Rituximab administration one week before ABO-incompatible liver transplantation due to drug-induced acute liver failure with hepatic coma: a case report.

In cases of acute liver failure (ALF) with hepatic coma, early liver transplantation, including ABO-incompatible (ABOi) living donor liver transplantation (LDLT), should be considered. The ABO antibody barrier can be reduced using plasma exchange (PE) and the anti-CD20 antibody rituximab. Plasma exchange is also performed for drug-induced ALF and is effective for desensitization. Rituximab treatment usually requires 14 days. There is presently no established desensitization protocol for ABOi-LDLT for ALF. Here, we report a case of drug-induced ALF with hepatic coma, which was treated with ABOi-LDLT using PE and rituximab 8 days prior to surgery. A 33-year-old female, with a history of headaches for which she was taking analgesics daily, developed drug-induced ALF with hepatic coma. Her ABOi sister desired to become a liver donor. We initiated desensitization using rituximab (500 mg) and mycophenolate mofetil (MMF, 2000 mg/day), followed by five sessions of PE. Eight days after rituximab administration, ABOi-LDLT with splenectomy was performed. Postoperatively, the patient received local infusion via portal vein for 14 days and immunosuppression with tacrolimus, methylprednisolone, and MMF. No episode of cellular or antibody-mediated rejection (AMR) was observed. The patient was discharged uneventfully 56 days after ABOi-LDLT with no problems up to 15 months after the transplant.

Large volume plasmapheresis using a single-use immunoadsorption column: A cost-effective approach for desensitization in ABO-incompatible liver transplant.

INTRODUCTION: Liver transplant is a life-saving treatment, but due to the limited availability of suitable liver donors, ABO-incompatible liver transplants (ABOi-LT) are conducted to increase the availability of liver donors. Perioperative desensitization for ABOi-LT is an established strategy to circumvent the risk of graft rejection. A single prolonged session can be performed to achieve the desired titers to avoid using multiple immunoadsorption (IA) columns or off-label reuse of single-use columns. This study retrospectively assessed the effectiveness of a single prolonged plasmapheresis session using IA as a desensitization strategy in live donor liver transplant (LDLT). MATERIALS AND METHODS: This retrospective observational study conducted at a center for liver diseases in North India on six ABOi-LDLT patients who underwent single prolonged IA sessions in the perioperative period from January 2018 to June 2021. RESULTS: Median baseline titer in patients was 320 (64, 1024). The median plasma volume adsorbed was 7.5 volumes (4, 8) per procedure, with a mean procedure time of 600 min (310-753). The reduction in titer ranged from 4 log to 7 log reduction per procedure. Two patients developed transient hypotension during the procedure, which was managed successfully. The median duration of pre-transplant hospital stay was 1.5 days (1, 3). CONCLUSION: Desensitization therapy helps overcome the ABO barrier and decreases the waiting period before a transplant when ABO identical donors are unavailable. A single prolonged IA session reduces the cost of additional IA columns and hospital stay, thus making it a cost-effective approach to desensitization.

Successful treatment of pure red cell aplasia using therapeutic plasma exchange after ABO-incompatible hematopoietic stem cell transplant.

Hematopoietic stem cell transplants (HSCTs) are widely used in the treatment of hematologic malignancies and bone marrow failure syndromes. ABO compatibility is typically of secondary importance, and up to 50% of HSCT are performed in ABO-incompatible pairings. In the literature, pure red cell aplasia (PRCA) occurs in 1% to 50% of all major/bidirectional ABO-incompatible stem cell transplants, but treatment of PRCA remains heterogeneous. Here, we report two cases in which patients with transfusion-dependent PRCA following HSCT were successfully treated with therapeutic plasma exchange (TPE). Case 1: A 52-year-old type O-positive male with acute myeloid leukemia underwent HSCT using apheresis-derived HSCs from a fully human leukocyte antigen (HLA)-matched, related type A-positive male donor. He developed PRCA that was refractory to multiple therapies, so a series of 10 TPE was performed over 3 weeks. Case 2: A 21-year-old type A-positive male with aplastic anemia underwent HSCT using bone marrow-derived HSCs from a fully HLA-matched related type B-positive female donor. He developed PRCA that was refractory to multiple therapies, so a series of 5 TPE was performed over 2 weeks. Case 1: The patient has been transfusion independent since TPE #7, and type A red blood cells (RBCs) were seen on the ABO type after TPE #9. Case 2: The patient has been transfusion independent since after TPE #1, and type B RBCs were seen on the ABO type after TPE #5. TPE was successful in treating two patients with PRCA after ABO-incompatible HSCT transplants. Isoagglutinin titers decreased below the level of detection for both our patients. Ultimately both patients became transfusion independent and showed evidence of erythroid cell recovery.

