Treatment of severe fetomaternal alloimmune thrombocytopenia with compatible frozen-thawed platelet concentrates.
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Antigens, Human Platelet↗
Biomedical subjects
P Bierling
Publications and source records attributed to P Bierling.
The nonexpression of CD36 on reticulocytes and mature red blood cells does not modify the clinical course of patients with sickle cell anemia.
It is thought that an increase in the adhesion of circulating reticulocytes to the vascular endothelium may initiate the vascular occlusion underlying the painful crises and organ failures typical of sickle cell disease (SCD). At least 2 receptors, usually present on reticulocytes, seem to be involved in this adhesion process: glycoprotein CD36 (glycoprotein IV) and integrin alpha(4)beta(1) (very late activation antigen--4). Recently, a high frequency of the platelet CD36--deficient phenotype was reported in black Africans. The frequency of this deficiency was similar in subjects with and without SCD. The role of CD36 in vaso-occlusion was then investigated by comparing the clinical course in 2 groups of black Africans homozygous for hemoglobin S, with and without CD36 deficiency, but similar in age, sex, geographical origin, number of alpha-globin genes, and beta-globin gene haplotype. Flow cytometry showed that CD36 was absent from the circulating red blood cells and reticulocytes of platelet CD36--deficient individuals but present on those from patients with normal platelet CD36 expression, and that alpha(4)beta(1) integrin levels were similar on the reticulocytes of the 2 groups. Neither clinical severity, as evaluated by the frequency and characteristics of vaso-occlusive events, nor biological data differed significantly in the 2 groups of patients. Finally, although CD36 has been suggested to play a critical role in the pathogenesis of vaso-occlusion, this study, despite including only a small number of patients, supports the idea that the modulation of expression of a single type of adhesion molecule is insufficient to counteract the pathological process leading to vaso-occlusion in SCD patients. (Blood. 2001;98:966-971)
Adolescent↗
Plateletpheresis concentrates produced with the COMTEC cell separator: the French experience.
The latest generation of cell separators such as Trima (Gambro), Amicus (Baxter) and AS-TEC 204 (Fresenius), allow the collection of leucocyte-reduced platelet concentrates without secondary filtration. Fresenius has recently developed the COMTEC cell separator whose performance has been evaluated by several teams in France. This new cell separator is an improved version of the Fresenius AS-TEC 204 cell separator, designed to allow more efficient platelet collections. This study reports on the experience of six French teams (from Bordeaux, Clermont-Ferrand, Creteil, Dijon, Lille and Nancy) who obtained 696 leucocyte-reduced plateletpheresis concentrates in the course of collection using the new Fresenius COMTEC cell separator. All healthy volunteer donors fulfilled French selection criteria for platelet apheresis. Donors were eligible if they had suitable venous accesses, if their bodyweight was *50 kg and if their pre-apheresis platelet count was >150 x 10(9) l(-1). Between 4606 and 5229 ml of blood were processed. The mean volume of the platelet concentrates was between 439 and 493 ml (mean 460 +/- 63 ml). The platelet yield was of the order of 5.18 +/- 1.02 x 10(11) with only one platelet concentrate below the norm of 2 x 10(11) platelets (0.91 x 10(11)). No plausible explanation for this was found. The residual leucocyte levels conform to current norms. The platelet concentrates contained less than 1 x 10(6) leucocytes per concentrate (mean 0.233 +/- 0.150 x 10(6) leucocytes) in more than 97% of the components produced with >95% statistical confidence. The efficacy of the cell separator (52.44 +/- 7.35%) is comparable to that of other separators. The Fresenius COMTEC cell separator makes it possible to obtain leucocyte-reduced platelet concentrates which comply with current standards both in terms of platelet content and residual leucocyte level.
Adult↗
High resolution HLA class I and II typing and CTLp frequency in unrelated donor transplantation: a single-institution retrospective study of 69 BMTs.
