Immunohematological findings in myelodysplastic syndrome

Successful treatment of concurrent cold agglutinin disease and myelodysplastic syndrome

Herein, we describe a case of severe anemia presenting with myelodysplastic syndrome with cold agglutinin disease that was successfully treated by a moderate dose of steroids followed by cyclosporine. In patients with myelodysplastic syndrome, autoimmunity in erythroid cells is occasionally demonstrated, and autoimmune hemolytic anemia is seen in some patients. However, hemolytic anemia with cold agglutinin in patients with myelodysplastic syndrome is less common, and the effect of corticosteroids for autoimmune hemolytic anemia caused by cold agglutinin is thought to be limited. Although the elevated levels of reticulocytes and LDH are usually caused by ineffective hematopoiesis in myelodysplastic syndrome, clinicians should be aware of latent cold agglutinin disease. In the present case, in addition to the improvement of erythroid dysplasia, the corticosteroid-sparing effect on cold agglutinin disease may have played a role in the mechanism underlying the effectiveness of cyclosporine.

Transfusion Support of Patients with Myelodysplastic Syndromes

Patients with MDS often suffer from anemia, and less often thrombocytopenia, and thus are a frequently transfused population. Red blood cell (RBC) transfusion may be used to improve functional capacity and quality of life in this population, while platelet transfusion is typically used to decrease bleeding risk. Despite the frequency of transfusion in patients with MDS, there are few well-defined guidelines for RBC and platelet transfusion support in this patient population. Transfusion is not without risk-patients with MDS who are frequently transfused may develop alloantibodies to RBC antigens, which can lead to hemolytic transfusion reactions and delays in obtaining compatible RBCs. Regular communication between clinicians and blood bank physicians is crucial to ensure that patients with MDS receive the most appropriate blood products.

[Dysimmune manifestations associated with myelodysplastic neoplasms and chronic myelomonocytic leukaemias]

Systemic inflammatory or autoimmune diseases (SIAD) are observed in up to a quarter of patients with myelodysplastic syndromes (MDS) or chronic myelomonocytic leukemia (CMML), with a broad clinical spectrum including asymptomatic biological abnormalities, isolated inflammatory clinical manifestations (recurrent fever, arthralgia, neutrophilic dermatoses…) or identified systemic diseases (giant cell arteritis, recurrent polychondritis…). Recent advances in molecular biology have shed new light on the pathophysiological mechanisms that link inflammatory manifestations and myeloid hemopathies, particularly in VEXAS syndrome following the identification of somatic mutations in the UBA1 gene, or in neutrophilic dermatoses with the concept of myelodysplasia cutis. Although the presence of SIAD does not seem to affect overall survival or the risk of transformation into acute myeloid leukemia, their treatment remains a challenge given the frequent high level of corticosteroid dependence as well as the poor efficacy and tolerance (cytopenias, infections) of conventional immunosuppressive agents. Recent prospective data supports the interest of a therapeutic strategy using demethylating agents and notably azacitidine to target the pathological clone.

Somatic mutations show no clear association with red blood cell or human leukocyte antigen alloimmunization in de novo or therapy-related myelodysplastic syndrome

BACKGROUND

Myelodysplastic syndrome (MDS) is a marrow failure disease. As patients often require chronic transfusion, many develop red blood cell (RBC) alloimmunization or immune-mediated platelet refractoriness. MDS represents a spectrum of diseases with specific categorizations and genetic abnormalities, and we set out to determine if these characteristics predispose patients to antibody formation.

STUDY DESIGN AND METHODS

A natural language search identified MDS patients with pre-transfusion testing from 2015 to 2020. Marrow reports, cytogenetic results, and next-generation sequencing panels were gathered. Transfusion history and testing were collected from the laboratory information system.

