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

BACKGROUND: 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. STUDY DESIGN AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Refractory pure red cell aplasia associated with T-cell large granular lymphocyte leukemia treated by ruxolitinib.

Acquired pure red cell aplasia (PRCA) is a rare syndrome characterized by normocytic normochromic anemia with severe reticulocytopenia and absence of erythroid precursors in the bone marrow. For refractory PRCA patients, the low response rate and high toxicity of alternative therapies pose a great challenge. T-cell large granular lymphocyte (T-LGL) leukemia is one of the most common conditions in secondary PRCA and also the most difficult form to manage with an inferior treatment response to other secondary PRCA forms. T-LGL leukemia exhibits sustained activation of the intracellular JAK-STAT signaling pathway. We herein report a case of PRCA associated with T-LGL leukemia that had been refractory to multiple lines of therapies and was successfully treated by ruxolitinib. The patient achieved complete remission and tolerated ruxolitinib well without occurrence of neutropenia or thrombocytopenia. This preliminary finding favors ruxolitinib as a potential salvage therapy for refractory PRCA associated with T-LGL leukemia.

STK10 mutations block erythropoiesis in acquired pure red cell aplasia via impairing ribosome biogenesis.

Acquired pure red cell aplasia (PRCA) is anemia associated with the absence of erythroblasts and is characterized by persistent and easy recurrence. However, the underlying mechanisms of acquired PRCA remain obscure, and the role of gene mutations in the pathogenesis of acquired PRCA is not fully characterized. In the present study, we detected thirty newly diagnosed patients with acquired PRCA using whole exome sequencing, and a potential role for STK10 in acquired PRCA was uncovered. The mRNA levels of STK10 in three patients with STK10 mutations were decreased. These three patients had a poor response to immunosuppressive therapy and two died in the follow-up period. Here we report that knockdown of STK10 inhibits erythroid differentiation and promotes apoptosis of K562 cells. We show that knockdown of STK10 resulted in inhibition of ribosome biogenesis and reduced ribosome levels in K562 cells. We also show that the p53 signaling pathway is activated by knockdown of STK10. Our results imply that ribosome biogenesis downregulation together with pathological p53 activation prevents normal erythropoiesis. Our study uncovers a new pathophysiological mechanism leading to acquired PRCA driven by STK10 mutations.

A nomogram model for predicting the efficacy of cyclosporine in patients with pure red cell aplasia.

Pure red cell aplasia (PRCA) is a rare bone marrow disorder characterized by a severe reduction or absence of erythroid precursor cells, without affecting granulocytes and megakaryocytes. Immunosuppressive therapies, particularly cyclosporine, have demonstrated efficacy as a primary treatment. This study aims to develop a predictive model for assessing the efficacy of cyclosporine in acquired PRCA (aPRCA). This retrospective study encompasses newly treated aPRCA patients at the General Hospital of Tianjin Medical University. Diagnosis criteria include severe anemia, and absolute reticulocyte count below 10 × 109/L, with normal white blood cell and platelet counts, and a severe reduction in bone marrow erythroblasts. Cyclosporine therapy was administered, with dose adjustments based on blood concentration. Response to cyclosporine was evaluated according to established criteria. Statistical analysis involved logistic multi-factor regression, generating a predictive model. The study included 112 aPRCA patients with a median age of 63.5 years. Patients presented with severe anemia (median Hb, 56 g/L) and reduced reticulocyte levels. Eighty-six patients had no bone marrow nucleated erythroblasts. Primary PRCA accounted for 62 cases (55.4%), and secondary PRCA accounted for 50 cases (44.6%). Univariate analysis revealed that ferritin, platelet to lymphocyte ratio (PLR), and CD4/CD8 ratio influenced treatment response. Multivariate analysis further supported the predictive value of these factors. A prediction model was constructed using ferritin, PLR, and CD4/CD8 ratio, demonstrating high sensitivity and specificity. The ferritin, PLR, and CD4/CD8-based nomogram showed good predictive ability for aPRCA response to cyclosporine. This model has potential clinical value for individualized diagnosis and treatment of aPRCA patients.

