Introduction: The clinical relevance of the intraoperative fresh frozen plasma (FFP)-to-red blood cell (RBC) transfusion ratio during adult liver transplantation (LT) is uncertain. We evaluated its association with postoperative pulmonary infection and 365-day mortality. Methods: We retrospectively analyzed adults undergoing first LT from January 2021 through December 2023 who received at least 1 U of intraoperative RBC. Patients were grouped by FFP:RBC ratio (≤1 vs. >1). Pulmonary infection was obtained from the pre-existing transplant registry; child-field -1 codes were decoded using the parent early-complication field, with manual reconciliation of the sole discordant record. Logistic regression was adjusted for MELD score and blood loss. Mortality was analyzed with Kaplan-Meier and Cox methods. Results: Among 149 patients, 84 had a ratio ≤1 and 65 had a ratio >1. The high-ratio group had lower preoperative fibrinogen and higher INR. Pulmonary infection occurred in 5/84 versus 11/65 patients (Fisher p=0.059; crude OR 3.22, 95% CI 1.06-9.79; p=0.039). The adjusted OR was 3.68 (95% CI 1.16-11.70; p=0.027). Twenty-one deaths occurred within 365 days; the adjusted HR was 1.38 (95% CI 0.57-3.35; p=0.478). Conclusion: A ratio >1 was associated with higher pulmonary-infection odds in crude and parsimonious adjusted logistic models, while the Fisher exact comparison was borderline. Sparse events, outcome-classification uncertainty, and confounding by indication preclude causal or safety conclusions. LT transfusion should remain individualized.
Background: The administration of RhD-positive red blood cell (RBC) units to RhD-negative patients may be unavoidable in emergency situations or blood shortage, posing a risk of anti-D alloimmunization. Data on the frequency and associated risk factors of such alloimmunization remain limited. Methods: We conducted a retrospective observational study at the University Hospital Basel, including all RhD-negative adults who received RhD-positive RBC transfusions between January 2011 and April 2024. Demographic, clinical, and transfusion data were retrieved from hospital records. Logistic regression was used to assess risk factors for post-transfusion alloimmunization. Results: Among 105 RhD-negative recipients (73% male, median age 68 years) the main transfusion indications were cardiovascular surgery and gastrointestinal bleeding. Post-transfusion antibody screening was performed in 49 (47%) patients; 19 (18% overall; 38% of those tested) developed alloantibodies, most commonly directed against Rh antigens, including 13 cases of anti-D alloantibodies. 34 patients (32%) were not tested due to early mortality. Alloimmunized patients received more RBCs (p = 0.048) and showed a trend toward higher FFP exposure (p = 0.063). In multivariable analysis, immunosuppressive therapy was significantly associated with lower odds of antibody development (OR 0.08, p = 0.037). Conclusions: Our findings confirm that anti-D alloimmunization after RhD-incompatible transfusion remains clinically relevant. The observed associations suggest that not only transfusions-specific factors, but also host-related factors as immune status influence alloimmunization risk. Systematic post-transfusion monitoring and further studies are warranted to optimize transfusion safety in RhD-negative patients.
Background: Pure red cell aplasia (PRCA) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an uncommon complication, most often associated with major or bidirectional ABO incompatibility. Daratumumab has emerged as a plasma cell–targeted therapy, but the supporting evidence remains limited. Methods: We systematically searched PubMed/MEDLINE, Scopus, and Web of Science from inception to 25 January 2026 for English-language reports of daratumumab-treated PRCA after allo-HSCT. Patient-level data were synthesized descriptively, and aggregate study-level reports were summarized separately. Results: Twenty patient-level reports comprising 53 patients were included, along with two aggregate study-level reports. The patient-level evidence consisted of 15 case reports, 2 case series, and 3 retrospective cohort studies. The median age was 52 years among 50 patients with available data, and 32 of 50 were male. Major ABO mismatch was present in 47 of 50 patients and bidirectional mismatch in 3. Daratumumab was used for refractory PRCA in 43 patients and as first-line therapy in 10. Prior PRCA-directed therapy was reported in 37 patients, most commonly rituximab. Daratumumab was administered intravenously in 29 of 52 patients and subcutaneously in 23 of 52. Hematologic response was achieved in 50 of 53 patients (94.3%), including complete response in 10, partial response in 1, and resolution without formal classification in 39 patients; 3 patients had no response. The median time to first response was 21 days, to best response 60 days, and to transfusion independence 29 days. No relapse was reported among 51 patients with available follow-up, although follow-up duration was variable. At last follow-up, 50 of 53 patients were alive. Infusion or injection reactions occurred in 11 patients and were predominantly mild to moderate. Infections were reported in 9 patients, hypogammaglobulinemia in 10 of 41 evaluable patients, and new or worsening graft-versus-host disease in 2 patients. Conclusion: Daratumumab was associated with high response rates and rapid erythroid recovery in PRCA following allo-HSCT, including in refractory and newly diagnosed cases. However, interpretation of safety and durability remains limited by heterogeneous reporting and variable follow-up.
