Case Of Pure Red Cell Aplasia Research Articles

Pure red cell aplasia among ABO mismatched hematopoietic stem cell transplant recipients: a 13-years retrospective study and literature review.

Pure red cell aplasia (PRCA) is a possible complication after allogeneic hematopoietic stem cell transplantation (HSCT) with major ABO incompatibility. Patients experience delayed engraftment of the erythroid series, with prolonged transfusion-dependent anemia and iron overload. We performed a revision of the most recent literature about post-HSCT PRCA treatment procedures. Moreover, we conducted a retrospective study, over the last 13-years, which included all consecutive major ABO mismatched HSCT performed in our unit, with the aim to assess PRCA incidence, risk factors, and response to different treatments. Overall, 194 patients received a major ABO mismatched transplant from 2010 to 2022. For each patient, data about demographic and transplant characteristics, engraftment, blood transfusion, and possible treatment received were collected. The literature review returned 23 eligible papers on PRCA treatment, with high success rate using plasma-exchange (PEX) and immunoadsorption procedures, daratumumab, and eltrombopag. Our study identified a total of 24 cases of PRCA. Among risk factors for PRCA development, we have found older recipient age (p=0.01), high pre-HSCT IgG and IgM IHA titer (p<0.0001), major rather than bidirectional ABO incompatibility (p=0.02), low T CD8 lymphocyte count in the graft (p=0.006), relative donor (p=0.02) and bone marrow as stem cell source (p=0.002). However, multivariate analysis confirmed only pre-HSCT IgG IHA titer as the unique risk factor for PRCA occurrence. The optimal cut-off value of pre-HSCT IgG IHA for PRCA development, resulted to be 1/64, with a 100% sensitivity and 68.8% specificity (p<0.0001). All patients with PRCA had received rhEPO and transfusion support and 20 patients received additional treatments like PEX, rituximab, and more recently daratumumab. Comprehensively, PEX and rituximab obtained a response in half of the cases, at a variable time, while the few cases of patients we treated with daratumumab suggest promising results. The overall response rate in our cohort was 75%, with significantly better survival (94.4% vs. 16.7%) and lower transplant-related mortality (6.3% vs. 80%) for PRCA responders. Standardized guidelines on when and how to treat PRCA are necessary because the current treatment is controversial among centers.

#1572 Recurrent parvovirus B19 infection-associated pure red cell aplasia in kidney transplantation

Abstract Background and Aims Anemia is frequent in kidney transplant (KT) recipients, with multiple potential causes. Parvovirus B19 (PVB19) infection-associated pure red cell aplasia (PRCA) becomes an important diagnosis in KT recipients experiencing persistent anemia, in whom other etiologies have been excluded. PVB19-associated PRCA is described in up to 27% of KT recipients with anemia and recurrent disease in up to 33% of cases. The authors describe a case of a recurrent PVB19-associated PRCA in a KT recipient. Method - Results A 42-year-old male with chronic kidney disease of unknown etiology underwent KT from a deceased donor after circulatory death in January 2021. He received induction immunosuppression (IS) with thymoglobulin and maintenance IS with prednisolone, tacrolimus, and mycophenolate mofetil (MMF). Three months after KT, the patient complained of progressive asthenia, and normocytic normochromic (NN) anemia was detected. A thorough investigation revealed normal leucocyte and platelet counts, low reticulocyte count, and no signs of bacterial infection, iron deficiency, or hemolysis; thyroid function, erythropoietin, folate, and vitamin B12 levels were normal, direct Coombs test was negative and no monoclonal spike was detected on protein electrophoresis. Endoscopic studies and cervico-thoraco-abdomino-pelvic computer tomography were unremarkable. Serum PCR of PVB19 was positive and confirmed the diagnosis of PVB19-associated PRCA. MMF was discontinued but anemia continued aggravating (nadir hemoglobin [Hg] level of 6.6 g/dL) with a sustained PVB19 load. He was admitted to the hospital, received blood transfusions, and was started on intravenous immunoglobulin (IVIG) 2 g/kg. A bone marrow aspirate was performed and was compatible with recovery after erythroid aplasia. The patient was discharged with Hg 8 g/dL and reduced PVB19 load. Although MMF remained suspended, and close monitoring of Hg and PVB19 load was performed, four months later he developed recurrent PVB19-associated PRCA, which motivated another hospital admission for IVIG with excellent response. In addition, he presented kidney dysfunction, and a kidney biopsy revealed borderline acute T-cell mediated rejection. In this setting, IS was altered to TRANSFORM SCHEEME. Four months later, he presented a second recurrence of PVB19-associated PRCA, requiring new hospitalization and treatment with IVIG. Considering the recurrent PVB19-associated PRCA, in a patient with chronic allograft dysfunction, high immunologic risk, and the foscarnet's probable nephrotoxicity, preventive therapy with IVIG (0.4 mg/kg) every 4 weeks was started. After 7 months of preventive IVIG infusion, no relapse was identified, the Hg is 11.5 g/dL (and increasing, without erythropoiesis stimulants) and the PVB19 load remains low. Conclusion PVB19-associated PRCA is characterized by persistent NN anemia with low reticulocyte counts, which is unresponsive to erythropoietin. One significant risk factor is induction IS, particularly thymoglobulin. In the setting of solid organ transplants, the absence of PVB19 antibodies does not exclude this diagnosis and viral detection should be performed. The initial therapeutic approach involves reducing IS. However, the risk of allograft rejection must be acknowledged. If this approach proves insufficient, IVIG treatment is usually successful. In our patient, considering the facts that allograft rejection limits the reduction of IS, the need for blood transfusions, and the inherent immunization, in a young patient that will possibly require a second KT, the undesirable nephrotoxicity of foscarnet, the successful response to IVIG, and patient's quality of life, chronic IVIG therapy was thought to be the best choice and proved efficacious in preventing relapses. Despite the absence of precise guidelines for chronic PVB19 infection management, maintenance therapy with prolonged IVIG infusions may be a therapeutic option for recurrent PRCA, but more studies are necessary to define the appropriate duration of treatment.

