Passenger lymphocyte syndrome (PLS) is most commonly observed after solid organ transplantation with minor ABO blood group incompatibility. It consists of a set of clinical symptoms brought on by the remaining lymphocytes of the donor organ developing antibodies against the recipient\'s antigens. Here, we describe a typical case of PLS in a type A+ recipient receiving a liver transplant from a type O+ donor. She suffered from jaundice, abnormally decreased hemoglobin level, and severe hemolytic anemia without bleeding. During hemolysis, we detected a positive direct antiglobulin test (DAT), and the thermal elution test revealed the presence of IgG anti-A antibodies in her serum. When immunosuppressive agents and blood transfusion were used together, cross-matched O+ washing red blood cells led to an expected outcome without side effects.

ABO incompatibility is not considered a contraindication for hematopoietic stem cell transplantation (HSCT). Approximately 30% of transplants from related donors and up to 50% of transplants from unrelated donors are ABO incompatible. Immuno-hematologic investigations allow to estimate donor/recipient ABO mismatch and anti-A/B isohemagglutinin (IHA) titration in the pre-HSCT phase. Immediate hemolysis or delayed complications (passenger lymphocyte syndrome and pure red cell aplasia) can occur post HSCT. Some preventive measures take into consideration either decision-making algorithms based on the recipient\'s IHA titration or clinical protocols for the removal/reduction of IHAs through plasma exchange or immunoadsorption procedures. Product manipulation through red blood cell (RBC) and/or plasma depletion can also be taken into account. Currently, the best approach in the management of ABO-incompatible transplant is not defined in expert consensus documents or with solid evidence. In addition, the methods for IHA titration are not standardized. A transfusion strategy must consider both the donor\'s and recipient\'s blood group systems until the RBC engraftment catches on and ABO conversion (forward and reverse typing) is confirmed on two consecutive and independent samples. Therefore, ABO incompatibility in HSCT represents a demanding immuno-hematologic challenge and requires all necessary preventive measures, including the appropriate selection of ABO blood components for transfusion.

Neonatal hyperbilirubinemia is a common concern in newborns, with ABO blood group incompatibility serving as a significant risk factor for severe jaundice. This case report outlines the successful management of a 2.5 kg female infant born to a primigravida mother with ABO incompatibility-induced hyperbilirubinemia. The neonate, born at 38.4 weeks via lower segment cesarean section, exhibited signs of jaundice at 91 hours of life, prompting screening and subsequent confirmation of serum bilirubin levels 26.4. The decision was made using the American Academy of Pediatrics (AAP) and categorized the child under high risk according to age and bilirubin level to implement a complete exchange transfusion using a novel approach with two infusion pumps. The unique aspect of this case lies in introducing a two-infusion pump technique, one to infuse and one to extract blood by inserting the IV set in opposite directions in the infusion pump to perform the exchange transfusion, aiming to minimize complications associated with traditional methods. Careful handling of umbilical venous and arterial lines, coupled with aseptic precautions, sought to mitigate the risk of sepsis. The procedure, conducted over two hours, demonstrated stability in vital signs and was monitored with a transcutaneous bilirubinometer. Post-transfusion, repeat serum bilirubin tests showed a decrease in bilirubin of 10.1, indicating the success of the novel exchange transfusion method. The infant was discharged after a five-day hospital stay, showcasing this innovative approach\'s potential efficacy and safety. This case contributes to the evolving strategies in neonatal care and emphasizes the importance of tailored interventions in managing hyperbilirubinemia associated with ABO incompatibility.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) has emerged as a curative measure for life-threatening hematological disorders. It can be autologous or allogeneic depending on the disease characteristics. Providing transfusion support to the transplant patients can be challenging, especially in AB-mismatched allogeneic HSCT. In this study, we investigated the impact of ABO incompatibility in patients undergoing allogeneic HSCT.
METHODS: A retrospective review was conducted in 76 patients with hematological diseases who underwent allogeneic HSCT. Transfusion requirements, engraftment profile, incidence of graft versus host disease (GvHD), and mortality for a period of 1 year were analyzed.
RESULTS: ABO incompatibility between donor and the patient did not significantly affect the neutrophil and platelet (PLT) engraftment time (P = 0.389, 0.349, respectively), packed red blood cells transfusion requirement, and duration of initial hospital stay. However, patients of ABO-incompatible HSCT received more PLT transfusions posttransplant which was statistically significant. 29.1% of ABO compatible and 16.7% incompatible HSCT patients developed GVHD. Mortality rates in the two groups were 16.7% and 8.3%, respectively. However, differences in both the parameters were not statistically significant.
CONCLUSIONS: Our study showed that ABO incompatibility does not significantly affect the outcome and should not be a limiting factor for selection of donor. Donor availability and human leukocyte antigen (HLA) matching remain the critical selection criteria.

