ABO-incompatible kidney transplantation in elderly patients over 60?years of age

Introduction

Patients aged 60?years and older represent the fastest-growing population with end-stage renal disease worldwide, and the need for a kidney transplant among this population is increasing. Due to the severe shortage of deceased donors in Japan, ABO-incompatible living donor kidney transplantation has been performed since the late 1980s. Excellent long-term outcomes have been achieved, and the rates of graft survival in these patients are currently similar to those in recipients of ABO-compatible grafts. However, the outcomes of ABO-incompatible kidney transplantation in elderly patients over 60?years of age have not been well studied yet.

Patients and methods

We studied 4 elderly kidney transplant patients who received their grafts from ABO-incompatible living donors at our institution between December 2006 and December 2011, focusing on the immunosuppressive protocols, complications and graft survivals. The mean observation period was 21.5?months (range, 8?months to 62?months). Our immunosuppressive protocols were as follows: to remove the anti-A/B antibodies, the patients underwent 4?C8 sessions of double-filtration plasmapheresis and/or plasma exchange prior to kidney transplantation until the anti-A/B titers were less than 1:16. For the patients with low anti-A/B titers (<1:512), the immunosuppressive protocol consisted of a single dose of rituximab (150?mg/m²). The patients with high anti-A/B antibody titers (??1:512) underwent splenectomy and received 2 doses of rituximab. The pretransplant immunosuppressive protocol included B-lymphocyte suppression with 4?weeks of mycophenolate mofetil (0.5?g/day for low-titer protocol and 1?g/day for high-titer protocol).

Results

All 4 patients underwent successful transplantation. At the end of follow-up, their mean serum creatinine was 1.18?mg/dl. No patient experienced antibody-mediated rejection or acute cellular rejection. Late-onset neutropenia occurred in two cases. Two cases experienced cytomegalovirus reactivation by cytomegalovirus antigenemia. In one patient, diffuse hemorrhage required surgical intervention. However, there were no severe complications.

Conclusions

Although a careful evaluation of patients is needed, ABO-incompatible kidney transplantation may become a viable treatment option for elderly patients with end-stage renal disease.     

Desensitization protocol in highly HLA-sensitized and ABO-incompatible high titer kidney transplantation

Background

A positive crossmatch indicates the presence of donor-specific alloantibodies and is associated with a graft loss rate of >80%; anti-ABO blood group antibodies develop in response to exposure to foreign blood groups, resulting in immediate graft loss. However, a desensitization protocol for highly HLA-sensitized and ABO-incompatible high-titer kidney transplantation has not yet been established.

Methods

We treated 6 patients with high (≥1:512) anti-A/B antibody titers and 2 highly HLA-sensitized patients. Our immunosuppression protocol was initiated 1 month before surgery and included mycophenolate mofetil (1 g/d) and/or low-dose steroid (methylprednisolone 8 mg/d). Two doses of the anti-CD20 antibody rituximab (150 mg/m²) were administered 2 weeks before and on the day of transplantation. We performed antibody removal with 6–12 sessions of plasmapheresis (plasma exchange or double-filtration plasmapheresis) before transplantation. Splenectomy was also performed on the day of transplantation. Postoperative immunosuppression followed the same regimen as ABO-compatible cases, in which calcineurin inhibitors were initiated 3 days before transplantation, combined with 2 doses of basiliximab.

Results

Of the 8 patients, 7 subsequently underwent successful living-donor kidney transplantation. Follow-up of our recipients showed that the patient and graft survival rates were 100%. Acute cellular rejection and antibody-mediated rejection episodes occurred in 1 of the 7 recipients.

Conclusions

These findings suggest that our immunosuppression regimen consisting of rituximab infusions, splenectomy, plasmapheresis, and pharmacologic immunosuppression may prove to be effective as a desensitization protocol for highly HLA-sensitized and ABO-incompatible high-titer kidney transplantation.     

