D-negative Patients Research Articles

Incidence of formation of anti-D between patients with and without a history of solid organ transplant.

Solid organ transplant surgeries including liver transplants constitute a substantial risk of bleeding complications and given frequent national blood shortages, supporting D-negative transplant recipients with D-negative red blood cell products perioperatively can be difficult for the transfusion services. This study was designed to compare the incidence of alloimmunization after D-mismatched red cell transfusions between patients with and without a history of solid organ transplant at a single tertiary care hospital. The patients undergoing solid organ transplants are on strong immunosuppressive regimens perioperatively to help reduce the risk of rejection. We hypothesized that the use of these immunosuppressive agents makes these patients very less likely to mount an immune response and form anti-D antibodies when exposed to the D-positive red blood cell products perioperatively. At our center, D-negative patients who received ≥1 unit of D-positive red blood cell products were identified using historical transfusion records. Antibody testing results were examined to determine the incidence of the formation of anti-D and any other red cell alloantibodies after transfusion and these results were compared between patients with and without a history of solid organ transplant. We were able to identify a total of 22 patients over 10 years with D-negative phenotype who had undergone a solid organ transplant and had received D-positive red blood cell products during the transplant surgeries. We also identified a second group of 54 patients with D-negative phenotype who had received D-positive red blood cell products for other indications including medical and surgical. A comparison of the data showed no new anti-D formation among patients with a history of D mismatched transfusion during solid organ transplant surgeries. Among our limited study population, we observed a very low likelihood of D alloimmunization among solid organ transplant recipients. A larger, prospective study could help further evaluate the need for prophylactic D matching for red cell transfusions during solid organ transplant surgeries.

Lack of alloimmunization to the D antigen in D‐negative orthotopic liver transplant recipients receiving D‐positive red blood cells perioperatively

D-negative patients undergoing orthotopic liver transplantation (OLT) might require a large number of red blood cell (RBC) units, which can impact the inventory of D-negative blood. The blood bank might need to supply these patients with D-positive RBCs because of inventory constraints. This study evaluates the prevalence of anti-D formation in D-negative OLT patients who received D-positive RBCs perioperatively, as this will assist in successful patient blood management. This was a retrospective study performed at a single academic medical centre. Electronic medical records for all 1052 consecutive patients who underwent OLT from January 2007 through December 2017 were reviewed. D-negative patients who were transfused perioperatively with D-positive RBCs and had antibody screening at least 30 days after transfusion were included. Of a total of 155 D-negative patients, 23 (14.8%) received D-positive RBCs perioperatively. Seventeen patients were included in the study. The median age was 54 years (range 36-67 years); 13 (76.5%) were male. The median number of D-positive RBC units transfused perioperatively was 7 (range 1-66 units). There was no evidence of D alloimmunization in any patient after a median serologic follow-up of 49.5months (range 31 days to 127.7months). The average number of antibody screening post OLT was 7.29. Our study showed that transfusion of D-positive RBCs in D-negative OLT recipients is a safe and acceptable practice in the setting of immunosuppression. This practice allows the conservation of D-negative RBC inventory.

Incidence of anti-D alloimmunization in D-negative individuals receiving D-positive red blood cell transfusion: A systematic review and meta-analysis.

The transfusion of D-negative red blood cells (RBCs) to D-negative patients has been widely adopted to prevent anti-D alloimmunization, especially in women of childbearing age. Still, transfusion of D-positive RBCs to D-negative recipients is occasionally inevitable in practice, and the resulting incidence of anti-D in different D-negative groups of patients has not been well summarized. We searched the relevant literature using PubMed, Cochrane Library, and Embase databases from inception date to 30 September 2021. We looked for studies of anti-D occurring in D-negative recipients who received D-positive RBC transfusions. The anti-D incidence was summarized with 95% confidence intervals (CIs). Data with similar characteristics were combined using a random-effects model. About 42 studies (2226 cases), which found anti-D, the exact volume of D-positive RBC transfused, and the follow-up time for anti-D detection, met the inclusion criteria. The pooled anti-D incidence was 64% (95% CI, range 55%-74%) in volunteers receiving small volumes of D-positive RBCs, 84% (95% CI, 74%-94%) in those receiving whole units, 26% (95% CI, 19%-32%) in mixed patients, 12% (95% CI, 8%-16%) in oncology patients, 27% (95% CI, 13%-40%) in trauma patients, 4% (95% CI, 0%-8%) in immune-compromised transplant patients, and 6% (95% CI, 1%-39%) in those with AIDS. Compared with the high frequency of anti-D in healthy D-negative volunteers given D-positive RBCs, we found a lower rate of anti-D immunization in various D-negative patients and almost none in transplant and AIDS patients.