UNASSIGNED: With the improvement of immunosuppressive regimens, the success rate and availability of ABO-incompatible (ABO-i) kidney transplantation (KT) have gradually increased. However, the management of immunosuppression protocols and complications associated with ABO-i KT is complex. Here, we report a clinical case of ABO-i living donor KT with allograft dysfunction caused by acute blood group antibody-dependent rejection triggered by human parvovirus B19 (B19V).
UNASSIGNED: The ABO blood group of the recipient was O, and that of the donor was B. The recipient had high baseline anti-B antibody titers (IgM, 1:1024; IgG, 1:64). Before transplantation, he completed a desensitization protocol comprising plasma exchange, double-filtration plasmapheresis, and rituximab, which maintained a low blood group antibody level and resulted in successful transplantation. Two weeks after surgery, the recipient developed a B19V infection combined with acute T-cell-mediated rejection. After the anti-rejection regimen, acute rejection (AR) was successfully reversed, but B19V persisted. One week after AR stabilization, the patient experienced acute antibody-mediated rejection that was more severe and refractory, resulting in the loss of the transplanted kidney.
UNASSIGNED: Desensitization combined with immunosuppressants can lead to overimmunosuppression and cause various infections. Infections could break the accommodation state of the patient, thereby inducing AR and resulting in the loss of the transplanted kidney.

Background and objective Allogeneic hematopoietic stem cell transplantation (alloHSCT) provides curative treatment for several hematological illnesses. In this study, we evaluated the impact of ABO compatibility and incompatibility on outcomes and complications related to hematopoietic stem cell transplantation (HSCT) performed for various hematological disorders at our center. Methodology This was a retrospective, single-center, cohort study in which patients were categorized according to the ABO match and mismatch status. The mismatch group was further subcategorized into major, minor, and bidirectional groups. Results A total of 117 patients underwent alloHSCT, out of which 82 (70.1%) were male and 35 (30%) were female. The median age of the patients was 9.5 years (range: 46 years). The most common indications for stem cell transplant were beta-thalassemia major (BTM; n=58, 49%) and aplastic anemia (AA; n=42, 35.8%). However, the outcomes in match and mismatch groups showed significant results for positive direct Coombs test (DCT), indicating the occurrence of hemolysis. Despite the increased need for blood transfusions, ABO blood group incompatibility (ABOi) had no negative impact on the clinical results. Conclusion Based on our findings, ABO incompatibility does not affect the outcomes in patients undergoing alloHSCT. Patient monitoring can aid in early detection and treatment, thereby minimizing the frequency of fatal events.

ABO incompatibility between O blood group mother and non-O blood group neonate is common. It rarely causes anemia and hyperbilirubinemia in neonate, requiring invasive management. Direct antiglobulin test may be positive in these cases with immunoglobulin (Ig)-G antibody specificity. There are few cases of hemolytic disease of newborn due to ABO incompatibility between mother and newborn with non - O blood group mother. After obtaining consent from the patient, we reported a case of incompatibility in a B blood group mother and A blood group neonate, and it was managed with phototherapy.