Role of anti-A/B antibody titers in results of ABO-incompatible kidney transplantation

BACKGROUND: Our previous studies showed that the incidence of humoral rejection was extremely high in ABO-incompatible living kidney transplantation. This result suggests that anti-A/B antibody titers directly influence the graft survival of ABO-incompatible kidney transplantation. In this study, we examined the impact of preoperative anti-A/B antibody titers on the results of ABO-incompatible living kidney transplantation. METHODS: Sixty-seven patients underwent ABO-incompatible living kidney transplantation at our institution between January 1989 and December 1995. The mean age was 34.9 years with 38 males and 29 females. Sixty-one of the 67 recipients were included in an analysis of the impact of anti-A/B antibody titer in long-term graft survival. The remaining six patients were excluded because of death with a functioning graft (three patients) and withdrawal of immunosuppression due to nonimmunological reasons (three patients) within 1 year after renal transplantation. RESULTS: The graft survival rate for the level of less than 1:16 in maximum IgG antibody before transplantation (n=21) at 1, 5, and 8 years was 81.0, 66.8, and 66.8%, respectively. The corresponding values for the level of 1:32-1:64 (n=33) and higher than 1:128 (n=7) were 93.9, 90.5, and 79.7%, and 42.9, 28.6, and 28.6%, respectively (log-rank test, P=0.0007). There was no significant association between maximum anti-A/B IgM titers, minimum anti-A/B IgM titers, minimum anti-A/B IgG titers, and graft survival. CONCLUSIONS: Preoperative maximum anti-A/B IgG titers correlated with the long-term graft survival in ABO-incompatible living kidney transplantation. Thus, preoperative maximum levels of anti-A/B IgG titers are one of the good predictors of the results of ABO-incompatible living kidney transplantation.     

Acute Anti-A/B Antibody-Mediated Rejection After ABO-Incompatible Kidney Transplantation Treated With Bortezomib and Plasmapheresis: A Case Report

BackgroundABO-incompatible kidney transplantation (KTP) is effective for avoiding transplantation-related issues. It is a viable alternative to ABO-compatible KTP, as both techniques have similar patient and graft survival rates. However, anti-A/B antibody-mediated rejection (AMR) can occur, resulting in poor long-term graft survival.CaseA 45-year-old man with end-stage renal disease presented with a serum creatinine level of 10.2 mg/dL. We decided to perform KTP with spousal donation. He had panel-reactive antibody class I and II and cross matching test negativity, a 3/6 mismatch on human leukocyte antigen typing, an ABO antibody titer of 1:256, and no donor-specific antibodies. The patient and donor blood types were O+ and A+, respectively. The anti-A/B antibody titer was reduced preoperatively with rituximab (200 mg/body), plasmapheresis, and intravenous immunoglobulin (0.2 mg/kg). Basiliximab and methylprednisolone were used for induction immunosuppression, and tacrolimus, mycophenolate mofetil, and prednisolone were used for maintenance immunosuppression. KTP was successful, and graft function was initially normal. On postoperative day (POD) 5, the serum creatinine level and anti-A/B antibody titer increased from 0.9 mg/dL to 1.9 mg/dL and 1:16 to 1:64, respectively. Graft biopsy revealed acute AMR and tubular injury. We started steroid pulse therapy, plasmapheresis, and subcutaneous bortezomib (2.6 mg, twice a day, every 3 days) with no side effects. The serum creatinine level decreased from 5.7 mg/dL to 1.5 mg/dL on POD 28. Graft biopsy showed no rejection, and normal function was maintained for 40 months.ConclusionsAcute, early anti-A/B AMR was successfully treated with plasmapheresis and bortezomib.     

ABO-incompatible kidney transplantation using antigen-specific immunoadsorption and rituximab: a single center experience

