Pure red cell aplasia

Successful Clozapine Rechallenge After Clozapine-Induced Severe Anemia: A Case Report

INTRODUCTION

Clozapine, a second-generation antipsychotic (SGA), is considered the gold standard medication to treat patients with treatment-resistant schizophrenia (TRS). Despite its efficacy, clozapine is associated with adverse effects, notably neutropenia and agranulocytosis. Other hematological adverse effects are less common. Severe anemia is a rare adverse effect seldom reported in the literature and is typically associated with pure red cell aplasia (PRCA). Nevertheless, the benefits of clozapine in managing TRS make rechallenge a reasonable option.

CASE REPORT

We present the case of a 35-year-old man with TRS, resistant to previous antipsychotics, who experienced severe anemia during clozapine treatment. An investigation for clozapine-induced anemia revealed PRCA on myelogram. After discontinuing clozapine, the patient's hemoglobin levels recovered. Subsequent treatments with olanzapine, zuclopenthixol, and aripiprazole proved ineffective, leading us to consider a clozapine rechallenge. The rechallenge, monitored for 58 days, resulted in improved psychiatric symptoms and stable hemoglobin levels. The patient remained stable during 6 months of follow-up, with no hematological changes.

DISCUSSION

PRCA is a very rare adverse effect of clozapine. The cause of drug-induced PRCA is still unknown; for clozapine, there are no studies. Rechallenge after a severe and rare adverse effect is a complex decision. This case is the first to report a successful clozapine rechallenge following severe anemia without other blood dyscrasias, emphasizing the imperative need for close monitoring during the rechallenge process. Further study is warranted to understand the predictive factors for a successful outcome in clozapine rechallenges.

Large Granular Lymphocytic Leukemia: Clinical Features, Molecular Pathogenesis, Diagnosis and Treatment

Large granular lymphocytic (LGL) leukemia is a lymphoproliferative disorder characterized by persistent clonal expansion of mature T- or natural killer cells in the blood via chronic antigenic stimulation. LGL leukemia is associated with specific immunophenotypic and molecular features, particularly STAT3 and STAT5 mutations and activation of the JAK-STAT3, Fas/Fas-L and NF-κB signaling pathways. Disease-related deaths are mainly due to recurrent infections linked to severe neutropenia. The current treatment is based on immunosuppressive therapies, which frequently produce unsatisfactory long-term responses, and for this reason, personalized approaches and targeted therapies are needed. Here, we discuss molecular pathogenesis, clinical presentation, associated autoimmune disorders, and the available treatment options, including emerging therapies.

High TOX expression on CD8+ T cells in pure red cell aplasia

Thymocyte selection-associated high-mobility group box protein (TOX) is an important molecule regulating the development and exhaustion of T lymphocytes. Our aim is to investigate the role of TOX in the immune pathogenesis of pure red cell aplasia (PRCA). TOX expression of CD8⁺ lymphocytes from the peripheral blood of patients with PRCA was detected by flow cytometry. Additionally, the expression of immune checkpoint molecules PD1 and LAG3 and cytotoxic molecules perforin and granzyme B of CD8⁺ lymphocytes was measured. The quantity of CD4⁺CD25⁺CD127^low T cells was analyzed. TOX expression on CD8⁺ T lymphocytes in PRCA patients was significantly increased (40.73 [Formula: see text] 16.03 vs. 28.38 [Formula: see text] 12.20). The expression levels of PD1 and LAG3 on CD8⁺ T lymphocytes in PCRA patients were significantly higher than those in the control group (34.18 [Formula: see text] 13.26 vs. 21.76 [Formula: see text] 9.22 and 14.17 [Formula: see text] 13.74 vs. 7.24 [Formula: see text] 5.44, respectively). The levels of perforin and granzyme in CD8⁺ T lymphocytes of PRCA patients were 48.60 [Formula: see text] 19.02 and 46.66 [Formula: see text] 25.49, respectively, which were significantly higher than those of the control group (31.46 [Formula: see text] 7.82 and 16.17 [Formula: see text] 4.84, respectively). The number of CD4⁺CD25⁺CD127^low Treg cells in PRCA patients was significantly decreased (4.30 [Formula: see text] 1.27 vs. 1.75 [Formula: see text] 1.22). In PRCA patients, CD8⁺ T cells were activated and exhibited overexpression of TOX, PD1, LAG3, perforin, and granzyme B, while regulatory T cells decreased. These findings suggest that T cell abnormality plays a critical role in the pathogenesis of PRCA.

