Methods and compositions for diagnosis and prognosis of renal injury and renal failure

Abstract

The present invention relates to methods and compositions for monitoring, diagnosis, prognosis, and determination of treatment regimens in subjects suffering from or suspected of having a renal injury. In particular, the invention relates to using a plurality of assays configured to detect a kidney injury marker as diagnostic and prognostic biomarkers in renal injuries.

We claim: 
     
         1 . A method for evaluating biomarker levels in a plasma or urine sample from a subject, comprising:
 obtaining a plasma or urine sample from a subject that suffers from current acute renal injury;   performing a plurality of assays comprising a first assay configured to detect Beta-2-microglobulin and a second assay configured to detect WAP four-disulfide core domain protein 2 by introducing the plasma or urine sample obtained from the subject into an assay instrument which (i) for each analyte binding assay performed, contacts all or a portion of the plasma or urine sample with a binding reagent which specifically binds for detection the kidney injury marker which is assayed, and (ii) generates a first assay result indicative of binding of Beta-2-microglobulin to its respective binding reagent and a second assay result indicative of binding of WAP four-disulfide core domain protein 2 to its respective binding reagent;   combining the first and second assay results using a function that converts the first and second assay results into a single composite result; and   correlating the single composite result to a likelihood that the renal function of the subject will improve within 72 hours of the time at which the plasma or urine sample is obtained from the subject by using the single composite result to assign the subject to a predetermined subpopulation of individuals having a current acute renal injury and that have a known predisposition to the nonoccurrence of acute renal failure within 72 hours.   
     
     
         2 . A method according to  claim 1 , wherein said correlating step comprises correlating the single composite result to a likelihood that the renal function of the subject will improve within 48 hours of the time at which the plasma or urine sample is obtained. 
     
     
         3 . A method according to  claim 1 , wherein said correlating step comprises correlating the single composite result to a likelihood that the renal function of the subject will improve within 24 hours of the time at which the plasma or urine sample is obtained. 
     
     
         4 . A method according to  claim 1 , wherein the subject is in RIFLE stage I or F. 
     
     
         5 . A method according to  claim 2 , wherein the subject is in RIFLE stage I or F. 
     
     
         6 . A method according to  claim 3 , wherein the subject is in RIFLE stage I or F.