The impact of intercurrent EBV infection on ATP levels in CD4+ T cells of pediatric kidney transplant recipients

ImmuKnow^® measures ATP (ng/mL) in PHA-activated CD4+ T cells from patient's whole blood. According to published reports, median ImmuKnow^® is 258 ng/mL in stable pediatric kidney transplant (PKT) recipients ≥12 yr, and 165 ng/mL in those <12 yr. However, data on the effect of infection or AR on ImmuKnow^® are scarce. We studied the effect of Epstein-Barr virus (EBV) viremia on ImmuKnow^® in PKT with GD. Twenty-eight PKT with GD were reviewed. Group 1 has 19 PKT ≥12 yr, and group 2 has nine PKT <12 yr. Mean follow-up was 19.4 ± 12 months. All ImmuKnow^® values discussed in this study were measured during GD ± fever. None had ImmuKnow^® pretransplant. EBV DNA was isolated from patient blood by real-time PCR. Group 1 has eight boys and 11 girls (mean age = 16.6 ± 2.4 yr). Group 2 has two boys and seven girls (mean age = 6 ± 3.1 yr). Median ImmuKnow ^® was 292 ng/mL in group 1, and 370 ng/mL in group 2. Nine children developed EBV viremia: two in group1 (median ImmuKnow^® = 273 ng/mL), and seven in group 2 (median ImmuKnow^® = 475 ng/mL). Overall mean ImmuKnow^® in the nine EBV viremic patients was higher than that in the 19 non-viremic ones (422 ± 176 ng/mL, and 302 ± 113 ng/mL, respectively, unequal variance t-test, p = 0.08). Eight children developed AR (all in G1, median ImmuKnow^® = 272 ng/mL). In group 1, one patient developed concurrent EBV viremia and rejection, while another patient developed EBV viremia six months following a rejection episode. In group 2, none developed simultaneous AR, CMV, or BK virus infection with EBV viremia. None developed post-transplant lymphoproliferative disease. In summary, EBV viremia was paradoxically associated with high ImmuKnow^® in PKT <12 yr. This suggests strong co-stimulation of PHA-activated CD4+ T cells by EBV-transformed B cells.