Treating Parvovirus Triggered Refractory Hemolytic Anemia with Rituximab in Renal Transplant Recipients - A Report of Two Cases

Parvovirus B19 is a small (26 nm), nonenveloped, single-stranded DNA (5.6-kb) virus. The only known host for parvovirus B19 is humans. Parvovirus B19 is directly cytotoxic to erythroid precursor cells of the colony- and burst-forming units. Human parvovirus B19 is the etiologic agent of erythema infectiosum and chronic pure red cell aplasia in immunocompromised individuals. Acute parvovirus B19 infection should be suspected in immunocompromised patients, who present with reticulocytopenic hemolytic anemia and thrombocytopenia. Intravenous immunoglobulin (IVIg) is the standard treatment for parvovirus-induced cytopenias. We report two cases of postrenal transplant who presented with reticulocytopenic anemia and were found to have parvovirus infection. They did not respond to conventional treatment with intravenous gamma globulin. Both patients were treated with rituximab with which they had improvement in clinical and hematological parameters. There was no previous documentation of using rituximab in the treatment of parvovirus-triggered autoimmune hemolytic anemia postrenal transplant patients. This article illustrates how rituximab will be helpful in this setting, of course, it is a new thought but requires further studies and validation.

Case Report: Pulmonary Tuberculosis Accompanied by Pure Red Cell Aplasia and Autoimmune Hemolytic Anemia

Tuberculosis is one of the most common infections worldwide. It has been associated with some hematologic disorders; however, pure red cell aplasia or autoimmune hemolytic anemia is rarely reported. We describe the case of a 68-year-old woman with pulmonary tuberculosis accompanied by pure red cell aplasia and autoimmune hemolytic anemia. These hematologic disorders were improved by treatment of pulmonary tuberculosis. This case suggests that physicians should consider the possibility of tuberculosis as a cause of pure red cell aplasia.

T cell clonal expansion and STAT3 mutations: a characteristic feature of acquired chronic T cell-mediated pure red cell aplasia

Acquired chronic pure red cell aplasia (PRCA) develops idiopathically or in association with other medical conditions, including T cell large granular lymphocytic leukemia (T-LGLL) and thymoma. T cell dysregulation is considered a cardinal pathogenesis of PRCA, but genetic-phenotypic associations in T cell abnormalities are largely unclear. We evaluated an extended cohort of 90 patients with acquired PRCA, including 26 with idiopathic, 36 with T-LGLL-associated and 15 with thymoma-associated PRCA, for their T cell immuno-phenotypes, clonalities and STAT3 mutations. TCR repertoire skewing of CD8⁺ T cells was detected in 37.5% of idiopathic, 66.7% of T-LGLL-associated and 25% of thymoma-associated PRCA patients, and restriction to Vβ1 was most prominent (41%). Clonalities of TCRβ or γ chain and STAT3 mutational status were statistically associated (P = 0.0398), and they were detected in all three subtypes. The overall response rate to cyclosporin A was 73.9%, without significant difference by subtypes nor STAT3 mutational status. The T cell dysregulations, such as TCR repertoire skewing with predominant Vβ1 usage, clonality and STAT3 mutations, were frequently found across the subtypes, and the close associations between them suggest that these T cell derangements reflect a common pathophysiological mechanism among these PRCA subtypes.

Persistent Large Granular Lymphocyte Clonal Expansions: “The Root of Many Evils”—And of Some Goodness

Simple Summary

Large granular lymphocyte leukemia (LGLL) is a chronic disorder of either mature T or NK lymphocytes. As clonal expansions of the immune system cells, difficulties in the distinction between a true neoplasia and a physiological reactive process have been common since its description. We review here the different conditions associated with persistent clonal LGL expansions and discuss their potential origin and whether they can modulate the clinical features.

Abstract

Large granular lymphocyte leukemia (LGLL) is a chronic disease of either mature phenotype cytotoxic CD3+ T lymphocytes or CD3- NK cells. LGLL diagnosis is hampered by the fact that reactive persistent clonal LGL expansions may fulfill the current criteria for LGLL diagnoses. In addition to the presence of characteristic clinical and hematological signs such as anemia or neutropenia, LGLL/LGL clonal expansions have been associated with an array of conditions/disorders. We review here the presence of these persistent clonal expansions in autoimmune, hematological disorders and solid neoplasms and after hematopoietic stem cell transplantation. These associations are a unique translational research framework to discern whether these persistently expanded LGL clones are causes or consequences of the concomitant clinical settings and, more importantly, when they should be targeted.

Pure red cell aplasia secondary to rheumatoid arthritis: a case report

BACKGROUND

Rheumatoid arthritis is a common autoimmune disease with many extra-articular manifestations. Pure red cell aplasia is a rare manifestation of rheumatoid arthritis and is sparsely documented in the literature, with a variable clinical outcome following immunosuppressive therapy.