Introduction: In Switzerland, platelet (PLT) donation is allowed with hemoglobin (Hb) ≥110 g/L and ≥120 g/L for women and men, respectively. We report on a policy of proposing PLT apheresis to female donors no longer eligible for whole blood (WB) donation because of low Hb and/or iron deficiency. Methods: We assessed 85 women with Hb <125 g/L and/or ferritin ≤ 15 µg/L who changed to PLT apheresis between 01/1997 and 12/2023 and underwent at least one PLT apheresis/year. Hb and ferritin were evaluated at the first WB donation, at the first and last PLT apheresis and were estimated as adjusted values over 30 PLT donations. Donor retention over a 24-month period was evaluated. Results: The switch to PLT apheresis occurred after a median of 3 (range: 1–33) WB donations. In 42 women (49%), both Hb and ferritin were low, 32 (38%) had low ferritin, and 11 (13%) low Hb only, respectively. Median age (range) at first WB donation and at last PLT donation was 30 years (18–53 years) and 45 years (19–68 years), respectively. Median (range) Hb and ferritin were 134 g/L (120–153 g/L) and 24 µg/L (2–177 µg/L) at the first WB donation and 130 g/L (103–154 g/L) and 14.5 µg/L (3–113 µg/L) at the last PLT apheresis. Over the course of 30 PLT donations and adjusted for donor age, an increasing trend was observed for both Hb (mean + 0.26 g/L; 95% CI: 0.16, 0.35; p < 0.001) and ferritin (mean + 0.48 µg/L; 95% CI: 0.21, 0.75; p < 0.001). At the end of a 24-month period, 94% (95% CI: 86.4%, 97.5%) women were still donating. Conclusion: Women with low Hb and/or iron deficiency benefit from a change to PLT donation and can be retained as regular, highly committed PLT donors.
Introduction: Microhaplotypes (MHs) are highly informative genetic markers suitable for forensic and clinical applications, including post-transplant monitoring in liquid biopsy. The aim of this study was to establish and evaluate a highly informative MH marker panel suitable for both chimerism analysis after allogeneic stem cell transplantation and for monitoring organ transplants using cell-free DNA (cfDNA). Two sequencing platforms (Illumina MiSeq and Oxford Nanopore Technologies [ONT]) were compared with regard to their suitability for reliable MH genotyping. Methods: Based on 98 candidates selected from the literature, a panel of 74 MH markers was developed and sequenced in 960 anonymized samples of healthy blood donors. Amplification was performed from genomic DNA in two multiplex PCRs generating short amplicons (95-150 bp). Library preparation and sequencing were carried out on the Illumina MiSeq platform (2 & times; 150 bp) and the ONT MinION (R10.4.1 flow cells). Bioinformatic analysis included quality filtering, read mapping (Bowtie2 and Minimap2), haplotype determination, and calculation of population genetic parameters such as polymorphism information content (PIC), power of discrimination (PD), expected heterozygosity (He), effective number of alleles (Ae), and Hardy-Weinberg equilibrium. Results: Evaluation of the sequencing results from 960 samples led to the exclusion of 20 MH markers due to low coverage or nonspecific amplifications. The remaining 54 MH loci were located on 22 chromosomes and comprised a total of 202 single nucleotide variations (SNVs). A balanced allele coverage ratio (>0.6) was observed for 43 loci. In total, 358 different alleles were identified, with most markers exhibiting between four and seven alleles. The PD exceeded 0.6 in 52 loci (mean 0.87), and most markers demonstrated high PIC and He values, indicating substantial genetic variability. Platform comparison revealed that ONT sequencing generated higher absolute read numbers, whereas Illumina sequencing achieved higher relative mapping efficiency and base accuracy. The proportion of uniquely mapped reads was comparable between the platforms. Additionally, previously undescribed SNVs were identified in 23 loci, potentially, further increasing haplotype diversity. Conclusion: The marker panel with 54 MHs demonstrated high genetic diversity and discriminatory power in the studied population. With the small amplicon size the MH marker panel could also be suitable for cfDNA. Further investigation with regard to the analysis of mixed DNA samples will support the usefulness of MHs as biomarkers for chimerism analysis in post-transplant monitoring.
