Plasma glutathione peroxidase activity in kidney recipients with and without adverse outcome

Kidney function is routinely monitored utilizing classic biochemical parameters including serum or plasma creatinine (Cr),
and blood urea nitrogen (BUN) concentrations. This study demonstrates that the simultaneous assessment of plasma
glutathione peroxidase (pGPx) and Cr levels provides a better strategy for the immediate follow-up of kidney function in
organ recipients. Kidney recipients (Krs; n ¼ 22) were recruited. Blood sampling schedule commenced at day 1 (pretransplantation)
and post-transplantation days (i.e., everyday from 1 until day 14, and thereafter on days 21, 28, 35, 42, 49,
and 56). pGPx was measured spectrophotometrically. Candidates for transplantation exhibited lower pGPx than control
subjects (42 � 24 vs. 143 � 31 U/L; p < 0.005). In Krs with a stable post-transplant outcome, pGPx increased to a
maximum at day 28 (214 � 61 U/L). In a Kr diagnosed with acute tubulonecrosis, pGPx provided a better predictive value
(threefold increase) than Cr. In a Kr diagnosed with acute rejection, the increment in Cr values was found to be more
pronounced than in pGPx values. The pGPx test is simple, inexpensive and automatable, and should be a valuable
diagnostic tool of kidney function in organ recipients with and without troublesome outcome for the follow-up during
hospitalization period.