Immune activation and enhanced urinary zinc concentrations in allograft recipients.

OBJECTIVES

Zinc metabolism is frequently abnormal in renal allograft recipients. These abnormalities may be immune mediated because zinc metabolism is affected by inflammation.

METHODS

We determined urinary zinc and neopterin concentrations in 24 allograft recipients (18 kidney, 3 combined kidney-pancreas and 3 liver allografts) daily for 1-41 days. In addition, serum zinc concentrations were measured in 11 patients.

RESULTS

Serum zinc was decreased and urinary zinc concentrations were increased in kidney as well as liver transplant recipients when compared with healthy controls. Urinary zinc concentrations were only slightly elevated in patients with uncomplicated post-transplant course, but the increase was more pronounced in renal allograft recipients with acute tubular necrosis. Urinary zinc concentrations were drastically increased during rejection of various organs. In addition, significant associations between urinary zinc and neopterin concentrations were observed.

CONCLUSION

Our results suggest that enhanced urinary zinc excretion in allograft recipients is due to immune activation. The data indicate that cytokines play a role in zinc metabolism.