Routine Antibody Screening Research Articles

Heparin-Induced Thrombocytopenia: Is There a Role for Direct Thrombin Inhibitors in Therapy?

Heparin is widely used in the intensive care environment usually for thromboprophylaxis but also to facilitate extra-corporeal circuits such as renal replacement and ECMO. Heparin-induced thrombocytopenia (HIT) is a rare but extremely serious disorder. It is associated with significant morbidity and mortality. The diagnosis is often challenging particularly as thrombocytopenia can be caused by a number of other common conditions seen in intensive care. Unfortunately routine screening for HIT antibodies is not helpful as it is possible to have these but have no manifestation of the disease process. If the diagnosis of HIT is not considered and the patient does in fact have the disease process they are at risk of thrombotic episodes. This article reviews the pathophysiology of HIT and the challenges with making the diagnosis. We explore the role of newer anticoagulants that may have a role such as direct thrombin inhibitors.

Frequencies and specificities of "enzyme-only" detected erythrocyte alloantibodies in patients hospitalized in austria: is an enzyme test required for routine red blood cell antibody screening?

The aim of this study was to determine the frequencies and specificities of “enzyme-only” detected red blood cell (RBC) alloantibodies in the routine antibody screening and antibody identification in patients hospitalized in Austria. Routine blood samples of 2420 patients were investigated. The antibody screening was performed with a 3-cell panel in the low-ionic strength saline- (LISS-) indirect antiglobulin test (IAT) and with an enzyme-pretreated (papain) 3-cell panel fully automated on the ORTHO AutoVue Innova System. The antibody identification was carried out manually with an 11-cell panel in the LISS-IAT and with an enzyme-pretreated (papain) 11-cell panel. In total 4.05% (n = 98) of all patients (n = 2420) had a positive RBC antibody screening result. Of them 25.51% (25/98) showed “enzyme-only” detected specific or nonspecific RBC alloantibodies. Rhesus and Lewis system antibodies were found the only specificities of “enzyme-only” RBC alloantibodies: all in all 4.8% (4/98) were detected with anti-E, 3.06% (3/98) with anti-Lea, 3.06% (3/98) with anti-D after anti-D prophylaxis and 1.02% (1/98) with anti-e. In total, 14.29% (14/98) showed a nonspecific RBC alloantibody result with the enzyme test. The results of the present study demonstrate that a high number of unwanted positive reactions with the enzyme technique overshadows the detection of “enzyme-only” RBC alloantibodies. (Trial Registration: K-37-13).

BCSH guideline for the use of anti-D immunoglobulin for the prevention of haemolytic disease of the fetus and newborn.

BCSH guideline for the use of anti-D immunoglobulin for the prevention of haemolytic disease of the fetus and newborn.

Hemolytic disease of fetus and newborn due to maternal red blood cell alloantibodies in the Malay population.

Background:Maternal red blood cell (RBC) alloimmunization may lead to production of harmful antibodies that result in hemolytic disease of fetus and newborn (HDFN). There is insufficient data on the prevalence of HDFN due to RBC alloantibodies in the Malay neonatal population.Aim:The aim of this study was to determine the incidence of HDFN in the Malay neonatal population due to clinically significant RBC alloantibodies.Subjects and Methods:A cross sectional study was conducted in Transfusion Medicine Unit, Hospital Universitiy Sains Malaysia over one year period from January to December 2009. A total of 5163 Malay pregnant women who attended labor room for delivery were collected and analyzed prospectively. The blood samples were subjected to the standard immunohematological procedure for RBC antibody screening and identification using reagents of Diamed-ID Gel microtyping system. All the newborns with RBC alloantibody were investigated for the evidence of HDFN.Results:Thirty (0.58%) women were found to have clinically significant RBC alloantibodies. Most of the alloantibodies belonged to Rhesus (Rh) system (56.7%) where anti-E (33.3%) was the most common followed by anti-D (10.0%). Rh antibodies were the main cause of HDFN in fourteen (0.27%) neonates. Anti-D and anti-c were identified to cause moderate to very severe HDFN.Conclusions:With the low prevalence of clinically significant RBC alloantibodies and HDFN, routine antenatal antibody screening practice may not be advised as a routine practice at present, preferably reserved for those women of RhD negative or with history of HDFN, significantly of those attributed to anti-c.