BACKGROUND: For years ABO-incompatible kidney transplantations were preferentially performed in Japanese centers. In order to overcome the increased risk of humoral rejections, patients were treated with multiple sessions of plasmapheresis, intensified immunosuppressive therapy and splenectomy before transplantation. Despite good long-term results regarding patient and organ survival rates, increased morbidity during the early post-transplant period prevented a broad application of this method. Recently, a new protocol including the anti-CD20-antibody (Ab) rituximab and blood group-specific immunoadsorption instead of splenectomy and plasmapheresis was published with excellent short-term results. METHODS: From April 2004 to September 2005, 11 patients were prepared for ABO-incompatible transplantation. All patients received 375 mg/m2 rituximab intravenous 3 to 4 weeks before transplantation. Immunosuppressive therapy consisted of tacrolimus, mycophenolate mofetil and prednisone and was started at least 7 days before transplantation. Intravenous immunoglobulins (0.5 g/kg) were administered the day before transplantation. Immunoglobulin G (IgG)-anti-A or -B Ab titers before starting immunoadsorption treatment ranged between 1 : 4 and 1 : 1024. Immunoadsorption treatment was started in parallel with immunosuppressive medication and was continued until the anti-A or anti -B Ab titers (IgG and IgM) were lowered to the aimed pre-transplant threshold of <1 : 8. During the early postoperative period, additional immunoadsorption treatments were performed, if the titers increased again above 1 : 8 (days 0 to 7) or 1 : 16 (days 8 to 14), respectively. RESULTS: Transplantation could be conducted in eight of 11 patients (two females, six males, mean recipient age 52+/-11 yr). The mean follow-up was 7.0 months (range 4 to 17). The blood group constellation was A1 to 0 in four cases, A2 to 0 in two cases, B to A in one case, and A1 to B in another case, respectively. On average, each patient received seven immunoadsorption treatments. All transplants showed primary function and no humoral rejections occurred. Three of our 11 patients showed rapid increases of isoagglutinin titers after each immunoadsorption treatment and thus could not be transplanted. One patient died 4 months after transplantation with a functioning graft due to sepsis secondary to pseudomembranous enterocolitis. The mean creatinine value of the remaining seven patients now is 1.6 mg/dl. SUMMARY: The use of antigen-specific immunoadsorption and an immunosuppressive regimen consisting of a conventional triple immunosuppressive therapy has shown excellent short-term results. The immunoadsorption treatment using antigen-specific columns is highly effective and even patients with high isoagglutinin titers can be transplanted. This protocol is an option for end-stage renal disease patients who have no blood group-compatible donor.     

Successful ABO-incompatible kidney transplantations without splenectomy using antigen-specific immunoadsorption and rituximab

BACKGROUND: Historically, ABO-incompatible kidney transplantations have only been undertaken after splenectomy and unspecific plasmapheresis and with quadruple drug immunosuppression plus B-cell specific drugs. We have evaluated a protocol for ABO-incompatible kidney transplantation without splenectomy using antigen-specific immunoadsorption, rituximab, and a conventional triple-drug immunosuppressive regimen. METHODS: The protocol called for a 10-day pretransplant conditioning period starting with one dosage of rituximab and followed by full dose tacrolimus, mycophenolate mofetil, and prednisolone. Antigen-specific immunoadsorption was performed on pretransplant days -6, -5, -4, and -1. After the last session, 0.5 g/kg of intravenous immunoglobulin was administered. Postoperatively, three more apheresis sessions were given every third day. Furthermore, if there was a significant increase in the antibody titers, extra sessions were considered. RESULTS: Four patients have received transplants with this protocol. The donor-recipient blood groups were A2/O, B/O, B/A, and A1/O. The ABO-antibodies were readily removed by the antigen-specific immunoadsorption and were kept at a low level posttransplantation by further adsorptions. There were no side effects, and all patients have normal renal-transplant function. CONCLUSIONS: We conclude that after one infusion each of rituximab and intravenous immunoglobulin and antigen-specific immunoadsorption, blood-group-incompatible renal transplantations can be performed with standard immunosuppression and without splenectomy.     

Plasmapheresis, CMV Hyperimmune Globulin, and Anti-CD20 Allow ABO-Incompatible Renal Transplantation Without Splenectomy

The majority of preconditioning protocols developed to allow ABO-incompatible (ABOi) renal transplantation include concurrent splenectomy as a prerequisite to successful engraftment. Our center has developed a preconditioning protocol that includes plasmapheresis (PP), low-dose CMV hyperimmune globulin (CMVIg), and anti-CD20 monoclonal antibody (rituximab) to allow ABOi renal transplantation without splenectomy. Our initial experience has included treatment of six recipients and successful transplantation from blood group A(1), A(2), and group B living donors. Mean (+/- SD) serum creatinine was 1.3 +/- 0.1 mg/dL among the six recipients and no episodes of antibody-mediated rejection (AMR) occurred at a median follow-up of 12 months. ABO antibody titers have remained below pretreatment levels. The absence of AMR and stable allograft function in this series show the potential of this preconditioning protocol to increase ABOi renal transplantation. The use of rituximab, allowing avoidance of splenectomy, may further remove one of the significant disincentives to ABOi transplantation, and eliminate the risk of post-splenectomy infections.     

