Red Cell Aplasia Research Articles

Sars-Cov-2 Infection Associated with Aplastic Anemia and Pure Red Cell Aplasia

Introduction: Aplastic anemia (AA) is a life-threatening disorder characterized by pancytopenia and a hypocellular bone marrow. Pure red cell aplasia (PRCA) is a similar disorder with primary reduction in the red blood cell population and virtual absence of erythroid precursors in the bone marrow. While the etiology of immune mediated marrow failure is multifactorial, preceding viral infections have been associated with the disease; these include parvovirus B19, cytomegalovirus, and Epstein-Barr virus. We present four cases of immune mediated marrow failure with either preceding or simultaneous SARS-CoV-2 infection.Methods: The medical records of patients treated for AA or PRCA at the University of Texas Southwestern Medical Center, Parkland Hospital, and the National Institutes of Health (NIH) were reviewed for SARS-CoV-2 infection. Four patients without prior hematological diseases were identified who had SARS-CoV-2 infection prior to or with simultaneous the diagnosis of AA or PRCA.Results: Patient #1 was a 22-year-old white female who was diagnosed with asymptomatic COVID-19 10 days prior to her pancytopenia and AA diagnosis was confirmed by bone marrow biopsy (5% cellularity; Table 1). Her extensive work-up including HIV, hepatitis panel, immunoglobulins, B12 and folate was negative, and she underwent HLA-matched family donor hematopoietic stem cell transplant. Patient #2 was a 69-year-old Asian female who presented to her primary care physician with symptoms of fatigue and was found to be pancytopenic. CBC from a few months prior was completely normal. Further work-up was positive for COVID-19 and negative for HIV, nutritional deficiency, or hemolysis. She did not have respiratory symptoms, was eventually diagnosed with pRBC and platelet transfusion-dependent severe AA (5-10% cellularity on bone marrow), and underwent treatment with cyclosporine, equine antithymocyte globulin, and eltrombopag. She has had a partial response to this therapy. Both patients had bone marrow specimens stained for SARS-CoV-2 by immunohistochemistry that were negative. Patient #3 was a 76-year-old white male who was diagnosed with COVID-19 4 months prior to presenting with a non-ST segment myocardial infarction and found to be profoundly anemic, requiring pRBC transfusion. He re-presented with chest pain one week later and was found to be anemic again, and required transfusion. A trial of darbepoetin alfa was unsuccessful. Extensive work-up for malignancy, infection, and autoimmune etiologies were negative. He was diagnosed with PRCA based on the bone marrow biopsy and initiated treatment with cyclosporine. Patient # 4 was diagnosed with severe AA (presenting as pancytopenia) and COVID-19 infection. He had fatigue for one month and fever, chills and sore throat one-week prior seeking medical care. Testing for hepatitis, HIV, EBV, and CMV was negative. He was treated on a clinical trial (NCT04304820) at NIH with cyclosporine and eltrombopag until SARS-CoV-2 PCR was negative then received equine anti-thymocyte globulin. He has achieved a complete hematologic response at 6 months and remains well at last follow-up.Conclusion: The four patients described had minimal respiratory COVID-19 symptoms, but they presented with cytopenia and were eventually diagnosed with bone marrow failure. It is possible that this is co-incidental due to the high prevalence of SARS-CoV-2. However, there is emerging evidence that COVID-19 pneumonia is a hyperinflammatory and immune dysregulated state improved by dexamethasone therapy. Other immune mediated hematologic conditions, such as autoimmune hemolytic anemia and immune thrombocytopenia, have been reported. The onset from infection to cytopenia appears rapid, although patients often presented with symptoms for many days prior to diagnosis and thus testing may have been delayed from the onset of infection. This case series does not provide a mechanistic link between SARS-CoV-2 infection and bone marrow failure, but it raises the possibility that SARS-CoV-2 may mediate an immunologic response that contributes to marrow failure. Patients appear to respond well to standard immunosuppressive treatment. Further cases and studies are needed to determine if this is directly linked to SARS-CoV-2 and whether the natural history and response to standard therapy is different than idiopathic cases. [Display omitted] DisclosuresYoung: Novartis: Research Funding.

