UNASSIGNED: Exchange transfusion (ET) is an effective treatment for acute bilirubin encephalopathy and extreme neonatal hyperbilirubinemia (ENH). It can reduce mortality and morbidity. This study aimed to investigate the trends and risk factors of ENH requiring ET in hospitalized neonates in Iran.
UNASSIGNED: A retrospective analysis of medical records of neonates who underwent ET due to ENH was conducted from 2011 to 2021, in Shiraz, Iran. Clinical records were used to gather demographic and laboratory data. The quantitative data were expressed as mean±SD, and qualitative data was presented as frequency and percentage. P<0.05 was considered statistically significant.
UNASSIGNED: During the study, 377 ETs were performed for 329 patients. The annual rate of ET decreased by 71.2% during the study period. The most common risk factor of ENH was glucose-6-phosphate dehydrogenase (G6PD) deficiency (35%), followed by prematurity (13.06%), ABO hemolytic disease (7.6%), sepsis (6.4%), Rh hemolytic disease (6.08%), and minor blood group incompatibility (3.34%). In 28.52% of the cases, the cause of ENH was not identified. 17 (5.1%) neonates had acute bilirubin encephalopathy, of whom 6 (35.29%) had G6PD deficiency, 6 (35.29%) had ABO incompatibility, and 2 (11.76%) had Rh incompatibility.
UNASSIGNED: Although the rate of ET occurrence has decreased, it seems necessary to consider different risk factors and appropriate guidelines for early identification and management of neonates at risk of ENH should be developed. The findings of the study highlighted the important risk factors of ENH in southern Iran, allowing for the development of appropriate prevention strategies.

OBJECTIVE: Sickle cell disease (SCD) is a common hereditary hemoglobin disorder worldwide. One of the main treatments for patients with SCD is the requirement for blood transfusions. Posttransfusion alloimmunization with red blood cell (RBC) antigens continues to be a major risk factor for SCD. The objective of this study was to determine the rate, nature, and risk factors of red cell alloimmunization among pediatric patients with SCD in our center and compare our results with published reports from Saudia Arabia SA, regional countries, and some international countries.
METHODS: A retrospective chart review of patients with SCD at King Abdulaziz Medical City-Jeddah, between 2008 and 2019 was performed. Demographic characteristics and transfusion histories were recorded. Blood samples were analyzed for alloimmunization using immunohematologic techniques.
RESULTS: In total, 121 patients were analyzed. Alloantibodies were detected in 21 patients (17.4%) and were mostly single in 15 patients (71.4%), anti-K (23.7%), anti-E (19.0%), and anti-S (9.5%). The other 6 patients (28.6%) had multiple alloantibodies, especially the combination of anti-C and anti-K (9.5%) and the combination of anti-C and anti-E (9.5%). Alloantibody levels were significantly higher in patients with frequent hospital admissions (>5 times annually), those who had an exchange blood transfusion, those younger than 3 years old, and those who received a larger number of blood units ( P ≤0.05).
CONCLUSIONS: The rate of RBC alloimmunization is determined and considered relatively low compared with that in other nations. Matching for extended RBC antigens to include ABO, RH (D, C, c, E, e), K, Fy a , Fy b , Jk a , and Jk b antigens in the screening panel for donors and recipients is highly recommended to ensure better transfusion practices and avoid transfusion-related complications.

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.

UNASSIGNED: blood transfusion remains an essential therapeutic intervention, but the occurrence of transfusion reactions makes its administration even more complex. Vigilant reporting of such reactions by recipients of blood products is essential for effective haemovigilance. This study aimed to determine the frequency and nature of transfusion reactions.
UNASSIGNED: conducted over five years (2017-2021) at the Haemovigilance Department of the Rabat Regional Blood Transfusion Centre, this retrospective study exploited incident forms notified by health establishments and data from the regional blood transfusion centre\'s computer system.
UNASSIGNED: from 1 January 2017 and 31 December 2021, the Rabat Regional Blood Transfusion Centre distributed 435,651 labile blood products to various healthcare establishments, which reported 191 transfusion reactions involving 191 patients. The median age of the patients was 44.3 years, with an overall cumulative incidence of transfusion reactions of 0.44 per 1000 labile blood products delivered. The predominant reactions were non-haemolytic febrile and allergic reactions, accounting for 41.36% and 35.60% respectively. Grade 1 reactions accounted for 87% of all reactions recorded. During the study period, three deaths were recorded, with ABO incompatibility and transfusion-related acute lung injury (TRALI) accounting for two and one case respectively. Transfusion reactions involving erythrocyte components were significantly more frequent than those involving platelet and plasma components.
UNASSIGNED: this study revealed a relatively low incidence of transfusion reactions (0.44%), dominated by non-haemolytic febrile and allergic reactions. Several levels of failure were identified, in particular under-reporting of reactions and inadequate training in transfusion practices and haemovigilance, as well as the need for an effective electronic transfusion reaction reporting system to facilitate reporting and identification of underlying problems and risk factors to improve the quality of transfusion care provided to patients.