Transfusion of D positive red cells to selected D-negative patients

BackgroundTo transfuse packed red blood cells isogroup ABO D is a usual transfusion practice. However, when there is not enough D-negative blood available, we can transfuse positive red blood cells to negative patients. Immunocompetent D-negative individuals may develop serologically detectable anti-D antibodies within 3 months after exposure to D-positive red blood cells. Material and methodOver the last 18 years, we have experienced situations of D-negative blood cell scarcity. In these situations, we have applied a clinical assistance protocol, selecting patients with lower risk of alloimmunization and chronic transfusion requirements. We have retrospectively evaluated this policy for the use of D-positive red blood cells in D-negative patients, focussing on alloimmunization and mortality. ResultsApplying the protocol, 3% of D-negative patients were transfused with D-positive units, with an alloimmunization rate of 12.3%. The rate of alloimmunization was higher in the younger age group and in those transfused with more units. No haemolytic reactions were reported. Mortality in the alloimmunized group was lower. ConclusionThe use of D-positive red blood cells in selected D-negative patients does not induce adverse reactions, is a safe practice and allows saving of a product that is sometimes limited.

Mitigation strategies for anti-D alloimmunization by platelet transfusion in haematopoietic stem cell transplant patients: a survey of NCCN® centres.

D-negative patients are at risk of developing an alloantibody to D (anti-D) if exposed to D during transfusion. The presence of anti-D can lead to haemolytic transfusion reactions and haemolytic disease of the newborn. Anti-D alloimmunization can also complicate allogeneic haematopoietic stem cell transplantation (HSCT) with haemolysis and increased transfusion requirements. The goal of this study was to determine whether cancer centres have transfusion practices intended to prevent anti-D alloimmunization with special attention in patients considered for HSCT. To understand transfusion practices regarding D-positive platelets in D-negative patients with large transfusion needs, we surveyed the 28 cancer centres that are members of the National Comprehensive Cancer Network® (NCCN® ). Nineteen centres responded (68%). Most centres (79%) avoid transfusing D-positive platelets to RhD-negative patients when possible. Four centres (21%) avoid D-positive platelets only in D-negative women of childbearing age. If a D-negative patient receives a D-positive platelet transfusion, 53% of centres would consider treating with Rh immune globulin (RhIg) to prevent alloimmunization in women of childbearing age. Only one centre also gives RhIg to all D-negative patients who are HSCT candidates including adult men and women of no childbearing age. There is wide variation in platelet transfusion practices for supporting D-negative patients. The majority of centres do not have D-positive platelet transfusion policies focused on preventing anti-D alloimmunization specifically in patients undergoing HSCT. Multicentre, longitudinal studies are needed to understand the clinical implications of anti-D alloimmunization in HSCT patients.

Serologic strategy in detecting RHD altered alleles in Brazilian blood donors

BackgroundWe evaluated different technological approaches and anti-D clones to propose the most appropriate serologic strategy in detecting the largest numbers of D variants in blood donors.MethodsWe selected 101 samples from Brazilian blood donors with different expressions of D in our donor routine. The tests were performed in immediate spin (IS) with eleven commercially available anti-D reagents in a tube and microplate. The D confirmatory tests for the presence of weak D included the indirect antiglobulin test (IAT) in a tube, gel and solid-phase red blood cell adherence (SPRCA). All DNA samples were extracted from peripheral blood and the D variants were classified using different molecular assays.ResultsThe RHD variants identified by molecular analysis included weak D types (1, 2, 3, 11 and 38) and partial Ds (DAR1.2, DAR1, DAR3.1, DAU0, DAU2, DAU4, DAU5, DAU6, DMH and DVII). The monoclonal-monoclonal blend RUM-1/MS26 was the best anti-D reagent used in detecting the D antigen in the IS phase in a tube, reacting with 83.2% of the D variants, while the anti-D blend D175 + 415 was the best monoclonal antibody (MoAb) used in a microplate to minimize the need for an IAT, reacting with 83.2% of the D variants. The D confirmatory tests using SPRCA showed a reactivity (3 - 4+) with 100% of the D variant samples tested.ConclusionOur results show that, even using sensitive methods and MoAbs to ensure the accurate assignment of the D antigen, at least 17% of our donor samples need a confirmatory D test in order to avoid alloimmunization in D-negative patients.