CASE PRESENTATION

A 63-year-old Sinhalese female presented with transfusion-dependent anemia associated with deforming inflammatory arthritis. She also had leukopenia, right subclavian venous thrombosis, and generalized lymphadenopathy. The diagnosis of rheumatoid arthritis following initial clinical workup and additional blood and bone marrow investigations revealed pure red cell aplasia as a secondary manifestation of rheumatoid arthritis after excluding other secondary causes, such as infections, thymoma, thrombophilic conditions, and hematological malignancy. She responded well to oral prednisolone, cyclosporine A, and hydroxychloroquine, and she attained complete recovery in 2 months.

CONCLUSION

Pure red cell aplasia is a disabling illness that may lead to transfusion-dependent anemia, which may occur due to rare extrapulmonary manifestation of rheumatoid arthritis. The diagnosis of pure red cell aplasia secondary to rheumatoid arthritis may be challenging where hematological investigations, including bone marrow biopsy, will aid in the diagnosis, and early diagnosis and treatment will bring about a better outcome.

True thymic hyperplasia causing pure red cell aplasia: a case report

Pure red cell aplasia caused by true thymic hyperplasia is extremely rare. We report the case of a 25-year-old female diagnosed with pure red cell aplasia. Following a thymectomy confirming true thymic hyperplasia and corticosteroid therapy, complete response was achieved. Patients diagnosed with pure red cell aplasia should be investigated with a computerized tomographic scan to assess for thymic pathology and if present, this should be resected. Follow-up is essential to monitor for recurrence.

Pure Red Cell Aplasia with Del(20q) Sensitive for Immunosuppressive Treatment

Pure red cell aplasia (PRCA) is a rare syndrome that only affects the erythroid lineage. It is defined by a normocytic, normochromic anemia with a marked reticulocytopenia and severe reduction or absence of erythroid precursors in the bone marrow. Treatment of primary, idiopathic PRCA is immunosuppressive therapy. Although it is rare, isolated cytogenetic abnormalities can be seen in PRCA, and abnormal karyotype is associated with poor response to immunosuppressive therapy and poor prognosis. We describe a 77-year-old male with primary, idiopathic PRCA and a deletion of chromosome 20q, del(20q), in the bone marrow cells. He was successfully treated with immunosuppressive therapy and became transfusion-independent. The same cytogenetic abnormality has also been described in a few other reports; taken together, these observations suggest that del(20q) may represent a recurrent cytogenetic abnormality in PRCA. Our case report clearly illustrates that even patients with primary PRCA and an abnormal karyotype can respond to immunosuppression and become transfusion-independent.

Induced complete remission faster in adult patients with acquired pure red cell aplasia by combining cyclosporine A with corticosteroids

To evaluate whether the adult patients with acquired pure red cell aplasia (PRCA) could benefit more from cyclosporine A (CsA) combined with corticosteroids (CS) than CsA or CS alone.Seventy-three patients were evaluated in 2 institutions (6 patients lost to follow-up).The induction therapy included CsA (n = 21), CS (n = 21), or CsA combined with CS (n = 31), and remission was achieved in 16/21 (76.2%), 10/21 (47.6%), and 21/31 (71.0%) patients, respectively. Higher complete remission (CR) rate was achieved in CsA combined with CS group than in CS group (61.3% vs 19.0%, P = .003). Patients achieved CR faster in CsA combined with CS group than in CS group or CsA group (median time, 1 month vs 2 month vs 3 month, P = .010). By multivariate analysis, CsA combined with CS therapy and primary PRCA were the influence factors for CR rate. Twenty-seven patients relapsed due to discontinuation or tapering therapy, and 19 patients regained response by increasing the dose of original regimens or changing to other immunosuppressive therapy. Complete remission to induction therapy was a correlative factor for death (P = .035).CsA combined with CS produced faster and higher CR rate in treating adult patients with PRCA than did CsA or CS alone.

[Pure red cell aplasia of the bone marrow in combination with thymoma. A literature review and own data]

Eight patients were observed with a rare combination of thymoma and pure red cell aplasia of bone marrow (PRCA), of which seven women were between 44 to 68 years old. The diagnosis of PRCA was established before the detection of thymoma in 1 patient, simultaneously in 3, after - in 4. Seven patients underwent timomectomy. The weight of removed thymomas was from 200 to 780 grams. Morphological type A thymoma variant (spindle cell) was installed in 2 patients, type B1 - in 2, type B2 - in 2, type B3 - in 2. Complete remissions were obtained using cyclophosphamide and cyclosporin in 5 patients, lasting from 6 months to 7 years. The results of immunological studies with the identification of non - hemolytic antibodies to the proteolytic antigen (Pr1d) on the erythrocyte membrane in 4 patients are presented. Of these, two studied patients simultaneously detected antibodies to the Pr1d antigen and the interspecific antigen of mammalian erythroblasts (IAME). It is shown that the lifespan of red blood cells are not changed. The direct Coombs test was negative in 5 patients, but with the help of aggregate hemaglutination test and enzyme immunoassay, antibodies were detected on the surface of erythrocytes. The pathogenesis of this combination of diseases remains unclear and needs to be elucidated.