Identification of a porcine pestivirus as a border disease virus from naturally infected pigs in Spain

Border disease virus (BDV), together with bovine viral diarrhoea virus 1 (BVDV-1), BVDV-2 and classical swine fever virus (CSFV), is classified in the genus Pestivirus within the family Flaviviridae ....

14-P

The trend to HLA antibody testing by multiplex immunoassays has led us to question the current role of the ELISA test in our HLA antibody screening. HLA antibody testing algorithms are used for efficiency and for standardization. The ELISA test has been part of the screening route. Routine HLA antibody screening is the first step of the algorithm. Initially, our lab used cytotoxicity and ELISA tests for HLA antibody screening. We currently screen renal candidates’sera by ELISA Class I alternating with the Luminex Class I/II screen methods. The conflicting results require follow-up tests. In the ASHI Proficiency survey, less than 10 labs are reporting results by the ELISA method, thus the results are not graded. The ELISA Class I Screen is cost effective for periodic PRA screening of our renal waitlist patients. We have observed results on some sera that tests positive on ELISA and then negative on a luminex screen. These patients(< 10% of all listed patients) exhibit high background on luminex platform. Conversely some patients’ sera test positive on the luminex screen and negative on the Elisa screen. The conflicting results could lead to confusing interpretation; however, in those patients with an established (3 to 6 succesive screens) negative, the change to positive or indeterminate has indicated a change in patient health or a sample discrepancy. A review of our results on ELISA screens over the past five years, (2007 through 2012) indeterminate or repeated tests were observed to be lot dependent, more than tech dependent. The current algorithm includes ELISA Class I screen, luminex screen (ClassI/II), and luminex single antigen tests. The elimination of this ELISA test is being considered as the more specific luminex screen result contributes information, including Class I and II antibody simultaneously. Although a reliable test methodology, the reduction in reagent cost, QC and proficiency on this less sensitive test would be a benefit of elimination.

Routine Screening for Rubella and CMV Antibodies During Pregnancy: Is it Justifiable?

Rubella and cytomegalovirus (CMV) screening during pregnancy is routinely carried out in India. However, its value has been questioned due to the absence of clearly effective intervention. This retrospective study evaluates the usefulness of rubella and CMV antibody screening during pregnancy. Serum samples received from pregnant women and children were tested for rubella- and CMV-specific IgM antibodies by capture ELISA. The data were analyzed to determine the incidence of rubella and CMV infection during pregnancy and in congenital infections. In asymptomatic pregnant females (n=505), rubella positivity was 3.16% and in women with bad obstetric history (BOH) (n=220), it was 7.72%, while CMV positivity was 5.9% in both asymptomatic pregnant women and in women with BOH. In children (n=200), the overall positivity for rubella- and CMV-specific IgM antibodies was 15 and 25%, respectively. A declining trend was observed in the incidence of both rubella and CMV infections in pregnant women and in women with BOH. In children, the incidence of congenital rubella syndrome has declined, but the incidence of CMV infection has remained almost the same in 5years. The incidence of rubella has reduced over the past 5years and can further be prevented by providing direct protection to women and school girls with rubella vaccines. Primary CMV infection in pregnancy is the main problem, and due to the unavailability of efficient and safe treatment, routine antenatal screening for rubella and CMV should be reserved for women with obstetric complications only.

Hepatitis C Virus Screening and Management of Seroconversions in Hemodialysis Facilities

Over the past two decades, healthcare-associated exposure has increasingly been proved to be a means of hepatitis C virus (HCV) transmission, especially in hemodialysis facilities. The prevalence of HCV among hemodialysis patients is known to be several times greater than that of the general population of the United States, and chronic HCV infection is associated with significant morbidity and mortality among these patients. During 2008-2011, HCV infection outbreaks were identified in multiple US hemodialysis facilities, resulting in at least 46 new HCV infections among hemodialysis patients. These outbreaks, linked to infection control breaches, also highlight the failure of some facilities to follow established guidelines for routine HCV antibody (anti-HCV) screening and response to new HCV infection among hemodialysis patients. Current national guidelines recommend screening of hemodialysis patients for anti-HCV on facility admission and, for susceptible patients, on a semiannual basis. Here, we seek to underscore the importance of compliance with national recommendations for anti-HCV screening of hemodialysis patients and actions to be taken in the event of possible HCV transmission within a hemodialysis facility. These include general steps to ensure that: hemodialysis patients are routinely screened for anti-HCV to facilitate early detection of new infections; newly infected patients are informed of the change in their HCV status and undergo clinical evaluation; and public health officials are notified of new HCV infections in a timely manner. We then focus on the need to assess infection control practices at the facility, with particular attention given to safe handling of injectable medications, hand hygiene and disinfection practices. In the absence of a vaccine, routine screening and adherence to standard infection control practices will remain the key strategies for preventing HCV transmission in hemodialysis units.