Immunosuppressive Therapy in Large Granular Lymphocyte Leukemia-Associated Pure Red Cell Aplasia: Cyclophosphamide Responded Better Than Cyclosporine

BackgroundLarge granular lymphocyte leukemia associated pure red cell aplasia (LGLL-PRCA) accounts for a significant portion of secondary PRCA. Cyclosporine (CsA) and cyclophosphamide (CTX) are the main immunosuppressive agents used in treating LGLL-PRCA [1]. Considering the cytotoxicity of CTX, CsA may be proposed as first-line therapy [2]. However, because of the rarity of LGLL-PRCA, long-term responses and relapse rates after CsA and CTX therapy are largely unknown.Methods and resultsFrom September 2009 to December 2020, we selected 65 uniformly diagnosed LGLL-PRCA and analyzed clinical features and treatment outcomes of CsA and CTX.In the present study, 43.1% harbored neutropenia (<1.5×10 9/L) and only 1 patient had spondyloarthritis (Table 1). Besides, we found that 9.2% developed recurrent oral ulcer and 18.5% had reduced serum complemet C3 level, both of which were related to abnormal immune status.In our cohort, 44 patients received CsA therapy and 21 patients received CTX therapy. 53.8% (35/65) obtained erythroid lineage response and 26.2% (17/65) achieved complete response. CTX produced higher response rate (81.0% vs 40.9%, P=0.002) and complete response rate (47.6% vs 15.9%, P=0.007) than CsA. We further analyzed related factors influencing efficacy by Binary-Logistic multivariate regression model and found that higher response rate was mainly related to CTX therapy (P=0.02) (Table 2).We detected STAT3 and STAT5b gene in 50 cases. None of the patients had STAT5b mutation and 14 patients had STAT3 mutation. 12 of 14 mutation cases were non-elderly patients (<60 years ). For younger patients, STAT3 mutation was more frequent (85.7% vs 22.2%, P<0.01). In STAT3 mutation group, patients appeared to respond better to CTX than CsA (83.3% vs 37.5%, P=0.138).Up to the last follow-up, 11 patients treated with CsA recurred after CsA reduction or discontinuation, with a median relapse time of 10 (3~80) months after remission. Only 1 patient relpsed after the discontinuation of CTX due to neutropenia and returned to remission status after CTX retreatment. In our research, CsA had higher recurrence rate than CTX without statistical significance (25.0% vs 4.8%, P=0.104).DiscussionCsA may be proposed as first-line therapy for LGLL-PRCA [2,3]. CTX also appears to be a good treatment choice, but CTX should not be used for more than 12 months since associated toxicities and the risk for developing myelodysplastic syndromes and acute myeloid leukemia. Therefore, it is necessary to compare the efficacy of CsA or CTX in the treatment of LGLL-PRCA.Deep sequencing analyses of residuals LGLL clones reveals that CTX could eradicate LGLL clones, providing durable response, low relapse rate, whereas CsA is associated with the persistence of leukemic clones, and high frequency of relapse [4]. Our results show that the response rate of CTX is higher than CsA (P=0.02), and the probability of recurrence is relatively low (25.0% vs 4.8%, P=0.104). This is consistent with the results of previous study by Rajala [4].It was important to note that patients with STAT3 mutations are more likely to respond to MTX [5]. Our study showed that the response rate for CTX was 83.3% in patients with STAT3 mutations, which was seemingly higher than CsA (37.5%), although remained statistically insignificant (P=0.138) that might be due to small number of cases.ConclusionsThe results of the current study may reflect the real world experience of LGLL-PRCA in whom treated by CTX or CsA, may be limited by its retrospective nature, small cohorts. In preliminary conclusion, LGLL-PRCA could acquired better response to CTX than CsA. Besides, CTX may reduce relapse.