RESULTS

The group consisted of 226 biopsy-proven MDS patients. The prevalence of RBC alloimmunization was 11.1% (25 of 226). Half (23 of 46) of all RBC alloantibodies were against Rh (C, c, E, e) and Kell (K) antigens. There was a relative enrichment for JAK2 positivity among the RBC alloimmunized group. A total of 7.1% (16 of 226) of patients had immune-mediated platelet refractoriness and had increased transfusion requirements (p ≤ 0.01). No disease type or genetic abnormality was significantly associated with alloimmunization or immune-mediated platelet refractoriness.

DISCUSSION

While JAK2 specific mutations were enriched among RBC alloimmunized patients, this association failed to reach statistical significance in our single-center cohort. Further study using larger patient cohorts is warranted. Overall, this cohort of MDS patients had very similar RBC alloimmunization prevalence and anti-RBC antibody specificities as other recent literature. Our data reinforce the finding that MDS patients are at greater risk for alloimmunization and support the use of extended phenotype matching for these at-risk patients.

Low-Risk Myelodysplastic Syndrome Revisited: Morphological, Autoimmune, and Molecular Features as Predictors of Outcome in a Single Center Experience

Low-risk myelodysplastic syndromes (LR-MDS) are a very heterogeneous disease, with extremely variable clinical features and outcome. Therapeutic strategies are still limited and mainly consist of erythropoiesis-stimulating agents (ESAs) and transfusion support. The contribution of molecular lesions and of autoimmune phenomena to pathogenesis and clinical course, including leukemic evolution, is a field of open investigation. We analyzed data from a cohort of 226 patients with LR-MDS followed at our center in the last 20 years, focusing on morphological, immunological (antiplatelets and anti-erythrocyte autoantibodies, anti-erythroblast antibodies), and molecular features. Hypoplastic bone marrow was found in 7% of the cases correlating with younger age, deeper cytopenia, lower dysplasia, and worse response to ESAs. A marker of autoimmunity was observed in 46% of the tested cases, who were younger, were less frequent dysplastic changes, and responded better to ESAs and steroids. Finally, 68% of the tested cases displayed at least one somatic mutation, most commonly SF3B1, TET2, ASXL1, and SRSF2, associated with older age, presence of neutropenia, and lower response to ESAs. Leukemic evolution (2.2%) was associated with presence of somatic mutations, and survival was favorably related to response to ESAs and transfusion independence. Overall, granular evaluation and re-evaluation are pivotal in LR-MDS patients to optimize clinical management.

Clinical Heterogeneity of the VEXAS Syndrome: A Case Series

The objective of this study is to describe the clinical features and outcomes of patients with the newly defined vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome. Nine men with somatic mutations in the UBA1 gene were identified; the most frequent variant was p.Met41Thr (7 of 9, 78%). The median age at VEXAS diagnosis was 74 (67, 76.5) years, and patients had a median duration of symptoms for 4 years before diagnosis. Refractory constitutional symptoms (88%), ear and nose chondritis (55%), and inflammatory arthritis (55%) were common clinical features. Vasculitis was noted in 44%. All patients had significantly elevated inflammatory markers and macrocytic anemia. Thrombocytopenia was present in 66% at diagnosis of VEXAS. Eight patients had bone marrow biopsies performed. All bone marrows were hypercellular, and there was vacuolization of the erythroid (100%) or myeloid precursors (75%). Glucocorticoids attenuated symptoms at prednisone doses ≥20 mg per day, but no other immunosuppressive agent showed consistent long-term control of disease. One patient with coexisting plasma-cell myeloma received plasma-cell-directed therapy with improvement of the inflammatory response, which is a novel finding. In conclusion, VEXAS syndrome is a clinically heterogeneous, treatment-refractory inflammatory condition caused by somatic mutation of the UBA1 gene. Patients often present with overlapping rheumatologic manifestations and persistent hematologic abnormalities. As such, internists and subspecialists, including pathologists, should be aware of this condition to avert diagnostic delay, now that the etiology of this syndrome is known.