UNLABELLED: The results of unrelated donor transplantation (URD-BMT) are difficult to analyze since the continuous advances in HLA typing technology allow the detection of new mismatches unknown at the time of transplantation. We sought to confirm that matched recipient-donor pairs are in fact often mismatched when advanced HLA typing techniques are used. We retrospectively studied the impact of the results of high resolution HLA typing for HLA class I (-A, -B, -C) and HLA class II (-DR, -DQ, -DP) loci, and cytotoxic T lymphocyte precursor (CTLp) frequency, on the outcome of 69 URD-BMT procedures. At the time of transplant, six (6/69) and two (2/69) donor-recipient pairs were mismatched for HLA class I (-A and -B by serology) and HLA class II, respectively, while one pair was mismatched for both HLA class I and II. Using high resolution DNA typing, HLA class I mismatches were found in 31 (45%) pairs and HLA class II mismatches in nine (13%) pairs. Twenty-three of the 69 pairs were HLA-C mismatched. Low CTLp frequencies were found among the 19 HLA class I matched pairs tested, and also in 5/14 mismatched pairs (of whom three had severe aGVHD). The overall survival of the cohort was 28 +/- 6%. Among the 33 patients who were fully matched with their donors, the survival rate was 66% in the 18 patients with a standard hematological risk and 9% in the 15 high risk patients. Only two of the 33 patients developed severe aGVHD, and only one had graft rejection. Among the 36 mismatched pairs, the survival rate was 31% in the 13 patients with a standard hematological risk and 8% in the 23 high risk patients. Sixteen of these 36 patients died from severe aGVHD and four had graft failure or rejection. Three of the 10 patients with only an HLA-C mismatch died from severe aGVHD, and two had graft rejection. IN CONCLUSION: (1) donor-recipient matching based on high resolution HLA class I and II DNA typing is associated with significantly better outcome after URD-BMT; (2) the results of URD-BMT with classical GVHD prevention are comparable to those of geno-identical BMT when donor and recipient are fully matched for HLA-A, -B, -C, -DRB1 and -DQB1 on the basis of high resolution typing; (3) CTLp frequencies do not correlate constantly with HLA class I matching, and our results fail to show that CTLp assay can distinguish between permissible and non-permissible class I mismatches; (4) clinical trials involving donor-recipient pairs with known HLA class I mismatches are needed to improve aGVHD prevention without increasing graft failure rate.
Adult↗
Multicenter trial of one HLA-DR-matched or mismatched blood transfusion prior to cadaveric renal transplantation.
BACKGROUND: The beneficial effect of blood transfusions before cadaveric renal transplantation on allograft survival, although previously well documented, has become controversial in light of their adverse effects. Recently, it has been suggested that their clinical benefits are due to HLA-DR sharing between the blood donor and recipient. METHODS: In this prospective study, 144 naive patients were randomly assigned to receive one unit of blood matched for one-HLA-DR antigen (N = 49), or one unit of mismatched blood (N = 48), or to remain untransfused (N = 47). Graft survival and acute rejection rate were analyzed in 106 cadaveric renal allograft recipients receiving the same immunosuppressive protocol. RESULTS: Graft survival was similar in the three groups at one and five years: 91.7 and 80% in untransfused patients, 90.3 and 79.3% in patients transfused with one DR-antigen-matched unit, and 92.3 and 83.7% in patients transfused with HLA-mismatched blood. The difference in the incidence of six-month post-transplant acute rejections was not statistically significant in the three groups: 12 out of 36, 33.3% in nontransfused patients; 6 out of 31, 19.4% in patients transfused with one DR-matched blood; and 13 out of 39, 33.3% in patients transfused with mismatched blood. CONCLUSION: The results of our prospective randomized trial showed that in a population of naive patients, one transfusion mismatched or matched for one HLA-DR antigen given prior to renal transplantation had no significant effect on the incidence and severity of acute rejection, and did not influence overall long-term graft outcome. Considering the potentially deleterious adverse effects of blood transfusions, the costs, and the considerable logistical efforts required to select and type blood donors, such a procedure cannot be recommended in a routine practice for patients awaiting cadaveric kidney transplantation.
Acute Disease↗
Screening for autoimmune markers is unnecessary during follow-up of adults with autoimmune thrombocytopenic purpura and no autoimmune markers at onset.