Successful A1-to-O ABO-incompatible kidney transplantation after a preconditioning regimen consisting of anti-CD20 monoclonal antibody infusions,splenectomy, and double-filtration plasmapheresis

BACKGROUND: ABO-incompatible kidney transplantations require the anti-ABO antibody titer to be reduced to below 1:16 before transplantation. To achieve this, preoperative plasma exchange or double-filtration plasmapheresis (DFPP) is usually performed. We report a case of an ABO-incompatible kidney transplantation in which preoperative DFPP failed to reduce the anti-ABO antibody titer to below 1:16. In this case, the kidney transplantation was performed after the completion of a preconditioning regimen consisting of infusions of an anti-CD20 monoclonal antibody (rituximab), DFPP, and a splenectomy. METHODS AND RESULTS: The patient was a 22-year-old man with Alport syndrome, who had been receiving dialysis treatment for 17 months. Because the patient's blood type was O, and the donor's was A (A1), three sessions of DFPP were performed 2 months before the kidney transplantation. However, the patient's anti-A antibody titer did not drop to below 1:16, so the kidney transplantation was postponed. To enable the ABO-incompatible kidney transplantation to proceed, the following protocol was applied. Rituximab was infused weekly at a dose of 375 mg/m for 4 weeks. After the first rituximab infusion, the CD19+ B cell count rapidly decreased to below 1% in the peripheral blood. Two days after the fourth rituximab infusion, splenectomy was performed. After the splenectomy, four sessions of DFPP were performed. During the course of DFPP treatment, the anti-A antibody titer gradually decreased and was below 1:16 on the day of the transplantation. The kidney transplantation was performed by the standard method. The kidney allograft was performed immediately after the transplantation. No signs of humoral rejection were observed after revascularization. After the operation, the patient showed no signs of humoral rejection, and his serum creatinine levels were between 1.7 and 2.0 mg/dL. The anti-A antibody titer remained below 1:16 throughout the recovery period. A biopsy specimen obtained on postoperative day 12 showed no evidence of antibody-mediated rejection. After 3 months of follow-up, the kidney allograft continued to function well. CONCLUSION: A preconditioning regimen consisting of rituximab infusions and a splenectomy is a useful new strategy for performing ABO-incompatible kidney transplantations when the conventional preconditioning regimen does not work.     

ABO-incompatible live donor renal transplantation using blood group A/B carbohydrate antigen immunoadsorption and anti-CD20 antibody treatment

BACKGROUND: Blood group ABO-incompatible live donor (LD) renal transplantation may provide a significant source of organs. We report the results of our first 14 cases of ABO-incompatible LD renal transplantation using specific anti-A/B antibody (Ab) immunoadsorption (IA) and anti-CD20 monoclonal Ab (mAb) treatment. PATIENTS AND TREATMENT PROTOCOL: Recipients were blood group O (n = 12), A (n = 1) and B (n = 1). Donors were A1 (n = 2), A2 (n = 3), A2B (n = 1) and B (n = 8), and all were secretor positive. Anti-human leukocyte antigen (HLA) Ab panel reactivity was negative in all recipients except one. All recipients were pre-treated with 3 to 6 IA sessions, using A or B carbohydrate antigen columns, until their anti-A1/B RBC panel indirect antiglobulin test (IAT) titers were < or =8. CDC crossmatch was negative in all cases. Recipients received preoperative mycophenolic acid, and steroids/tacrolimus were started at transplantation. No splenectomy was performed. Eight recipients received one dose of anti-CD20 mAb (rituximab, 375 mg/m2) pre-operatively and 11 recipients had postoperative protocol IA. RESULTS: In the initial protocol, anti-CD20 mAbs were used only for recipients receiving A1 grafts. One B graft (HLA-identical donor, 84% panel reactivity) was lost in a severe anti-B Ab-mediated acute rejection. Subsequently, the protocol included anti-CD20 for recipients of both A1 and B grafts and postoperative protocol IA to all recipients. The subsequent 10 grafts had excellent function, giving a total graft survival of 13/14 (observation range 2 to 41 months). At 1 yr, mean serum creatinine was 113 micromol/l (n = 8) and mean glomerular filtration rate was 55 ml/min/1.73 m2 (range 24 to 77). In the remaining five cases, with less than 1 yr follow up, mean serum creatinine was 145 micromol/l at 2 to 9 months follow up. Pre-IA anti-A/B titers were in the range of 2 to 32 (NaCl technique) and 16 to 512 (IAT). More than 90 IA sessions were performed in 14 recipients without any significant side effects. Recipient anti-A/B titers returned after transplantation to pre-IA levels or slightly lower. Postoperative renal biopsies were performed in 10 patients. In the 13 patients with long-term function, one patient experienced cellular rejection (Banff IIB) at 3 months without anti-B titer rise. This rejection was concomitant with low tacrolimus plasma levels and was easily reversed by steroids. In 8 of 10 cases, C4d staining was positive in peritubular capillaries. CONCLUSION: Blood group ABO-incompatible LD renal transplantation using A and B carbohydrate-specific IA and anti-CD20 mAbs has excellent graft survival and function.     