Inflammatory and Immune Disorders Associated with Myelodysplastic Syndromes

Systemic auto-inflammatory or autoimmune diseases (SIADs) develop in up to a quarter of patients with myelodysplastic syndromes (MDS) or chronic myelomonocytic leukemia (CMML). With or without the occurrence of SIADs, the distribution of MDS subtypes and the international or CMML-specific prognostic scoring systems have been similar between MDS/CMML patients. Moreover, various SIADs have been described in association with MDS, ranging from limited clinical manifestations to systemic diseases affecting multiple organs. Defined clinical entities including systemic vasculitis, connective tissue diseases, inflammatory arthritis and neutrophilic diseases are frequently reported; however, unclassified or isolated organ impairment can also be seen. Although the presence of SIADs does not impact the overall survival nor disease progression to acute myeloid leukemia, they can help with avoiding steroid dependence and make associated adverse events of immunosuppressive drugs challenging. While therapies using steroids and immunosuppressive treatment remain the backbone of first-line treatment, increasing evidence suggests that MDS specific therapy (hypomethylating agents) and sparing steroids may be effective in treating such complications based on their immunomodulatory effect. The aim of this review was to analyze the epidemiological, pathophysiological, clinical and therapeutic factors of systemic inflammatory and immune disorders associated with MDS.

Hypoplastic Myelodysplastic Syndromes: Just an Overlap Syndrome?

Simple Summary

Hypoplastic myelodysplastic syndromes (hMDS) represent a diagnostic conundrum. They share morphologic and clinical features of both MDS (dysplasia, genetic lesions and cytopenias) and aplastic anemia (AA; i.e., hypocellularity and autoimmunity) and are not comprised in the last WHO classification. In this review we recapitulate the main clinical, pathogenic and therapeutic aspects of hypo-MDS and discuss why they deserve to be distinguished from normo/hypercellular MDS and AA. We conclude that hMDS may present in two phenotypes: one more proinflammatory and autoimmune, more similar to AA, responding to immunosuppression; and one MDS-like dominated by genetic lesions, suppression of immune surveillance, and tumor escape, more prone to leukemic evolution.

Abstract

Myelodysplasias with hypocellular bone marrow (hMDS) represent about 10–15% of MDS and are defined by reduced bone marrow cellularity (i.e., <25% or an inappropriately reduced cellularity for their age in young patients). Their diagnosis is still an object of debate and has not been clearly established in the recent WHO classification. Clinical and morphological overlaps with both normo/hypercellular MDS and aplastic anemia include cytopenias, the presence of marrow hypocellularity and dysplasia, and cytogenetic and molecular alterations. Activation of the immune system against the hematopoietic precursors, typical of aplastic anemia, is reckoned even in hMDS and may account for the response to immunosuppressive treatment. Finally, the hMDS outcome seems more favorable than that of normo/hypercellular MDS patients. In this review, we analyze the available literature on hMDS, focusing on clinical, immunological, and molecular features. We show that hMDS pathogenesis and clinical presentation are peculiar, albeit in-between aplastic anemia (AA) and normo/hypercellular MDS. Two different hMDS phenotypes may be encountered: one featured by inflammation and immune activation, with increased cytotoxic T cells, increased T and B regulatory cells, and better response to immunosuppression; and the other, resembling MDS, where T and B regulatory/suppressor cells prevail, leading to genetic clonal selection and an increased risk of leukemic evolution. The identification of the prevailing hMDS phenotype might assist treatment choice, inform prognosis, and suggest personalized monitoring.

Red Blood Cell Alloimmunization in Korean Patients With Myelodysplastic Syndrome and Liver Cirrhosis