In an attempt to evaluate the frequency of autoimmune markers in autoimmune thrombocytopenic purpura (AITP) and to determine if autoimmune markers in patients with isolated AITP were associated with particular disease manifestations, we analyzed records of 122 consecutive adults with AITP. Twenty-nine patients (24%) had significant titers of one or several autoimmune markers at AITP onset. Among them, 16 (13%) had antinuclear antibodies. The presence of autoimmune markers did not correlate with presenting feature, response to treatment or long-term outcome of AITP. Six patients (5%) developed seven autoimmune diseases during follow-up, comprising systemic lupus erythematosus, an antiphospholipid syndrome, autoimmune haemolytic anemia (n = 2), Grave's disease, Hashimoto's disease and primary biliary cirrhosis. At AITP onset, three of these patients had isolated biological markers of the autoimmune disease they later developed. The annual average incidence rate of autoimmune diseases was 1% per patient-year in the entire group and 0.4% in the group of patients with no autoimmune markers at AITP onset. This low rate is probably due to careful assessment at diagnosis for concomitant overt autoimmune disease. We recommend extensive screening for autoimmune markers at AITP onset, and careful follow-up of patients with autoimmune markers. Routine screening for autoimmune markers during AITP follow-up is not necessary for patients with no autoimmune markers at AITP onset. Systemic lupus erythematosus (SLE) and other autoimmune disorders can complicate autoimmune thrombocytopenic purpura (AITP) or be diagnosed concomitantly with otherwise unremarkable AITP (1, 2). However, the frequency and prognostic value of isolated autoimmune markers (i.e. not associated with an autoimmune disorder), particularly antinuclear antibodies (ANA) at AITP onset or during follow-up is controversial (3-8). For example, the committee organized by George et al. (9) to write guideline on the diagnosis and treatment of AITP stated that the search for ANA and lupus anticoagulant were of "uncertain appropriateness at diagnosis and during follow-up". In an attempt to help practicians to make decisions, we analyzed the frequency of autoimmune markers and autoimmune disorders at onset and during the follow-up in 122 adults with AITP and no overt autoimmune disease at diagnosis. These consecutive patients were followed by the same physician for a mean period of 6 years, and had routine screening tests for autoimmune markers and disorders at onset, before steroid therapy, and regularly during follow-up.
Adolescent↗
Lack of relevance of the acetylator status on dapsone response in chronic autoimmune thrombocytopenic purpura.
Dapsone provides an alternative treatment for patients with chronic autoimmune thrombocytopenic purpura (AITP) who had inadequate response to conventional therapy. However, the efficacy of this treatment is achieved in only 50% of patients. Dapsone is partly metabolized by the polymorphic N-acetyltransferase 2% and 50% of Caucasian patients show a genetically determined slow acetylator phenotype. The aim of our study was to investigate the influence of the acetylator status on dapsone efficacy in patients with chronic AITP. Nineteen caucasian adults with chronic AITP, previously treated by dapsone, were included in the study. Acetylator phenotype was determined by using a caffeine urinary test. Among the fourteen fast acetylator patients, eight patients exhibited positive response to dapsone and six patients did not. Among the five slow acetylator patients, one patient displayed a positive response to dapsone. Comparison of data by using the Fisher's exact test did not reach statistical significance. Our results do not support a relationship between dapsone efficacy and acetylator status in adults with chronic AITP.
Acetylation↗
[Intravenous immunoglobulins and autoimmune thrombopenic purpura].
OBJECTIVE: To determine the usefulness of intravenous immunoglobulin in the treatment of autoimmune thrombocytopenic purpura (AITP). RESULTS: IVIg infusion is an important agent in managing AITP because most patients experienced a rapid increased platelet count. Its precise place in the management of these patients is however controversial, particularly on account of its high cost and transient effect. It is indicated in the severe form of the disease or before surgery in corticoresistant patients. PERSPECTIVE: Prospective studied are mandatory to compare the efficacy of IVIg and high dose corticosteroids in this indication.
Anti-Inflammatory Agents↗
The response to high-dose intravenous immunoglobulin or steroids is not predictive of outcome after splenectomy in adults with autoimmune thrombocytopenic purpura.
The response to high-dose intravenous immunoglobulin (IVIg) was recently reported to be predictive of outcome after splenectomy in patients with autoimmune thrombocytopenic purpura (AITP). We analysed the records of 75 adults with chronic AITP who received IVIg and subsequently underwent splenectomy. There was no significant difference in the response rate to splenectomy according to whether or not patients had responded to IVIg (81% v 67%, P = 0.36). Age, the time from diagnosis to splenectomy, and the response to steroids were also not significantly associated with outcome after splenectomy. These results indicate that the response to IVIg or steroids is not predictive of the efficacy of splenectomy.