Successful treatment pure red cell aplasia after ABO major mismatched allogeneic hematopoietic stem cell transplantation with avatrombopag and low dose rituximab.

Pure red cell aplasia (PRCA) following allogeneic hematopoietic stem cell transplantation (allo-HSCT) with ABO major incompatibility is characterized by transfusion dependent anemia. No standard treatment existed for PRCA following allo-HSCT yet. We conducted a retrospective study, and reported our experience with the use of avatrombopag and lower dose rituximab to treat five patients with PRCA subsequent to major ABO-incompatible allo-HSCT. Five cases of PRCA were identified from 72 patients who underwent allo-HSCT with major or bidirectional ABO mismatch. Cumulative incidence at Day +60 was 6.9% (5/72) at our center. All donor and recipient blood groups were A+ and O+ , respectively. In the first three cases we reported, patients received erythropoietin, plasma exchange, and donor lymphocyte infusion, but none of them had any effect. After 4 weeks of treatment with low dose rituximab (100 mg/week) combined with avatrombopag (40 mg/day), favorable outcomes were obtained. According to the aforementioned experience, Cases 4 and 5 were administered low-dose rituximab and avatrombopag in 3 months after transplantation, and erythroid response was observed on 3 weeks after treatment. Our patients tolerated low-dose rituximab and avatrombopag well and experienced rapid efficacy, with a median duration of 3 weeks. Furthermore, no severe infection or thrombocytosis necessitated a dose adjustment. Low-dose rituximab and avatrombopag may be an effective treatment for patients with PRCA after major ABO-incompatible allo-HSCT. The patients should be treated at least 90 days post transplantation if conventional erythropoietin therapy fails.

Low- and intermediate-risk myelodysplastic syndrome with pure red cell aplasia

ABSTRACT Objectives Our aim is to investigate the clinical characteristics of low- and intermediate-risk myelodysplastic syndrome (MDS) with pure red cell aplasia (PRCA). Methods We retrospectively reviewed the patients of low- and intermediate-risk MDS patients who had been diagnosed with PRCA in our hospital between January 2010 and December 2019. Results There were 6 low- and intermediate-risk MDS patients with PRCA in our study, 1 male and 5 females, with a median age of 63.5 (50-75) years. It accounted for 7.7% (6/78) of all diagnosed PRCA cases and 1.67% (6/359) of diagnosed MDS cases during the same period. All patients were treated with multiple drugs, including recombinant human erythropoietin, cyclosporine, glucocorticoids, androgen, sirolimus, intravenous immunoglobulin and decitabine. Two patients achieved complete remission, two patients achieved partial remission and became blood transfusion independent. Two patients had no response and one patient died. Conclusion Low- and intermediate-risk MDS with PRCA was difficult to treat, but the prognosis was good.

Antibody-mediated pure red cell aplasia related with epoetin-beta pegol (C.E.R.A.) as an erythropoietic agent: case report of a dialysis patient

BackgroundErythropoietin-stimulating agents (ESAs) are used to treat anemia in patients with chronic kidney disease, enabling maintenance of stable hemoglobin levels and eliminating the need for multiple transfusions. Epoetin-beta pegol (C.E.R.A.) is a continuous erythropoietin receptor activator created by integrating a large methoxy-polyethylene-glycol-polymer chain into the erythropoietin molecule, which provides it with a longer half-life. On rare occasions, cases of antibody-mediated pure red cell aplasia (PRCA) related to ESAs are reported. They are characterized by abrupt onset of severe transfusion-dependent anemia, despite ESA therapy. We herein report a case of antibody-mediated PRCA in a dialysis patient receiving C.E.R.A.Case presentationA 44-year-old man with end-stage renal failure had been receiving continuous ambulatory peritoneal dialysis for 2 years. C.E.R.A. was administered subcutaneously as a sole ESA once a month at the hospital since 4 years ago for the treatment of renal anemia and his hemoglobin level was well controlled at 12 g/dl. From 10 months before diagnosis, however, his hemoglobin level suddenly declined, necessitating frequent transfusions. Based on the results of a bone marrow examination and detection of anti-C.E.R.A. antibodies, the patient was diagnosed with antibody-mediated PRCA. After successful elimination of the antibodies using oral prednisolone plus cyclosporine, the patient was re-administrated C.E.R.A. intravenously, as there are few reports of antibody-mediated PRCA related to ESA using that administration route. He responded to the C.E.R.A., and his anemia dramatically improved, eliminating the need for blood transfusions.ConclusionsThis is the first reported case of recovery from an antibody-mediated PRCA with C.E.R.A. after its re-administration following a reversal of the antibody. It has been suggested that the additional large pegylation chain makes C.E.R.A. less likely to trigger antibody generation than other ESAs. Following successful treatment of antibody-mediated PRCA using immunosuppressive therapy, C.E.R.A. can be re-administered intravenously to treat renal anemia.

Investigating Serious Adverse Drug Reactions in Patients Receiving Erythropoiesis-Stimulating Agents: A Root Cause Analysis Using the "ANTICIPATE" Framework.