Intraoperative anti-A/B immunoadsorption is associated with significantly reduced blood product utilization with similar outcomes in pediatric ABO-incompatible heart transplantation.

BACKGROUND: Intraoperative anti-A/B immunoadsorption (ABO-IA) was recently introduced for ABO-incompatible heart transplantation. Here we report the first case series of patients transplanted with ABO-IA, and compare outcomes with those undergoing plasma exchange facilitated ABO-incompatible heart transplantation (ABO-PE). METHODS: Data were retrospectively analysed on all ABO-incompatible heart transplants undertaken at a single centre between January 1, 2000 and June 1, 2020. Data included all routine laboratory tests, demographics and pre-operative characteristics, intraoperative details and post-operative outcomes. Primary outcome measures were volume of blood product transfusions, maximum post-transplant isohaemagglutinin titres, occurrence of rejection and graft survival. Secondary outcome measures were length of intensive care and hospital stay. Demographic and survival data were also obtained for ABO-compatible transplants during the same time period for comparison. RESULTS: Thirty-seven patients underwent ABO-incompatible heart transplantation, with 27 (73%) using ABO-PE and 10 (27%) using ABO-IA. ABO-IA patients were significantly older than ABO-PE patients (p < 0.001) and the total volume of blood products transfused during the hospital admission was significantly lower (164 [126-212] ml/kg vs 323 [268-379] ml/kg, p < 0.001). No significant differences were noted between methods in either pre or post-transplant maximum isohaemagglutinin titres, incidence of rejection, length of intensive care or total hospital stay. Survival comparison showed no significant difference between antibody reduction methods, or indeed ABO-compatible transplants (p = 0.6). CONCLUSIONS: This novel technique appears to allow a significantly older population than typical to undergo ABO-incompatible heart transplantation, as well as significantly reducing blood product utilization. Furthermore, intraoperative anti-A/B immunoadsorption does not demonstrate increased early post-transplant isohaemagglutinin accumulation or rates of rejection compared to ABO-PE. Early survival is equivalent between ABO-IA, ABO-PE and ABO-compatible heart transplantation.

Feasibility of Immunoadsorption plasmapheresis in an infant for ABO-incompatible solid organ transplant-A reality.

BACKGROUND: Immunoadsorption (IA) plasmapheresis is standard modality for pretransplant desensitization in ABO-incompatible solid organ transplants though technically challenging when considered for an infant or a child less than 10 kg due to non-availability of pediatric immunoadsorption (IA) columns. The major challenge is to maintain hemodynamic stability considering the large extracorporeal circuit volume meant for adults. To our best knowledge after extensive search in acclaimed global medical journals, this is the first successful attempt in an underweight (6 kg) infant of less than 1 year of age using adult size IA Column thus making it a reality. CASE CHARACTERISTICS: We report an 8-month-old male infant (A positive) of 6 kg with decompensated liver disease secondary to extrahepatic biliary atresia requiring urgent live donor liver transplantation with AB positive donor with significantly elevated pretransplant anti-B IgG/ IgM antibody titers >1:1024. Baby underwent multiple sessions of anti-B immunoadsorption plasmapheresis to lower anti-B IgM / IgG titers using available adult anti-B immunoadsorption column. Postprocedure, the antibody titers reduced to 1:8 (anti-IgG) 1:16 (anti-IgM) followed by successful ABO-incompatible live donor liver transplant (LDLT). OUTCOME: Anti-B titers remained in normal range in the immediate and post-transplant period with satisfactory liver functions and no rejection. CONCLUSION: Immunoadsorption plasmapheresis for ABO-incompatible solid organ transplantation in infants gives desirable results and can be offered to small sized infants using currently available adult sized IA columns when conducted with adequate technical expertise.