Red blood cell (RBC) alloimmunization varies across human populations and ethnic groups. We evaluated the characteristics of RBC alloimmunization and compared the risk of alloimmunization in Korean patients with myelodysplastic syndrome (MDS) and liver cirrhosis (LC), two representative diseases in which chronic transfusion is required. In total, 115 MDS patients and 202 LC patients transfused with RBCs between 2013 and 2015 were retrospectively included. Twenty patients (6.3%) were newly alloimmunized (five MDS patients, 4.3%; 15 LC patients, 7.4%). The median number of RBC units transfused in alloimmunized patients was nine (interquartile range, 4–15 units). As the number of transfused RBC units increased, the cumulative risk of alloimmunization was higher in LC than in MDS patients (P=0.001). The most common alloantibody detected in patients was anti-E (45%), followed by anti-c (17%), anti-e (10%), anti-C (7%), anti-Fy^b (7%), and anti-Jk^a (7%). The present data indicate the need for matching of extended RBC antigens (Rh, Duffy, and Kidd systems) for chronically transfused patients with MDS and LC in Korea.

Autoimmune manifestations associated with myelodysplastic syndromes

Autoimmune disorders (ADs) are encountered in 10 to 20% of patients with myelodysplastic syndromes (MDS). Available data suggest that ADs concern more often younger patients with higher risk IPSS. MDS subtypes associated with ADs are mainly MDS with single lineage dysplasia (MDS-SLD) and MDS with excess blasts (MDS-EB). Various types of ADs have been described in association with MDS, ranging from limited clinical manifestations to systemic diseases affecting multiple organs. Defined clinical entities as vasculitis, connective tissue diseases, inflammatory arthritis, and neutrophilic diseases are frequently reported; however, unclassified or isolated organ impairment can be seen. In general, ADs do not seem to confer worse survival, although certain ADs may be associated with adverse outcomes (i.e., vasculitis) or progression of MDS (Sweet syndrome). While steroids and immunosuppressive treatment (IST) remain the backbone of first-line treatment, increasing evidence suggests that MDS-specific therapy as hypomethylating agents, based on their immunomodulatory effect, may be effective in treating these complications and for sparing steroids.

Red cell alloimmunization is associated with development of autoantibodies and increased red cell transfusion requirements in myelodysplastic syndrome

Up to 90% of patients with a myelodysplastic syndrome require red blood cell transfusion; nevertheless, comprehensive data on red cell alloimmunization in such patients are limited. This study evaluates the incidence and clinical impact of red cell alloimmunization in a large cohort of patients with myelodysplastic syndrome registered in the statewide South Australian-MDS registry. The median age of the 817 patients studied was 73 years, and 66% were male. The cumulative incidence of alloimmunization was 11%. Disease-modifying therapy was associated with a lower risk of alloimmunization while alloimmunization was significantly higher in patients with a revised International Prognostic Scoring System classification of Very Low, Low or Intermediate risk compared to those with a High or Very High risk (P=0.03). Alloantibodies were most commonly directed against antigens in the Rh (54%) and Kell (24%) systems. Multiple alloantibodies were present in 49% of alloimmunized patients. Although 73% of alloimmunized patients developed alloantibodies during the period in which they received their first 20 red cell units, the total number of units transfused was significantly higher in alloimmunized patients than in non-alloimmunized patients (90±100 versus 30±52; P<0.0001). In individual patients, red cell transfusion intensity increased significantly following alloimmunization (2.8±1.3 versus 4.1±2.0; P<0.0001). A significantly higher proportion of alloimmunized patients than non-alloimmunized patients had detectable autoantibodies (65% versus 18%; P<0.0001) and the majority of autoantibodies were detected within a short period of alloimmunization. In conclusion, this study characterizes alloimmunization in a large cohort of patients with myelodysplastic syndrome and demonstrates a signficant increase in red cell transfusion requirements following alloimmunization, most probably due to development of additional alloantibodies and autoantibodies, resulting in subclinical/clinical hemolysis. Strategies to mitigate alloimmunization risk are critical for optimizing red cell transfusion support.