BACKGROUND: The U.S. Centers for Disease Control and Prevention (CDC) has reported increasing rates of alpha-gal syndrome, an allergic response after meat ingestion (AGS). AGS has been associated with prior exposure to tick bites or other biologics characterized by a life-threatening immunoglobulin E (IgE)-mediated hypersensitivity to galactose-alpha-1,3-galactose (alpha-gal) an oligosaccharide structurally similar to the group B antigen on red blood cells (RBC) found in most non-primate mammalian meat and products derived from these mammals. In 2023, Transfusion reported 3 group O recipients of group B plasma in the Washington, D.C. metropolitan area with no history of meat allergy who had anaphylactic transfusion reactions compatible with AGS.
OBJECTIVE: We investigated allergic reactions in 2 additional patients who received ABO minor-incompatible blood products at 2 hospitals in the D.C. area during fall 2023.
METHODS: For both patients, a medical chart review was performed and IgE levels to alpha-gal were measured.
RESULTS: The first patient, a 64-year-old, O-positive patient status post heart transplant with no known allergies, was admitted with acute COVID-19 induced antibody-mediated transplant rejection and placed on extracorporeal membrane oxygenation (ECMO). While undergoing plasma exchange (PLEX) (50% albumin/50% fresh frozen plasma (FFP)), the patient tolerated 2 units of group O FFP and 1 unit of group A FFP before becoming hemodynamically unstable during transfusion of 1 unit of B-positive FFP. PLEX was stopped. The patient later died of sepsis from underlying causes. The second patient, a 57-year-old O-positive man with a history of melanoma and neuro fibromatosis type 1, was undergoing an abdominal resection including transfusion of 3 units of O-positive RBC when he suffered hypotension and ventricular tachycardia requiring intraoperative code after receiving 2 units of group B FFP. Hiveswere noted after resuscitation. The patient had a history of tick bites but no known allergies. He is alive 5 months after the possible allergic event. Both patients had full transfusion reaction evaluations and immunology testing results above the positive cutoff for anti-alpha-gal IgE.
CONCLUSIONS: Two patients with O-positive blood and no known allergies experience danaphyl axis after transfusion with group B FFP. The symptoms cannot definitively be imputed to an allergic transfusion reaction, but the presence of IgE against alpha-gal supports an association. Medicating patients with antihistamines and IV steroids pre-transfusion may prevent allergic reactions. Restricting group B plasma-containing products (plasma, platelets, cryoprecipitate) for patients who experience AGS-like symptoms may be considered.

ABO-incompatible (ABOi) living kidney transplantation (KTx) is an established procedure to address the demand for kidney transplants with outcomes comparable to ABO-compatible KTx. Desensitization involves the use of immunoadsorption (IA) to eliminate preformed antibodies against the allograft. This monocentric retrospective study compares single-use antigen-selective Glycosorb® ABO columns to reusable non-antigen-specific Immunosorba® immunoglobulin adsorption columns regarding postoperative infectious complications and outcome. It includes all 138 ABOi KTx performed at Freiburg Transplant Center from 2004-2020. We compare 81 patients desensitized using antigen-specific columns (sIA) to 57 patients who received IA using non-antigen-specific columns (nsIA). We describe distribution of infections, mortality and allograft survival in both groups and use Cox proportional hazards regression to test for the association of IA type with severe infections. Desensitization with nsIA tripled the risk of severe postoperative infections (adjusted HR 3.08, 95% CI: 1.3-8.1) compared to sIA. nsIA was associated with significantly more recurring (21.4% vs. 6.2%) and severe infections (28.6% vs. 8.6%), mostly in the form of urosepsis. A significantly higher proportion of patients with sIA suffered from allograft rejection (29.6% vs. 14.0%). However, allograft survival was comparable. nsIA is associated with a two-fold risk of developing a severe postoperative infection after ABOi KTx.

Passenger lymphocyte syndrome is an immunologic disorder observed in solid organ and haematopoietic stem cell transplantation in which B lymphocytes within a donor graft are transferred to the recipient and subsequently produce circulating antibodies against host red blood cell antigens. The syndrome is most likely to occur in minor ABO blood group mismatched or Rh incompatible transplantation. Although generally mild and self-limited, the resulting haemolytic burden has the potential to increase the risk of infection, graft failure and death. The phenomenon is observed in the transplantation of any solid organ with lymphoid tissue, including the liver. We present a structured case report of passenger lymphocyte syndrome following minor ABO-mismatched liver transplantation, which was initially complicated by blood loss anaemia early in the postoperative period. By reviewing the limited literature of this disorder following liver transplantation, we emphasise common clinical findings and treatment strategies as well as introduce chimerism analysis to confirm resolution.