Evaluation of safety of using incompatible plasma for therapeutic plasma exchange during shortage of AB plasma.

BACKGROUND: Criteria for selection of FFP blood type has not been clearly established and use of group AB plasma is preferred by numerous transplantation protocols. AIMS: This study assesses the safety and efficacy of alternative group A or B plasma in ABO incompatible solid organ transplantation. MATERIALS & METHODS: Alternative use of group A or B plasma (incompatible plasma) was inevitable during the shortage of group AB plasma. Experience from select number of patients during the period of extreme group AB plasma shortage is described. RESULTS: The result of alternative use of group A or B plasma was within expectation, showing effective reduction of isoagglutinin titers for pre-operative desensitization and efficacy for treatment of post-operative patients. No immediate hemolytic transfusion reaction was reported. DISCUSSION: While validation in a larger cohort of patients is necessary, our limited experience have shown satisfactory clinical outcomes without adverse events. CONCLUSIONS: Use of incompatible group A or B plasma is a viable option when group AB plasma is limited.

Selective ABO immunoadsorption in hematopoietic stem cell transplantation with major ABO incompatibility.

OBJECTIVE: ABO mismatch between donor and recipient occurs in 40% of allogeneic hematopoietic stem cell transplantations (HCT). Different strategies have been described to reduce isohemagglutinins (IHA) before HCT. We describe the effect of selective ABO immunoadsorption (ABO IA) on erythrocyte transfusion rate and the development of post-transplant pure red cell aplasia (ptPRCA). METHODS: 63 patients with major ABO incompatibility were retrospectively analyzed. Nine patients with major ABO incompatibility and high-IHA titer were treated by ABO IA before HCT. We analyzed the need for transfusion and the occurrence of ptPRCA. We compared the outcome with patients treated by other methods to reduce IHA. RESULTS: In all nine patients treated by ABO IA, IHA decreased in a median four times. PtPRCA occurred in one patient. The median number of transfusions was 8 (range: 0-36) between d0 and d100. In 25 patients with high-IHA titer without treatment or treated by other methods to reduce IHA, the need for transfusions was comparable. No difference in the incidence of ptPRCA was observed. CONCLUSIONS: Selective ABO IA is a feasible, safe, and effective method to reduce IHA before HCT in major ABO incompatibility. No effect on transfusion rate or ptPRCA compared to other strategies could be observed.

Removal of Anti-Thymocyte Globulin by Plasma Exchange in ABO-Incompatible and Positive Crossmatch Kidney Transplant Recipients.

BACKGROUND: Recipients of ABO-incompatible (ABOI) and positive crossmatch (PXM) kidney transplants are at high risk for antibody-mediated acute rejection. Despite aggressive immunosuppression in high-risk patients, the incidence of acute rejection remains considerably higher than in other groups. No published studies have examined plasma concentrations of anti-thymocyte globulin (ATG) in patients undergoing plasma exchange. The objectives of this study were to compare plasma ATG concentrations before and after plasma exchange in ABOI and PXM kidney transplant patients to determine the amount removed. MATERIALS AND METHODS: This prospective pharmacokinetic evaluation enrolled 10 patients undergoing ABOI or PXM kidney transplant at an academic medical center. Blood and waste plasma samples from 5 patients were assayed for total and active ATG concentrations. Patient records were monitored for renal function and rejection rates in the first 6 months post-transplant. RESULTS: Total ATG concentrations decreased a mean of 59.78 ± 13.91% after each plasma exchange session, and active ATG levels decreased a mean of 56.8 ± 17.08%. Mean daily concentrations reflect a lack of expected ATG accumulation. Only 1 of 4 patients had detectable ATG concentrations after 30 days. After 6 months, the incidence of acute rejection in this sample was 44% and graft survival was 89%. CONCLUSIONS: This is the first study to show that plasma exchange removes a substantial amount of ATG in high-risk kidney transplant patients. Based on these results, we believe these high-risk patients have been traditionally underdosed.

