Method for Diagnosing a Person Having Sjogren's Syndrome

Method for differentiating a person having Sjögren's Syndrome or being suspected as having Sjögren's Syndrome or at risk of developing Sjögren's Syndrome, from a person with similar symptoms to those commonly observed for Sjögren's Syndrome but due to unrelated etiology, comprising the following steps:

• a) providing a sample of a body fluid or a tissue from said person, said sample containing a mixture of uncharacterized proteins, peptides or protein fragments naturally occurring in the sample;
• b) pre-processing the patient sample as necessary to make it amenable to analysis by mass spectrometry;
• c) generating a mass spectrum of the protein-, protein fragment- and peptide-containing patient sample;
• d) applying mathematical algorithm(s) to differentiate whether the mass spectrum of the sample has features, biomarkers, or patterns of biomarkers that are characteristic of, or in common with, other samples, similarly processed and analyzed, and derived from persons known to have Sjögren's Syndrome (Sjögren's Syndrome “fingerprint” or reference database), or analyzing the patient sample to determine the presence or level of a protein, protein fragment or peptide corresponding to the biomarkers identified through mass spectrometry and classified as belonging to the Sjögren's Syndrome fingerprint group or reference database;
• and
• e) diagnosing Sjögren's Syndrome in the person or excluding the person as having Sjögren's Syndrome, depending on whether the person's sample is classified by the algorithm(s) into the Sjögren's Syndrome fingerprint or reference database relative to non-Sjögren's Syndrome-derived samples, or from the presence or level of a protein, protein fragment or peptide associated with the biomarkers identified by mass spectrometry.