Gilteritinib combined with venetoclax and azacitidine for relapsed acute myeloid leukemia cocurrent with pure red cell aplasia after allogeneic hematopoietic stem cell transplantation: a case report.

Pure red cell aplasia (PRCA) is a rare bone marrow (BM) disorder characterized by ineffective erythropoiesis, reduced reticulocyte count, normocytic anemia, and the absence of erythroid precursors. Here, we present a rare instance of PRCA occurring after ABO-matched allo-HSCT in a refractory/relapsed acute myeloid leukemia (R/R AML) patient. In this case, the patient received a combination treatment of Gilteritinib, Venetoclax, and Azacitidine. Remarkably, this treatment not only reduced myeloblasts but also facilitated the restoration of erythroid hematopoiesis.

Niraparib-induced pure red cell aplasia.

INTRODUCTION: Niraparib, a strong poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitor, contributed significantly to progression-free survival as a maintenance therapy in the platinum-sensitive period in both first-line and recurrent ovarian cancer, regardless of the BRCA mutation. Grade 3-4 anemia, which has a manageable side effect profile, especially hematological, is seen in almost 1 out of every 4 patients. To the best of our knowledge, there has been no reported case of pure red cell aplasia (PRCA) induced by niraparib treatment. CASE REPORT: A 65-year-old woman diagnosed with stage 3 serous carcinoma of the tuba received niraparib front-line maintenance treatment had grade 4 anemia after 3 months of niraparib treatment. She underwent bone marrow aspiration and biopsy because of refractory anemia, which needs red blood cell (RBC) transfusions despite interruption of treatment. MANAGEMENT AND OUTCOME: The patient was treated with 1 mg/kg methyl prednisolone, after histopathological assessment was consistent with PRCA. The hemoglobin count returned to the normal range with steroid treatment. DISCUSSION: In daily practice, it should be kept in mind that in the case of refractory anemia induced by niraparib, the underlying cause might be PRCA and can be improved with steroid administration.

Resistant anemia in a kidney transplant recipient: Pure red cell aplasia due to parvovirus B19 infection.

Anemia in kidney transplant recipients can stem from a diverse array of etiologies, including dietary deficiencies, inflammatory processes, allograft dysfunction, as well as viral and bacterial infections. We present a case of refractory anemia in a 49-year-old male patient occurring within the initial month following a kidney transplant, which persisted despite numerous transfusions, posing a formidable challenge. The patient was maintained on the standard immunosuppressant regimen-Tacrolimus, Mycophenolate, and Prednisolone. Diagnostic evaluations eliminated well-established causes such as dietary deficiencies, gastrointestinal losses, and prevalent infections. Subsequently, after viral PCR testing, a diagnosis of Pure Red Cell Aplasia (PRCA) due to infection with parvovirus B19 was made. Although the patient had a reduction in the immunosuppression drugs and received a course of Intravenous Immunoglobulins (IVIG) on two separate occasions spanning two months, the anemia relapsed. Subsequently, after an additional dose of IVIG with further modification and reduction of the immunosuppressant regimen, including stopping the mycophenolate and switching tacrolimus with cyclosporine, the patient ultimately achieved successful resolution of his symptoms and a significant decrease in viral load. Our case highlights the significance of unconventional etiologies when confronted with anemia in the setting of kidney transplantation. Furthermore, it also provides further insights into therapeutic avenues for addressing PRCA in kidney transplant recipients.

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+CD127low 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+CD127low 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.

Exacerbation of autoimmune hemolytic anemia associated with pure red cell aplasia after COVID-19: A case report.

