Impact of anti-HLA antibodies screening techniques on waiting time on the waiting list and kidney transplant outcomes

Abstract

Background

Differences in sensitivity and specificity between the techniques used for the detection of anti-HLA antibodies before kidney transplantation (KT) can lead to contradictory results that influence patients' management. Our aim is to analyse whether the technique used, based on complement-mediated-cytotoxicity (CDC) or on microsphere fluorimetry (xMAP), conditions the waiting time until transplantation and its results.

Methods

We performed a retrospective cohort study of the KT performed in our centre from 2006 to 2018 whose pre-transplant anti-HLA specificity determination and definition of prohibited antigens was performed by CDC (2006–2011) or by xMAP (2012–2018). Living donor KT recipients were excluded. The influence of each technique on the time on the waiting list and on the outcome of kidney transplantation was analysed, using as indicators the initial function of the graft, the rate of humoral rejection and graft survival.

Results

During the period of the study, 622 patients were included (264 were studied by CDC and 358 by xMAP). Recipient and donor age was higher in the xMAP group (p < 0.001). Additionally, most sensitised patients were in the xMAP group (p < 0.001). However, they received a KT earlier. There were no differences in the rate of acute humoral rejection between groups. Nevertheless, graft survival was better in the xMAP group.

Conclusions

The introduction of the xMAP technique in our centre has meant an improvement in terms of accessibility to transplantation and the initial management of the patient. However, it does not ameliorate the indicators of graft rejection.