Real World Use of Narsoplimab in a Case of Severe HSCT-TMA

Introduction: Hematopoietic stem cell transplantation (HSCT) offers a curative approach for hematologic malignancies. However, endothelial injury from HSCT activates the lectin pathway of complement, resulting in complications such as thrombotic microangiopathy (TMA). HSCT-TMA causes significant mortality. Incidence is reported up to 39%, although lack of consensus on diagnostic criteria results in under-recognition. Risk factors for HSCT-TMA include calcineurin inhibitors (CNI), conditioning, and infection. There is currently no approved treatment for HSCT-TMA.Narsoplimab is a monoclonal antibody that inhibits MASP-2, the effector enzyme of the lectin pathway. We report a patient with late-onset HSCT-TMA who was successfully treated with narsoplimab via a compassionate use program.Methods and Results: A 60-year-old woman with de novo acute myeloid leukemia t (9;11) (p22; q23) who achieved first complete remission (CR1) with minimal residual disease positivity confirmed by flow cytometry (0.04%) underwent matched related allogeneic HSCT from her sister. Patient was cytomegalovirus (CMV) seropositive and blood group O, whereas donor was CMV seronegative and blood group B. Patient received induction with 7+3 and HiDAC consolidation, achieving CR1. Conditioning regimen was Bu4Flu with graft versus host disease (GVHD) prophylaxis of mini methotrexate and tacrolimus.Letermovir was used for CMV reactivation prophylaxis until Day +100. Post-transplant maintenance therapy with azacitidine 36 mg/m 2 was administered by four 5-day cycles (de Lima Cancer 2010). Patient achieved completed donor myeloid CD33 chimerism at Day +30, but donor lymphoid CD3 chimerism was not complete until Day +239. Tacrolimus was discontinued at Day +180. Patient initially had red cell aplasia but achieved transfusion independence by 6 months post-transplant.Circa achieving complete donor CD3 chimerism, patient developed extensive skin and gastrointestinal-overlap GVHD requiring admission for high-dose steroid therapy and resumption of tacrolimus. Onset of GVHD precluded stopping CNI. Patient became steroid refractory and ruxolitinib was added for immunosuppression with resolution of symptoms.Four weeks later, patient developed CMV reactivation and started induction therapy with valganciclovir, during which time she became red cell-transfusion dependent. Patient required 3 weeks induction and 10 days maintenance to clear CMV viremia.Subsequently, she reported dark red urine with evidence for hemoglobinuria without viruria, bilateral leg edema unresponsive to diuretic therapy, and rising serum lactate dehydrogenase (LDH). Evaluation revealed negative direct antiglobulin test, schistocytes on peripheral blood smear (~5/hpf), elevated sC5b-9 levels of 334 ng/mL (72-244 ng/mL), and elevated random urine protein of 124 mg/dL indicative of end organ damage. LDH was modestly elevated 302 IU/L (84-246 IU/L) and haptoglobin was elevated. Based on clinical symptoms and lab results, she was diagnosed with late-onset HSCT-TMA on Day +282 (9 months) using published diagnostic criteria proposed by Cho (2010) and Jodele (2014).The patient's clinical symptoms worsened with severe leg edema - which impeded her ability to walk - and red cell and platelet transfusion dependency. With no approved therapies, compassionate use of narsoplimab was requested for this clinical course of HSCT-TMA. Treatment commenced on Day +309.Patient received a total of 21 doses of narsoplimab 370 mg administered twice weekly on an outpatient basis. All infusions were well tolerated. No adverse events were noted with narsoplimab. Peripheral counts, LDH, anemia, thrombocytopenia and sC5b-9 normalized with reduction in proteinuria, reflecting resolution of HSCT-TMA by dose 19 (10 weeks of treatment); two additional doses were administered (Figure 1). Narsoplimab was given concomitantly with tacrolimus. Patient became transfusion independent and leg edema resolved.Conclusions: This report presents a real-world case study of HSCT-TMA treated with narsoplimab via compassionate use. HSCT-TMA resolved after 10 weeks of treatment, as evidenced by peripheral counts, normalization of LDH and sC5b-9, reduction in urinary protein reflecting improvement in renal function, and improvement in clinical symptoms. Narsoplimab was effective in this complicated case despite several risk factors for poor outcomes. [Display omitted] DisclosuresPantin: Omeros Corporation: Honoraria. Billy: Omeros Corporation: Current Employment. OffLabel Disclosure:Off-label use of azacitidine for post-transplant maintenance therapy

SATB1 Regulates Chromatin Organization and HSP70 Expression in Early Erythropoiesis and Is Downregulated in Models of Diamond Blackfan Anemia