Red blood cell alloimmunization in 184 patients with myeloid neoplasms treated with azacitidine - A retrospective single center experience

Alloimmunization to Red Blood Cell (RBC) antigens frequently occurs in patients with myeloid neoplasms (AML, MDS and CMML) and potentially poses the patient at risk for delayed hemolytic transfusion reactions and limited supply of compatible RBC-units. However, there is comparatively little data on transfusion associated characteristics in this patient cohort. We therefore retrospectively analyzed transfusion requirements and clinical outcomes of 184 patients with myloid neoplasms treated with azacitidine at the Paracelsus Medical University Salzburg, which were included in the Austrian Registry of Hypomethylating Agents. The mean blood component requirements for AML, MDS and CMML were 39.8, 67.4 and 31.4 RBC units and 31.7, 27.6 and 19.1 platelet (PLT) units respectively. In spite of an extended and stringent RBC unit matching policy (ABO, RhD, RhCcEe and K antigens), 20 (11%) patients formed at least one alloantibody ("allo-group"), whereas 164 patients (89%) did not ("non-allo-group"). The most frequent antibody specificity was anti-E, followed by anti-Wra -Lua, -D, -C and -Jka. Alloimmunization was associated with higher numbers of transfused RBC units (68 vs. 38; p=0.001), as well as with longer time under transfusion (16.7 vs. 9.4 months; p=0.014). Median overall survival (OS) did not differ significantly between the "allo"- and "non-allo-group".

Cancer type predicts alloimmunization following RhD-incompatible RBC transfusions

BACKGROUND

Immunosuppressed, RhD-negative oncology patients tend to have lower rates of sensitization to the D antigen when they receive transfusion with RhD-positive blood components. Clinical factors associated with alloimmunization to the D antigen in RhD-negative oncology patients when they receive transfusion with RhD-positive red blood cells (RBCs) have not been well defined.

STUDY DESIGN AND METHODS

This was a 4-year, retrospective analysis identifying RhD-negative oncology patients who received RhD-positive RBCs and were not previously alloimmunized to the D antigen. Age, sex, race, ABO group, primary oncology diagnosis, and numbers of RhD-incompatible RBC transfusions were recorded. The association between antibody formation and clinical factors was studied. The incidence of alloanti-D was calculated from a subsequent antibody-detection test performed at least 28 days after receipt of the first transfusion of RhD-positive RBCs.

RESULTS

In total, 545 RhD-negative oncology patients received 4295 RhD-positive RBC transfusions. Of these, 76 (14%) became alloimmunized to the D antigen. Diagnosis type was the only factor significantly associated with responder status. The logistic regression model indicated that patients who had myelodysplastic syndrome or solid malignancies were more likely to be responders than those who had acute leukemia.

CONCLUSION

We measured a 14% sensitization rate to the D antigen in our RhD-negative oncology population. The rate of alloimmunization was higher in patients who had solid cancers (22.6%) or myelodysplastic syndrome (23%) compared with those who had other hematologic malignancies (7%). Knowledge of diagnoses that predispose to RhD alloimmunization enables better utilization of RhD-negative RBCs during times of shortage.

Treatments for hematologic malignancies in contrast to those for solid cancers are associated with reduced red cell alloimmunization

Red cell alloimmunization may induce severe hemolytic side effects. Identification of risk-modifying conditions will help tailor preventative strategies. This study aims to quantify the associations of hematologic malignancies and solid cancers with red cell alloimmunization in patients receiving red cell transfusions. We performed a nested multicenter case-control study in a source population of 24,063 patients receiving their first and subsequent red cell transfusions during an 8-year follow-up period. Cases (n=505), defined as patients developing a first transfusion-induced red cell alloantibody, were each compared with 2 non-alloimmunized controls (n=1010) who received a similar number of red cell units. Using multivariate logistic regression analyses, we evaluated the association of various malignancies and treatment regimens with alloimmunization during a delineated 5-week risk period. The incidence of alloimmunization among patients with acute (myeloid or lymphoid) leukemia and mature (B- or T-cell) lymphoma was significantly reduced compared to patients without these malignancies: adjusted relative risks (RR) with 95% confidence interval (CI) 0.36 (range 0.19-0.68) and 0.30 (range 0.12-0.81). Associations were primarily explained by immunosuppressive treatments [RR for (any type of) chemotherapy combined with immunotherapy 0.27 (95%CI: 0.09-0.83)]. Alloimmunization risks were similarly diminished in allogeneic or autologous stem cell transplanted patients (RR 0.34, 95%CI: 0.16-0.74), at least during the six months post transplant. Alloimmunization risks of patients with other hematologic diseases or solid cancers, and their associated treatment regimens were similar to risks in the general transfused population. Our findings suggest that, in contrast to malignancies in general, hemato-oncological patients treated with dose-intensive regimens have strongly diminished risk of red cell alloimmunization.