Isoniazid-induced pure red cell aplasia

The pure red cell aplasia (PRCA) is an uncommon side effect of isoniazid. We describe a 28-year-old man who developed a severe anaemia caused by PRCA. The patient received antituberculous therapy including isoniazid for his pulmonary tuberculosis. On discontinuation of isoniazid, the anaemia recovered promptly. PRCA should be considered in case of unexplained anaemia during isoniazid treatment.

Identification of mutations in patients with acquired pure red cell aplasia

Idiopathic acquired pure red cell aplasia (PRCA) is a rare, autoimmune-related disease. This study aimed to describe the previously unidentified DNA alterations associated with PRCA. Here, next generation sequencing using a panel containing 295 critical genes was applied to detect potentially pathogenic mutations in four patients with PRCA. A total of 529 mutations were identified and further classified into three categories, namely, uncertain (n = 25), likely benign (n = 20) and benign (n = 484) mutations, based on the American College of Medical Genetics and Genomics (ACMG) 2015 guidelines and ClinVar database. The spatial proximity between two loci of the uncertain or benign mutations was evaluated using Hi-C datasets of KBM7 and K562 cell lines, respectively. Significant spatial proximity was observed in uncertain mutation pairs compared with benign mutation pairs. In addition, 17 variants were eventually identified after excluding those with mutant frequencies >0.001, including 7 newly identified variants. FANCF and LRP1B mutations existed twice in patients. FANCF and LRP1B mutations were likely to affect protein stability based on prediction analysis. Taken together, our data may provide valuable information about PRCA. FANCF and LRP1B mutations may be associated with acquired PRCA.

An unusual case of anemia in a cardiac transplant recipient

Anemia is a well-described comorbidity in patients with heart failure and has been associated with decreased survival rates after heart transplant. The causes of anemia are broad, and identification of the underlying etiology is critical for management. Herein, we report an unusual case of severe anemia complicating cardiac transplantation.

Refractory Pure Red Cell Aplasia Manifesting as Deficiency of Adenosine Deaminase 2

Primary progress has been made in the last 2 years, particularly in finding novel disease-causing genes for a number of autoinflammatory diseases and primary immunodeficiencies. Whole-exome sequencing has dramatically increased the pace at which causative genes are being discovered. CECR1 (Cat eye syndrome chromosome region, candidate 1) gene encodes adenosine deaminase 2 (ADA2) protein. Patients who carry CECR1 mutation(s) suffer from deficiency of ADA2 (DADA2). Here, we describe a patient with pure red cell aplasia discovered to have DADA2. We also review the literature on DADA2. This report will help raise awareness of physicians for this complex disease.

Anemia in malignancies: pathogenetic and diagnostic considerations

OBJECTIVES

The aim of this paper is to review the pathogenesis and diagnostic approaches to anemia in cancer patients.

METHODS

PubMed was queried for various combinations of anemia and cancer-related terms using appropriate filters for articles and practice guidelines published in the last 5 years. Specific searches were conducted for individual pathogenetic mechanisms and malignancies of specific anatomic sites.

RESULTS

Anemia is the commonest hematological manifestation of cancer, afflicting 40-64% of patients treated for malignancies. Pathophysiologically, cancer-related anemia can be classified into four broad but overlapping categories: hypoproliferative anemia including the common anemia of inflammation/chronic disease, hemolytic anemia, miscellaneous etiologies, and uncertain etiologies. Anemia incidence increases with the administration of chemotherapy/radiotherapy. It reduces the quality of life and shortens survival in cancer patients. A positive correlation is observed between anemia and tumor hypoxia. Experimentally, hypoxemia enhances tumor growth and resistance to therapy by stimulating angiogenesis, acquisition of genomic mutations, and increasing resistance to apoptosis as well as to the killing effects of chemo/radiotherapy-generated free radicals.

DISCUSSION

Diagnostic approaches to the anemic cancer patient begin with a detailed clinical history and physical examination. Peripheral blood morphology and reticulocyte count are also helpful. Patients with unexplained anemia are evaluated by standard approaches also used in patients of similar age without malignancy. Serum iron profile and bone marrow examination are often required in difficult cases. This review focuses on major aspects of the pathogenesis of the individual entities. Diagnostic approaches and uncommon causes including hemophagocytic lymphohistiocytosis, acquired hemoglobinopathies, and myelodysplasia are also discussed.

