Clinical relevance of a CD4(+) T cell immune function assay in the diagnosis of infection in pediatric living-donor liver transplantation

The aim of the present study was to investigate the potential of the Immuknow immune cell function assay for the diagnosis of infection after pediatric living-donor liver transplantation (LDLT). Based on clinical data obtained following liver transplantation, 66 patients were divided into infection (n=28) and non-infection (n=38) groups. The following factors were considered in the present analysis: Primary disease, lymphocyte count, tacrolimus plasma concentration/dose (C(0)/D) ratio, CD4(+) T lymphocyte ATP levels, at pre-transplant stage and at weeks 1–4, and 2 and 3 months post-transplant. The CD4(+) T lymphocyte ATP values were plotted in a receiver operating characteristic (ROC) curve. The CD4(+) T lymphocyte ATP value of the infection group was significantly lower compared with that of the non-infection group (188.6±93.5 vs. 424.4±198.1 ng/ml, respectively; P<0.05). No correlation was observed between the ATP value and tacrolimus plasma C(0)/D ratio (R(2)=0.0001484); however, a correlation was reported between the ATP value and lymphocyte count (R(2)=0.2149). Analysis of the ROC curve indicated that the ATP levels of CD4(+) T cells were significantly associated with the diagnostic value of infection (area under the curve=0.866). These findings suggest that low CD4(+) T lymphocyte ATP levels may be an independent risk factor for infection following pediatric LDLT, and that the Immuknow assay may be used as a tool to evaluate T lymphocyte function in such patients to predict the risk of infection.