Autoimmune hemolytic anemia (AIHA) and pure red cell aplasia (PRCA) are rare complications of coronavirus disease 2019 (COVID-19). Herein, we report the case of a 28-year-old Japanese man who showed severe AIHA exacerbation associated with PRCA after COVID-19. AIHA was diagnosed and maintained for 5 years. Approximately 4 weeks after COVID-19, the patient developed severe anemia (hemoglobin level, 3.4 g/dL). Laboratory test results confirmed hemolytic exacerbation of IgG-mediated warm-type AIHA. Despite the hemolysis phase, the bone marrow revealed extreme hypoplasia of erythroblasts with a decreased reticulocyte count, similar to that observed in patients with PRCA. During oral prednisolone treatment, the patient recovered from anemia and showed increased reticulocyte count and reduced hypoplasia of marrow erythroblasts. Exacerbation of AIHA and PRCA was triggered by COVID-19 because other causes were ruled out. Although this case report highlights that COVID-19 could lead to hematological complications such as AIHA and PRCA, the exact mechanisms remain unclear.

Successful treatment of pure red cell aplasia using therapeutic plasma exchange after ABO-incompatible hematopoietic stem cell transplant.

Hematopoietic stem cell transplants (HSCTs) are widely used in the treatment of hematologic malignancies and bone marrow failure syndromes. ABO compatibility is typically of secondary importance, and up to 50% of HSCT are performed in ABO-incompatible pairings. In the literature, pure red cell aplasia (PRCA) occurs in 1% to 50% of all major/bidirectional ABO-incompatible stem cell transplants, but treatment of PRCA remains heterogeneous. Here, we report two cases in which patients with transfusion-dependent PRCA following HSCT were successfully treated with therapeutic plasma exchange (TPE). Case 1: A 52-year-old type O-positive male with acute myeloid leukemia underwent HSCT using apheresis-derived HSCs from a fully human leukocyte antigen (HLA)-matched, related type A-positive male donor. He developed PRCA that was refractory to multiple therapies, so a series of 10 TPE was performed over 3 weeks. Case 2: A 21-year-old type A-positive male with aplastic anemia underwent HSCT using bone marrow-derived HSCs from a fully HLA-matched related type B-positive female donor. He developed PRCA that was refractory to multiple therapies, so a series of 5 TPE was performed over 2 weeks. Case 1: The patient has been transfusion independent since TPE #7, and type A red blood cells (RBCs) were seen on the ABO type after TPE #9. Case 2: The patient has been transfusion independent since after TPE #1, and type B RBCs were seen on the ABO type after TPE #5. TPE was successful in treating two patients with PRCA after ABO-incompatible HSCT transplants. Isoagglutinin titers decreased below the level of detection for both our patients. Ultimately both patients became transfusion independent and showed evidence of erythroid cell recovery.

Pure red cell aplasia occurring during ibrutinib therapy for chronic lymphocytic leukemia.

INTRODUCTION: Chronic lymphocytic leukemia (CLL) has long been known for its complications related to immune deregulation, of which autoimmune cytopenias (AIC) were frequently reported. Ibrutinib has dramatically changed the overall prognosis of patients with CLL. However, whether ibrutinib can induce or aggravate AIC in CLL patients is still disputable. Here we report a CLL patient with pure red cell aplasia (PRCA) occurring during ibrutinib treatment and review available data to discuss the possible role of ibrutinib in developing AIC. CASE REPORT: A 70-year-old female was diagnosed with CLL with indications to initiate ibrutinib treatment given progressive bulky disease. She was admitted for advanced fatigue on the 14th day of ibrutinib monotherapy. A complete blood count revealed severe anemia of hemoglobin (Hb) 37 g/L and a meager reticulocyte count. After excluding other conditions that could cause anemia, PRCA was diagnosed as a complication of CLL. MANAGEMENT AND OUTCOME: Ibrutinib was discontinued on the day of admission. At the same time, the patient received prednisone and intravenous immunoglobulin (IVIg). Five days later, the Hb did not improve. Cyclosporine A (CsA) was added; IVIg was discontinued, and prednisone was tapered. Ten days later, the Hb had risen to 92 g/L with a high reticulocyte count of 0.279 × 1012/L. The CLL treatment restarted with Zanbrutinib in combination with a low dose of prednisone and CsA. Her CLL was in partial remission by the latest follow-up with an average Hb count. DISCUSSION: Our case demonstrates a need to evaluate the risk of developing AIC before initiating ibrutinib. For patients with high-risk factors for AIC episodes, the transient addition of other immunosuppressive therapies should be taken into consideration.