Experiences and problems pre-operative anti-CD20 monoclonal antibody infusion therapy with splenectomy and plasma exchange for ABO-incompatible living-donor liver transplantation

BACKGROUND: ABO-incompatible living-donor liver transplantation (LDLT) requires a reduction of the anti-ABO antibody titer to <16 before transplantation, which is usually achieved by pre-operative plasma exchange (PE) or double-filtration plasmapheresis. ABO-incompatible transplantations have been performed after a splenectomy with heavy drug immunosupression plus B-cell-specific drugs. Here, we evaluated a pre-transplantation infusion protocol with an anti-CD20 monoclonal antibody (rituximab) for ABO-incompatible LDLT. METHODS: Between March 2002 and December 2005, 73 adult patients underwent LDLT without retransplantation in our institution. Among these cases, 57 were ABO-identical, 11 were ABO-compatible and five were ABO-incompatible. The rituximab infusion protocol consisted of a weekly infusion of rituximab (375 mg/m(2)) for three wk, which was administered to three of the five ABO-incompatible LDLT patients. All three patients underwent a pre-operative PE, as well as a splenectomy during the operation. A triple immunosuppression protocol of tacrolimus, low-dose steroids and mycophenolate mofetil (1500 mg/d) was administered post-operatively. In addition, the patients received a continuous intra-arterial infusion of prostaglandin E(1) and methylprednisolone, and a continuous intra-portal infusion of a protease inhibitor for three and two wk after transplantation, respectively. RESULTS: After the first rituximab infusion, the peripheral blood CD19(+) B cell count rapidly decreased to <1%. All three patients treated with rituximab subsequently received an ABO-incompatible LDLT, with donor/recipient blood groups of B/O, A(1)/B and A(1)/O. In two cases, the ABO-antibody level transiently increased post-operatively, then decreased and remained low. Rituximab infusion therapy did not develop any direct side effect except for mild allergic reaction to the first infusion, but post-operatively all three patients suffered a cytomegalovirus and were successfully treated with ganciclovir, and one patient had a MRSA-positive intra-abdominal abscess. Two patients are currently alive at 20 and 18 months respectively, and show normal graft-liver function. But one patient died of sepsis because of intra-abdominal abscess. CONCLUSIONS: Although the protocol of rituximab administration is a conventional and safe regimen with no major side effects, the development of a new protocol is needed for prevention of the infection with bone suppression.     

ABO Blood Type Incompatible Kidney Transplantation Without Splenectomy Prepared With Plasma Exchange and Rituximab

We have designed a protocol for ABO-incompatible kidney transplantations based on preoperative plasmapheresis with a tacrolimus/mycophenolate mofetil/methylprednisolone/basiliximab protocol using low-dose rituximab (200 mg/body) instead of splenectomy to prevent antibody-mediated acute rejection. Eight patients successfully received transplants with this protocol. The titers of anti-A and -B antibodies as well as the number of CD20⁺ cells were readily maintained at a low level posttransplantation. There were no side effects. All patients have renal transplant function with a follow-up of 1-34 months.     

