said subject and of a1) incubating said dopamine, adrenaline and noradrenaline in said sample with 3,6-diamino-9-[2,4(or 2,5)-dicarboxyphenyl]-4,5-disulfoxanthylium inner salt lithium salt (1:3); a2) measuring separately the molar concentration of each of said dopamine, adrenaline and noradrenaline derivatized with 3,6-diamino-9-[2,4(or 2,5)-dicarboxyphenyl]-4,5-disulfoxanthylium inner salt lithium salt (1:3); a3) determining a virtual value by combining the levels measured in step a2) applying one of the following algorithms: wherein V is the virtual value to be determined and [i] is the level of said dopamine, [ii] is the level of said adrenaline and [iii] is the level of said noradrenaline; and a4) comparing the virtual value determined in step a3) with a threshold value based on a number of healthy patients, a number of patients suffering from Alzheimer's disease and a number of patients suffering from Parkinson disease with dementia, using the same algorithm as used for determining the virtual value in step a3); and b) determining whether said subject suffers from Alzheimer's disease or Parkinson disease with dementia when the virtual value determined in step a3) is lower than said threshold value.