Clinical consequences of the extremely rare anti-PP1Pk isoantibodies in pregnancy: a case series and review of the literature.

BACKGROUND: The absence of the red cell antigens P, P1 and Pk , known as 'p', represents an extremely rare red cell phenotype. Individuals with this phenotype spontaneously form anti-PP1Pk isoantibodies, associated with severe haemolytic transfusion reactions, recurrent spontaneous abortion and haemolytic disease of the fetus and newborn (HDFN). METHODS: We report a series of four successful pregnancies in three women with anti-PP1Pk isoantibodies, one complicated by HDFN, another by intrauterine growth restriction, all managed supportively. We also review the literature regarding the management of pregnancy involving anti-PP1Pk isoimmunization. RESULTS: The literature surrounding anti-PP1Pk in pregnancy is limited to a very small number of case reports. The majority report management with therapeutic plasma exchange (TPE) with or without intravenous immunoglobulin. The relationship between titre and risk of pregnancy loss remains unclear, though a history of recurrent pregnancy loss appears important. Although a positive cord blood direct antiglobulin test is frequently noted, clinically significant HDFN appears uncommon, though possible. CONCLUSION: Early initiation of TPE in high risk patients should be strongly considered. If possible, pregnancies should be managed in a high-risk obstetric or maternal fetal medicine service. The fetus should be monitored closely with interval fetal ultrasound and middle cerebral artery peak systolic volume Doppler to screen for fetal anaemia. Timely sourcing of compatible blood products is likely to be highly challenging, and both directed and autologous donation should be contemplated where appropriate. The International Red Cell Donor Panel may also provide access to compatible products.

ABO-incompatible pediatric kidney transplantation without antibody removal.

BACKGROUND: Because of the severe shortage of suitable deceased donors, ABO-incompatible living donor kidney transplantation (ABOi LDKT) is performed even in pediatric recipients in Japan. We performed pediatric ABOi LDKT using rituximab without anti-A/B antibody removal. METHODS: Thirteen pediatric recipients (mean age 7.4, range 3.4-15.7, four females) whose baseline anti-A/B IgG titers were ≤ × 64 underwent ABOi LDKT without antibody removal and splenectomy between July 2013 and April 2017 at Toho University. Mycophenolate mofetil (MMF) was initiated on day - 10. Rituximab (100 mg) was administered twice. Basiliximab and triple maintenance immunosuppression (calcineurin inhibitor, MMF, and steroids) were administered. Protocol biopsy was performed at 3 months and 1 year after transplantation. We retrospectively compared the clinical outcomes between these recipients and 37 children (mean age 9.0, range 2.6-18.9, 15 female) who underwent ABO-compatible (ABOc) LDKT during the same period. RESULTS: The mean follow-up periods of ABOi and ABOc groups were 31.9 ± 13.5 and 28.8 ± 14.4 months, respectively. In the ABOi group, no clinical acute rejection (AR) was noted and subclinical AR was observed in four patients without evidence of acute antibody-mediated rejection. In the ABOc group, clinical and subclinical AR developed in 3 and 10 patients, respectively. No significant difference was identified for the mean eGFR between the ABOi and ABOc groups (98.3 ± 48.8 vs. 86.9 ± 39.4, P = 0.452 at 3 months; 78.2 ± 21.2 vs. 79.7 ± 21.3, at 1 year, P = 0.830). Death-censored graft survival at follow-up was 100% in the ABOi group and 94.6% in the ABOc group. Patient survival during the follow-up period in both the groups was 100%. Late-onset neutropenia (LON) requiring granulocyte colony-stimulating factor occurred more frequently in the ABOi group than in the ABOc group (4 vs. 0 patients) (P < 0.001). CONCLUSIONS: Pre- and post-transplantation antibody removal is not a prerequisite for successful pediatric ABOi LDKT, at least in patients with a low anti-A/B IgG antibody titer. However, LON caused by rituximab should be monitored.

Association between response to rituximab and antibody-mediated rejection in ABO-incompatible living kidney transplantation.