Impact of azacitidine on red blood cell alloimmunisation in myelodysplastic syndrome

BACKGROUND

The incidence of alloimmunisation in myelodysplastic syndromes (MDS) during the era of supportive treatment ranges from 9 to 56%. However, it is unknown if the widespread use of hypomethylating agents has changed the risk of immunisation. The aim of this study is to evaluate the impact of azacitidine (AZA) therapy on red blood cell (RBC) alloimmunisation in transfused patients with MDS, myelodysplastic syndromes/myeloproliferative syndromes (MDS/MPS) and secondary acute myeloid leukaemia (AML).

MATERIAL AND METHODS

We have analysed retrospectively all patients with MDS, MDS/MPS and secondary AML from MDS, who received their first transfusion in our hospital between January 1995 and December 2014. We have assessed the impact of age, sex, RBC and platelets units transfused, and AZA treatment on developing alloantibodies.

RESULTS

In our study, the number of RBC units transfused increased the risk of developing alloantibodies. However aging and the treatment with AZA were associated with a lower rate of alloimmunisation.

DISCUSSION

Patients with MDS, MDS/MPS and secondary AML who received treatment with AZA developed RBC antibodies at a lower rate than control group. We suggest that aging and immunosuppression due to AZA therapy could develop an immunological tolerance with a weak response to allotransfusions.

The Influence of Clinical and Biological Factors on Transfusion-Associated Non-ABO Antigen Alloimmunization: Responders, Hyper-Responders, and Non-Responders

In the context of transfusion medicine, alloimmunization most often refers to the development of antibodies to non-ABO red blood cell (RBC) antigens following pregnancy, transfusion, or transplantation. The development of RBC alloantibodies can have important clinical consequences, particularly in patients who require chronic transfusions. It has been suggested that alloimmunization is more common in some clinical circumstances and patient populations than in others. As such, individuals that develop alloantibodies are frequently referred to as 'responders' in the medical literature. In contrast, individuals that do not develop alloantibodies despite repeated exposures to non-self blood group antigens have been referred to as 'non-responders'. The purpose of this article is to review the phenomenon of RBC alloimmunization in the context of responders and non-responders to: i) establish a basic framework for alloimmunization as reported across several diverse patient populations; ii) more fully explore literature reports which support the concept of responders/non-responders regarding blood group antigen alloimmunization; iii) summarize the mechanisms that have been shown to predispose an individual to alloimmunization to determine how these factors may differentiate 'responders' from 'non-responders'; and iv) briefly discuss some practical approaches to prevent alloimmunization in patients who may be prone to alloantibody development.

[Auto-immune diseases and cancers. Second part: auto-immune diseases complicating cancers and their treatment]

Autoimmune diseases may reveal or occur during the course of a neoplasia or its treatment. Autoimmune cytopenia, especially haemolytic anaemia, is common in lymphoproliferative disorders such as chronic lymphoid leukemia. The link between cancer and myositis is well established. Dermatomyositis is associated with an increased relative risk of cancer of 3.4 to 4.4. A combination of detection of antibodies against p155 and TEP-computed tomography may be the best approach to ascertain the presence of occult malignancy in patients with dermatomyositis. A cutaneous or a systemic vascularitis may reveal a cancer, most often a haematological malignancy such as hairy cell leukemia. Paraneoplastic polyarthritis have been described in particular with adenocardinoma of the lungs. Underlying neoplasia should be considered in male smokers patients with new onset polyarthritis and poor health status. The prevalence of autoimmune conditions in myelodysplastic syndromes is 10 to 30%. Vasculitis and relapsing polychondritis are the most commonly reported manifestations. Immune manifestations can also be related to treatment. The most common treatment complications are autoimmune haemolytic anaemia with fludarabine and thyroiditis related to interferon and cervical radiotherapy.

