ABSTRACT
Objective:To explore the critical value of different blood group antibody titration in ABO blood group incompatible kidney transplant(ABOi-KT)recipients by tube and gel methods to provide rationales for selecting the threshold value of antibody titration before ABOi-KT.Methods:From January 2019 to April 2021, 681 blood group antibody titrations were performed for 214 ABOi-KT recipients.There were type A( n=135), type B( n=168)and type O( n=378). The difference, correlation and consistency of two methods were statistically analyzed. Results:Tube method was 2 gradients lower than gel method(4-fold dilution)and the results were significantly different( P<0.000 1). Spearman's test indicated that the results of two methods were significantly correlated( P<0.000 1). The results of intraclass correlation coefficient showed that the consistency of two methods was general for type A recipients(ICC=0.640), decent for type B recipients(ICC=0.751)and poor for type O recipients(ICC<0.4). When the critical value of tube method was set, titration of type A anti-B was 16, titration of type B anti-A 8 and titration of type O anti-A/B 8.And the corresponding critical values of gel was type A anti-B 32, type B anti-A 16 and type O anti-A/B 16. Conclusions:The results of ABO blood group IgM antibody titration by gel and tube methods are correlative.And gel method is recommended for more stable and reproducible results.
ABSTRACT
Objective:To explore the feasibility of applying plasma with same blood group as kidney donor to ABO incompatible kidney transplantation(ABOi-KT)preconditioning of blood group O recipients with high-titer anti-A/B preformed antibody(IgM/IgG titer ≥1∶256).Methods:A total of 15 cases of blood group O ABOi-KT recipients with high-titer anti-A/B were recruited and divided into two groups of AB( n=8)and kidney donor's blood(KD, n=7)according to plasma type for plasma exchange during preconditioning phase. Clinical data of preconditioning and post-KT were recorded. Results:They received plasmapheresis(PP)(8.1±2.5)sessions in preconditioning phase, including double plasma filtration(DFPP)(4.0±1.4)sessions and plasma exchange(PE)(4.1±2.0)sessions, PP frequency was(0.8±0.1)sessions per day. No hemolysis reaction occurred during preconditioning phase. Anti-A/B titers declined as expected and fulfilled the ABOi-KT criteria(IgM/IgG titers ≤1∶8). KT was performed successfully without antibody-mediated rejection. All of them survived with normal renal function within 90 days post-KT. Levels of serum creatinine at Day 7/30/90 post-KT were(92.9±30.4), (96.2±25.9)and(103.1±28.4)μmol/L; anti-A/B IgM titers at Day 7/30/90 post-KT 1∶1-1∶32, 1∶1-1∶64 and 1∶1-1∶32; anti-A/B IgG titers at Day 7/30/90 post-KT 1∶1-1∶64, 1∶1-1∶64 and 1∶1-1∶32 respectively. No significant differences existed in count/frequency of PP sessions, levels of serum creatinine or anti-A/B titers at each observation point between AB and KD groups( P>0.05). Conclusions:Plasma with the same blood group as kidney donor is feasible for maximizing the intensity of ABOi-KT preconditioning. Favorable outcomes may be achieved through an intensified desensitization strategy on blood group O recipients with high-titer anti-A/B preformed antibody. The potential risks and long-term outcomes should be further explored.