Multicentre evaluation of the new ORTHO VISION® analyser

BACKGROUND

Implementation of fully automated analysers has become a crucial security step in the blood bank; it reduces human errors, allows standardisation and improves turnaround time (TAT).

OBJECTIVES

We aimed at evaluating the ease of use and the efficiency of the ORTHO VISION® Analyser (VISION) in comparison to the ORTHO AutoVue® Innova System (AutoVue) in six different laboratories.

METHODS

After initial training and system configuration, VISION was used in parallel to AutoVue following the daily workload, both automates being based on ORTHO BioVue® System column agglutination technology. Each participating laboratory provided data and scored the training, system configuration, quality control, maintenance and system efficiency. A total of 1049 individual samples were run: 266 forward and reverse grouping and antibody screens with 10 urgent samples, 473 ABD forward grouping and antibody screens with 22 urgent samples, 160 ABD forward grouping, 42 antibody screens and a series of 108 specific case profiles.

RESULTS

The VISION instrument was more rapid than the AutoVue with a mean performing test time of 27·9 min compared to 36 min; for various test type comparisons, the TAT data obtained from VISION was shorter than that from AutoVue. Moreover, VISION analysed urgent STAT samples faster. Regarding the ease of use, VISION was intuitive and user friendly.

CONCLUSIONS

VISION is a robust, reproducible system performing the most types of analytical determinations needed for pre-transfusion testing today, thus accommodating a wide range of clinical needs. VISION brings appreciated new features that could further secure blood transfusions.

Incidence and risk factors of post-engraftment invasive fungal disease in adult allogeneic hematopoietic stem cell transplant recipients receiving oral azoles prophylaxis

Studies that analyze the epidemiology and risk factors for invasive fungal disease (IFD) after engraftment in alloSCT are few in number. This single-center retrospective study included 404 alloSCT adult recipients surviving >40 days who engrafted and were discharged without prior IFD. All patients who received ⩾20 mg/day of prednisone were assigned to primary oral prophylaxis (itraconazole or low-dose voriconazole). The primary end point was the cumulative incidence (CI) of probable/proven IFD using the European Organization for Research and Treatment of Cancer and Mycoses Study Group (EORTC/MSG) criteria. The independent prognostic factors after multivariate analyses were used to construct a post-engraftment IFD risk score. The 1-year CI of IFD was 11%. The non-relapse mortality was 40% in those developing IFD and 16% in those who did not. The intent-to-treat analysis showed that 17% of patients abandoned the assigned prophylaxis. Age >40 years, ⩾1 previous SCT, pre-engraftment neutropenia >15 days, extensive chronic GVHD and CMV reactivation were independent risk factors. The post-engraftment IFD score stratified patients into low risk (0-1 factor, CI 0.7%), intermediate risk (2 factors, CI 9.9%) and high risk (3-5 factors, CI 24.7%) (P<0.0001). The antifungal prophylaxis strategy failed to prevent post-engraftment IFD in 11% of alloSCT. Our risk score could be useful to implement risk-adapted strategies using antifungal prophylaxis after engraftment.

Role of methylene blue-treated or fresh-frozen plasma in the response to plasma exchange in patients with thrombotic thrombocytopenic purpura

Twenty patients with thrombotic thrombocytopenic purpura (TTP) underwent plasma exchange using either standard fresh-frozen plasma (Group A, n = 13) or methylene blue-treated plasma (Group B, n = 7). Both groups presented similar characteristics except that bilirubin values were higher in Group A (P < 0.05). The complete remission rate was higher in Group A than B (69% versus 57%). The mean number of procedures was higher in Group B (21 +/- 7 versus 11 +/- 3, P < 0.01) and the mean duration of hospitalization was also longer (37 +/- 12 d versus 22 +/- 11 d; P < 0.01). Our study shows that the use of methylene blue-treated fresh-frozen plasma to treat TTP is associated with a higher number of plasma exchanges and greater transfusion requirements without improving clinical results.

Development of non-ABO RBC alloantibodies in patients undergoing allogeneic HPC transplantation. Is ABO incompatibility a predisposing factor?

BACKGROUND

Data from the appearance of RBC antibodies other than ABO in patients undergoing HPC transplantation are limited.

STUDY DESIGN AND METHODS

The incidence and specificity of non-ABO RBC alloantibodies are described in a series of 217 patients undergoing allogeneic HPC transplantation because of various hematologic malignancies.

RESULTS

Eight patients (3.7%) developed 10 antibodies after transplant. None of these patients had previously been immunized. Seven patients had one RBC antibody and one patient had three RBC antibodies. Antibody specificity were anti-Jk(b) (2 patients), -Kell (2), -M (2), -Le(b) (1), and -D (1). Finally, two patients had a panagglutinin. The mean time between transplant and antibody detection was 23 days (range, 16-672). The source of the HPCs, the conditioning regimen administered, and the type of GVHD prophylaxis administered did not influence the rate of antibody formation. On multivariate analysis, ABO blood group incompatibility (p = 0.005) and patient's age (p = 0.02) were the only two variables significantly associated with the development of RBC alloantibodies.

CONCLUSION

Patients undergoing allogeneic HPC transplantation are at risk of developing RBC-specific antibodies despite the immunosuppressive therapy administered. Antibody formation was more frequently observed in ABO-mismatched cases, which suggests a potential role of this incompatibility in facilitating antibody production.

