NEOPTERIN - ITS CLINICAL USE IN URINALYSIS

Increased amounts of neopterin are released during cellular immune res ponse. Neopterin concentrations can be monitored in serum and urine of patients since neopterin is removed from the circulation by renal exc retion. In allograft recipients, rising neopterin concentrations indic ate rejection episodes early. Neopterin concentrations correlate with the extent and activity of viral infections, malignancies, and autoimm une diseases. We investigated excretion kinetics of neopterin in a rhe sus monkey which received a high dose of neopterin intravenously. A sh arp increase of urinary neopterin concentrations was observed, and fro m the data the half-life of neopterin in the circulation was estimated to be 90 minutes. By comparing urine and serum neopterin concentratio ns in HIV seropositive and seronegative human individuals, a strong co rrelation and similar diagnostic sensitivity between urine and serum v alues was observed. Thus, neopterin concentrations in serum or urine s eem of equal value for diagnostic application as long as renal functio n is normal.