BACKGROUND: Extracellular vesicles (EVs) have received considerable attention as ideal biomarkers for kidney diseases. Most reports have focused on urinary EVs, that are mainly derived from the cells in the urinary tract. However, the detection and the application of kidney-derived EVs in plasma remains uncertain.
METHODS: We examined the kidney-derived small EVs (sEVs) in plasma that were supposedly released from renal mesangial and glomerular endothelial cells, using clinical samples from healthy controls and patients with kidney transplants. Plasma from healthy controls underwent ultracentrifugation, followed by on-bead flow cytometry, targeting α8 integrin, an antigen-specific to mesangial cells. To confirm the presence of kidney-derived sEVs in peripheral blood, plasma from ABO-incompatible kidney transplant recipients was ultracentrifuged, followed by western blotting for donor blood type antigens.
RESULTS: Immunohistochemistry and immunoelectron microscopy confirmed α8 integrin expression in kidney mesangial cells and their sEVs. The CD9-α8 integrin double-positive sEVs were successfully detected using on-bead flow cytometry. Western blot analysis further revealed transplanted kidney-derived sEVs containing blood type B antigens in non-blood type B recipients, who had received kidneys from blood type B donors. Notably, a patient experiencing graft kidney loss exhibited diminished signals of sEVs containing donor blood type antigens.
CONCLUSIONS: Our findings demonstrate the potential usefulness of kidney-derived sEVs in plasma in future research for kidney diseases.

ABO-group major incompatibility hematopoietic stem cell transplantation (HSCT) increases the risk of delayed red cell engraftment and other immunological complications. In this study, we evaluated the efficacy of pre-transplant infusion of rituximab in patients with ABO-incompatibility in improving red blood cell engraftment after HSCT, measured by time to reach transfusion independence. We performed a retrospective, single-center study including 131 consecutive patients transplanted with major or bidirectional ABO-incompatible grafts between 1st January 2013 and 31st December 2019. Fifty-one patients received an infusion of rituximab during the conditioning regimen, while 80 patients did not receive any additional preventive treatment. Time to transfusion independence was significantly reduced for patients treated with rituximab (1 month, 95% CI, 0.5-2) compared with the control group (3.2 months, 95% CI 1.5-3.2, p = 0.02). By multivariable analysis, rituximab use was associated with a faster red blood cell (RBC) engraftment (RR 1.88, 95% CI 1.17-3.03, p = 0.009), while a pre-transplant anti-donor isohemagglutinins titer >1:128 was associated with delayed transfusion independence (RR 0.61, 95% CI 0.37-0.99, p = 0.05). Although limited by the retrospective nature of the study, the results of this analysis suggest that rituximab added to conditioning regimens is feasible, safe, and able to improve post-transplant red blood cell engraftment.

BACKGROUND The use of ABO-incompatible liver transplants (ABO-ILTs) from deceased donors has become more common due to the shortage of available donor livers and increased transplant waiting times. This retrospective study from a national transplant center at Helsinki University Hospital, Finland, aimed to assess the long-term outcomes of ABO-incompatible deceased donor pediatric liver transplants between 1987 and 2022. MATERIAL AND METHODS Sixteen (9.5%) of the 169 pediatric liver transplantations were ABO-ILTs. The median age at transplantation was 5.0 (0.5-15.4) years. Reasons for ABO-ILTs were acute liver failure (18.75%), malignancy (12.5%), small body size and long waiting time (25%), and other reasons (43.75%). The median post-transplant follow-up time was 147 (0.72-353) months. Patient and graft survival and occurrence of surgical complications were compared to ABO-identical transplants, and anti-ABO antibody titers were analyzed. RESULTS The 1-, 3-, and 5-year patient survivals were comparable between the ABO-I and ABO-compatible groups, being 81.3%, 73.9%, and 73.9% (ABO-I) and 87.5%, 82.5%, 77.9% (ABO-compatible), respectively. Three patients with ABO-ILTs died of sepsis and multiorgan failure during the first 3 months after transplantation. The occurrence of biliary complications and early vascular thrombosis (<30 days after transplantation) did not differ significantly between recipients with an ABO-ILT vs ABO-compatible liver graft. CONCLUSIONS The findings from this study support findings from previous studies that outcomes after ABO-incompatible liver transplants in children were comparable to outcomes from ABO-identical liver transplants.