Management of an ABO-Incompatible Lung Transplant

A 24-year-old woman with cystic fibrosis underwent bilateral sequential lung transplantation and unintentionally received an ABO incompatible graft (blood type A(1) graft into a type O recipient). The recipient had a high titer of IgG anti-A antibody (256 by the indirect antiglobulin test). Emergency treatment included antibody removal by plasmapheresis and additional immunosuppression with mycophenolate, rabbit antithymocyte globulin and polyspecific intravenous immunoglobulin. Subsequently, immunoadsorption and the anti-CD20 antibody rituximab were used to remove anti-A antibody and inhibit its resynthesis. Early graft function was good; one episode of rejection at Day 46 responded promptly to treatment with methylprednisolone. Subsequently, graft function continued to improve and anti-A antibody titers remained low. No infectious or other complications were encountered. The treatment regimen that we adopted may prove useful in other cases of unplanned ABO-incompatible organ transplants. The successful outcome suggests that planned ABO-incompatible lung transplants may be possible.     

Long-term follow-up ABO-incompatible adult living donor liver transplantation in cirrhotic patients

ABO-incompatible liver transplantation is usually contraindicated. The presence in the recipient of preformed anti-A/B antibodies located on endothelial cells raises the risk of antibody-mediated humoral rejection of the graft. We describe four successful cases of steroid withdrawal in adult patients who had living-donor liver transplantation from ABO-incompatible donors. Antirejection therapy included multiple perioperative plasmapheresis, splenectomy, and a triple immunosuppressive regimen with tacrolimus, methylprednisolone (MPSL), and cyclophosphamide or mycophenolate mofetil (MMF). The maintenance dose of immunosuppression did not differ from that of ABO-identical cases. After transplantation, intrahepatic arterial infusion therapy with prostaglandin E1 (PG E1) was used. As a result, all four patients were able to achieve long-term graft survival without steroid use. They all have good liver function and are leading normal lifestyles. Our experience with these four patients suggests the feasibility of controlling humoral rejection and other complications in adult ABO-incompatible living donor liver transplantations with intrahepatic arterial infusion of PGE1, splenectomy, and plasmapheresis with a regular base of immunosuppression protocol to prevent antibody-mediated humoral rejection.     

Experience with laparoscopic splenectomy for ABO-incompatible living renal transplantation without plasmapheresis

A 25-year-old male, blood type A, was admitted to our hospital for renal transplantation from his father of AB blood type. Before transplant, we performed laparoscopic splenectomy. The serum anti-B antibody titer fell from 1:8 to 1:2. Therefore, plasmapheresis was not performed. The total ischemic time was 80 minutes. Five immunosuppressive agents, including tacrolimus, mycophenolate mofetil, prednisolone, basiliximab, and deoxyspergualine, were administered in the initial period. On the 47th day, value of cytomegalovirus antibody, which was routinely measured, became positive. Hence, we administered ganciclovir, with a fall in antibody. Sixty-five days after transplant, he was discharged with a serum creatinine of 1.0 mg/dL. We concluded that it was possible to perform ABO-incompatible renal transplantation with no need for plasmapheresis or rituximab.     