Unexpected serious adverse drug reactions (sADRs) affecting patients with chronic kidney disease (CKD) who received erythropoiesis-stimulating agents were identified by study co-authors. These included pure red cell aplasia (PRCA) after administration of the Eprex formulation of epoetin or the epoetin biosimilar HX575 and fatal anaphylaxis associated with peginesatide, an erythropoietin receptor agonist. We developed and applied a structured framework to describe these sADRs, including root cause analyses and eradication efforts. A 10-step framework termed "ANTICIPATE," focusing on signal identification, incidence, causality, and eradication guided our evaluations. Initial cases were identified by a hematologist (Eprex), clinical study monitors (HX575), and 4 nurses (peginesatide). The number of persons with individual ADRs was 13 PRCA cases for epoetin, 2 antibody-mediated PRCA cases for HX575, and 5 fatal anaphylaxis cases for peginesatide. Initial incidence estimates per 1000 treated persons were 0.27 for Eprex-associated PRCA, 11 for HX575-associated PRCA, and 0.38 for peginesatide fatalities. Likely causes were subcutaneous administration of epoetin formulated with polysorbate 80 (Eprex), tungsten leaching from pins included in product syringes (HX575), and inclusion of a phenol stabilizer (peginesatide). Eradication strategies included restricting Eprex administration to the intravenous route, excluding tungsten from HX575 syringes, and for peginesatide, proposed eradication was to return to single-dose vials without preservatives. Although the number of cases of each sADR was small, eradication was successful for 2 sADRs, and a proposed eradication was developed for a third sADR. The structured framework used to describe the above 3 sADRs in patients with CKD can also be used in other clinical settings.

Use of Nandrolone Decanoate in Treatment of Pure Red Cell Aplasia Secondary to Diclofenac Administration: A Case Report

Pure red cell aplasia (PRCA) is a disorder that leads to a nonregenerative anemia that results from erythroid precursors failing to reach maturity in the bone marrow, whereas the numbers of mature myeloid and megakaryocytic cells remain normal. PRCA can be induced by autoimmune processes, infections, drugs, toxins, and radiation, and is diagnosed by a bone marrow cytology examination after excluding the most common causes of nonregenerative anemia. Immunosuppressive therapies are used to treat PRCA, and usually involve the use of glucocorticoids, cyclosporin, or azathioprine. Alternatively, although little studied in veterinary medicine, drugs which stimulate bone marrow (e.g., nandrolone decanoate) have been mentioned as possible therapeutic agents. A case of PRCA that presented at the Veterinary Teaching Hospital of the Faculty of Veterinary Medicine and Animal Science (UNESP)-Botucatu, Brazil showed a good therapeutic response to weekly administration of nandrolone decanoate. Therefore, it was concluded that bone marrow stimulants might improve the quality of life of PRCA patients, provided they are used with caution and under close clinical supervision.

Subcutaneous Low Dose Alemtuzumab: Role As a Salvage Therapy in Immune -Mediated Marrow Failure Conditions

▪Aplastic anemia (AA), pure red cell aplasia (PRCA), pure white cell aplasia (PWCA), idiopathic neutropenia (IN) and T cell large granular lymphocytic leukemia (LGL) are bone marrow failure (BMF) conditions unified by immune-mediated pathogenesis leading to cytopenias. Intravenous alemtuzumab, a CD52 monoclonal antibody approved for the treatment of chronic lymphocytic leukemia (CLL) and used for relapsed AA, has a response rate in AA of 37-58%. However, dosing and route was likely based on those used in CLL regimens and resulted in significant immunosuppressive complications.Here we summarize our experience with sc alemtuzumab given at the maximum dose of total 100 mg as etiologic treatment (either salvage therapy or preferred therapy) to patients with various BMF. We investigated the therapies administered to patients seen at the Cleveland Clinic or at the University of Naples (NCT00895739) between years 2002-2015.Of 484 patients with BMF conditions (Cleveland: AA: 204, LGL: 174, PRCA: 56; Naples: AA: 24, LGL: 2, PRCA: 14), 65 patients with AA (N=22), PRCA (N=22), LGL (N=18) and 3 cases of IN/PWCA were treated sc alemtuzumab, given according 2 distinct schedules: i. initial dose of 3 mg sc followed by 10 mg once or twice weekly for at least 8 consecutive weeks; ii. 4-5 day dose escalation (3-10-30-30-30 mg) regimen. In both schedules, some patients received a much longer course with maintenance treatment or occasional boosts to prevent or treat relapse. Patients received bactrim and acyclovir prophylaxis, IVIG for hypoglobulinemia and underwent CMV monitoring. The median age of patients was 57.5 years (range: 31-84 years). Alemtuzumab was used as salvage therapy in Cleveland (except for 3 AA cases with contraindication to anti-thymocyte globulin or cyclosporine), whereas in Naples untreated patients were allowed per protocol. As a result, patients had a median of 2 lines of therapy (range: 0-6), had either untreated (35%), relapsed (22%) or refractory (43%) BMF condition. Among the 22 AA patients 12 were untreated, or had relapsed (N=4), or refractory disease (N=6), with concomitant PNH clone in 8/22 patients. LGL patients (N=18) treated with alemtuzumab were younger, had a median of 2 prior therapies, 50% were STAT3 mutants, with comparable degree of cytopenias but excess splenomegaly (60% vs. 38%, p=.012) at presentation, compared to the remainder LGL cohort. Amongst these patients, 18% had relapsed LGL while the rest had refractory disease. PRCA cases treated were either idiopathic (N=18, of whom 3 associated with thymoma) or LGL-associated (N=4); this group was very heterogeneous, including 9 untreated patients (in Naples) and a subgroup of heavily pretreated patients (5 with refractory disease) with a median of 5 prior therapies, with mean hemoglobin of 7.5 g/dL. Among the group of PWCA/IN, one case of PWCA was LGL-associated.The treatment was well tolerated in 92% of the patients, except in four patients who did not complete treatment course due to adverse events. The main adverse events include infectious complications with 7/65 developing CMV reactivation, 4/65 HSV reactivation, and more rarely other viral reactivation (VZV and HBV, 1/65 each). Two fatal infections were recorded: 1 fungemia (heavily pretreated with other therapies) and 1 JCV-related PML (in a patients also receiving chemotherapy for refractory thymoma).The overall response rate was 55%; by disease subtype 54% of AA, 44% of LGL, 59% of PRCA and all three cases of PWCA/IN responded. The median time to response in AA was 12 weeks (range: 6-24 weeks), and responses lasted a median of 6 months (range: 2-72 months). In AA, we observed responses in 72% of the cases treated with almetuzumab upfront and 45% of the relapsed/refractory disease. Similarly in PRCA cases, 77% of the alemtuzumab upfront and 46% of the relapsed/refractory disease responded. With a median follow up >4 years, no late treatment-related complication emerged; treatment failures were mostly due to relapses (sometimes refractory to further immunosuppressive treatment), with clonal evolution around 15% (mostly in non-responders).In summary, low-dose sc alemtuzumab is a reasonable alternative option for patients with BMF conditions, especially in relapsed/refractory cases; patients need to be monitored with a heightened vigilance for infectious complications, as well as for possible recurrence of their underlying disease. DisclosuresRisitano:Alexion Pharmaceuticals: Other: lecture fees, Research Funding; Alnylam: Research Funding; Rapharma: Research Funding; Novartis: Research Funding.