Automation Highlights from the Literature

Automation Highlights from the Literature

The "silent" global burden of congenital cytomegalovirus.

Human cytomegalovirus (CMV) is a leading cause of congenital infections worldwide. In the developed world, following the virtual elimination of circulating rubella, it is the commonest nongenetic cause of childhood hearing loss and an important cause of neurodevelopmental delay. The seroprevalence of CMV in adults and the incidence of congenital CMV infection are highest in developing countries (1 to 5% of births) and are most likely driven by nonprimary maternal infections. However, reliable estimates of prevalence and outcome from developing countries are not available. This is largely due to the dogma that maternal preexisting seroimmunity virtually eliminates the risk for sequelae. However, recent data demonstrating similar rates of sequelae, especially hearing loss, following primary and nonprimary maternal infection have underscored the importance of congenital CMV infection in resource-poor settings. Although a significant proportion of congenital CMV infections are attributable to maternal primary infection in well-resourced settings, the absence of specific interventions for seronegative mothers and uncertainty about fetal prognosis have discouraged routine maternal antibody screening. Despite these challenges, encouraging results from prototype vaccines have been reported, and the first randomized phase III trials of prenatal interventions and prolonged postnatal antiviral therapy are under way. Successful implementation of strategies to prevent or reduce the burden of congenital CMV infection will require heightened global awareness among clinicians and the general population. In this review, we highlight the global epidemiology of congenital CMV and the implications of growing knowledge in areas of prevention, diagnosis, prognosis, and management for both low (50 to 70%)- and high (>70%)-seroprevalence settings.

Prevalence of Diego blood group antigen and the antibody in three ethnic population groups in Klang valley of Malaysia

Background:Diego blood group antigen, Di(a), is very rare among Caucasians and Blacks, but relatively common among the South American Indians and Asians of Mongolian origin. The antibody to Di(a) is clinically significant to cause hemolytic disease in a new-born or hemolytic transfusion reaction.Objectives:This study was designed to determine the prevalence of Di(a) antigen among the blood donors from the three major ethnic groups in Klang Valley of Malaysia as well as to find an incidence of an antibody of the Diego antigen, anti-Di(a), in a tertiary care hospital to ascertain the need to include Di(a+) red cells for an antibody screen cell panel.Materials and Methods:Serological tests were performed by column agglutination technique using commercial reagents and following instruction as per kit insert.Results:Di(a) antigen was found with a frequency of 2.1% among the Malaysians donors in three ethnic groups viz, Malay, Chinese and Indian. It was present among 1.25% of 401 Malay, 4.01% of Chinese and 0.88% of 114 Indian origin donors. None of the 1442 patients, including 703 antenatal outpatients, had anti-Di(a) in serum.Conclusion:The prevalence of Di(a) antigen was found among the donors of all the three ethnic background with varying frequency. Inclusion of Di(a+) red cells in routine antibody screening program would certainly help in detection of this clinically significant antibody and to provide safe blood transfusion in the Klang Valley, though the incidence of antibody appears to be very low in the region.

Efficiency of RBC Antibody Detection Methods: Comparison of Manual Indirect Antiglobulin Test (IAT) to a Method Using Very Low Ionic Strength Conditions (vLIS/IAT).

