Screening of blood donors for erythrocyte alloantibodies

Abstract

Objective

To assess the prevalence of the anti-red blood cell antibodies in the donor population of Delhi.

Methods

This prospective study was conducted in Regional Blood Transfusion Centre (RBTC), Lady Hardinge Medical College (LHMC) and associated hospitals from March 2010 to March 2011. Antibody screening of all donor serum/plasma was performed as routine immunohaematological procedure. Any positive sera were further investigated to identify the specificity of irregular erythrocyte antibody by commercially available red cell panel (ID-Dia Panel, Diamed-ID Microtyping System). The titres and thermal amplitude of the identified antibodies were evaluated.

Results

A total of 7756 donors were screened, of which 7648 donors were males (98.6%) and 108 were females (1.4%). The maximum number of donors belonged to age group of 26–30 years. A total of four donors showed presence of alloantibodies in their serum (0.05%). On antibody identification, two of them were anti-C, one was anti-Lewis^a antibody and one was autoantibody.

Discussion

This study was conducted to highlight the significance of detecting irregular erythrocyte antibodies in healthy donors.     

Screening for haemochromatosis: prevalence among Danish blood donors

Hereditary haemochromatosis is an autosomal recessive disease that is genetically expressed by excessive accumulation of iron in the tissues, resulting in cirrhosis, diabetes mellitus, cardiomyopathy and hypogonadism. As the disease may be diagnosed before the appearance of symptoms, and prevented by repeated phlebotomies, there are strong implications for adoption of a screening procedure. Determinations of transferrin saturation (TS) and serum ferritin concentration (SF) were used to screen 4302 blood donors, who were selected for follow-up studies if they fulfilled any of the following three criteria: (i) TS greater than or equal to 0.7; (ii) TS greater than or equal to 0.5 together with SF greater than or equal to 150 micrograms l-1; (iii) SF greater than or equal to 300 micrograms l-1. A total of 58 subjects who fulfilled at least one of these criteria were reinvestigated, after which 18 individuals still fulfilled at least one criterion. Fifteen subjects having SF greater than or equal to 300 micrograms l-1 were offered liver biopsy and thirteen of these accepted. In one individual, no stainable iron was detected, and two subjects did not fulfil the previously established diagnostic criteria for the diagnosis of hereditary haemochromatosis. Ten subjects who had a high TS and liver iron grade 2-4 according to Bassett were classified accordingly as homozygotes. On the basis of these results, the prevalence of haemochromatosis in Denmark was estimated to be 0.0037-0.0046.     

Specificities of leucocyte alloantibodies in transfusion-related acute lung injury and results of leucocyte antibody screening of blood donors

Background Antibody-mediated transfusion-related acute lung injury (TRALI) is an important cause of transfusion-associated morbidity and death. Preventive strategies are currently a matter of debate. Methods Specificities of leucocyte antibodies implicated in previous severe TRALI reactions were determined using standard techniques. Based on these results, a leucocyte antibody screening strategy for the testing of parous female donors was introduced. Results Of 36 TRALI cases, 17, 12, four and three were due to human leucocyte antigen (HLA) class II, human neutrophil alloantigen (HNA), HLA class I, and mixtures of HLA class I and II antibodies, respectively. HNA-3a antibodies accounted for 10 of 12 HNA antibody-mediated reactions and 6 of 10 fatalities including one after transfusion of red blood cells. Investigation 5332 parous female donors showed leucocyte antibodies in 473 samples, resulting in an alloimmunization rate of 8·9%. Sixty-one per cent of these donors presented HLA class I, 19% class II, 12% HLA class I and II antibodies and 5% HNA antibodies. Additional HLA class I antibodies were found in 39% of HLA class II and in 17% of HNA antibodies containing sera. Our restrictive plasma strategy did not result in a shortage of plasma or platelets. No antibody-mediated TRALI case was observed since introduction of the policy of plasma from male, nulliparous or tested multiparous donors. Conclusion Compared to HLA class I antibodies, those directed against HLA class II and HNA-3a were of greater clinical relevance. Isolated HLA class I antibody screening was found to be insufficient for leucocyte antibody screening.     

Screening for viral markers in volunteer and replacement blood donors in West Africa

BACKGROUND AND OBJECTIVES: West Africa is a highly endemic area for viral infections. The prevalence of five viral markers was determined in Ghanaian blood donors. MATERIALS AND METHODS: Replacement and volunteer blood donors were screened using enzyme immunoassays (EIAs) for hepatitis B surface antigen (HBsAg), human immunodeficiency virus antibodies (anti-HIV), HIV p24 antigen, human T-cell lymphocytotrophic virus-I and -II antibodies (anti-HTLV-I/II) and hepatitis C virus antibodies (anti-HCV). RESULTS: HBsAg was present at an equally high frequency (15%) in young volunteer (median age 18 years) and older replacement (median age 33 years) blood donors. In contrast, the prevalence of anti-HIV and anti-HCV was significantly higher in replacement blood donors (2.4 and 0.3%, respectively, P < 0.001). HCV RNA was detected in 74 or 55% of seropositive donors, depending on the confirmatory criteria used. No p24 antigen-positive/anti-HIV-negative donations were found. The prevalence of HTLV-I/II was generally low (0.5%). CONCLUSION: All blood donations should be screened for hepatitis B virus (HBV), HIV and HCV markers.     

