Impaired oxidative metabolism by leukocytes from renal transplant recipients: a potential mechanism for the increased susceptibility to infection.

Stimulated neutrophils exhibit a burst of oxidative metabolism which results in the formation of superoxide anion and other oxygen species that participate in bacterial killing. Chemiluminescence which is also produced is a sensitive measure of oxidative metabolism and correlates well with antimicrobial activity. Because infection is an important cause of morbidity and mortality in renal transplant recipients we examined chemiluminescence and superoxide production by leukocytes from transplant patients in response to a soluble (phorbol myristate acetate) and to a particulate stimulus (opsonized zymosan). Using phorbol myristate acetate as a stimulus, leukocytes from patients had a reduced chemiluminescence response [controls 515 +/- 105, n = 18; patients 225 +/- 40, peak cpm X 10(3)/10(6) PMN, n = 13, (P less than 0.05)] and reduced superoxide anion production [controls 43.3 +/- 3.4, n = 18, patients 29.3 +/- 3.9 nmoles/15 min/10(6) PMN, n = 13 (P less than 0.025)]. Significantly reduced chemiluminescence response (P less than 0.025) and superoxide production (P less than 0.05) were also observed using opsonized zymosan as a stimulus. The impaired oxidative burst by leukocytes may contribute to impaired microbial killing and may explain the increased morbidity and mortality from infection in renal transplant patients.