Abstract 2276Is has long been known that RBC antibody detection is enhanced following a decrease in the ionic concentration. In the past we added into our routine pre-transfusion antibody screen a new test, which employs ionic strength conditions between 15 to 17% of the ionic strength of 0.9% NaCl (vLIS/IAT): 2 drops of patient's plasma and one drop of 3% RBC are incubated for 15 minutes in 0.5 mL of 5% mannitol, pH 6.0 with phosphate buffer, containing 8mM EDTA. The RBCs are washed with normal saline and tested for agglutination by an anti-IgG reagent. Other published low ionic strength methods decrease the ionic concentration less, up to about 50%.In the process of pre-transfusion testing we found 711 patients with one, two or more blood group antibodies. The following table shows the specificities and quantities of clinically significant antibodies detected by these two methods. The following antibody specificities were not included: those that were present only in small quantities, directly agglutinating IgM antibodies and anti-Lea and Lebantibodies which are usually considered to be clinically insignificant.Antibody specificityTotal Number detected% Detected by IAT% Detected by vLIS/IATC7171.8%93.0%c3680.5%92.0%D14768.7%97.3%E22040.3%95.5%Fya4470.5%95.5%Jka6060.0%96.7%K15489.0%76.0%M2334.8%87.0%S1850.0%100%Total773Avg. 62.8%Avg. 92.6%Overall, vLIS/IAT detected an increase in clinically relevant antibodies compared to IAT. This is clearly seen in the case of anti-E, anti-D, anti-Jka, anti-M and anti-S antibodies. Anti-K antibodies, however, were detected preferably by IAT. It should be noted that more anti-Le antibodies, although not shown here, were detected either by IAT or by direct agglutination (IgM antibodies).In summary, these data show that vLIS/IAT improved antibody detection when incorporated into routine pre-transfusion tests. They also indicate that one method does not detect all clinically significant antibodies; therefore it is beneficial to use two methods which in combination cover the varying spectra of RBC antibodies. Disclosures:No relevant conflicts of interest to declare.

High throughput automated chromatin immunoprecipitation as a platform for drug screening and antibody validation

Chromatin immunoprecipitation (ChIP) is an assay for interrogating protein-DNA interactions that is increasingly being used for drug target discovery and screening applications. Currently the complexity of the protocol and the amount of hands-on time required for this assay limits its use to low throughput applications; furthermore, variability in antibody quality poses an additional obstacle in scaling up ChIP for large scale screening purposes. To address these challenges, we report HTChIP, an automated microfluidic-based platform for performing high-throughput ChIP screening measurements of 16 different targets simultaneously, with potential for further scale-up. From chromatin to analyzable PCR results only takes one day using HTChIP, as compared to several days up to one week for conventional protocols. HTChIP can also be used to test multiple antibodies and select the best performer for downstream ChIP applications, saving time and reagent costs of unsuccessful ChIP assays as a result of poor antibody quality. We performed a series of characterization assays to demonstrate that HTChIP can rapidly and accurately evaluate the epigenetic states of a cell, and that it is sensitive enough to detect the changes in the epigenetic state induced by a cytokine stimulant over a fine temporal resolution. With these results, we believe that HTChIP can introduce large improvements in routine ChIP, antibody screening, and drug screening efficiency, and further facilitate the use of ChIP as a valuable tool for research and discovery.

Constructing a Population-Based Research Database from Routine Maternal Screening Records: A Resource for Studying Alloimmunization in Pregnant Women

BackgroundAlthough screening for maternal red blood cell antibodies during pregnancy is a standard procedure, the prevalence and clinical consequences of non-anti-D immunization are poorly understood. The objective was to create a national database of maternal antibody screening results that can be linked with population health registers to create a research resource for investigating these issues.Study Design and MethodsEach birth in the Swedish Medical Birth Register was uniquely identified and linked to the text stored in routine maternal antibody screening records in the time window from 9 months prior to 2 weeks after the delivery date. These text records were subjected to a computerized search for specific antibodies using regular expressions. To illustrate the research potential of the resulting database, selected antibody prevalence rates are presented as tables and figures, and the complete data (from more than 60 specific antibodies) presented as online moving graphical displays.ResultsMore than one million (1,191,761) births with valid screening information from 1982–2002 constitute the study population. Computerized coverage of screening increased steadily over time and varied by region as electronic records were adopted. To ensure data quality, we restricted analysis to birth records in areas and years with a sustained coverage of at least 80%, representing 920,903 births from 572,626 mothers in 17 of the 24 counties in Sweden. During the study period, non-anti-D and anti-D antibodies occurred in 76.8/10,000 and 14.1/10,000 pregnancies respectively, with marked differences between specific antibodies over time.ConclusionThis work demonstrates the feasibility of creating a nationally representative research database from the routine maternal antibody screening records from an extended calendar period. By linkage with population registers of maternal and child health, such data are a valuable resource for addressing important clinical questions, such as the etiological significance of non-anti-D antibodies.