CD8(+) T cell activation by murine erythroblasts infected with malaria parasites

Recent studies show that some human malaria parasite species Plasmodium falciparum and P.vivax parasitize erythroblasts; however, the biological and clinical significance of this is unclear. To investigate further, we generated a rodent malaria parasite (P. yoelii 17XNL) expressing GFP-ovalbumin (OVA). Its infectivity to erythroblasts was confirmed, and parasitized erythroblasts were capable of initiating malaria infections. Experiments showed that MHC class I molecules were highly expressed on parasitized erythroblasts. As CD8⁺ T cells recognize MHC class I and peptide complexes on target cells, and are involved in protection or pathology against malaria, we examined whether erythroblasts are targeted by CD8⁺ T cells. Purified non-parasitized erythroblasts pulsed with OVA peptides were recognized by OVA-specific CD8⁺ T cells. Crucially, parasitized erythroblasts isolated from GFP-OVA-, but not GFP- infected-mice, activated OT-I CD8⁺ T cells, indicating that CD8⁺ T cells recognize parasitized erythroblasts in an antigen-specific manner.

Diamond-Blackfan anemia: Clinical features and treatment results in 4 cases

Diamond-Blackfan anemia is a rare hematological disease characterized by selective marrow erythroid hypoplasia. We present the clinical and hematological profile and results of treatment in four children. The median age at presentation was 14 months with a median age of onset of pallor at 7.5 months. Mean Hb at presentation was 2.9 g/dl. All children were started on prednisolone with response in one child. One child was switched to dexamethasone and responded transiently relapsing in 4 months but responded to further dexamethasone. Two children required cyclosporin for 3 and 8 weeks for response. With median follow-up of 59 months, all four children continue in complete hematological remission with no further relapses.

Antiepoetin antibody-related pure red cell aplasia: successful remission with cessation of recombinant erythropoietin alone

An elderly patient with pure red cell aplasia (PRCA) with antierythropoietin (anti-EPO) antibodies is described. PRCA due to alloimmunization is a rare and severe complication of recombinant human erythropoietin (rHu-EPO) therapy. Most reported patients with PRCA were cured primarily by immunosuppressive drug therapy. The patient in this case, however, did not want to receive any immunosuppressive drugs. Therefore, rHu-EPO injection was simply discontinued, the severe anemia gradually improved, and the hemoglobin approached normal range. This case is very rare and significant in that there have been few such elderly patients with rHu-EPO-induced PRCA in whom PRCA remission was achieved, with decreasing antibody titers, after cessation of rHu-EPO alone. Further cases are needed to assess how PRCA should be treated in patients with anti-EPO antibodies.

Diagnosis and management of acquired pure red cell aplasia

Pure red cell aplasia is a syndrome characterized by a severe normocytic anemia, reticulocytopenia, and absence of erythroblasts from an otherwise normal bone marrow. Although the causes and natural course of this syndrome are variable and although the anemia in some patients can be managed by treatment of an underlying inflammatory or neoplastic disease, the pathogenesis of a large number of cases is autoimmune, including those associated with thymoma, and are best managed with immunosuppressive therapy.

Acute viral infections in patients with systemic lupus erythematosus: description of 23 cases and review of the literature