Adult Patients with Acquired Pure Red Cell Aplasia: Treated By Cyclosporine a and/or Corticosteroids--Single Center Experience

▪Objective: Adult pure red cell aplasia (PRCA) is a syndrome characterized by a severe normocytic anemia, reticulocytopenia, and absence of erythroblasts from an otherwise normal bone marrow. Immunosuppressive therapy has been used as the initial treatment for acquired chronic PRCA. This article aims to evaluate the efficacy of cyclosporine A, and/or corticosteroids, and possible factors influencing it.Methods: 34 cases of PRCA were retrospectively analyzed at our institution.Clinical data of 23 inpatient cases and 11 outpatient cases from 2009 October to 2016 March were collected. These patients were treated by cyclosporine A (CsA), and/or corticosteroids (CS).Results: The causes of PRCA were as follows (table 1): idiopathic (15 cases, 44.1%), thymoma-associated (5 cases, 14.7%), and large granular lymphocyte (LGL) leukaemia-associated (7 cases, 20.6%), virus infection (4 cases, 11.7%), major ABO-mismatched allogeneic haematopoietic stem cell transplantation (1 case, 2.94%), rheumatoid arthritis (1 case, 2.94%), antierythropoietin antibody-mediated (1 case, 2.94%). One patient was lost to follow-up. Two patients were not evaluable for response due to short observation period (<3 months). In idiopathic PCRA, complete remission (CR) was achieved in 4 of 14 cases (28.6%), and partial remission (PR) was achieved in 7 patients (50.0%), while 1 case (7.1%) was still transfusion dependent and 2 deaths(14.3%). In secondary PRCA, complete remission (CR) was achieved in 6 of 17 cases (35.3%, 3 LGL, 2 thymoma, 1 others), and partial remission (PR) was achieved in 3 patients (17.6%, 1 LGL, 2 others ), while 7 case (41.2%, 3 LGL, 2 thymoma, 2 others)) were still transfusion dependent and 1 death(5.9%, thymoma). It showed that the initial rate of CR in CsA-containing group was higher than CS alone (33.3% vs 0%, P=0.028). In 22 refractory and relapsed PRCA patients, 6 out of 10 (60%) refractory patients and 5 out of 12 (41.7%) relapsed patients achieved remission(table 2). The cumulative rate of CR of CsA alone, CS alone, CS+CsA and other immunosuppressive agents were 27.8%, 6.67%, 66.7%, 10%. The cumulative rate of CR of the combination of CS and CsA was higher than CS alone or CsA alone (66.7% vs 18.2%, P=0.028). The response rate of CS or CsA was higher than other immunosuppressive agents (69.2% vs 20%, P<0.01). The age, gender, the percent of reticulocyte and absolute number of lymphocyte in peripheral blood, and etiology did not influence the response rate. (table 3)Conclusion: Thymoma and LGL are the two common causes of secondary PRCA. CsA and/or CS are effective in treating PRCA.The combination of CS and CsA was more effective in achieving CR than CS alone or CsA alone. It was suggested that we might choose the therapy which contains CsA as the initial induction therapy. Other immunosuppressive agents (tacrolimus or mycophenolate mofetil) was less effective in refractory and relapsed PRCA patients. And it was still needed to explore a more effective therapy for refractory and relapsed PRCA patients. [Display omitted] [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Primary acquired chronic pure red cell aplasia refractory to standard treatments: remission with rituximab.