ABO-incompatible living-donor kidney transplantation in children

BACKGROUND: Due to a severe shortage of suitable cadaveric allografts for children awaiting kidney transplants, we have performed a series of ABO-incompatible living kidney transplantations (LKT) at our institution. METHODS: Between July 1989 and March 2000, 16 pediatric patients (3 female, 13 male) underwent ABO-incompatible LKT. The mean age at transplantation was 10.9+/-4.3 years (range 5.1-15.0 years). The donor to recipient ABO blood antigen incompatibility was as follows: A1-->O, 5 patients; B-->O, 6 patients; A1B-->B, 2 patients; and A1B -->B, A1-->B, or B-->A1, 1 patient each. The median pretransplantation anti-A1 titers of eight A-incompatible recipients were 1:128 (IgM, range 1:16 to 1:512) and 1:32 (IgG, range 1:2 to 1:128). Median anti-B titers of seven B-incompatible recipients were 1:32 (IgM, range 1:4 to 1:128) and 1:8 (IgG, range 1:2 to 1:64). All patients received three or four sessions of plasmapheresis (PP) and/or immunoadsorption (IA) to remove the anti-A and/or anti-B antibodies before transplantation. Immunosuppression initially consisted of cyclosporine, methylprednisolone, cyclophosphamide, and antilymphocyte globulin. Splenectomy was performed on all recipients at the time of transplantation. RESULTS: The patients were followed for 6 to 122 months with a mean follow-up of 63 months. All 16 recipients who underwent ABO-incompatible LKT achieved a pretransplant isoagglutinin titer less than 1:8 with 3-4 sessions of PP/IA treatment. Of 16 patients, 10 patients had rebound increase in their IgM and/or IgG anti-A/B titers to greater than 1:64 or predepletion levels within 10 days posttransplantation. In addition, nine patients developed renal dysfunction in association with the rebound increase in their anti-A/B. One patient lost his graft because of uncontrolled delayed hyperacute rejection, whereas eight other recipients recovered completely with pulse steroids and PP/IA therapy. After the third week posttransplant, there was no correlation between the occurrence of AR and their isoagglutinin titers. Moreover, no antibody-mediated rejection was observed, even in recipients with continued high titer anti-A and/or anti-B antibodies. Patient survival is 100% to date. The actuarial 1-year and 5-year graft survival rates are 87% and 85%, respectively. No fatal infectious complications occurred despite the combination of splenectomy and immunosuppressive drugs. CONCLUSIONS: We have demonstrated that with adequate pre- and posttransplant management, successful kidney transplantation across the ABO barrier is possible in the pediatric population. "Accommodation" of the allografts occurred within 2 weeks of transplantation. Subsequently, the long-term graft outcome of ABO-incompatible LKT was comparable to that of ABO-compatible LKT.     

Desensitization with the Use of an Antibody Removal–Free Protocol in ABO-Incompatible Kidney Transplant Recipients with a Low Anti-A/B Antibody Titer

Background

Desensitization for ABO-incompatible (ABOi) kidney transplantation mainly comprises removal of antibodies with the use of apheresis and suppression of antibody (Ab) production with the use of rituximab. This study aimed to estimate the outcomes of ABOi kidney transplantation with the use of an Ab removal–free protocol to avoid complications associated with apheresis.

Immunization by blood-type antigen in human immunoglobulin products before ABO-incompatible kidney transplantation

A 29-year-old man wanted to receive an ABO-incompatible kidney transplant. His blood type was O, and the donor, his father, was A1. After endoscopic splenectomy performed before kidney transplantation, the recipient developed a high fever and leukocytosis, and he was treated with antibiotics and 5 g of human immunoglobulin products by intravenous infusion for 3 d. Soon after the infusions, his anti-blood type A antibody titer (anti-A titer) rose, and several sessions of plasma-exchange (PEX) and double-filtration plasmapheresis (DFPP) failed to lower it. Three courses of anti-CD20 monoclonal antibody were administered to suppress the antibody production more specifically, and the rituximab infusions and repeated PEX and DFPP session lowered the anti-A titer and enabled kidney transplantation. Mild humoral rejection was observed 16 d after transplantation, but the recipient's serum creatinine was 1.5 mg/dL when discharged from the hospital. The increased anti-A titer may have been due to immunization by blood-type A antigen, with the human immunoglobulin products given to the patient being the source of the antigen. Administration of human immunoglobulin products to recipients of ABO-incompatible kidney transplants should be avoided, because it may cause an unexpected increase in anti-blood-type antibody titer.     

ABO-incompatible deceased donor liver transplantation with the use of antigen-specific immunoadsorption and anti-CD20 monoclonal antibody

In patients with fulminant liver failure requiring emergency liver transplantation, the only donor organ that becomes available may be ABO incompatible. The risk of graft failure because of antibody-mediated acute rejection is high, but can be reduced by various means. We reported a deceased donor ABO-incompatible liver allograft recipient who was treated with antigen-specific immunoadsorption in combination with anti-CD20 monoclonal antibody and conventional plasmapheresis and immunosuppression. The patient was a 33-yr-old male with blood group A who presented with subacute liver failure of unknown aetiology and received a blood group AB liver graft. Pretransplant he underwent plasmapheresis and received one dose of rituximab. The immunosuppressive regimen consisted of methylprednisolone, tacrolimus and mycophenolate mofetil. Despite regular post-operative plasmapheresis sessions, anti-B antibody titres increased. Antigen-specific immunoadsorption with depletion of anti-B antibodies was performed from day nine to day 17. Thereafter, anti-B IgM and IgG antibody titres remained low. After one month the patient was reoperated with hepaticojejunostomy because of bile duct necrosis and with reconstruction of a stenotic hepatic artery. A mild rejection was successfully treated with methylprednisolone four months post-transplant. At six months post-transplant there was a stricture of the biliary-enteric anastomosis, but the graft was well functioning. We conclude that antigen-specific immunoadsorption can be an important adjuvant therapy to control recipient anti-A/B antibody levels and prevent acute rejection in ABO-incompatible deceased donor liver transplantation.     

