Spanish Study Finds Kidney Transplants Without Blood Transfusions Feasible for Jehovah’s Witnesses

Surgeons at Hospital del Mar in Barcelona have shown that kidney transplants can be performed on Jehovah’s Witnesses without any blood transfusion, according to a retrospective propensity score-matched cohort study published in *Frontiers in Nephrology*. The study found that all 27 Witness recipients who had kidney transplants at the hospital between January 2016 and December 2025 completed the procedure without peri-transplant red blood cell transfusion. Nearly a third of the matched non-Witness controls required transfusion support.

Jehovah’s Witnesses decline allogeneic blood transfusions on religious grounds, which presents a particular challenge in kidney transplantation, where bleeding during and after surgery is a recognised complication. The source notes that perioperative red blood cell transfusion remains common in kidney transplantation, with reported rates around 30 percent, and that transfusion carries recognised risks, including HLA sensitisation and infection. The report states that about 127,000 Jehovah’s Witnesses live in Spain. It also notes that published literature on solid organ transplantation in Witness recipients has been dominated by case reports and small single-centre series.

The Barcelona team has used a transfusion-free protocol since 2016. Its core elements include raising pre-transplant haemoglobin to at least 13 grams per decilitre, usually with erythropoiesis-stimulating agents and often intravenous iron, and reviewing antiplatelet and anticoagulant medications. The protocol also uses antifibrinolytics such as tranexamic acid, limits blood sampling through the use of paediatric tubes, and includes a plan for rapid imaging and intervention if significant bleeding occurs. The authors documented individually for each patient whether they accepted blood products, fractions and procedures such as intraoperative cell salvage, noting that beliefs about blood components are not uniform among Witnesses.

The study compared all Witness recipients treated under the protocol with non-Witness controls drawn from the institutional transplant database, matching one-to-three on recipient age, sex, donor type and transplant date. Two planned transplants were postponed on the day of surgery because protocol criteria were not met: one patient’s haemoglobin was 12.5 grams per decilitre, and another was taking clopidogrel. Both later underwent transplantation once the criteria were satisfied and were included in the cohort. Patients were censored at last follow-up on 31 March 2026. The local ethics committee approved the study, and written informed consent was waived because of its retrospective, non-interventional design.

The primary outcome was transfusion avoidance, which the authors treated as an indicator of whether the protocol was feasible rather than as a comparative measure of clinical outcome. Peri-transplant transfusion was avoided in all 27 Witness recipients, while 24 of 74 controls, or 32.4 percent, received it. The authors emphasise that this result reflects the protocol’s implementation in practice and should not be read as a head-to-head comparison of surgical safety. The study reports that Witness recipients had higher haemoglobin at admission, 14.2 versus 11.5 grams per decilitre, and that ESA therapy and intravenous ferric carboxymaltose were used more often in the Witness group. Four of the 27 Witness recipients, 14.8 percent, had bleeding-related surgical complications, compared with eight of 74 controls, or 10.8 percent. The authors describe the difference in that estimate as imprecise. All four affected Witness patients developed severe postoperative anaemia, and two required surgical reintervention. The source adds that the four had a mean hospital stay of 30.3 days, compared with 10.9 days for the other 23 Witness recipients.

The authors acknowledge the limits of their evidence. They note that the retrospective, single-centre design restricts causal conclusions and generalisability, and that residual confounding cannot be excluded. All analyses were considered exploratory and descriptive, and non-significant findings were not interpreted as proof of equivalence or safety. The study also discusses ethics. The authors note that refusing transfusion is widely accepted as an expression of patient autonomy, but that in transplantation, where organs are scarce, it may create tension between autonomy and justice in allocation. They argue that excluding such patients without evidence of worse outcomes may raise equity concerns, and that declining transfusion should not be equated with non-adherence to medical care. The authors conclude that further multicentre studies with larger cohorts and longer follow-up are needed to define long-term outcomes, safety and optimal haemoglobin targets.

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