TO THE EDITOR: Pure red cell aplasia (PRCA) is a rare syndrome caused by erythropoietic hypoplasia in the absence of leukocytopenia and thrombocytopenia. It is characterized by severe normocytic and reticulocytopenic anemia, with a normally cellular bone marrow (BM) but devoid of erythroblasts [1]. The acquired form of PRCA is a chronic illness that is often diagnosed in conjunction with a variety of diseases [1], such as lymphoproliferative disorders [2], viral infections, autoimmune hemolytic anemia (AIHA) [3], rheumatologic disorders [4], and allogeneic stem cell transplantation [5]. However, this disorder is rarely diagnosed as an idiopathic condition. Acquired PRCA is managed as an immunologically mediated disease, using immunosuppressive therapy (IST) with corticosteroids and cyclosporine A (CSA) as the treatments of first choice [1]. As alternative and salvage treatment, rituximab has been reported to be highly effective [2,3,4,5]; however, to the best of our knowledge, no case of idiopathic PRCA managed with this agent has been reported. A 63-year-old woman was diagnosed in June 2003 as having PRCA after the discovery of isolated normocytic and reticulocytopenic anemia, the course of which had been insidious and progressive. All other possible underlying causes of erythroblastopenia were ruled out by appropriate investigations (Table 1); other laboratory and radiological evaluations revealed no abnormal findings. The patient had required transfusions of almost 2 units of packed red blood cells (RBC) every 2 to 3 weeks. Once the diagnosis was made, she was started on CSA plus corticosteroids, and soon achieved full recovery from BM erythropoiesis and attained normalization of peripheral blood counts. The patient no longer required transfusions. This was considered complete remission (CR) of PRCA. Therefore, the dosage of CSA was gradually reduced and discontinued. However, there was a progressive loss of response, and CSA was resumed in February 2007 due to a full relapse. The patient achieved a second CR, and the dosage of CSA was carefully tapered. However, the patient experienced progressive chronic renal failure (CRF) in January 2011, which fully resolved after discontinuation of CSA. PRCA recurred soon after, and the patient again required frequent RBC transfusions. When she required approximately 4 RBC units per month, steroids were retried, but without any benefit. Azathioprine was tried without any response. By May 2013, the need for transfusions had reached about 6 RBC units/month, and direct and indirect Coombs blood compatibility tests became positive with the appearance of anti-IgG autoantibody; therefore, the availability of required transfusions became a concern due the difficulty of finding compatible RBC units. In view of this life-threatening complication and a severe hematological condition refractory to all standard treatments for PRCA [1], rituximab was started as a salvage measure at a dose of 375 mg/m2/week for a total of 4 cycles, after the patient gave properly informed consent. Given the lack of experience with rituximab in the setting of primary PRCA, this treatment schedule was derived from that reported as safe and effective in patients with PRCA secondary to lymphoproliferative disorders [2]. After the second dose of rituximab, she exhibited a striking rise in her reticulocyte count and an increase in hemoglobin level. Thus, a third CR was achieved and was maintained during the subsequent 24 months (Fig. 1). In conclusion, the present letter describes a case of acquired chronic primary PRCA of idiopathic origin, refractory to standard measures, with remission on rituximab salvage treatment. To the best of our knowledge, this is the first report of idiopathic PRCA managed with rituximab. In our experience, this agent provided important clinical benefits in an elderly patient with a 12-year PRCA history, during which she had become intolerant/unresponsive to the majority of immunosuppressive agents used in this difficult-to-treat disorder. The course of disease and repeated responses to IST pointed to a possible underlying autoimmune pathogenesis. Although this hypothesis has not been proven by extensive clinical and laboratory evaluations; for this case, rituximab was highly effective in inducing long-lasting remission without any adverse effects.

Pure Red Cell Aplasia - a New Manifestation of CTLA4 Mutation

The cytotoxic T lymphocyte antigen-4 (CTLA4) is an essential negative regulator of immune responses. Its loss causes fatal autoimmunity in mice. Patients with heterozygous mutations in CTLA4 were recently reported to present with an autosomal dominant immune dysregulation syndrome characterized by hypogammaglobulinemia, recurrent infections and multiple autoimmune clinical features (Schubert, D. et al., Nat. Med. 20: 1410-1416, 2014; Kuehn, H.S. et al., Science 345, 1623-1627, 2014). Here we report a family with a CTLA4 mutation that presents with hematological manifestations not previously associated with CTLA4 loss.The index case was a girl referred to our hospital with a very severe thrombocytopenia and anemia at the age of 17. Bone marrow examination revealed no megakaryocytes and just a few erythroblasts. In contrast, granulopoiesis was normal and clonal lymphocytes were not detected. No etiology of the lack of thrombopoiesis and erythropoiesis was discovered. Lack of response to high-dose steroid treatment, platelet counts below 10x109/l, short-lasting effect of transfused platelets and a bleeding tendency urged us to start treatment with horse anti-thymocyte globulin (ATG) and cyclosporine after 2 months. A positive clinical response was observed in 2 weeks. Hb and platelet counts were normalized by 4 weeks, and all medication discontinued by 5 months. Two months later, the patient suffered from generalized tonic-clonic seizures. MRI revealed multiple cerebral lesions, lymphadenopathy and multiple infiltrates in lungs and kidneys. A core kidney biopsy revealed no clonal lymphoid infiltrates. A cerebral biopsy suggested crystal-storing histiocytosis. Steroids were administered, and the infiltrates disappeared gradually during the following months. More than two years later the patient suffered from a Salmonella-induced gastroenteritis, and again she became severely anemic. Her bone marrow revealed now lack of erythropoiesis whereas thrombopoiesis and granulopoiesis were normal. She was then diagnosed with pure red cell aplasia (PRCA).An uncle of the index case had been referred to us with the diagnosis MDS at the age of 47, one year prior to the index patient's last referral and PRCA diagnosis. Dysplasia was not verified, and since the patient completely lacked red cell precursors, the diagnosis was changed to PRCA. In addition, both he, his mother and the index case had been suffering from diarrhea for years without any diagnosis. His mother also had pernicious anemia.The two familial cases of PRCA, a rare hematological manifestation, prompted us to conduct whole exome sequencing which revealed that the two patients with PRCA were both heterozygous for a 5 base pair-insertion in exon 1 of the CTLA4 gene, leading to a frameshift and premature stop codon causing haploinsufficiency. Familial segregation was tested by Sanger sequencing and showed that also the grandmother and the mother of the index case were carriers of the same mutation.Functional assays of our index patient, the two family members with autoimmunity (her uncle and grandmother) and her unaffected mother revealed fewer CD19+ B- and naïve T cells than normal. Furthermore, we found dysregulation of regulatory T (Treg) cells, reduced levels of T cell CTLA4, particularly FoxP3+ Treg CTLA4 (mean fluorescence intensity as well as frequency of CTLA4+ T cells and Tregs) and signs of hyperactivity of effector T cells. Our findings were as reported in the above cited publications.The discovery of a CTLA4 mutation in this family with 3 affected members and one unaffected carrier might have immediate implications for our index patient. As she did not respond to high-dose steroids as her uncle did, her genetic diagnosis opens up to additional treatment opportunities. Actual medication for patients with mutations in CTLA4 and autoimmunity could be mTOR inhibitors like sirolimus and possibly CTLA4 fusion proteins (abatacept and belatacept). These fusion proteins bind to CD80 and CD86 and inhibit CD28-mediated immune activation.In conclusion, we have detected a mutation in the CTLA4 gene with corresponding T cell aberrations in this family through the new manifestation PRCA. These findings may be of clinical importance for the family we have characterized as well as for other patients with similar manifestations. DisclosuresOff Label Use: Abatacept and belatacept are fusion protein consisting of a part of CTLA4. It can modulate a signal necessary for activating specific T lymphocytes and can be effective in patients with CTLA4 mutations..