Adolescent↗
Intravenous immunoglobulin for adults with autoimmune thrombocytopenic purpura: results of a randomized trial comparing 0.5 and 1 g/kg b.w.
Since the first reports demonstrating the ability of a total dose of 2 g/kg body weight (b.w.) of intravenous immunoglobulin (IVIg) to increase the platelet count in patients with autoimmune thrombocytopenic purpura (AITP), the optimal dose has remained controversial. We report the results of a randomized study which compared two low doses of IVIg (0.5 g/kg b.w., group A, n = 19, and 1 g/kg b.w., group B, n = 18) in 37 adults with AITP and platelet count <50 x 109/l, in preparation for surgery or in a situation with a risk of bleeding. On day 4 the proportion of responses, defined by a platelet count > 80 x 109/l and at least twice the initial platelet count, was significantly higher in the group receiving 1 g/kg b.w. (12/18 in group B versus 4/19 in group A, P = 0.005). All but one of the day 4 responders had already responded on day 3. The daily changes in the platelet count from the beginning of IVIg treatment were larger in group B, with a significant difference relative to group A on day 3 (92 x 109/l in group B versus 50 x 109/l in group A, P = 0.03) and on day 4 (106 x 109/l in group B versus 55 x 109/l in group A, P = 0.03). Patients who had not responded by day 4 subsequently received 1.5 g IVIg/kg b.w. (group A) or 1 g IVIg/kg b.w. (group B). A response was observed in 11/13 initial non-responders in group A, and in 2/6 initial non-responders in group B. Finally, on day 8, the proportion of responders was 78% (29/37) in the entire group and was similar in the two subgroups. In conclusion, (1) initial treatment with 1 g/kg b.w. of IVIg appeared to be more effective than 0.5 g/kg b.w. in adults with AITP; (2) infusion of a low dose of IVIg did not jeopardize the efficacy of IVIg reinfusion; (3) some adults who did not respond to 1 g IVIg/kg b.w. responded to a higher dose.
Adult↗
CD36 deficiency is frequent and can cause platelet immunization in Africans.
BACKGROUND: CD36 is expressed on several cell lineages. About 5 to 10 percent of Asians lack platelet membrane CD36 (pCD36), but the frequency of pCD36 deficiency in other ethnic groups is not known. Persons who are pCD36-negative are apparently healthy but can develop CD36 isoimmunization. STUDY DESIGN AND METHODS: The pCD36 phenotype was studied in 1885 subjects belonging either to a group of 1127 healthy French blood donors (almost all of whom were white Europeans) or to a group of 758 patients of known ethnic origin. RESULTS: No pCD36-negative persons were found among the blood donors. Only 1 of the 301 white European patients was pCD36-negative. In contrast, 16 of the 206 sub-Saharan Africans was pCD36-negative, a proportion higher than that among that black Caribbeans (1/148, p<0.01). The frequency of pCD36-negative patients was similar in blacks with and without sickle cell disease. Monocyte CD36 (mCD36) expression was studied in 15 of 22 pCD36-negative individuals: it was <10 percent in 7 subjects (type I deficiency) and between 12 and 100 percent in 8 others (type II deficiency). Thirteen pCD36-negative individuals had risk factors for immunization, and 4 had anti-CD36. Some had a history resembling posttransfusion purpura (n = 2), platelet transfusion refractoriness (n = 1), and recurrent miscarriage (n = 1). No correlation was found between immunization and the amount of mCD36. Anti-CD36 from an immunized type II-deficient woman reacted with monocytes from normal controls but not with monocytes from type I- or type II-deficient individuals, and thus it is postulated that mCD36 could be structurally different in normal and type II CD36-deficient individuals. CONCLUSION: CD36 deficiency is frequent in sub-Saharan Africans; development of anti-CD36 can lead to serious complications in multiply transfused patients, such as those with sicke cell disease.
Adult↗
The treatment of patients with autoimmune thrombocytopenia with intravenous IgG-anti-D.
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Humans↗
Knowledge acquisition environment for the design of a decision support system: application in blood transfusion.
Blood transfusion is a medical domain where decision support systems (DSSs) could be very helpful to the physicians but must easily and continuously be maintained. We have developed a knowledge acquisition tool that allows the construction and the maintenance of such a system by the domain expert. The methodology used could be applied to another highly evolutive medical domain. In this paper, we detail our knowledge acquisition tool, its use and the final DSS obtained, which is fully integrated into our hospital information network.
