Use of precursors of tachykinins and/or their fragments in medical diagnostic

An in vitro method for measuring a concentration of protachykinin, protachykinin slice variants and fragments thereof comprising at least amino acids 1-37 of protachykinin in a sample from the circulation of a patient, said method comprising:

• reacting said sample with a first antibody that specific binds to an epitope within amino acids 3-21 of SEQ ID NO:
• 10, and a second antibody, wherein the second antibody specifically binds to a peptide consisting of the amino acid sequence DADSSIEKQVALLK (SEQ ID NO:13), wherein one of said first and second antibodies comprises a detectable label, for a time sufficient for said first and second antibodies to become bound to protachykinin, a protachykinin splice variant and/or fragments thereof comprising at least amino acids 1-37 of protachykinin in the sample, removing unbound label;
• measuring bound detectable label to determine a concentration of bound detectable label, wherein the concentration of bound detectable label correlates to the concentration of protachykinin, protachykinin splice variants and fragments thereof comprising amino acids 1-37 in said sample;
• and comparing said concentration of protachykinin, protachykinin splice variants and/or fragments thereof comprising at least amino acids 1-37 of protachykinin to a concentration in the normal range for healthy individuals, wherein an increased concentration of said protachykinin, protachykinin splice variants and/or fragments thereof comprising amino acids 1 to 37 in said sample indicates the presence of sepsis, tumor, cancer, Alzheimer's disease or stroke.