Feline non-regenerative immune-mediated anaemia: features and outcome in 15 cases.

Pure red cell aplasia (PRCA) and non-regenerative immune-mediated haemolytic anaemia (NRIMHA) are uncommon causes of non-regenerative anaemia affecting the bone marrow in the cat. This retrospective study aimed to describe the clinical features, treatment and outcome (remission and survival) of cats with these disorders. Cases of PRCA and NRIMHA presenting between 2009 and 2013 were retrieved. Clinical features including signalment, history, clinical signs and diagnostic investigations were recorded, as well as treatment(s) used and outcome (remission and survival). Outcome was compared for PRCA and NRIMHA. Fifteen cats met inclusion criteria: seven with PRCA and eight with NRIMHA. The majority (12/15) were younger than 3 years of age. Volume overload was common (8/11). Treatment with whole blood transfusions with or without Oxyglobin was necessary in most cats (14/15) and resulted in congestive heart failure in one cat. Most cats (11/15) achieved remission 12-42 days after starting immunosuppressive treatment. Treatment protocols associated with remission were glucocorticoids alone (remission in 6/7 cats), glucocorticoids and chlorambucil (remission in 3/6 treated cats), glucocorticoids and ciclosporin (one cat only) and ciclosporin alone (one cat only). Relapse was observed in 3/11 cats, and 8/11 cats were still receiving treatment at the time of follow-up. Outcome (remission and survival) did not differ between PRCA and NRIMHA. PRCA and NRIMHA are uncommon causes of anaemia in predominantly young cats. The prognosis is reasonable, with a mortality rate of 27%, and it can take at least 6 weeks before remission is observed. Following clinical remission, gradual withdrawal of immunosuppressive treatments should be attempted, with close monitoring for relapse; some cats may require long-term treatment. This study is the first to report the use of chlorambucil as an adjunctive immunosuppressant in these cases. Outcome did not differ for PRCA and NRIMHA.

Long-term outcome of patients with acquired chronic pure red cell aplasia (PRCA) following immunosuppressive therapy: a final report of the nationwide cohort study in 2004/2006 by the Japan PRCA collaborative study group.

Immunosuppressive therapy has been employed as the initial treatment for acquired chronic pure red cell aplasia (PRCA), such as idiopathic, thymoma-associated, or large granular lymphocyte (LGL) leukaemia-associated PRCA, which is thought to be immune-mediated. To explore the overall long-term outcome following immunosuppression and to identify the risk factors for death in these disorders, we conducted nationwide surveys in Japan 2004 and 2006, and identified a total of 185 patients with acquired chronic PRCA, including 72 idiopathic, 41 thymoma-associated and 14 LGL leukaemia-associated cases of PRCA for whom data was available. The present study evaluated 127 patients with these three subsets of PRCA. The median overall survival has not yet been reached in idiopathic PRCA. The estimated median overall survival times in patients with thymoma-associated and LGL leukaemia-associated PRCA were 142·1 and 147·8months, respectively. Twenty-two deaths were reported, and the response to induction therapy and relapse of anaemia were found to be associated with death. The major causes of death were infection in seven patients and organ failure in another seven patients. The results suggest that maintenance therapy and the management of infectious complications are crucial for improving the prognosis of chronic PRCA.

Incidence of erythropoietin antibody-mediated pure red cell aplasia: the Prospective Immunogenicity Surveillance Registry (PRIMS)