Coeliac Disease in Subfertile Couples in the Netherlands

Background: Subfertility has been assumed as a long-term complication of unrecognized and/or untreated coeliac disease (CD). No data exist on the association between subfertility and CD in The Netherlands. Aims: To determine; 1.) the prevalence of (un)recognized CD in subfertile male-female couples in the Netherlands; 2.) if routine antibody screening for CD should be performed in patients visiting a fertility clinic. Methods: Subjects included 1038 male-female couples (n=2076) who visited the fertility clinic of the Leiden University Medical Centre in the Netherlands, between 2003-2009. All patients were serological screened, and unrecognized CD was defined in cases with simultaneous positive test results for antibodies against anti-tissue transglutaminase and endomysium. Clinical data was collected; gender, age, height, weight and diagnosis of subfertility. All patients were anonymized. The prevalence of unrecognised CD was compared to the one in the general adult population in the Netherlands (0.35%) (1) Results: The prevalence of unrecognized CD in subfertile male-female couples was 0.48% (10/2076), 0.3% female and 0.4% male (p=NS). In 1.5% of the women with an ovulation disorder CD was diagnosed (p=0.04). Compared to the control group, similar CD prevalences were found within the other subfertility categories unexplained subfertility, tuba pathology and androgenic disorder (p=NS). Conclusion: In our well-powered study cohort of subfertile male-female couples, the prevalence of unrecognized CD is comparable to the general population in the Netherlands. Unrecognized CD was 5 times more often detected in women with ovulation disorder compared to the control group, which suggest a possible association between CD and subfertility in females. No association was found in subfertile men and couples with unexplained subfertility. We would suggest performing serological screening for CD in females who are visiting the fertility clinic in the Netherlands.

Hemolytic disease of the fetus and newborn caused by an antibody to a low‐prevalence antigen, anti‐SARA

The first case describing the SARAH (SARA) antigen occurred in 1990, in an Australian blood donor. Hemolytic disease of the fetus and newborn (HDFN) due to anti-SARA has not been previously described. We report a case of HDFN in a multiparous female. The pregnancy was unremarkable except that she was involved in a seemingly minor motor vehicle accident at 25 weeks' gestation. Routine prenatal antibody screening was negative throughout the pregnancy. She presented at 37 weeks' gestation because of decreased fetal movements. Labor was induced and a 2702-g infant male was delivered. The infant's hemoglobin was 49 g/L and the bilirubin was 153 µmol/L. Blood samples from the parents and infant were referred to Canadian Blood Services National Immunohematology Reference Laboratory and subsequently to the Australian Red Cross Red Cell Reference Service. The father's and infant's red blood cells were confirmed to be SARA positive, and the mother's plasma contained anti-SARA. The infant was successfully treated with a double-volume exchange transfusion. This is the first example of HDFN associated with this antibody.

Parvovirus B19 antibodies and correlates of infection in pregnant women attending an antenatal clinic in central Nigeria

Human parvovirus B19 infection is associated with spontaneous abortion, hydrops foetalis, intrauterine foetal death, erythema infectiosum (5th disease), aplastic crisis and acute symmetric polyarthropathy. However, data concerning Nigerian patients with B19 infection have not been published yet. The purpose of this study was to establish the prevalence of B19 IgG and IgM antibodies, including correlates of infection, among pregnant women attending an antenatal clinic in Nigeria. Subsequent to clearance from an ethical committee, blood samples were collected between August-November 2008 from 273 pregnant women between the ages of 15-40 years who have given their informed consent and completed self-administered questionnaires. Recombinant IgG and IgM enzyme linked immunosorbent assay kits (Demeditec Diagnostics, Germany) were used for the assays. Out of the 273 participants, 111 (40.7%) had either IgG or IgM antibodies. Out of these, 75 (27.5%) had IgG antibodies whereas 36 (13.2%) had IgM antibodies, and those aged 36-40 years had the highest prevalence of IgG antibodies. Significant determinants of infection (p < 0.05) included the receipt of a blood transfusion, occupation and the presence of a large number of children in the household. Our findings have important implications for transfusion and foeto-maternal health policy in Nigeria. Routine screening for B19 IgM antibodies and accompanying clinical management of positive cases should be made mandatory for all Nigerian blood donors and women of childbearing age.