Myelodysplastic syndrome and autoimmunity: a case report of an unusual presentation of myelodysplastic syndrome

Myelodysplastic syndrome (MDS) commonly presents asymptomatically or with symptomatic cytopenias. However, autoimmune phenomena in association with MDS have been well described in several case reports and case series. Typically, these autoimmune phenomena take the form of vasculitides, arthritis, connective tissue diseases, pulmonary infiltrates, or polymyalgia rheumatica. We present the case of a woman with MDS (karyotype 46,XX,+1,der(1;7)(q10;p10)[20], that evolved with an additional trisomy 8 clone) and a novel spectrum of autoimmune diseases including acute fibrinous and organizing pneumonia (AFOP) and lacrimal gland pseudotumor.

Additional red blood cell alloantibodies after blood transfusions in a nonhematologic alloimmunized patient cohort: is it time to take precautionary measures?

BACKGROUND

Red blood cell (RBC) alloimmunization is common in transfused patients. Most studies report on the rate of alloimmunization in chronically transfused patients, which can be as high as 60 percent. Less is known on the incidence of clinically relevant antibodies in accidentally transfused patients. Because the probability of repeat transfusion increases with longer life expectancy, it was wondered to which extend non-chronically transfused alloimmunized patients are prone to form additional antibodies after repeat transfusion events.

STUDY DESIGN AND METHODS

A 20-year retrospective multicenter study was performed analyzing additional alloantibody formation, against the RH, KEL, FY, JK, and MNS blood group systems.

RESULTS

After additional transfusions, 21.4 percent of 653 patients produced additional antibodies, resulting in 157 new antibody specificities. At the end of the study 33.4 percent of patients had multiple antibodies. Eighty of 140 patients (57%) who formed additional antibodies did so after one transfusion episode of a median of 2 units of RBCs. Based on the antigen profile of 316 patients, 83 percent of antibodies could have been prevented by extended matching for the C, E, c, K, Fy(a), and Jk(a) antigens. Considering the current available donors in our region, 1 to 10 percent of potential donors would be available for 39 percent of patients and greater than 10 percent of potential donors for 61 percent of patients.

CONCLUSION

It has been shown that nonhematooncologic alloimmunized patients are high antibody responders, with a more than 20 times increased risk to form antibodies compared to first-time alloimmunization risk. If extended matching for C, c, E, K, Fy(a), and Jk(a) antigens in the future is considered, this group should be taken into account.

The 5q- syndrome and autoimmune phenomena: report of three cases

Myelodysplastic syndrome is a clonal hematopoietic stem cell disorder characterized by ineffective hematopoiesis, peripheral cytopenias and an additional risk to evolve to acute leukemia in up to 30% of the cases. Autoimmune manifestations as vasculitis, pyoderma gangrenosum, hemolytic anemia, immune thrombocytopenia, rheumatoid arthritis as well as positive anti-nuclear factor and rheumatoid factor have been reported in 13-30% of MDS patients. The aim of this report is to present three patients with 5q- syndrome who presented different autoimmune serological and clinical phenomena and review the literature. Patient 1 showed a focal and segmental glomerulosclerosis (FSGE) in the course of a MDS. Renal involvement in MDS as autoimmune phenomenon is rare and few reports have documented different forms of glomerular diseases in adults with MDS. Patients 2 and 3 showed a rheumatoid factor of 1/140 and the direct Coomb's test positive (3+), respectively, but without evidence of clinical autoimmune manifestation. In conclusion, patients with the 5q- syndrome experience a relative benign disease course extending over several years. We believe that careful follow-up of patients with autoimmune manifestations as here reported is important to detect any unexpected outcome.