Adult ABO-incompatible liver transplantation, using A and B donors

BACKGROUND: The longer waiting time for a liver graft in patients with blood group O makes it necessary to expand the donor pool for these patients. This applies in both urgent situations and for elective patients. We report on our experience with ABO-incompatible liver transplantation using A2 and B non-secretor donors here. PATIENTS AND METHODS: Between 1996 and 2005, 12 adult blood group O recipients (seven male/five female) received ABO-incompatible cadaveric liver grafts (10 A2 donors, two B non-secretor donors). The indications were either rapid deterioration of liver function or hepatocellular cancer, in blood group O recipients, where an ABO-identical/compatible graft was not available. Mean recipient age was 54+/-8 (mean+/-SD) yr. All pre-operative CDC crossmatches were negative. The initial immunosuppression was induction therapy with antithymocyte globulin (n = 3), interleukin 2 receptor antagonists (n = 3) or anti-CD20 antibody (rituximab) (n = 1), followed by a tacrolimus-based protocol. Three patients underwent plasmapheresis post-transplantation. Baseline biopsies were taken before or immediately after reperfusion of the graft and after grafting when clinically indicated. No pre-operative plasmapheresis, immunoadsorption or splenectomies were performed. RESULTS: Patient and graft survival was 10/12 (83%) and 8/12 (67%), respectively, with a 6.5-month median follow-up (range 10 days to 109 months). Two patients (B non-secretor grafts) died of multiorgan failure probably because of a poor condition before transplantation. Three patients were retransplanted. Causes of graft loss were bacterial arteritis (n = 1), death with a functioning graft (n = 1) and portal vein thrombosis (n = 2). In one of the patients with portal vein thrombosis, an anti-A titer increase occurred concomitantly, and ABO incompatibility as the cause of the thrombosis cannot be excluded. Seven acute rejections occurred in five patients and all were reversed by steroids or increased tacrolimus dosage. The pre-transplant anti-A titers tested against A1 red blood cells were 1 to 128 (NaCl technique) and 4 to 1024 (indirect antiglobulin technique, IAT); the maximum postoperative titers were 16 to 2048 (NaCl) and 256 to 32,000 (IAT). CONCLUSION: The favorable outcome of A2 to O grafting, with a patient survival of 10/10 and a graft survival of 8/10, makes it possible to also consider this blood group combination in non-urgent situations. The use of non-secretor donor grafts is interesting but has to be further documented. There was no hyperacute rejection or increased rate of rejection. Anti-A/B titer changes seem not to play a significant role in the monitoring of ABO-incompatible liver transplantation.     

Long-term outcome of ABO-incompatible renal transplantation.

Based on the long-term experience with ABO-incompatible kidney transplantation, the following can be concluded: 1. Renal transplantation across ABO incompatibility is an acceptable treatment for patients with end-stage renal failure. [table: see text] 2. Long-term patient and graft survival in ABO-incompatible kidney transplantation is influenced primarily by acute rejection episodes occurring within 1 year. 3. Despite the removal of anti-ABO natural antibodies before transplantation, hyperacute rejection crises may occur in some cases. 4. Humoral rejection is the most prominent type of rejection in ABO-incompatible renal transplantation. Even though most of this rejection is controllable with anti-rejection therapy, the prognosis for a graft that undergoes humoral rejection is significantly poor. 5. The maximum IgG titers of anti-A/B antibody before transplantation may have a harmful effect on graft acceptance in ABO-incompatible kidney transplantation. 6. Renal transplantation across ABO incompatibility is principally the most significant risk factor to affect long-term allograft function in ABO-incompatible living kidney transplantation.