OBJECTIVES: To examine the association of response to rituximab and the incidence of antibody-mediated rejection in preconditioning of rituximab and plasma exchange without post-transplant plasmapheresis in patients undergoing ABO-incompatible living kidney transplantation. METHODS: A total of 115 patients who underwent ABO-incompatible living kidney transplantation at Tokyo Women's Medical University Hospital, Tokyo, Japan, were divided into two groups based on the response to rituximab: good response (n = 75) or poor response (n = 40). The rituximab good response and poor response patients were defined as patients whose CD19+ cells were non-detected (0%) and detected on the day of transplantation (2-5 days, median 3 days, after rituximab administration), respectively. RESULTS: Rituximab response and anti-A/B blood antibody titer after plasmapheresis were significant risk factors for antibody-mediated rejection (P = 0.036, 0.045, respectively). The occurrence of antibody-mediated rejection was higher in the poor response group than in the good response group (22.5% vs 8.0%; P = 0.028). The 14-day, 3-month and 1-year cumulative incidence of antibody-mediated rejection was 2.7%, 5.3% and 8.0% in the good response group, and 17.5%, 20.0% and 22.5% in the poor response group after ABO-incompatible living kidney transplantation. The patient survival was not significantly different between the two groups. However, graft survival 1 month after transplantation was lower in the poor response group. There is no significant difference in graft function and in the incidence of complications, including infection, after transplantation between the two groups. CONCLUSIONS: Antibody-mediated rejection after ABO-incompatible living kidney transplantation was significantly associated with the response to rituximab in our preconditioning protocol.

Effectiveness of different immunoadsorption columns for anti-A/B antibody depletion.

OBJECTIVE: In recent studies, semi-selective compared to antigen-specific immunoadsorption (IA) columns showed comparable effectiveness in anti-A/B antibody removal before incompatible living donor kidney transplantation. Semi-selective columns allow a greater number of IA treatments at lower costs. They are also capable of removing potentially harmful human leukocyte antigen alloantibodies. Nevertheless, additional plasma exchange treatments are often necessary to reach the preoperative target titer, most likely due to an inadequate anti-A/B IgM antibody depletion. METHODS: We compared the effectiveness of immunoglobulin and anti-A/B antibody reduction by different semi-selective (Therasorb Ig-flex, Therasorb Ig-omni5, Immunosorba) and antigen-specific (Glycosorb) IA columns during the desensitization of 63 ABO-incompatible living donor kidney transplant candidates with a total of 375 IA treatments. Fifty-three patients were eventually transplanted. RESULTS: Total IgM reduction during the first IA treatment was significantly greater with the Therasorb Ig-omni5 compared to the Therasorb Ig-flex (mean: -71.3 vs -41.6; p = 0.001) or Immunosorba columns (mean: -71.3 vs -42.8; p = 0.03). During a median of 5.5-6 pre-transplant IA treatments, Therasorb Ig-flex and Therasorb Ig-omni5 columns were equally effective in the reduction of total IgM while both showed superior IgM reduction compared to the Immunosorba columns (Therasorb Ig-flex, mean: -81.2 vs -72.2; p = 0.01; Therasorb Ig-omni5, mean: -88.2 vs -72.2; p = 0.02). IgG reduction was not significantly different between groups. Likewise, anti-A/B IgM antibody reduction (titer Saline) during the first IA treatment was significantly greater with the Therasorb Ig-omni5 compared to the Therasorb Ig-flex (mean titer reduction: -1.9 vs -1.1; p = 0.02) and tended to be greater than with Immunosorba or Glycosorb columns. During a median of 5-6 pre-transplant IA treatments, overall anti-A/B IgM antibody reduction was significantly greater when IA was performed with the Therasorb Ig-flex (mean titer reduction: -3.8 vs -1.3; p < 0.001) or Therasorb Ig-omni5 (mean titer reduction: -4.3 vs -1.3; p = 0.01) compared to the Immunosorba columns with no differences compared to the Glycosorb columns. Again, anti-A/B IgG antibody reduction (titer Coombs) was not significantly different between groups. CONCLUSIONS: The semi-selective Therasorb Ig-omni5 device offers potential advantages in reducing total IgM as well as anti-A/B IgM antibodies.