High frequency of variant RHD genotypes among donors and patients of mixed origin with serologic weak-D phenotype.

The current transfusion policy recommended for individuals with serologic weak-D phenotype is based on data derived from European-descent populations. Data referring to the distribution of RH alleles underlying weak-D phenotype among people of mixed origin are yet incomplete, and the applicability of European-based transfusion guidelines to this specific population is questionable. To evaluate the distribution of RHD variant genotype among individuals with serologic weak-D phenotype of both African and European descent. Donors and patients of mixed origin and with serologic weak-D phenotype were selected for the study. They were investigated using conventional RHD-PCR assays and RHD whole-coding region direct sequencing. One hundred and six donors and 58 patients were included. There were 47 donors and 29 patients with partial-D genotype (47/106, 44.3%, and 29/58, 50%, respectively). RHD*DAR and RHD*weak D type 38 represented the most common altered RHD alleles among donors (joint frequency of 39.6%), while weak D types 1-3 accounted for 10.4% of the total D variant samples. RHD*DAR was the most common allele identified in the patient group (frequency of 31%), and weak D types 1-3 represented 29.3% of the total. The frequency of partial D among mixed individuals with serologic weak-D phenotype is high. They should be managed as D-negative patients until molecular tests are complete.

It is worthwhile filling in the remaining blank spots for blood group antigen frequencies.

It is worthwhile filling in the remaining blank spots for blood group antigen frequencies.

Quantitation of fetomaternal haemorrhage and F cells in unusual maternal blood samples by flow cytometry using anti‐D and anti‐HbF

Fetomaternal haemorrhage (FMH) assessment by the Kleihauer-Betke test (KBT) is rapid but semi-quantitative and liable to false positive results. To compare FMH estimated by KBT with flow cytometry (FC) quantitation for 37 patients with massive FMH, obstetric risk factors or technical problems. Maternal blood was sent for analysis by FC after KBT. A variety of reagents including anti-haemoglobin F (HbF), anti-D and combined anti-HbF/anti-carbonic anhydrase (CA) were used. Eight cases of massive FMH (>100 mL fetal cells) causing fetal death or severe neonatal anaemia in late gestation were confirmed by FC. Anti-HbF FC identified maternal F cells and fetal cells. In some cases these red cell populations merged but they could be differentiated by anti-CA, labelling F cells only. Using KBT, false positive FMH results were obtained for 12 patients, who had strongly stained cells that were then shown by FC to be maternal F cells. All these patients had increased F cells (>5% of total red cells) whereas only 16% of patients with FMH and 22% of donors had elevated F cells. In contrast, anti-D FC was simple and rapid, quantitating D-positive FMH in all 15 D-negative patients except one with massive FMH of weak D fetal cells. Leucocytes in four samples bound anti-D, variably, giving erroneously high FMH, but they could be eliminated from FC analysis using combined anti-D/anti-CD45. FMH quantitation using anti-D by FC is suitable for the majority of maternal samples and could enable accurate targeted dosing of anti-D prophylaxis.

DEL RBC transfusion should be avoided in particular blood recipient in East Asia due to allosensitization and ineffectiveness

Previously, both primary and secondary anti-D alloimmunizations induced by "Asian type" DEL (RHD1227A allele) were observed in two incidents. We investigated how often these alloimmunization events occur. The transfusions of any D-negative patients were investigated in the First Affiliated Hospital of Xi'an Jiaotong University Medical College, China, during the entire 2009. The antigens of D, C, c, E, and e were routinely serotyped. The "Asian type" DEL variant was genotyped and the RHD heterozygote was determined through two published methods. The changes in anti-D levels were monitored by the indirect antiglobulin test (IAT) and flow cytometry. Thirty D-negative transfused patients were included in the study. We focused on 11 recipients who were transfused with packed red blood cells (RBCs) from DEL donors at least one time. Of those 11 recipients, seven were anti-D negative before transfusion and four were anti-D positive (one patient with an autoantibody). One of the seven pre-transfusion anti-D negative patients produced a primary-response anti-D after being transfused with 400 ml of DEL blood twice. All four pre-transfusion antibody positive patients were not observed hemoglobin (Hb) levels increased, as expected after transfusions. Two patients had an increase in anti-D from 1:8 to 1:64 by IAT, which was also shown by flow cytometry. None of the patients experienced an acute hemolytic episode. Our data indicated that the primary anti-D induced by DEL transfusion or the secondary anti-D elevated by DEL in a truly D-negative patient might not be unusual. We suggest that a truly D-negative childbearing-aged woman should avoid DEL transfusion to protect her from primary anti-D allosensitization. In addition, anti-D positive recipients should also avoid DEL red cell transfusion due to the delayed hemolytic transfusion reaction (DHTR).

