Randomized trial of blood eosinophil count monitoring as a guide to corticosteroid dosage adjustment after heart transplantation

Background. Increases in blood eosinophil counts (EOS) beyond 0.06x10(9)/li ter precede treated heart allograft rejection. An oral prednisolone dose of 0.35 mg/kg/day usually suppresses EOS below this threshold, Methods. We designed a randomized trial to compare our empirical protocol f or steroid dose adjustment with a novel protocol guided by EOS monitoring d uring the first 3 months after heart transplantation. Eighty patients were randomized to either have their EOS reported and used for steroid dose adju stment (RG; n=40), or not reported (NG; n=40). RG; patients had their stero id dosage increased if EOS exceeded 0.06x10(9)/liter. Results. RG; patients had an 83% lower risk of treated rejection (P=0.035) and lower median intravenous dose of methyl-prednisolone (P=0.017) than NG during the first 6 postoperative weeks. The proportion of diagnostic increa ses in EOS that were followed within 2 weeks by treated rejection was 42% g reater in NG than RG; (P=0.0001), compatible with a direct impact of EOS-gu ided prednisolone dose adjustment on the risk of subsequent rejection. Over all, RG had less than half the risk of rejection of any grade (P<0.001) and significantly more rejection-free biopsies than NG (P=0.001). The mean ora l prednisolone dosage was significantly greater in RG; than NG during the f irst (P=0.014) and second (P=0.001) 6 weeks of follow-up. This did not incr ease the incidence of serious steroid-related side effects. Conclusions. EOS monitoring is a simple, cheap, and effective means of opti mizing steroid immunosuppression, Restriction of the EOS-guided steroid dos ing protocol to periods of prolonged hospitalisation during the first 3 pos toperative months should limit the requirement for higher prednisolone dosa ge without affecting immunosuppressive efficacy.