Clinical Characteristics of Jra Alloimmunization in Pregnancy: A Case Series.

Only few studies have reported on Jra alloimmunization in pregnancy, and its clinical course remains unclear. We reviewed our cases to clarify the change in the peak systolic velocity of the middle cerebral artery (MCA-PSV) during pregnancy and the critical anti-Jra antibody titer to predict fetal anemia. We collected the data of pregnant women with anti-Jra antibody from two hospitals between 2010 and 2017. We extracted data on maternal information, number of intrauterine blood transfusions (IUT), trend of anti-Jra antibody titer, changes of MCA-PSV, and neonatal outcome. We had 16 cases. IUTs were performed in 6 fetuses with severe anemia between 27 and 32 weeks' gestation. The MCA-PSV did not increase more than 1.5 multiples of the median (MoM) after 32 weeks' gestation. No significant difference was found in the maximum titer between cases with IUT and those without IUT. All pregnancies but one delivered at term. No neonates developed severe anemia or jaundice. MCA-PSV did not increase higher than 1.5 MoM later during the pregnancy. A critical titer to predict fetal anemia did not exist. Spontaneous term delivery could be expected even in fetuses who underwent IUT before 32 weeks' gestation.

ABO-incompatible living-donor kidney transplantation: Study of 48 patients after desensitisation. / Trasplante renal de donante vivo ABO incompatible. Estudio de 48 pacientes tras desensibilización.

BACKGROUND: ABO-incompatible living-donor kidney transplantation was regarded as an absolute contraindication. However, it has been carried out for years with good outcomes. OBJECTIVE: Our aim was to show the results obtained with this technique in our hospital. METHODS: Forty-eight patients with a mean age of 50.9±10.9 years were included. Follow-up was 44.6±30.9 months. Conditioning: rituximab 375mg/m2, tacrolimus, mycophenolate mofetil or mycophenolate sodium, prednisone, plasmapheresis/immunoadsorption and intravenous immunoglobulin. Accepted IgG and IgM titres for transplantation:<1:8. RESULTS: Pre-process IgG titre 1:124±1:140, IgM titre 1:77±1:55. After 6±3 sessions, IgG decreased to<1:8 in 47 patients and to<1:16 in one. IgM was<1:8 in all cases. Twenty-four patients (50%) had haematoma, 7 re-intervention (14.6%), 29 (60%) required transfusion. At 5 years, acute rejection had occurred in 5 cases (8.7%), CMV infection in 9 (19.7%), BK viraemia in 5 (12.4%), post-transplant diabetes in 10 (23.4%) and lymphocele in 3 (6.4%). Patient survival was 97.1% at 5 years and graft survival 95.7% at one year and 93% at 5 years. Causes of graft loss: thrombosis (n=1); mixed rejection (n=1); and death (n=2). Serum creatinine levels were 1.4±0.4mg/dl at one and 3 years and 1.3±0.3mg/dl at 5 years. Proteinuria was 0.2±0.2g/24h at one, 3 and 5 years. CONCLUSIONS: ABO-incompatible living-donor kidney transplantation after conditioning with rituximab, plasmapheresis/immunoadsorption and immunoglobulins is a valid option offering excellent outcomes. There is a low incidence of acute rejection and no increase in infectious complications. An increased tendency for postoperative bleeding was found.

Massive transfusion associated with a hemolytic transfusion reaction: necessary precautions for prevention.

CASE REPORT: A 45-year-old male presented in severe hypovolemic shock after a thoracoabdominal gunshot wound. The massive transfusion protocol (MTP) was activated and the patient was taken to the operating room. His major injuries included liver, small bowel, and right common iliac vein. Hemorrhage was stopped and a damage control laparotomy was completed. He received a total of 113 blood products. During his postoperative course he received a group B blood transfusion on Hospital Days 2 and 7 based on incorrect blood typing late in his massive transfusion and repeat testing on Day 4. RESULTS: He succumbed to multiple organ failure on Day 8. MTPs are standard in most trauma centers during which universal donor red blood cells are initially used. As hemorrhage is controlled, the patient undergoes a complete type and cross according to blood banking protocols. These typing results are used to continue transfusions once the MTP is no longer needed. In contacting other blood banks servicing Level I trauma centers, the policy of when to switch from universal donor blood to crossmatched blood is variable. CONCLUSION: Our case illustrates a potential blood typing problem that had a disastrous outcome. We identified changes in policy that will make MTPs safer.