Artificial Intelligence↗
[Transfusion of platelet concentrates].
Although a number of research have been realized in the aim of decreasing the use of platelet concentrates, these blood products remain absolutely necessary for patients with therapeutic aplasia and for some surgical patients. After the description of the main rules of platelet transfusion procedures, we will discuss some controversial issues: threshold value for platelet transfusion, platelet doses, place of curative and prophylactic strategies, refractoriness to platelet transfusion, HLA alloimmunization. Then we will focus our review on the future alternatives for platelet transfusion.
Blood Donors↗
Platelet transfusion: a dose-response study.
Early recommendations on prophylactic transfusion of thrombocytopenic patients involved a standard platelet dose of about 0.5 x 10(11)/10 kg body weight. Given the lack of data supporting this dose, we prospectively studied the dose response to platelet transfusions in adults and children with hematologic malignancies. Each patient received, in similar clinical conditions, a medium, high, and very high dose of fresh (< 24 hours old) ABO-compatible platelets, in the form of apheresis platelet concentrates (APC). For the adults, the medium dose was defined as APC containing between 4 and 6 x 10(11) platelets, the high dose between 6 and 8 x 10(11), and the very high dose > 8 x 10(11); for the children, the three doses corresponded to 2 to 4, 4 to 6, and > 6 x 10(11) platelets. The end points were the platelet increment, platelet recovery, and the transfusion interval, and the results were compared with a paired t-test. Sixty-nine adults and 13 children could be assessed. Recoveries in the adults were similar with the three doses (from 28% to 30%), but the high and very high doses led to a significantly better platelet increment (52 and 61 x 10(9)/L, respectively) than the medium dose (33 x 10(9)/L, P < .01). The main difference was in the transfusion interval, which increased with the dose of platelets transfused, from 2.6 days with the medium dose to 3.3 and 4.1 days with the high and very high doses, respectively (P < .01). The positive effect of the high dose was observed regardless of pretransfusional clinical status, but was more marked in patients with no clinical factors known to impair platelet recovery. In these patients, a platelet dose of 0.07 x 10(11) per kg of body weight led to a transfusion interval of more than 2 days in 95% of cases. In patients with clinical factors favoring platelet consumption, the proportion of transfusions yielding an optimal platelet increment and transfusion interval increased with the dose of platelets. The platelet dose-effect was also significant in the children, in whom the high and very high doses led to 1.5-fold to twofold higher posttransfusion platelet counts and transfusion intervals. We conclude that transfusion of high platelet doses can reduce the number of platelet concentrates required by thrombocytopenic patients and significantly reduce donor exposure.
Acute Disease↗
[Antiplatelet antibodies].
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Antibodies, Monoclonal↗
Irinotecan-induced immune thrombocytopenia.
BACKGROUND: Irinotecan is currently used as second-line chemotherapy for advanced colorectal cancer. We report a case of severe thrombocytopenia after Irinotecan, suggesting an immune mechanism, in a 53-year-old patient. PATIENTS AND METHODS: The patient's sera were screened for platelet antibodies with an indirect platelet immunofluorescence test (PIIFT). The monoclonal antibody immobilization of platelet antigen assay (MAIPA) was used to characterize the antibody target. RESULTS: We detected an IgG platelet antibody in the patient's serum in the presence of Irinotecan by means of PIIFT, and not in the presence of SN-38, its active metabolite. The specificity of the binding was asserted after CD32 MoAb blockade. The platelet binding site could not be strictly identified with MAIPA and immunoblotting but GpIIb/IIIa can be excluded after experiments with Glanzmann platelets. CONCLUSION: This case can be considered the first documented Irinotecan-induced immune thrombocytopenia.
Adenocarcinoma↗
Apparent reactivation of a red cell alloantibody in a healthy individual after G-CSF administration.
Granulocyte-colony stimulating factor (G-CSF) has been successfully administered to healthy subjects to mobilize peripheral blood stem cells (PBSC) for allogeneic transplantation. Adverse events are moderate. We report the first case of apparent reactivation of an alloantibody to a blood cell antigen (Jk(a)) after G-CSF administration to a healthy subject and its transmission to the PBSC transplant recipient; no concomitant reactivation of other alloantibodies was detected. This case raises questions on the effect of G-CSF on the immune system and its safety in healthy individuals.
Adjuvants, Immunologic↗