A De Novo Frameshift Mutation in RPL5 with Classical Phenotype Abnormalities and Worsening Anemia Diagnosed in a Young Adult-A Case Report and Review of the Literature.

Diamond-Blackfan anemia (DBA) is a congenital bone marrow failure syndrome associated with malformations. DBA is related to defective ribosome biogenesis, which impairs erythropoiesis, causing hyporegenerative macrocytic anemia. The disease has an autosomal dominant inheritance and is commonly diagnosed in the first year of life, requiring continuous treatment. We present the case of a young woman who, at the age of 21, developed severe symptomatic anemia. Although, due to malformations, a congenital syndrome had been suspected since birth, a confirmation diagnosis was not made until the patient was referred to our center for an evaluation of her anemia. In her neonatal medical history, she presented with anemia that required red blood cell transfusions, but afterwards remained with a stable, mild, asymptomatic anemia throughout her childhood and adolescence. Her family history was otherwise unremarkable. To explain the symptomatic anemia, vitamin deficiencies, autoimmune diseases, bleeding causes, and myeloid and lymphoid neoplasms were investigated and ruled out. A molecular investigation showed the RPL5 gene variant c.392dup, p.(Asn131Lysfs*6), confirming the diagnosis of DBA. All family members have normal blood values and none harbored the mutation. Here, we will discuss the unusual evolution of this case and revisit the literature.

[Analysis of anti-SARS-CoV-2 IgG antibody titers after mRNA booster vaccination in patients with nonmalignant hematological disorders].

In our facility, anti-SARS-CoV-2 mRNA vaccines were given to 21 patients, including 8 with aplastic anemia (AA), 3 with pure red cell aplasia (PRCA), and 10 with immune thrombocytopenic purpura (ITP), and IgG antibody titers were assessed one month after vaccinations. After receiving both a second vaccine and a booster shot, all patients with AA/PRCA treated with cyclosporine A aside from one, had IgG titers that were lower than the median levels of healthy controls. Even if prednisolone (PSL) doses did not go over 10 mg/day, ITP patients receiving PSL therapy were unable to achieve adequate levels of IgG after booster immunizations.

Clinical characteristics and outcomes of 100 adult patients with pure red cell aplasia.

Adult pure red cell aplasia (PRCA) is a rare syndrome characterized by a severe normocytic anemia, reticulocytopenia, and absence of erythroblasts from bone marrow. The standard treatment has not yet been established for PRCA, although cyclosporine (CsA), corticosteroids (CS) showed a response in PRCA. We retrospectively analyzed the clinical data of 60 primary and 40 secondary adult patients with acquired PRCA. The proportion of secondary PRCA is relatively high and commonly associated with large granular lymphocyte leukemia (LGLL) (28 cases, 70.0%). The remission-induced regimens included CS, CsA, or other agents, and the response rate was 66.7%, 71.4%, and 50%, respectively (P = 0.336). When treating with CsA, the response rate of LGLL-associated PRCA was lower than primary PRCA (42.1% vs 85.7%, P = 0.001). Logistic regression analysis showed that ORR was inversely related to LGLL-associated PRCA. LGLL-associated PRCA had poor therapeutic efficacy to CsA.

Immune reconstitution and survival of patients with parvovirus B19 related pure red cell aplasia after haplo-PBSCT.