Immunoprophylaxis using intravenous Rh immune globulin should be standard practice when selected D-negative patients are transfused with D-positive random donor platelets

Abstract A 67-year-old female developed excessive bleeding and thrombocytopenia following cardiovascular surgery. Her blood type was group A, D–. The only platelet products available in the transfusion service were random donor platelet concentrates from D+ donors. She was transfused with a pool of 6 D+ random donor platelet concentrates. Anti-D undetected in her pretransfusion serum by solid-phase antibody screen was present 11 days later. Retrospectively, the patient provided a history of having two pregnancies more than 40 years ago, prior to the availability of immunoprophylaxis by Rh immune globulin (RhIG). Although studies have shown that as many as 19 percent of D– people may develop anti-D following transfusion of platelets from D+ donors, there is no specific standard requiring immunoprophylaxis with RhIG to prevent Rh alloimmunization after transfusion of random donor platelet concentrates from D+ donors. In contrast, vigorous efforts are routine for preventing Rh alloimmunization in D– patients requiring red cell transfusions or D– females during pregnancy or after delivery of D+ newborns. The absence of a comparable practice standard for platelet transfusions is based, in part, on concern that intramuscular injections of conventional RhIG may cause local hemorrhage in thrombocytopenic persons. The recent availability of a Food and Drug Administration-approved preparation of intravenous RhIG makes Rh immunoprophylaxis in thrombocytopenic patients safe and practical. We recommend that intravenous RhIG be considered if it is necessary to transfuse random donor platelet concentrates from D+ donors to D– recipients. As a minimal standard, intravenous RhIG should be administered to all D– females of childbearing age who are recipients of pools of random donor platelet concentrates from D+ donors.

Red cell alloantibody development associated with heart and lung transplantation.

The development and persistence of clinically significant red cell alloantibodies were studied in 1132 patients who underwent a heart and/or lung transplant at Harefield Hospital. Clinically significant antibodies were detected in 15 patients (1.3%) preoperatively and appeared in a further 15 (2.1%) of 704 patients followed up 1-404 weeks after surgery. Anti-D developed in only 1 of 52 D-negative recipients of a D-positive donor graft and in only 2 of 6 D-negative patients who were transfused with between 6 and 32 units of D-positive red cells. Most antibodies that appeared after transplantation remained detectable for only a few weeks. Antibodies detected preoperatively that reacted only with papain-treated cells became persistently undetectable in 4 patients who were transfused with red cells expressing the corresponding antigen specificity. By contrast, antibodies detected preoperatively by indirect antiglobulin test were still detectable after periods of up to 260 weeks in 4 patients who received only antigen-negative red cells. Immunosuppressive therapy appeared to profoundly affect the natural history of red cell alloantibody production in these patients. The underlying mechanisms warrant further study.

Alloimmunization to RhD by Platelet Transfusions in Autologous Bone Marrow Transplant Recipients

Platelet transfusions from RhD-positive (D-positive) donors are often given to RhD-negative (D-negative) cancer patients. The low observed rate of alloimmunization has been attributed to disease and therapy-related immunosuppression. We have studied the occurrence of alloimmunization in 16 D-negative patients who did not have detectable anti-D prior to autologous bone marrow transplantation for malignant disease. All received D-positive platelets, but no other D-positive blood product. Three patients (19%) developed anti-D at 13, 24 and 83 days, respectively, after first receiving D-positive platelets, and after a total dose of 53, 65 and 119 D-positive platelet unit equivalents, respectively. Two of them also developed anti-C. The 13 patients in whom anti-D was not detected were also heavily transfused with D-positive platelets (mean +/- SD = 136 +/- 82 platelet unit equivalents). In 6 of them, the last recorded antibody screen was less than 3 months after the first D-positive platelets, and may not exclude a primary immune response. Thus, despite profound immunosuppression associated with autologous marrow transplantation, alloimmune responses to D-positive red cells in platelet concentrates can occur in some D-negative recipients.