Seropositivity of Chlamydophila pneumoniae immunoglobulin G antibody of HIV/AIDS patients in Abuja, Nigeria

Objective To detect IgG antibody to Chlamydophila pneumoniae (CP) in sera of HIV/AIDS patients and provide rationale for inclusion of routine screening for anti-CP antibodies and anti-chlamydial agents in the Nigerian National HIV/AIDS Management Plan. Methods Serum samples from 34 consenting HIV/AIDS patients attended a Government-approved Antiretroviral Treatment Facility in Abuja were screened by enzyme-linked immunosorbent assay for anti-CP IgG antibody using ImmunoComb® Chlamydia Bivalent IgG Test kit (Orgenics, Israel). Results Anti-CP IgG antibody was detected in 20 (58.8%) of 34 patients tested. The detection rate was higher among the males (8/13; 61.5%) than the females (12/21; 57.1%). Patients of the age group 16-30 years had the highest (7/10; 70%) detection of anti-CP IgG antibody. Conclusions The result of the present study suggests the presence of anti-CP antibodies in sera of the HIV/AIDS patients, and reinforces the need for routine screening for anti-CP antibodies as a necessary intervention to reduce the burden of Chlamydophila pneumoniae (C. pneumoniae) infections and to reduce HIV-positive morbidity in Nigeria. The outcome of this study also provides justification for the possible inclusion of anti-chlamydial agents in the National HIV/AIDS Management Plan to provide prophylaxis against or treat active C. pneumoniae infections.

Pregnancy Outcomes in Women With Thyroid Peroxidase Antibodies

To estimate the prevalence of antithyroid peroxidase antibodies in the general obstetric population and to compare pregnancy outcomes in women who are antithyroid peroxidase-antibody positive with those who are antithyroid peroxidase-antibody negative. Between November 2000 and April 2003, all women who presented for prenatal care underwent thyroid screening. Serum samples from women without clinical hypothyroidism who had been screened in the first 20 weeks of gestation and delivered a singleton newborn weighing 500 g or more were analyzed for concentrations of antithyroid peroxidase antibodies. Serum thyroid peroxidase antibody levels were determined using a chemiluminescent immunoassay. Pregnancy outcomes in women with positive antithyroid peroxidase antibodies (more than 50 international units/mL) were compared with those with negative levels. Serum samples from 17,298 women were tested. Of these, 1,012 (6%) women were identified with positive antithyroid peroxidase antibodies. Women who were antithyroid peroxidase-antibody positive were older, heavier, and more often parous than women with negative antithyroid peroxidase antibodies. Rate of placental abruption was threefold higher in women with antithyroid peroxidase antibodies (1.0% compared with 0.3%, odds ratio 3.4, 95% confidence interval 1.7-6.7) after adjustment for differences in maternal demographics. Seven of the 10 abruptions associated with antithyroid peroxidase antibody occurred in women with normal thyroid-stimulating hormone and free thyroxine levels. Antithyroid peroxidase antibodies are present in 6% of the general obstetric population and are associated with a threefold increase in the rate of placental abruption. However, this increase in placental abruption does not currently warrant routine antithyroid antibody screening during pregnancy. II.

Red-blood-cell alloimmunization and female sex predict the presence of HLA antibodies in patients undergoing liver transplant

Refractoriness to platelet transfusion because of HLA antibodies can jeopardize the outcome of patients who require platelet support during surgery. As routine screening for HLA antibodies would pose a huge burden on presurgical work-ups, a stratification of patients according to the risk of having HLA antibodies is warranted. Clinical and laboratory data from 1351 patients submitted to liver transplant were analyzed to determine the accuracy of RBC alloimmunization and other patient features to predict the concomitant presence of HLA antibodies. Predictive variables were selected through binary logistic regression and their accuracy to prognosticate HLA alloimmunization was calculated by contingent table methods. RBC and HLA antibodies were detected in 70 (5·2%) and 71 (5·3%) patients, respectively. Female sex and RBC alloimmunization were the only patient features associated with HLA aloimmunization. Risk of being HLA immunized increased from male patients without RBC antibodies (n = 842; 1·5% with HLA antibodies) to female patients with RBC alloimmunization (n = 36, 36·2% with HLA antibodies), being of 9·7% in the remaining 473 patients. In women, the positive and negative predictive values of RBC alloimmunization to prognosticate HLA alloimmunization were 36% and 90%, respectively. In male patients, such values were 12% and 99%, respectively. The incidence of HLA immunization decreased after the introduction of universal leukoreduction in 2002. RBC alloimmunized female patients that may require platelet support during liver transplant should be preoperatively evaluated for HLA antibodies. Such evaluation is unnecessary in male patients without detectable RBC antibodies. Decision-making in the remaining patients must be individualized.