Parvovirus B19 (PvB19) infection and PvB19 related pure red cell aplasia (PRCA) in recipients with allogeneic hematopoietic stem cell transplantation have been reported sporadically. However, clinical studies with large sample sizes are lacking, especially in patients undergoing HLA-haploidentical peripheral blood stem cell transplantation (haplo-PBSCT). In addition, clinical features, immune reconstitution, and outcomes of these patients are not clear. We conducted a retrospective analysis of 164 patients who received haplo-PBSCT with low-dose anti-thymocyte globulin (ATG) plus low-dose posttransplant cyclophosphamide (PTCy)-based regimen as graft-versus-host disease (GVHD) prophylaxis. We analyzed the incidence of PvB19 related PRCA and compared the clinical characteristics, immune reconstitution, incidence of GVHD, relapse rate, and survival between patients with and without PvB19 related PRCA. A total of 14 (8.5%) recipients developed PvB19 related PRCA after a median of 5.3 months after haplo-PBSCT. These patients with PvB19 related PRCA had slower immune reconstitution, but similar incidences of GVHD, relapse rate, and overall survival compared with recipients without PvB19 related PRCA. PvB19 related PRCA indicated relative delayed and poor immune reconstitution of the recipients early after haplo-PBSCT. PvB19 related PRCA had no effects on GVHD, relapse, and survival.

A pregnant woman with thymoma-associated pure red cell aplasia.

BACKGROUND: Pure red cell aplasia (PRCA) is a hematological disorder characterized by anemia with severe reticulocytopenia caused by a marked reduction in erythroid precursors in the bone marrow. PRCA is known to be associated with pregnancy, but thymoma-associated PRCA during pregnancy is very rare, and its successful management has not been reported. CASE PRESENTATION: A 37-year-old primiparous woman with severe anemia was referred to our center at 27 weeks' gestation. She was diagnosed with PRCA based on bone aspiration findings at 33 weeks' gestation. Magnetic resonance imaging (MRI) revealed an anterior mediastinal mass 4 cm in size suspected of being thymoma. She was therefore diagnosed with thymoma-associated PRCA during pregnancy. Surgery for thymoma was planned after delivery, since the imaging findings were suggestive of early-stage thymoma (Masaoka stage I or II). With transfusion of a total 3,360 ml of red blood cells (RBCs) during pregnancy, the patient gave birth to a baby girl weighing 2,548 g at 40 weeks' gestation. The baby showed transient congenital cutaneous candidiasis. The placental pathology revealed subamniotic inflammation with a fungal structure. Treatment with topical anti-fungal cream immediately ameliorated the baby's skin lesion. Maternal anemia did not improve after delivery; however, the thymoma did not increase in size. At five months after delivery, the mother underwent thymectomy with oral cyclosporine A. A pathological examination revealed Masaoka stage II-a thymoma. She completely had recovered from anemia at six months after surgery. Cyclosporine A treatment was discontinued three years after surgery. Remission has been sustained for four years since surgery. CONCLUSIONS: A very rare case of thymoma-associated PRCA during pregnancy was diagnosed without any subjective symptoms and was expectantly managed, resulting in a good prognosis. Although bone marrow aspiration during pregnancy is an invasive test, it is important to confirm the diagnosis. Conservative management with blood transfusion was possible for early-stage thymoma-associated PRCA during pregnancy. Active surveys, including MRI, for PRCA during pregnancy led to the detection of thymoma at an early stage and the achievement of a preferable pregnancy outcome.

Pure red cell aplasia accompanied by COVID-19 successfully treated using cyclosporine.