BackgroundSubcutaneous administration of Eprex® (epoetin alfa) in patients with chronic kidney disease (CKD) was contraindicated in the European Union between 2002 and 2006 after increased reports of anti-erythropoietin antibody-mediated pure red cell aplasia (PRCA). The Prospective Immunogenicity Surveillance Registry (PRIMS) was conducted to estimate the incidence of antibody-mediated PRCA with subcutaneous administration of a new coated-stopper syringe presentation of Eprex® and to compare this with the PRCA incidence with subcutaneous NeoRecormon® (epoetin beta) and Aranesp® (darbepoetin alfa).MethodsPRIMS was a multicentre, multinational, non-interventional, parallel-group, immunogenicity surveillance registry. Adults with CKD receiving or about to initiate subcutaneous Eprex®, NeoRecormon® or Aranesp® for anaemia were enrolled and followed for up to 3 years. Unexplained loss or lack of effect (LOE), including suspected PRCA, was reported, with antibody testing for confirmation of PRCA.ResultsOf the 15 333 patients enrolled, 5948 received Eprex® (8377 patient-years) and 9356 received NeoRecormon®/Aranesp® (14 286 patient-years). No treatment data were available for 29 patients. Among 23 patients with LOE, five cases of PRCA were confirmed (Eprex®, n = 3; NeoRecormon®, n = 1; Aranesp®, n = 1). Based on exposed time, PRCA incidence was 35.8/100 000 patient-years (95% CI 7.4–104.7) for Eprex® versus 14.0/100 000 patient-years (95% CI 1.7–50.6) for NeoRecormon®/Aranesp®. The incidence of PRCA with Eprex® was not significantly different versus comparator ESAs (rate ratio: 2.56; 95% CI 0.43–15.31). An analysis based on observed time produced similar findings.ConclusionThis large, prospective registry demonstrates that PRCA is rare with subcutaneous administration of either the new coated-stopper syringe presentation of Eprex®, or NeoRecormon® or Aranesp®.

Subcutaneous bortezomib is highly effective for pure red cell aplasia after ABO‐incompatible haematopoietic stem cell transplantation

Subcutaneous bortezomib is highly effective for pure red cell aplasia after <scp>ABO</scp>‐incompatible haematopoietic stem cell transplantation

Rechallenge with intravenous recombinant human erythropoietin can be successful following the treatment of anti-recombinant erythropoietin associated pure red cell aplasia

Anti recombinant human erythropoietin (r-HuEpo) associated pure red cell aplasia (PRCA) is an immunologic adverse effect of using subcutaneous r-HuEpo. Immunosuppressive agents have been suggested as treatment of this serious complication. After the reversal of anti-r-HuEpo antibody, the patients continue to have renal anemia and require long-term blood transfusion, albeit less frequently than when the antibody is positive. It is controversial whether re-challenging the patients with r-HuEpo is appropriate because re-challenging may cause the reappearance of the antibody. To balance the risk of antir-HuEpo antibody reappearance and longterm blood transfusion complications, we re-challenged r-HuEpo in five anti-r-HuEpo associated PRCA cases after a successful reversal of antibody using prednisolone in combination with cyclophosphamide. The rechallenge was performed intravenously since there were no reports of anti-r-HuEpo associated PRCA cases using this administration route. The duration after the reversal of antibody was 2.4 months before the re-challenge. Two patients were immediately re-challenged as soon as the antibodies reversed. After rechallenge with intravenous r-HuEpo, all patients responded to r-HuEpo: target level of Hb was maintained, blood transfusion was not required, and anti-r-HuEpo was consistently negative. All patients were followed for at least 6 months after re-challenge. Our data suggest that re-challenge with intravenous r-HuEpo can successfully treat anti- r-HuEpo associated PRCA.

Steroid Responsive T-Cell Mediated Pure Red Cell Aplasia Following Allogeneic Hematopoietic Stem Cell Transplantation

Pure red cell aplasia (PRCA) is an unusual complication following allogeneic hematopoietic stem cell transplantation (HSCT), the true incidence of which is not known. Almost all cases reported in the literature describe major ABO-incompatibility between the recipient and the donor as the major risk factor for this complication. Delayed recovery of reticulocyte counts and hypoplasia of erythroblasts in the marrow is attributed to incompatible hemagglutinins in recipients. There are reports of successful treatment of PRCA using different strategies include rapid tapering of calcineurin inhibitors, corticosteroids, donor lymphocyte infusion, rituximab, and/or plasma exchange. Additional causes of PRCA following allogeneic HSCT include parvovirus B19 infection and graft-versus-host disease (GVHD). The pathogenesis of PRCA in parvovirus infection is thought to be viral-mediated suppression of erythroid precursors in the bone marrow and this is due to the tropism of this virus for erythroid progenitor cells. Nonmyeloablative and reduced intensity conditioning regimens have been reported to have an increased risk of PRCA due to persistence of recipient lymphocytes. Here we report two cases of PRCA following allogeneic HSCT from major ABO mismatched donors. Both cases were correlated with the presence of a T-cell clone in the peripheral blood and bone marrow, and there was complete resolution of anemia with a short course of steroid treatment, as well as disappearance of the T-cell clone. Patient # 1 – A 24 year old female of Mediterranean descent underwent an HLA- 8/10 matched and major ABO-mismatched sibling donor bone marrow transplant for Sickle-Beta Thalassemia. She received a myeloablative but reduced toxicity conditioning regimen consisting of busulfan 16mg/kg, fludarabine 140mg/m2, cyclophosphamide 105mg/kg, and alemtuzumab 52mg/m2. Her immediate post-transplant course was relatively benign and significant for a mild CMV colitis which responded with resolution after treatment with anti-viral therapy. Her red cell transfusion needs had significantly decreased to every four weeks by day 130. However, at day 146 from HSCT, she started requiring red cell transfusions every two weeks, with a drop in the reticulocyte count to 0.6%. No antibodies were detected, and the patient was negative for parvovirus B19 and did not have any evidence of GVHD. However, her bone marrow showed an marked erythroid hypoplasia, and was positive for a T-cell clone with gamma chain gene rearrangement in the T-cell receptor. Due to a new onset of transfusion need, she was treated with a short course of steroids with an excellent response and disappearance of the T-cell clone from peripheral blood. She remained on immunosuppression during this entire period with a calcineurin inhibitor. Patient# 2 – A 10 year old Hispanic girl underwent a 10/10 HLA-matched and major ABO-mismatced sibling donor bone marrow transplant for idiopathic acquired severe aplastic anemia. Her preparative regimen consisted of 200 mg/kg of cyclophosphamide and 16mg/kg of rabbit-anti-thymocyte globulin. Her immediate post-transplant course was complicated by E.coli bacteremia. She had prompt engraftment and became transfusion independent on day 86. A cyclosporine taper was initiated at day 100 but held at day 119 when anemia was first noted. Peripheral blood showed a T-cell clone with gamma and beta chain gene rearrangement. She was started on a moderate dose of steroids with a good response, and has been tapered down to physiologic replacement dose of steroids with normal Hb and transfusion independence. With the resolution of anemia, the gamma chain gene rearrangement is not seen in the T-cell clonality assay, however, the beta chain gene rearrangement persists. To our knowledge, this is the first report of a T-cell mediated PRCA following allogeneic HSCT. Moreover, the PRCA was steroid responsive and not associated with GVHD in both the patients. Disclosures:No relevant conflicts of interest to declare.