Few studies have evaluated the impact of viral infections on the daily management of patients with systemic lupus erythematosus (SLE). We analyzed the etiology and clinical features of acute viral infections arising in patients with SLE and their influence on the diagnosis, prognosis, and treatment of SLE. Cases occurring within the last 5 years were selected from the databases of 3 large teaching hospitals. Acute viral infections were confirmed by the identification of specific antiviral IgM antibodies and subsequent seroconversion with detection of specific IgG antibodies. In autopsy studies, macroscopic findings suggestive of viral infection were confirmed by direct identification of the virus or viruses in tissue samples. We performed a MEDLINE search for additional cases reported between January 1985 and March 2008. We included 88 cases (23 from our clinics and 65 from the literature review) of acute viral infections in patients with SLE. Twenty-five patients were diagnosed with new-onset SLE (fulfillment of the 1997 SLE criteria) associated with infection by human parvovirus B19 (n = 15), cytomegalovirus (CMV; n = 6), Epstein-Barr virus (EBV; n = 3), and hepatitis A virus (n = 1). The remaining 63 cases of acute viral infections arose in patients already diagnosed with SLE: in 18 patients, symptoms related to infection mimicked a lupus flare, 36 patients, including 1 patient from the former group who presented with both conditions, presented organ-specific viral infections (mainly pneumonitis, colitis, retinitis, and hepatitis), and 10 patients presented a severe, multiorgan process similar to that described in catastrophic antiphospholipid syndrome-the final diagnosis was hemophagocytic syndrome in 5 cases and disseminated viral infection in 5. Twelve patients died due to infection caused by CMV (n = 5), herpes simplex virus (n = 4), EBV (n = 2), and varicella zoster virus (n = 1). Autopsies were performed in 9 patients and disclosed disseminated herpetic infection in 6 patients (caused by herpes simplex in 4 cases, varicella in 1, and CMV in 1) and hemophagocytic syndrome in 3. A higher frequency of renal failure (54% vs. 19%, p = 0.024), antiphospholipid syndrome (33% vs. 6%, p = 0.023), treatment with cyclophosphamide (82% vs. 37%, p = 0.008), and multisystemic involvement at presentation (58% vs. 8%, p < 0.001); and a lower frequency of antiviral therapy (18% vs. 76%, p < 0.001) were found in patients who died, compared with survivors. The most common viral infections in patients with SLE are parvovirus B19 (predominantly mimicking SLE presentation) and CMV (predominantly presenting in severely immunosuppressed patients). CMV infection may mimic a lupus flare or present with specific organ involvement such as gastrointestinal bleeding or pulmonary infiltrates. Other herpesviruses are common in immunosuppressed SLE patients and may produce a wide range of manifestations. Physicians should examine the pharynx, eyes, skin, and genitalia and should conduct serologic and molecular studies to improve early detection of viral infection in patients with SLE.

Pure red-cell aplasia secondary to pregnancy, characterization of a syndrome

The aim of this study was to characterize the syndrome of pure red-cell aplasia (PRCA) secondary to pregnancy. All published cases of PRCA induced by pregnancy were reviewed. Additionally, we reported a patient who developed PRCA on three occasions; two were triggered by pregnancy and one after medroxyprogesterone administration. Ten patients with 13 pregnancy-induced PRCA episodes were reported. The PRCA occurred at any gestational age. All patients received blood transfusions, and six of them were treated corticosteroids. The PRCA resolved in all subjects postpartum. Five women had subsequent pregnancies; three were complicated by PRCA, one was normal, and one had spontaneous abortion without PRCA. One subject developed a PRCA after long-term exposure to medroxyprogesterone. Infant blood values were normal in the nine reported cases. Pregnancy-induced PRCA is a self-limited syndrome with a high risk for relapse during subsequent pregnancies. It can be managed by blood transfusions. Progestins might cause PRCA in these women.

A case of systemic lupus erythematosus complicated by pure red cell aplasia and idiopathic portal hypertension after thymectomy

We describe a 49-year-old woman who presented in 2002 with pure red cell aplasia (PRCA), systemic lupus erythematosus (SLE), and idiopathic portal hypertension (IPH) that developed following a thymectomy. She underwent a thymectomy at 40 years of age to treat myasthenia gravis. PRCA developed 3 years after the thymectomy and she was successfully treated with cyclosporin. Systemic lupus erythematosus and IPH were diagnosed 6 years later. We conclude that immunological dysfunction resulting from the thymectomy contributed significantly to the subsequent development of PRCA, SLE, and IPH in this patient. This is the first report to describe this extremely rare occurrence.

[Appearance of central nervous system lupus during corticosteroid therapy and warfarinization in a patient with pure red cell aplasia and antiphospholipid syndrome]

A 48-year-old woman presented to our hospital with epigastralgia and erythema on the left dorsalis pedis. Her medical history included deep venous thrombosis three months prior to admission to our hospital. Upon admission it was determined that she had severe anemia (hemoglobin level 4.6 g/dl). Bone marrow analysis indicated a markedly decreased number of erythroid progenitor cells. A skin biopsy specimen of the erythema revealed microthrombus. Anticardiolipin-beta2GPI antibody and lupus anticoagulant were positive. The patient was diagnosed with pure red cell aplasia (PRCA) and antiphospholipid syndrome (APS). After steroid pulse therapy and warfarinization, her anemia and purpura improved. Three months later she developed depression with positive anti-ribosomal P protein antibody that was indicative of central nervous system lupus. Although her psychometric condition did not respond to steroid pulse therapy, improvement was seen after she received three courses of cyclophosphamide pulse therapy. We report a rare case of CNS lupus that developed during corticosteroid therapy and warfarinization in a patient with PRCA and APS.