Kidney transplantation across minor ABO incompatibility: the use of A2 to B transplants.

PURPOSE OF REVIEW: On 4 December 2014, the new kidney allocation system (KAS) went into effect. As part of this system, UNOS approved for the first time a national system with a specific mechanism affording priority to allocate kidneys across so-called 'minor ABO incompatibility' from blood group A2 donors into blood group B recipients. This significantly increased the number of such transplants done and the opportunities to learn about the specifics of such transplants. RECENT FINDINGS: A2 to B transplants have been demonstrated to be well tolerated, effective, and cost-effective ways of addressing disparities in the allocation system. Further data about the use of anti-A titers and the limits to successful transplant have better defined the bounds of who can benefit from such transplants. SUMMARY: The success thus far with A2 to B transplants should increase comfort and acceptance of the allocation policy changes and we should see further increases in centers willing to use such transplants to better address inequalities in the system.

A comparison of two protocols for optimal red blood cell depletion using Sepax-2 device for ABO-major incompatible transplantation in adults.

PURPOSE OF THE STUDY: In ABO-incompatible bone marrow transplantation, an efficient depletion of red blood cells (RBC) within the graft is mandatory to avoid adverse events in transplanted patients. Using non therapeutic products, we evaluated the substitution of the standard density gradient-based separation (DGBS) over Ficoll-Paque with the use of an automated procedure intended for buffy coat only (SmartRedux software) introducing modifications within the settings to achieve a drastic reduction of the initial volume of the product. Both methods were conducted on the Sepax-2 device. SAMPLES AND METHODS: RBC depletion rates and CD34+ cells recoveries from eight procedures with SmartRedux software using "in-house" settings (method A) were compared to those obtained from four procedures using NeatCell software, an automated DGBS over Ficoll-Paque (method B). RESULTS: Median erythrocyte depletion of 95,4% (92,7%-99,0%) and 99,8% (99,0%-99,9%) were observed using methods A and B, respectively. Median residual RBC volumes in the final product were 19 mL (4,4 mL-31,2 mL) and 0,7 mL (0,4 mL-4,7 mL), respectively (p = 0,014). CD34+ cells recoveries of 90,9% (62,7%-102,1%) and 78,4% (64,1%-86,2%) were achieved for methods A and B. Median platelet depletion was 16,6% (10%-42,7%) and 89,8% (88,5%-92,4%) using methods A and B, respectively (p = 0,004). Processing duration was shorter using method A (168 ± 29 min) than method B (295 ± 21 min) (p = 0,004). CONCLUSION: Both methods achieved satisfactory erythrocyte depletion and CD34+ recovery. The use of Sepax-2 device in association with SmartRedux software could be extended to efficiently deplete RBC from large-volume BM in a raw instead of DGBS.

Unusual cause of severe neonatal hyperbilirubinaemia: a twin case.

We present twins born to the 31-year-old, multigravida mother, who were referred to our centre at 90 hours of life for severe hyperbilirubinaemia. Twin 1 had already received two double volume exchange transfusions at 55 and 83 hours of life, in view of the persistent rise in bilirubin despite receiving phototherapy. Twin 2 had received phototherapy and 1 packed red blood cell transfusion in view of the fall in haematocrit. Mother's blood group was B positive and that of both twins was O positive. Both the twins were started on intensive phototherapy and their serum bilirubin and haematocrit were evaluated. On investigation, a minor blood incompatibility was found. Double volume exchange transfusion was done for twin 2 at 100 hours of life in view of the rapid rise in serum bilirubin. Both the babies were monitored for their serum bilirubin and treated for sepsis and discharged after 15 days.