Diamond Blackfan Anemia (DBA) is a rare genetic disease predominantly caused by mutations carried within one of at least 20 ribosomal genes. DBA is characterized by red blood cell aplasia and normal myeloid and megakaryocyte progenitors, indicating that early uncommitted progenitors are relatively unaffected by the mutations. In DBA, the formation of BFU-E colonies and subsequent erythroblasts are severely restricted and indicate a defect in one of the earliest stages of erythroid expansion.To identify critical molecular mechanisms that may regulate early erythropoiesis, we used shRNAs against the ribosomal protein RPS19 (the most commonly mutated gene in DBA) in cord blood derived CD34+ hematopoietic stem and progenitor cells (HSPCs) and performed bulk RNA-seq. After 3 days in an erythroid culture media, the transcriptomes in CD71+ erythroid progenitors were examined. We found that the special AT binding protein 1 (SATB1) was downregulated in RPS19-insufficient HSPCs compared to healthy cord blood HSPCs.SATB1 is modestly expressed in hematopoietic stem cells but is induced during lymphoid expansion and has been previously reported to suppress myeloid/erythroid progenitor (MEP) expansion. Our results showed that maintaining SATB1 expression is required for optimal expansion of MEP progenitors and that the premature loss of SATB1 in DBA contributes to the anemia phenotype.SATB1 binds to 3 specific regions upstream of the 5'UTR of the HSP70 genes and induces the formation of 2 chromatin loops. An enhancer element associates with the proximal promoters of the two HSP70 genes and facilitates the induction of HSP70. In DBA, HSP70 is not induced and contributes to DBA pathogenesis.HSPA1A is induced 4.3-fold while HSPA1B is induced 3.1-fold. Increased expression of the master erythroid transcription factor GATA1 during erythropoiesis occurs in two phases. The first induction precedes a more dramatic induction that accompanies later stages of erythroid differentiation. The absence of SATB1 or HSP70 reduced the earlier GATA1 induction that accompany MEP expansion by 46.1% and 49.3% respectively. The number of MEPs in SATB1 knockdown HSPCs was reduced, resulting in a 24.5% reduction in CD235+ erythroid and 20.8% reduction in CD41+ megakaryocytes.While SATB1-independent effects of RPS19-insufficiency contribute more significantly to erythroid defects in DBA, we have uncovered that SATB1 contributes to regulation of the earliest stages of erythropoiesis by facilitating the induction of HSP70 and subsequent stabilization of an early induction of GATA1. DisclosuresNo relevant conflicts of interest to declare.

Vitamin A and D Levels Correlate with Outcomes Following Acute Parvovirus B19 Infection in Children with Sickle Cell Disease