Alloimmunization to D antigen and HLA in D-negative immunosuppressed oncology patients.

D-negative patients may be divided into responders and nonresponders when immunized with D-positive red cells (RBC). Forty-nine D-negative oncology patients who received D-positive RBCs via platelet and white cell transfusions were studied to determine if nonresponders to D were likely to form lymphocytotoxic antibody (LCA). Nine patients developed anti-D in 16 to 390 days (mean = 112) after 2.6 to 481 ml (mean = 106) of D-positive RBCs. Forty patients had no evidence of anti-D after 0.8 to 535 ml (mean = 98) of D-positive RBCs and were followed for 14 to 1275 days (mean = 192). The anti-D group had no prior D-positive RBC transfusions, and two of five women making anti-D had previous pregnancies but no record of anti-D. LCA was found in four of nine (44%) patients with anti-D and in 12 of 40 (30%) patients without anti-D (p less than 0.50). Since both D and antigens HLA are considered highly immunogenic, it is of interest that the ability to form anti-D or LCA does not correlate. In fact, more patients (16/49; 32%) made LCA than anti-D (9/49; 18%). Of the 21 alloimmunized patients, 4 made both antibodies, while 17 had selective alloimmunization. It would thus appear that alloimmunization to D and HLA are not strongly linked and may indeed be unrelated.

Clinical high-risk designation does not predict excess fetal-maternal hemorrhage

During a 5-year period, an enzyme-linked antiglobulin test was used to screen and quantitate fetal-maternal hemorrhage in 789 consecutive D-negative mothers who were delivered of D-positive babies. Six hundred seventy-two patients (85.2%) had no detectable fetal-maternal hemorrhage, and 117 patients (14.8%) had a detectable fetal-maternal hemorrhage. Eight of the 789 (1%) had a fetal-maternal hemorrhage >30 ml and required more than one vial of Rh immune globulin. Two patients with fetal-maternal hemorrhage of 29 and 30 ml also received additional Rh immune globulin. Each case was reviewed for the presence of high-risk features that are thought to predict patients at risk for fetal-maternal hemorrhage. Patients having a cesarean section or complicated vaginal delivery were considered to be in a group at high risk for fetal-maternal hemorrhage, while those with a spontaneous vaginal delivery were considered not to be at risk for fetal-maternal hemorrhage. Thirty-two of 237 patients (13.5%) in the risk group and 82 of 552 patients (15.3%) in the group not at risk had detectable fetal-maternal hemorrhage. The incidence of fetal-maternal hemorrhage for these two groups was not statistically different (p > 0.50 by χ2 analysis). If only patients in the risk group had been screened for fetal-maternal hemorrhage, then five of 10 (50%) who required more than one vial of Rh immune globulin would have been undertreated and at risk for developing anti-D antibodies. In addition, newborn birth weight, Apgar scores, and hematocrits were examined for 13 cases of fetal-maternal hemorrhage of ≥21 ml, and none of these characteristics could be used to predict patients at risk for fetal-maternal hemorrhage. Therefore, no maternal or newborn characteristics could be identified that would reliably predict patients at risk for fetal-maternal hemorrhage. We conclude that all D-negative patients with D-positive babies should continue to be screened for fetal-maternal hemorrhage to identify those patients requiring more than one vial of Rh immune globulin.

The UK National External Quality Assessment Scheme in Blood Group Serology. ABO and D grouping and antibody screening 1982-1983.

In seven surveys of blood grouping the overall rates of major error were 0.12% and 0.37% for uncomplicated ABO and D grouping respectively. Of 17 errors of ABO grouping, 13 were errors of transposition or interpretation and four were apparently technical. Of 52 errors of D grouping, 20 appeared to be errors of transposition or interpretation and 32 were apparently technical. Of the 32 technical errors of D grouping, 31 were D-negative grouped as Du (29) or D-positive (2) and most of these errors were due to misgrouping in the antiglobulin test. Causes of error in D grouping by antiglobulin test include anti-Bg and other contaminating immune antibodies, residual unabsorbed anti-A and the inherently high rate of false positive results obtained in the antiglobulin test. In view of the lack of benefit of Du testing to blood recipients or to pregnant women and of the possible adverse consequences of misgrouping D-negative patients as Du or D-positive, it is recommended that Du testing be abandoned in these groups of patients. The surveys of antibody screening demonstrated lack of standardisation and error rates similar to those previously reported in the UK for compatibility testing.