RENAL GRAFT-REJECTION OR URINARY-TRACT INFECTION - THE VALUE OF MYELOPEROXIDASE, C-REACTIVE PROTEIN, AND ALPHA-2-MACROGLOBULIN IN THE URINE

Previous investigations have shown that the determination of two acute -phase proteins in the urine, C-reactive protein (CRPu) and alpha 2-ma croglobulin (alpha 2-MGu), allows a noninvasive diagnosis of acute ren al graft dysfunction. A reliable differentiation between rejection and urinary tract infection can be made only when considering the C-react ive protein in serum and urine at the same time (CRPs:CRPu ratio). The refore, a diagnostic procedure independent of parameters other than ur inary proteins is needed, As granulocytes play only a minor role in gr aft rejection but are a common feature in urinary tract infection, we determined a marker of granulocytes (myeloperoxidase) in urine (MPOu). Eighty-nine renal transplant recipients were included in the study. I n normal courses, CRPu, alpha u2-RMGu, and MPOu were within the normal range. In 15 cases of acute interstitial rejection, an increased excr etion of CRPu and alpha 2-MGu could be confirmed, but MPO could not be detected. On the occasion of acute vascular rejection (n=6), with the exception of one case, MPOu could not be observed, The pattern of the three urinary proteins differed in urinary tract infections (n=40): M POu could be detected in all cases, CRPu in 50% of cases, and alpha 2- MGu in 73% of cases. In patients with cytomegalovirus infection (n=7), no MPOu, CRPu, or alpha 2-MGu was found, In conclusion, the simultane ous measurement of the three proteins allows a complete, noninvasive, differential diagnostic procedure of renal graft dysfunction.