English

Anemia in children may arise from a wide variety of pathogenetic mechanisms that include congenital and acquired disorders. Often the diagnostic considerations include disorders that are not seen commonly in adults and lifelong disorders that arise in children and persist throughout life. Consideration of diverse causes of anemia such as red cell membrane disorders, red cell enzymopathies, congenital dyserythropoietic anemias, congenital sideroblastic anemias, and hereditary pure red cell aplasia (Diamond-Blackfan anemia), as well as infectious causes such as parvovirus B19 infection, often is required when diagnosing anemia in an infant or young child. Knowledge of these entities that are important causes of anemia in the pediatric population, including clinical manifestations and laboratory workup, will aid in recognition of the specific disease entities and effective workup of pediatric red cell disorders. Inherited and acquired red cell disorders in children include a diverse group of disorders that include red cell enzyme disorders, red cell membrane disorders, congenital dyserythropoietic anemia, sideroblastic anemia, hemoglobinopathies, and red cell aplasias. Most of these disorders are manifested in the child by anemia with hypoproliferative or hemolytic mechanisms underpinning the development of anemia. Hypoproliferative anemia arises secondary to decreased overall RBC precursors or ineffective erythropoiesis, suggesting an abnormality in bone marrow production or erythroid precursors. Conversely, the anemia may be hemolytic in nature, reflecting abnormalities in RBC structure or biologic function that affect RBC life span and are associated with normal to increased erythropoiesis. Clinical manifestations, RBC characteristics, specific laboratory testing, and bone marrow findings are all useful in trying to classify the cause of the anemia and define a specific disease process. INTRODUCTION: Pure red cell aplasia (PRCA) is an uncommon disorder in which maturation arrest occurs in the formation of erythrocytes. Erythroblasts are virtually absent in bone marrow; however, WBC and platelet production is normal. The anemia due to PRCA is usually normocytic but can be macrocytic. In 1922, Kaznelson recognized that this condition was a different entity from aplastic anaemia, which presents with pancytopenia. The characteristics of PRCA include a severe anemia, a reticulocyte count of less than 1%, and the presence of less than 0.5% mature erythroblasts in the bone marrow. The bone marrow is usually normocellular. The etiology of PRCA is heterogeneous. A congenital form of PRCA was initially described by Joseph in 1936 and by Diamond and Blackfan in 1938. Congenital PRCA is a lifelong disorder and is associated with physical abnormalities. PRCA can be transient and reversible. Transient erythroblastopenia of childhood (TEC) can occur after viral infections. PRCA due to medications is also often reversible when these medications are discontinued. PRCA due to infections is often reversible. In adults, most cases of chronic PRCA are idiopathic, and a cause cannot be established. Secondary PRCA occurs in patients with conditions such as autoimmune disorders, thymomas, hematologic malignancies,

Pure red cell aplasia with thymoma/T-cell large granular lymphocyte leukemia: two cases report and literatures review

To investigate the clinical and laboratory features of 2 cases of pure red cell aplasia (PRCA) with thymoma/T-cell large granular lymphocyte leukemia (T-LGLL), and to improve the recognition of the disease and the role of lymphocyte in its mechanism. Two cases of PRCA with thymoma/T-LGLL were reported and the related literatures were reviewed. Case 1 was a 63-years old male with hemoglobin level of 54 g/L at admission. Case 2 was a 52-years old female with hemoglobin level of 79 g/L at admission. They were both diagnosed as PRCA with thymoma before admission to our hospital and had no benefit from their thymectomy. Further examinations in our hospital showed that CD3⁺CD4⁻CD8⁺CD57⁺ large granular lymphocytes amplified with clonal TCR rearrangement in their peripheral blood. The diagnosis of PRCA with thymoma/T-LGLL was clarified. Case 1 did not respond to any of the frontline therapies while case 2 responded completely to cyclosporine. Both thymoma and T-LGLL could be the cause of secondary PRCA, lymphocyte proliferation may play critical role in the pathogenesis.

Waldenström's macroglobulinaemia complicated by pure red cell aplasia: a case report.

Waldenstrom's macroglobulinemia (WM), a lymphoplasmacytic lymphoma and immunoglobulin M (IgM) monoclonal gammopathy, is a subtype of plasma cell disorder, an indolent mature B-cell neoplasm associated with bone marrow involvement1. Pure red cell aplasia (PRCA) is characterised by the near complete absence of erythroid precursors in the bone marrow but normal megakaryocytes and granulocytes2. About 80% cases of WM are complicated by normocytic normochromic anaemia, while PRCA, an unusual cause of anaemia in patients with chronic lymphoproliferative disorders, is extremely rare in WM. So far, very few cases of concomitant WM and PRCA have been reported. Here we describe a new patient with acquired PRCA and concurrent WM with the purpose of providing further insight into this rare association.