Background The immunoglobulin G of mothers with O blood type may sensitize the platelets of their neonates with A (O-A incompatibility) or B (O-B incompatibility) blood type. As the expression and antigenicity of the B antigen on platelets is less than that of the A antigens, we have hypothesized that platelet count is higher in the O-B incompatibility group compared to the O-A incompatibility group. There is controversy about whether glucose-6-phosphate dehydrogenase (G6PD) deficiency, without evidence of hemolysis, is associated with a lower platelet count than G6PD-normal. Aim To assess whether platelet count is higher in the O-B than in the O-A incompatible neonates and whether it correlates with their G6PD levels. Methods This study was a retrospective cohort study on a sample of 835 healthy neonates born at ≥38 weeks gestation who were either A or B blood types with mothers that carried the blood type O Rh-positive. The platelet count (thousand per microliter) from umbilical cord venous blood (UCVB) was used. A G6PD level of 11.0 units/gram of hemoglobin (U/g Hb) was considered the lower reference limit. G6PD deficiency was defined as a G6PD level of <3.3 U/g Hb in both sexes. Intermediate G6PD deficiency in females was described as a G6PD level of 3.3-8.8 U/g Hb. Results The mean UCVB platelet count was higher in female neonates compared to male neonates (n=389, 283±65 versus n=446, 272±73, p=0.01). The mean UCVB platelet count was higher in the O-B incompatibility group in both male (n=114, 291±82 versus n=103, 266±63) and female neonates (n=83, 303±66 versus n=81, 278±58) with G6PD levels of >8.8 U/g Hb. There was a positive weak correlation between UCVB platelet counts and G6PD levels only in O-B incompatible female neonates (n=176, r=0.23, p=0.002). The partitioning and combined 95% reference intervals (RIs) of the UCVB platelet count were presented. Conclusion The platelet count was higher in the O-B incompatibility group compared to the O-A incompatibility group, but only when the G6PD level was >8.8 U/g Hb. A correlation between UCVB platelet count and G6PD levels was found only among O-B incompatible female neonates. These findings may have an important implication in estimating RIs of the UCVB platelet count, however, they need to be confirmed and explored in future research.

Allogeneic hematopoietic stem cell transplantations (HSCTs) represent a curative strategy for treating hematologic malignancies yet bear dangerous and frequently life-threatening complications including the development of graft-versus-host disease. Here, we present a case of a patient that suffered from relapsed/refractory multiple myeloma, a hematologic neoplasm characterized by clonal proliferation of malignant plasma cells in the bone marrow. During the course of his disease, the patient underwent consecutive allogeneic HSCTs, during which he developed a clinical meaningful and hitherto unreported ABO subgroup incompatibility, leading to persistent hemolysis. Testing for ABO subgroups during donor selection, especially after consecutive allogeneic HSCTs, may therefore aid to prevent these complications.

UNASSIGNED: Intravenous immunoglobulin (IVIG) has been widely used to treat the hemolytic disease of the newborn (HDN). Although it has been shown that IVIG treatment reduces the duration of phototherapy and hospitalization, the use of IVIG in hemolytic disease due to ABO incompatibility has been controversial in recent years. This study aimed to investigate the role of IVIG in the prevention of exchange transfusion in infants with ABO HDN who presented with bilirubin levels at or above the level of exchange transfusion.
UNASSIGNED: This study evaluated the data of infants with ABO HDN in the Turkish Neonatal Jaundice Online Registry. The infants with ABO HDN who met the total serum bilirubin level inclusion criteria (within 2-3 mg/dL of exchange transfusion or even above exchange transfusion level) were included in the study according to the guidelines from the American Academy of Pediatrics and the Turkish Neonatal Society. All patients were managed according to the unit protocols recommended by these guidelines and received light-emitting diode (LED) phototherapy. Infants who only received LED phototherapy, and who received one dose of IVIG with LED phototherapy were compared.
UNASSIGNED: During the study period, 531 term infants were included in the study according to inclusion criteria. There were 408 cases in the phototherapy-only group, and 123 cases in the IVIG group. The demographic findings and the mean bilirubin and reticulocyte levels at admission were similar between the groups (p > 0.05), whereas the mean hemoglobin level was slightly lower in the IVIG group (p = 0.037). The mean age at admission was earlier, the need for exchange transfusion was higher, and the duration of phototherapy was longer in the IVIG group (p < 0.001, p = 0.001, and p < 0.001, respectively). The rate of re-hospitalization and acute bilirubin encephalopathy (ABE) was higher in the IVIG group (p < 0.001 and p = 0.01, respectively).
UNASSIGNED: In this study, we determined that one dose of IVIG did not prevent an exchange transfusion nor decrease the duration of phototherapy in infants, who had bilirubin levels near or at exchange transfusion level, with hemolytic disease due to ABO incompatibility.