Large Granular Lymphocyte Leukemia

Clonal disorders of large granular lymphocytes (LGLs) represent a spectrum of biologically distinct lymphoproliferative diseases originating either from mature T cells (CD3+) or natural killer (NK) cells (CD3-). Both subtypes, T-cell and NK-cell LGL leukemia, can manifest as indolent or aggressive disorders. The majority of patients with T-cell LGL leukemia have a clinically indolent course with a median survival time >10 years. Immunosuppressive therapy with low-dose methotrexate, cyclophosphamide, or cyclosporine A can control symptoms and cytopenias in more than 50% of patients, but this approach is not curative. Several cases of an aggressive variant (CD3+ CD56+) of T-cell LGL leukemia with a poor prognosis have also been reported. Aggressive NK-cell LGL leukemia is usually a rapidly progressive disorder associated with Epstein-Barr virus (EBV), with a higher prevalence in Asia and South America. This disease is usually refractory to conventional chemotherapy, with a median survival time of 2 months. Chronic NK-cell leukemia/lymphocytosis is a rare EBV-negative disorder with an indolent clinical course. The malignant origin of this subtype is uncertain because clonality is difficult to determine in LGLs of NK-cell origin.

The influence of blood group differences in allogeneic hematopoietic peripheral blood progenitor cell transplantation

BACKGROUND

Severe immunohematologic complications after ABO-mismatched allogeneic blood peripheral blood progenitor cell (PBPC) transplantation (PBPCT), including pure red cell aplasia and immune hemolysis, have been described. Although several studies have addressed this issue, the clinical influence of blood group differences on transfusion requirements and survival is still discussed controversially, especially in the case of PBPCT.

STUDY DESIGN AND METHODS

This single-center study is based on 143 patients receiving PBPCT after standard or reduced-intensity conditioning. The influence of blood group differences in the ABO, Rh, and Kell systems on red blood cell, platelet, and plasma transfusion requirements; length of hospitalization in transplantation unit; survival; and occurrence of graft-versus-host disease was investigated. Additionally, the influence of the conditioning regimen and irregular antibodies on the measures mentioned above was analyzed.

RESULTS

Multivariate analysis demonstrated that minor and bidirectional ABO mismatch (p = 0.028) and Rh difference (p = 0.020) independently led to poorer survival. The Kell difference did not show significant influences on the measures mentioned above. A clinically relevant influence of blood group differences on transfusion requirements could not be demonstrated. Irregular antibodies also did not show significant influences.

CONCLUSION

These findings indicate an influence of blood group differences in PBPCT on survival and must be studied in further detail.

Recommendations on haematological criteria for the diagnosis of epoetin-induced pure red cell aplasia

Pure red cell aplasia (PRCA) is a rare condition characterised by an arrest in red blood cell production, which may be congenital or acquired. Recombinant human erythropoietin (epoetin) was introduced in 1989 for the treatment of anaemia of chronic kidney disease patients and has maintained an excellent therapeutic and safety record while treating hundreds of thousands of patients. A very rare, but serious adverse event associated with epoetin administration is a condition in which patients develop neutralising anti-erythropoietin antibodies and, consequently, PRCA. This condition is referred to as epoetin-induced PRCA (epo-PRCA). Since it is a rare condition, many haematologists and nephrologists around the world see the condition infrequently and may be uncertain about the diagnosis. For this reason, an ad hoc international working group of expert haematologists and nephrologists met together to derive new recommendations for the haematological diagnosis of epo-PRCA. These recommendations, which represent the consensus opinions of the working group, address haematological approaches to monitor and investigate suspected epo-PRCA and should help physicians differentiate between PRCA and other bone marrow diseases, as well as, between PRCA and epo-PRCA.

Successful high-titer immunoglobulin therapy for persistent parvovirus B19 infection in a lymphoma patient treated with rituximab-combined chemotherapy

A 40-year-old female diagnosed with follicular lymphoma was treated with rituximab-combined chemotherapy. Although she achieved complete remission, she developed progressive anemia and reticulocytopenia. Bone marrow examination revealed features of pure red cell aplasia and hemophagocytosis. In addition, the appearance of large pronormoblasts suggested that she was infected with parvovirus B19. Excess viral DNA in her bone marrow confirmed that her illness was caused by persistent parvovirus B19 infection. Serum immunoglobulin levels decreased beyond the lower normal limit, which indicated that her humoral immunity was impaired after rituximab-combined chemotherapy. Although she had been infected with parvovirus B19, she was re-infected and failed to control the viral expansion. High-titer immunoglobulin against parvovirus B19 was intravenously administrated and resulted in remarkable reticulocytosis and improvement of anemia. High-titer immunoglobulin, which contained a sufficient amount of neutralizing antibodies against parvovirus B19, likely inactivated most viruses in vivo. We successfully eradicated the virus after 2 courses of high-dose therapy at 0.5 g/kg/day every week followed by 8 courses of maintenance therapy at 0.1 g/kg/day every other week. It is important to consider that parvovirus B19 infection is a possible cause of progressive anemia in B-cell lymphoma patients treated with rituximab-combined chemotherapy. We propose that the use of high-titer immunoglobulin against parvovirus B19 may enable such immunocompromised patients to eradicate the virus before sufficient immune system reconstruction.