Background: Human parvovirus B19, a common childhood infection that typically causes mild disease in healthy individuals, causes life-threatening anemia due to transient red cell aplasia (aplastic crisis) in individuals with sickle cell disease (SCD). This complication often leads to hospitalization and red blood cell transfusions. Limiting the amount of transfusions is imperative to avoid alloimmunization. Strategies to mitigate complications from parvovirus B19 or reduce disease severity in SCD patients are needed. In this prospective observational study, we aim to describe the relationship between vitamin A and D levels and severity of symptoms during parvovirus B19 infection in pediatric patients with SCD.Methods: Twenty pediatric patients with SCD admitted to St. Jude Children's Research Hospital experiencing aplastic crisis and identified as having an active parvovirus B19 infection were under an IRB approved protocol (NCT02261480) and followed prospectively for 120 days post-infection. Acute parvovirus B19 infection was diagnosed by fever and a positive virus-specific IgM ELISA or PCR. Aplastic crisis was defined by worsened anemia without sufficient compensatory reticulocytosis in the setting of an acute parvovirus B19 infection. Virus-specific antibody responses were measured from sera or nasal washes (NW) by ELISA using parvovirus B19 virus-like particles (VLP) as target antigens. Peak serum antibody titers were defined (among measurements from Days 0, 7, 30, and 120). Total erythrocyte transfusion volumes required during the admission were quantified. Hematologic indices and vitamin A and D levels were obtained on Day 0. Vitamin A (retinol) was measured using UPLC and vitamin D (25[OH]D) was measured using a Roche Elecsys Vitamin D ELISA. Statistical analyses were performed with Spearman's rank correlation coefficient or Mann Whitney tests. We scored significance as p<0.05.Results: Twenty patients with different genotypes of SCD requiring hospital admission due to acute parvovirus B19 infection were sequentially enrolled (15 HbSS, 3 HbSC, 1 HbSD, 1 HbSβeta +thalassemia). Thirty-five percent (7/20) of patients were vitamin D deficient (VDD, defined here as <20 ng/mL) while 89% (17/19, one sample was not measured) of patients were marginally or severely vitamin A deficient (defined here as <20 μg/dL) on Day 0. Correlative analyses between vitamin levels and markers of disease severity are shown in figure 1. Lower vitamin D levels trended with lower hemoglobin (r=0.399, p=0.082) and there was a significant inverse correlation between transfused volume and vitamin D levels (r=-0.626, p=0.003, Figure 1B). There was a significant positive correlation of vitamin A levels on Day 0 with hemoglobin concentration (r=0.549, p=0.015, Figure 1D), and an inverse correlation between vitamin A levels and lactate dehydrogenase (r=-0.505, p=0.027, Figure 1F).Children with replete vitamin D levels exhibited significantly better peak virus-specific serum IgG (p=0.037) and IgA (p=0.011) responses (Figure 2A-B). Additionally, vitamin A, which plays an important role in mucosal immunity, correlated positively with virus-specific IgG (r=0.574, p=0.013) and IgA (r=0.480, p=0.044) in nasal passages on Day 30 (Figure 2C-D).Conclusions: In pediatric patients admitted to the hospital for acute parvovirus B19 infection, low vitamin A and D levels were associated with greater disease severity (greater hemolysis, lower hemoglobin concentration, and greater transfusion volumes). Higher vitamin levels were associated with better virus-specific antibody responses. While cause-effect relationships were not discerned in this study, we hypothesize that poor nutritional status contributed to poor outcomes and that efforts to improve nutrition may reduce the severity of parvovirus B19 disease in patients with SCD. [Display omitted] DisclosuresHankins: UpToDate: Consultancy; Vindico Medical Education: Consultancy; Global Blood Therapeutics: Consultancy; Bluebird Bio: Consultancy.

PURE RED CELL APLASIA : A CASE REPORT

Pure cell aplasia is a rare bone marrow failure that affects erythroid lineage characterized by normocytic normochromic anemia with reticulocytopenia in the peripheral blood and absent or infrequent erythroblasts in the bone marrow. It can be congenital or acquired. Acquired can be primary when no cause is identied or secondary-due to underlying or associated pathology. Herein we report a case of a 28 year old female with Primary Acquired Pure Red cell aplasia. The patient presented with severe anemia (Hb-1.9gm%) and low reticulocyte count 0.1%. Bone marrow aspiration shows normocellular marrow with Decreased erythropoiesis with M:E ratio of 20:1..Patient was started on oral prednisolone and improvement was seen and the patient became transfusion independent.

Evaluation of the efficacy and safety of recombined human erythropoietin combined with cyclosporin A in the treatment of patients with pure red cell aplasia

Evaluation of the efficacy and safety of recombined human erythropoietin combined with cyclosporin A in the treatment of patients with pure red cell aplasia

A Boy with X-Linked Inhibitor of Apoptosis Protein (XIAP) Deficiency as the Initial Presentation of Pure Red Cell Aplasia

A Boy with X-Linked Inhibitor of Apoptosis Protein (XIAP) Deficiency as the Initial Presentation of Pure Red Cell Aplasia

Anti Thymocyte Globulin-Based Treatment for Acquired Bone Marrow Failure in Adults.

