Pathophysiological changes in patients during hemodialysis and blood reinfusion predict potential development of hemodialysis reactions.

Hemodialysis reactions (HDRs) are a type of hypersensitivity reactions (HSRs), such as complement activation-related pseudoallergy (CARPA) observed during nanoparticle infusions. Our study aimed to elucidate the mechanisms of human HDRs by focusing on hemodynamic and clinical chemistry changes of HSR-related or biocompatibility issues during human hemodialysis (HD) and the reinfusion of blood. Based on our recent animal experiments, we hypothesize that increased pulmonary arterial pressure (PAP), and increases in thromboxane B2 (TXB2) and complement 3a (C3a) plasma concentrations will likely manifest in, or at least predict, human HDRs during HD and blood reinfusion. To verify our hypothesis, we measured these parameters during high-flux HD in patients. Since direct PAP measurement was not possible, the plasma concentration of the N-terminal fragment of the brain natriuretic peptide (NT-proBNP) was determined for the noninvasive estimation of PAP. Our results show an increase in NT-proBNP and TXB2 during the reinfusion of extracorporeal blood. The plasma concentration of C3a increased in early HD already and remained elevated up to blood reinfusion. In conclusion, the observed changes in HSR-related parameters or biocompatibility issues in otherwise asymptomatic patients may suggest that a greater activation of these mechanisms could explain the development of human hemodialysis reactions.