A sustained response to low dose interferon-α in a case of refractory pure red cell aplasia

Acquired pure red cell aplasia (PRCA) may be the result of a cellular or humoral autoimmune process. One proposed mechanism is the destruction of erythroid progenitors by self-reactive, cytotoxic T cells or natural killer (NK) cells. These cells normally express MHC class I receptors (KIR) which inhibit cytotoxicity when the target cell expresses the HLA class I antigen(s) they bind. Therefore, loss of these antigens on maturing erythroid progenitors may render them susceptible to destruction by the pathogenic cells. Interferon-alpha (INF-alpha) increases HLA class I expression on hematopoietic precursor cells. Therefore, we initiated a trial of INF-alpha in a patient with refractory PRCA. Following treatment, he developed transfusion independence, and a sustained normal hematocrit. Analysis of bone marrow erythroid cells revealed an increase in expression of HLA class I molecules. INF-alpha should be used in a controlled trial in patients with PRCA to determine its activity and mechanism of action.

T-cell large granular lymphocyte leukemia and related disorders

T-cell large granular lymphocyte (LGL) leukemia is a clonal proliferation of cytotoxic T cells, which causes neutropenia, anemia, and/or thrombocytopenia. This condition is often associated with autoimmune disorders, especially rheumatoid arthritis, and other lymphoproliferative disorders. The diagnosis is suggested by flow cytometry demonstrating an expansion of CD8(+)CD57(+) T cells and is confirmed by T-cell receptor gene rearrangement studies. Mounting evidence suggests that LGL leukemia is a disorder of dysregulation of apoptosis through abnormalities in the Fas/Fas ligand pathway. In most patients, this is an indolent disorder, and significant improvement of cytopenias can be achieved with immunosuppressive agents such as steroids, methotrexate, cyclophosphamide, and cyclosporin A. This review provides a concise, up-to-date summary of LGL leukemia and the related, more aggressive, malignancies of cytotoxic T cells and natural killer cells.

Myelodysplastic syndrome with erythroid aplasia following pure red cell aplasia

Myelodysplastic syndrome (MDS) with erythroid aplasia is a very rare disorder that has not been clearly defined. We experienced a case of pure red cell aplasia (PRCA), which evolved to MDS with erythroid aplasia. A 59-year-old male with transfusion-dependent PRCA was referred to our hospital for an evaluation of newly developed thrombocytopenia. Two years ago, PRCA was diagnosed by the laboratory findings and a bone marrow examination, which showed no evidence of any myelodysplastic features and thymoma. Upon admission, the bone marrow findings showed marked hypercellularity. with numerous dysplastic features in the three lineages including erythroid hypoplasia. These findings were compatible with a diagnosis of MDS with red cell aplasia. It is very interesting that the PRCA evolved to MDS with red cell aplasia, which strongly suggests an autoimmune mechanism for the development of MDS.

Pure red cell aplasia associated with expansion of CD3+ CD8+ granular lymphocytes expressing cytotoxicity against HLA-E+ cells

T-cell granular lymphocyte-proliferative disorder (T-GLPD) is characterized by the proliferation of cytotoxic T lymphocytes, and is often associated with pure red cell aplasia (PRCA). The mechanism involved in the development of PRCA in T-GLPD is unknown. Peripheral blood mononuclear cells were isolated from 20 patients with T-GLPD. Ten patients had associated PRCA. Granular lymphocytes (GLs) of T-GLPD are positive for CD94, but not NKG2A. To clarify the functional role of CD94 in T-GLPD, we performed a cytotoxicity assay against the trophoblast cell line, BeWo, which is known to express human leucocyte antigen (HLA)-E, a natural ligand of CD94, and is deficient in other HLA class I and class II antigens. GLs isolated from T-GLPD with PRCA patients killed BeWo cells more significantly than GLs from T-GLPD without PRCA patients. Furthermore, GLs from T-GLPD with PRCA were significantly stimulated by a monoclonal antibody against CD94, whereas those of T-GLPD without PRCA were not. Taken together, HLA-E, a ligand of CD94, was suggested to stimulate CD94+ cells to kill HLA-E+ cells in T-GLPD with PRCA. GLs of T-GLPD with PRCA have a potential positive activity against HLA-E+ cells, whereas GLs from T-GLPD without PRCA do not. CD94 may play a key role in the pathogenesis of PRCA in T-GLPD.