Prophylactic antigen-matched donor blood for patients with warm autoantibodies: an algorithm for transfusion management

BACKGROUND

Patients with warm autoantibodies are at high risk for delayed hemolytic transfusion reactions due to the presence of alloantibodies. To provide blood safe for transfusion and to avoid adsorption studies in some cases, the provision of prophylactic antigen-matched donor blood where feasible for patients with warm autoantibodies is advocated.

STUDY DESIGN AND METHODS

Twenty consecutive adult patients with warm autoantibodies (January 1999 to February 2000) received chronic RBC transfusions by use of this protocol: the serology consistent with warm autoantibodies was confirmed; the alloantibodies were identified; the complete phenotype was determined (i.e., C, E, c, e, K, Jk(a), Jk(b), Fy(a), Fy(b), S, and s); and prophylactic antigen-matched (i.e., donor RBCs matched with the patient's phenotype), WBC-reduced donor RBCs were provided for transfusion. On subsequent admissions, samples were evaluated by panel studies and DATs. If the serology remained consistent with previous findings, prophylactic antigen-matched, WBC-reduced RBCs were transfused without further testing.

RESULTS

Eight of 20 (40%) patients had existing, clinically significant alloantibodies. In 12 of 20 (60%) patients, a phenotype was determined and the patients received transfusion of a total of 149 prophylactic antigen-matched RBC units (mean, 15 units per patient) precluding adsorption studies on 51 pretransfusion samples. In 8 of 20 (40%) cases (2 with alloantibodies), phenotypes were indeterminant, necessitating differential allogeneic adsorption studies on 39 samples before transfusion of 144 RBC units (mean, 18 units per patient).

CONCLUSIONS

Determining complete phenotypes should be a routine component of the serologic evaluation of patients with warm autoantibodies. Our algorithm for providing prophylactic antigen-matched RBCs to these patients when a complete phenotype can be determined provides flexibility in their transfusion management while maintaining safety and circumvents or simplifies pretransfusion adsorption studies.

The Brazilian Pediatric Myelodysplastic Cooperative Group strategies: are they relevant to improve educational approach and correct diagnosis?

Brazil is a wide country with huge contrasts. Its peculiarities can highlight environmental factors that could influence the frequencies of different cancers. The standard treatment and results achieved from several different areas of the country may not be found in others. The establishment of a national cooperative group has the potential to improve outcomes. The The Brazilian Cooperative Group on Pediatric Patients with Myelodysplastic Syndrome (BCG-MDS-PED) was first organized in January 1997 as a working group of hematologists, pediatric oncologists, pediatric-hematologists, molecular biologists and other professionals in order to study pediatric (age <18 years) MDS. Six distinct subcommittees constituted with members from several universities: cytology, histopathology, clinical, cytogenetics, molecular biology and epidemiology. The goals of the BCG-MDS-PED were: (i) to offer support for diagnosis and orientation for treatment; (ii) educational support for the colleagues all over the country and (iii) research on pathogenesis and new approaches for pediatric MDS patients. There are socio-economical differences among the five regions of the country. The BCG-MDS-PED believes that it is absolutely necessary to study the clinical, cellular, molecular and epidemiological aspects of MDS, taking in account these peculiar differences among populations and regions. Since 1997, 114 pediatric cases were referred to the BCG-MDS-PED from 21 centres. Seven Brazilian states have sent cases to the group, 31 patients were referred from universities, 73 patients from pediatric oncology units (foundations ) and 10 patients came from private clinics. Some of these patients have been followed up and/or treated by the physician who referred them to the BCG-MDS-PED for confirmation of the initial diagnosis. The majority of these physicians have required orientation on diagnostic and treatment issues, as well as to complete cytogenetic and molecular studies. From these 114 patients, 64 patients were confirmed as MDS. We believe that, the more numerous the MDS-studied cases, the more experienced will be the referee group on clinical and laboratory features on childhood MDS in Brazil.