Evaluation of a prophylactic transfusion program on obstetric outcomes in pregnant women with sickle cell disease: A single centre retrospective cohort study

OBJECTIVE

To evaluate the effects of a prophylactic transfusion program (TP) on obstetric and perinatal outcomes in pregnant women with sickle cell disease (SCD).

METHODS

This retrospective cohort study included all singleton pregnancies among women with SCD in a French university tertiary care center between 1 January 2004 and 31 December 2017. The TP group included patients selected according to the French guidelines who received regular red blood cell transfusions during pregnancy until delivery. The factors associated with TP indication [year of birth, SCD genotype, history of acute chest syndrome and delayed hemolysis transfusion reaction (DHTR) risk score] were taken into account in a propensity score. A composite obstetric adverse outcome was defined associating birth before 34 gestational weeks and/or pre-eclampsia and/or small for gestational age and/or abruption and/or stillbirth and/or maternal death and/or neonatal death.

RESULTS

In total, 246 pregnancies in 173 patients were analyzed. Twenty-two pregnancies with a history of DHTR were excluded. A higher frequency of TP was found before 2013 [119/148 (80.4%) vs 38/76 (50%); p < 0.001]. Rates of preterm birth before 34 gestational weeks (5.6% vs 19.7%; p = 0.001), vaso-occlusive crisis (36.5% vs. 61.8%; p < 0.001), and acute chest syndrome (6.1% vs. 14.5%; p = 0.04) during pregnancy were decreased significantly in the TP group. Among the groups with and without composite obstetric adverse outcomes, the frequency of TP was 52.6% and 74.7%, respectively [odds ratio (OR) 0.30, 95% confidence interval (CI) 0.09-1.02]. The multivariate analysis shows that the TP was associated with a significant reduction in the risk of composite obstetric adverse outcomes (OR 0.28, 95% CI 0.08-0.97; p = 0.04).

CONCLUSION

A red blood cell TP may have an independent protective effect on maternal and perinatal adverse outcomes during pregnancy in women with SCD.

Les anémies aiguës et la stratégie transfusionnelle chez les drépanocytaires adultes

Worsening of anemia is very common in sickle cell disease. It is important to investigate specific complications related to sickle cell disease but also other causes of anemia in general. Transfusions or exchange transfusions are major therapeutic options and are frequently used for acute complications of sickle cell disease but also for primary and secondary prevention of some of the chronic complications. The transfusion strategy has been modified since the awareness of post-transfusion hemolysis by taking into account the transfusion risk score. A strong collaboration between the patient's expert center, the Blood center and the patient's hospitalization unit is required to make decisions. © 2023 Société nationale française de médecine interne (SNFMI). Published by Elsevier Masson SAS. All rights reserved.

Management of the blood supply for a Jk(a-b-) patient with an anti-Jk3 in preparation for an urgent heart transplant: An illustrative example of a successful international cooperation

The Kidd blood group system currently comprises two polymorphic and antithetical antigens, Jk^a and Jk^b, and one high-prevalence antigen, Jk3. Jk_null individuals do not express any of the Kidd antigens, and are at risk of developing an anti-Jk3 which is known to be dangerous and responsible for acute or delayed hemolytic transfusion reaction. We report a case of an immunized Jk_null patient, who was scheduled to undergo a heart transplant. In order to organize his blood provision management, two conference calls were held between the clinical team and the different staff involved in this challenging blood supply. In light of the blood needs, the available resources, and the constraints, a mix of fresh and frozen units were used. As the supply from France was not sufficient, Finland and New Zealand provided the majority of the fresh units. We report here how this international supply chain was organized, including the difficulties that we encountered. Anticipation, communication and flexibility were essential in making this heart transplant possible without needing to transfuse incompatible units.

Transcriptomic Signature of the CD24hi CD38hi Transitional B Cells Associated With an Immunoregulatory Phenotype in Renal Transplant Recipients

The role of B cells after transplant regarding allograft rejection or tolerance has become a topic of major interest. Recently, in renal transplant recipients, a B cell signature characterized by the overexpression of CD19⁺ CD38^hi CD24^hi transitional B cells has been observed in operationally tolerant patients and in belatacept-treated patients with significantly lower incidence of donor-specific antibodies. The phenotypic and functional characterization of these transitional B cells is far from exhaustive. We present the first transcriptomic and phenotypic analysis associated with this cell phenotype. Three populations were studied and compared: (i) transitional CD24^hi CD38^hi , (ii) CD24⁺ CD38^- , and (iii) CD24^int CD38^int B cells. Transcriptome bioinformatic analysis revealed a particular signature for the CD24^hi CD38^hi population. Phenotypic analysis showed that CD24^hi CD38^hi transitional B cells also expressed CD9, CD10, CD1b and inducible T cell costimulator ligand (ICOS-L) markers. In addition, we found enrichment of IL-10⁺ cells among CD24^hi CD38^hi cells expressing ICOS-L and CD1b, the latter showing regulatory properties. Renal transplant recipients treated with belatacept exhibited significant expression of CD1b. Our results show that transitional CD24^hi CD38^hi B cells exhibit a distinct and specific profile, and this could be helpful for understanding of immune-regulatory mechanisms and immune monitoring in the field of organ transplant and autoimmune disease.

Rare and transient anti-D antibody response in D(-) liver transplant recipients transfused with D(+) red blood cells

A retrospective analysis was conducted on 20 D(-) liver transplant (LT) recipients transfused with D(+) RBCs perioperatively and screened for RBC antibodies between 2 and 6 months later. None developed anti-D detectable by the indirect antiglobulin test. Two patients produced weak anti-D that reacted only with papain-treated RBCs at 10 and 11 days without any sign of immune haemolysis. Antibodies became quickly undetectable. These data suggest an unusual pattern of alloimmunization in LT recipients with rapid, weak and transient antibody response and support the safety of transfusing D(+) RBCs in most of D(-) patients during LT surgery.