A 67-year-old Japanese man was admitted to our hospital with severe coronavirus disease 2019 (COVID-19) in March 2020. Mechanical ventilation was initiated 8 days after admission, due to severe respiratory failure. Multiple severe complications such as liver dysfunction, arrhythmia, brain infarction, and venous thromboembolism were also observed. We initially diagnosed Coombs test-positive warm autoimmune hemolytic anemia. Corticosteroids proved ineffective and anemia worsened with severe erythroid hypoplasia (0.5% erythroblasts in bone marrow), so we diagnosed pure red cell aplasia (PRCA). We also identified massive infiltration of cytotoxic T-lymphocytes expressing CD8, granzyme B, and perforin in bone marrow. Systemic cyclosporine was started, with full resolution of anemia and no need for blood transfusions after 4 weeks. We believe that this represents the first report of COVID-19-associated PRCA successfully treated using cyclosporine.

Roxadustat Improves Erythropoietin Antibody-Mediated Pure Red Cell Aplasia in a Patient with Hemodialysis.

Anemia is a common complication of chronic kidney disease (CKD). Recombinant human erythropoietin (rHu-EPO) is used extensively in patients with CKD. However, anti-erythropoietin (anti-EPO) antibody has been reported during rHu-EPO treatment, which causes pure red cell aplasia (PRCA). We presented a case of 75-year-old man, who underwent hemodialysis for 2 years. He developed PRCA during rHu-EPO treatment. The rHu-EPO was immediately discontinued, and the patient was given roxadustat treatment. After 6 months of roxadustat treatment, the anti-EPO antibody was disappeared, and hemoglobin recovered normal range. The results suggest that roxadustat can be used to treat patients with anti-EPO antibody-mediated PRCA without immunosuppressive therapy.

Myasthenia Gravis crossing Parkinson's disease: a 20 year study from single Italian center.

PURPOSE: The concomitant diagnosis of Parkinson's disease (PD) and Myasthenia Gravis (MG) is rare. The aim of the study was to report our experience of patients with both diagnoses. MATERIAL AND METHODS: We performed a retrospective analysis of patients with MG and PD, seen at Neurology Department, Modena, Italy from 2000 to 2020. We encountered 12 patients with both diagnoses. All had late onset MG (LOMG) and low Myasthenia Gravis Foundation of America (MGFA) severity scores at baseline. In respect of PD assessement, clinical signs were followed and summarized with modified Hoehn and Yahr staging (mHY). Patients were ranked as progressive or non-progressive, according to any change in mHY staging. We compared characteristics and outcome of the patients with age matched myasthenic subjects without PD. RESULTS: The male gender significantly prevailed (p < 0.01) as well as the presence of multiple comorbidities (p < 0.001) in patients with MG associated with PD. In respect of clinical course, MG was benign as most of cases remained stable (66.7%). Six cases showed worsening of mHY scores; only one subject became wheelchair bound by the end of follow up. This uneven progression, at least in our hands, might suggest that MG and PD can evolve independently. CONCLUSION: Clinicians should be alert about the association of PD and MG since early diagnosis and treatment are essential.

[The efficacy of alemtuzumab for pure red cell aplasia associated with autoimmune polyendocrine syndrome type 1].

We present a case of a 41-year-old woman who was diagnosed with autoimmune polyendocrine syndrome type 1 (APS-1) at the age of 2. She developed severe anemia and was diagnosed with pure red cell aplasia (PRCA) and T-cell large granular lymphocyte leukemia at the age of 34. The pathogenesis of APS-1 is based on the presence of an inactive mutation in the autoimmune regulator gene on thymic medullary epithelial cells. It is thought that the autoimmune T cells generated by impaired negative selection in the thymus induce PRCA. The patient was treated with immunosuppressive therapy (ciclosporin, antithymocyte globulin, prednisolone, and cyclophosphamide) for a long time by her previous doctor. After a long period of remission and exacerbation, she became dependent on blood transfusion approximately at the age of 40 and was transferred to our hospital. At our hospital, alemtuzumab treatment resulted in the disappearance of large granular lymphocytes and improvement of anemia. We report this case as a valuable demonstration of the efficacy of alemtuzumab for treating PRCA associated with APS-1.