[Report on the activity of the blood bank accreditation program (1987-1995)]

PURPOSE

To show the incidence of the deficiencies detected in the Blood Banks for the accreditation by the Transfusion Accreditation Committee (CAT), previously named PABAS.

MATERIALS AND METHODS

Analysis of the reports of the accreditation of 85 Blood Banks made by the PABAS during the period 1987-1995.

RESULTS

Eighty-five (20.8%) of the 407 Community Blood Centers, Hospital-Based Blood Banks and Transfusional Services of Spain had been surveyed. There were 244 deficiencies, of which 31 (12.7%) were of the equipment, 114 (46.7%) of the procedures used, and 99 (40.6%) of the documentation. The activities with more incidence of faults were: Control of the temperatures of the storage of units 53 (21.7%), label of the components 38 (15.5%), quality system of the institution surveyed 32 (13.1%), transfusional procedures 30 (12.3%), and on the procedure of the selection of donors 29 (11.9%). By contrary, the areas of work with fewer incidences of faults were those related with the collection of the blood and components 10 (4.1%) and the laboratory 14 (5.7%).

CONCLUSIONS

Low percentage of the Community Blood Centers, Hospital-Based Blood Banks and Transfusional Services, which ask to be accredited by the Transfusion Accreditation Committee. The 83.7% of the errors detected are of the procedures and documentation, which could be easily corrected by the training and continuous improving of the quality, and without need of new inversions in equipment.

Severe hemolytic anemia due to multiple red cell alloantibodies after an ABO-incompatible allogeneic bone marrow transplant

BACKGROUND

A patient who received an ABO-incompatible allogeneic bone marrow transplant experienced three episodes of immune hemolytic anemia due to multiple red cell (RBC) alloantibodies.

CASE REPORT

A 41-year-old man with chronic myeloid leukemia received an ABO-incompatible bone marrow graft from his HLA-identical brother. Selective removal of RBCs from donor marrow before transfusion was performed by centrifugation using a continuous-flow blood cell separator. The patient was given group O Rh-positive RBCs and group A Rh-positive platelets. Prophylaxis for graft-versus-host disease consisted of cyclosporine and methotrexate. The patient experienced three hemolytic episodes, on Days 21, 35, and 160 which were due to different RBC alloantibodies (anti-K, anti-Jk(b), anti-M, IgG anti-A) produced by host lymphocytes surviving the conditioning regimen.

RESULTS

The patient was group O, Jk(b-), and the marrow donor was group A, Jk(b+). After the first hemolytic episode (Day 21), immunohematologic studies showed group O RBCs and a positive direct antiglobulin test (IgG+, C3d+). Antibody screening test and eluate studies detected anti-M, anti-Jk(b), and anti-K. During the second hemolytic episode (Day 35), the patient's blood group showed a mixed population of group A and group O RBCs. The direct antiglobulin test was positive (IgG+, C3d+). Anti-M, anti-Jk(b), and IgG anti-A were detected in the serum. Eluates made from the recipient's RBCs showed the same specificity as serum antibodies. During the third hemolytic episode (Day 160), a mixture of group O and group A RBCs was still present, the direct antiglobulin test was positive (IgG+, C3d-), and anti-Jk(b) and IgG anti-A were observed in the serum and in an eluate made from the patient's RBCs.

CONCLUSION

This is the first reported case of severe immune hemolytic anemia due to multiple RBC alloantibodies after an allogeneic bone marrow transplant. The time of appearance and the specificity of the antibodies strongly suggest that they were produced by residual recipient lymphoid cells.

[Immunohematologic study and transfusion approach to patients with public antibodies]

OBJECTIVES

To analyze the different immunohematologic studies required to identify anti-red cell antibodies directed against high incidence antigens and comment the best tranfusion management.

PATIENTS AND METHODS

Five patients with suspected anti-red cell alloantibodies directed against high frequency antigens are reported. After a positive antibody screening test (AST), an agglutination test with a commercial panel of 24 red cells was performed. Red cells were treated with proteolytic enzymes and AET to try to identify the circulating antibody. However, it was necessary to send the samples to reference laboratories for definitive identification. In order to evaluate the haemolytic potential of the antibody serum samples were treated with DTT and immunoglobulin subtype was studied with the capillary agglutination test. Finally, we analyze the half life of Cr51 labelled red cells. To obtain compatible blood for transfusion, autologous transfusion and cross-match with blood from direct relatives were performed.

RESULTS

AST was positive in every case. A decrease in the agglutination test was observed after ficin treatment in two patients, and an increase in the remaining. The treatment of red cells with ZZAP and AET resulted in a decrease of agglutination in three cases and an increase in the remaining two. Specificity of the antibodies was as follows: anti-Cellano (two cases), anti-Ku (one case) and anti-Yta (two cases). Anti-Kell antibodies were IgG1 and anti-Cartwright antibodies were IgG4. One patient was transfused with autologous blood alone, another patient received compatible blood from direct relatives. A third patient was transfused both with autologous and allogeneic compatible blood. The fourth patient did not need red cell transfusion and, finally the last patient had to be transfused with incompatible blood but no postransfusion haemolysis was observed.

CONCLUSIONS

In patients with anti-red cell antibodies against high-frequency antigens, red blood cells treatment with proteolytic enzymes (ZZAP, ficin) and AET are useful techniques to approach to their identification. Beside this, the study of type and subtype of Ig are necessary to know the haemolytic activity of the antibody. Regarding the transfusional management, autologous transfusion, crossmatch with blood from direct relatives and cryopreservation of compatible blood are the most adequate attitudes to cover future needs.