Screening tests for blood donors presumed to have transmitted the acquired immunodeficiency syndrome

We investigated 18 sets of blood donors from 12 to 50 months after they donated blood to recipients who subsequently developed the acquired immunodeficiency syndrome (AIDS). Within each donor set, only one donor was suspected of having transmitted the disease (ie, member of an AIDS risk group). The other donors (n = 189) were not risk group members and served as controls. A number of laboratory tests distinguished suspected from nonsuspected donors, including determination of T helper/T suppressor cell ratio, antibody to hepatitis B core antigen, and immune complexes, but none of these was as sensitive and specific as tests for antibody to the human retrovirus, HTLV-III/LAV.     

Screening blood donors for hereditary hemochromatosis: decision analysis model comparing genotyping to phenotyping

OBJECTIVE: The identification of a gene for hereditary hemochromatosis in 69-100% of typical hemochromatosis patients has resulted in a genotypic test to identify persons with the typical missense mutation. Population screening by genotyping has the potential to reduce screening costs because of a high specificity of the genetic test. METHODS: Decision analysis techniques are used to compare the outcome, utility, and incremental cost savings of a plan to screen voluntary blood donors and their siblings for hemochromatosis using a genotypic test (C282Y mutation) with phenotypic tests (transferrin saturation, serum ferritin). RESULTS: Genotypic screening is less expensive than phenotypic screening only if the cost of the initial genetic test is less than $20. The screening program saves money (dominant strategy) if the cost of the initial genetic test is less than $28. Incremental cost saving declines as the cost of the gene test increases. At a gene test cost of $173, it costs $109,358 to identify a homozygote with potential life-threatening illness. Incremental cost saving also declines as the penetrance of the hemochromatosis gene in the population screened decreases. Phenotypic screening with confirmatory genetic testing results in a cost of $2,711 per homozygote with life-threatening complications. CONCLUSIONS: Population screening programs for hemochromatosis have the potential to save money. Optimal strategies for screening include initial testing for iron overload (phenotyping) with confirmatory genetic testing, or initial genetic testing if the test is less than $28.     

Hepatologic dispensaire for blood donors

By means of hepatological examinations of 119 blood donors who became conspicuous by liver screenings in 57 cases we could prove an adipose degeneration without, in 16 cases a fatty degeneration of the liver without, in 9 cases an adipose degeneration with and in 15 cases a fatty degeneration of the liver with mesenchymal reaction. Only 9 blood donors had normal liver findings. 90% of the punctured blood donors had an overweight up to a maximum of 35 kg in comparison to the ideal weight. 30% of the punctured patients admitted a clearly increased daily consumption of alcoholic beverages. By means of repeated punctures on 24 blood donors after 8 to 32 months after an adequate consultation in three cases a normalisation and in eight cases an improvement of the liver findings could be proved. In 13 cases the findings remained unchanged, also the anamnestic and clinical findings corresponded to this. In 2 blood donors by means of a threefold liver puncture in the observation period of 48 months also a clear retrogression of the liver findings was proved. With this was also connected the reduction of overweight and the avoiding of alcohol. Thus our investigations confirmed that overweight and abuse of alcohol are essential factors for the development of a fatty degeneration of the liver. Of an infectious hepatitis reported in the anamnesis in 10 blood donors histologically in no case residues were established. Thus the liver dispensary is of great importance for the care of blood donors who become conspicuous by screening tests. On the one hand the importance is referred to the blood donor himself, on the other hand to the group of donors. Blood donors taken out of the group could again be included in the special group, when after the exclusion of known noxae the retrogression of unspecific liver changes took place.     

A study-screening of blood donors for blood transmissible diseases

Aims

Blood donors are of voluntary and replacement type. All donors, especially voluntary, are considered as slow risk for seropositive status for Hepatitis B and C, HIV and syphilis. The present study endeavors to screen blood donors-a slow risk group and evaluate the resultant data.

Methodology

We screened 23,068 donors serologically over 2 years for the above blood transmissible diseases. Serum alanine aminotranferase (ALT) and bilirubin were evaluated as surrogate markers in hepatitis B and C positive donors.

Results

Seroprevalence rates were found to be HIV (1.96 %), syphilis (2.15 %), hepatitis B (1.98 %) and hepatitis C (0.9 %). Majority donors were voluntary (70.37 %) and male (96.2 %). However seroprevalence rates showed no significant difference: voluntary (7.02 %), replacement (6.67 %) male (6.85 %) and female (6.95 %). HCV and HIV showed highest (29.6 %) while HBV and HCV (2.5 %) showed lowest concomitance. Serum ALT and bilirubin were not effective surrogate markers. No demographic or behavioral variable was found as a significant risk factor.

Conclusion

Thus, all donors need adequate privacy, information, counseling and motivation in order to reduce the seropositive rates in donors. Advent of sensitive tests renders surrogate markers redundant.     

Summary of the clinical significance of blood group alloantibodies

The knowledge of the potential clinical significance of alloantibodies to blood group antigens is essential for selecting appropriate red blood cell (RBC) products for transfusion. This article provides a summary of clinical and technical aspects of many alloantibodies.