Idiopathic acquired aplastic anemia can be successfully treated with Anti Thymocyte Globulin (ATG)-based immune suppressive therapy and is therefore considered a T cell-mediated auto immune disease. Based on this finding, several other forms of idiopathic acquired bone marrow failure are treated with ATG as well. For this review, we extensively searched the present literature for evidence that ATG can lead to enduring remissions in different forms of acquired multi- or single-lineage bone marrow failure. We conclude that ATG-based therapy can lead to an enduring hematopoietic response and increased overall survival (OS) in patients with acquired aplastic aplasia. In patients with hypocellular myelodysplastic syndrome, ATG can lead to a hematological improvement without changing the OS. ATG seems less effective in acquired single-lineage failure diseases like Pure Red Cell Aplasia, Amegakaryocytic Thrombocytopenia and Pure White Cell Aplasia, suggesting a different pathogenesis in these bone marrow failure states compared to aplastic anemia. T cell depletion is hypothesized to play an important role in the beneficial effect of ATG but, as ATG is a mixture of polyclonal antibodies binding to different antigens, other anti-inflammatory or immunomodulatory effects could play a role as well.

The Glucocorticoid Receptor Polymorphism Landscape in Patients With Diamond Blackfan Anemia Reveals an Association Between Two Clinically Relevant Single Nucleotide Polymorphisms and Time to Diagnosis.

NR3C1, the gene encoding the glucocorticoid receptor, is polymorphic presenting numerous single nucleotide polymorphisms (SNPs) some of which are emerging as leading cause in the variability of manifestation and/or response to glucocorticoids in human diseases. Since 60–80% of patients with Diamond Blackfan anemia (DBA), an inherited pure red cell aplasia induced by mutations in ribosomal protein genes became transfusion independent upon treatment with glucocorticoids, we investigated whether clinically relevant NR3C1 SNPs are associated with disease manifestation in DBA. The eight SNPs rs10482605, rs10482616, rs7701443, rs6189/rs6190, rs860457, rs6198, rs6196, and rs33388/rs33389 were investigated in a cohort of 91 European DBA patients. Results were compared with those observed in healthy volunteers (n=37) or present in public genome databases of Italian and European populations. Although, cases vs. control analyses suggest that the frequency of some of the minor alleles is significantly altered in DBA patients with respect to healthy controls or to the Italian or other European registries, lack of consistency among the associations across different sets suggests that overall the frequency of these SNPs in DBA is not different from that of the general population. Demographic data (47 females and 31 males) and driver mutations (44 S and 29 L genes and eight no-known mutation) are known for 81 patients while glucocorticoid response is known, respectively, for 81 (36 responsive and 45 non-responsive) and age of disease onsets for 79 (55 before and 24 after 4months of age) patients. Neither gender nor leading mutations were associated with the minor alleles or with disease manifestation. In addition, none of the SNPs met the threshold in the response vs. non-responsive groups. However, two SNPs (rs6196 and rs860457) were enriched in patients manifesting the disease before 4months of age. Although the exact biomechanistical consequences of these SNPs are unknown, the fact that their configuration is consistent with that of regulatory regions suggests that they regulate changes in glucocorticoid response during ontogeny. This hypothesis was supported by phosphoproteomic profiling of erythroid cells expanded ex vivo indicating that glucocorticoids activate a ribosomal signature in cells from cord blood but not in those from adult blood, possibly providing a compensatory mechanism to the driving mutations observed in DBA before birth.

Large Granular Lymphocyte Expansion in Myeloid Diseases and Bone Marrow Failure Syndromes: Whoever Seeks Finds.

Large granular lymphocytes (LGL) are lymphoid cells characterized by either a T-cell or a natural killer phenotype whose expansion may be reactive to toxic, infectious, and neoplastic conditions, or result from clonal selection. Recently, the higher attention to LGL clones led to their detection in many clinical conditions including myeloid neoplasms and bone marrow failures. In these contexts, it is still unclear whether LGL cells actively contribute to anti-stem cell autoimmunity or are only a reaction to dysplastic/leukemic myelopoiesis. Moreover, some evidence exists about a common clonal origin of LGL and myeloid clones, including the detection of STAT3 mutations, typical of LGL, in myeloid precursors from myelodysplastic patients. In this article we reviewed available literature regarding the association of LGL clones with myeloid neoplasms (myelodysplastic syndromes, myeloproliferative neoplasms, and acute myeloid leukemias) and bone marrow failures (aplastic anemia and pure red cell aplasia, PRCA) focusing on evidence of pathogenic, clinical, and prognostic relevance. It emerged that LGL clones may be found in up to one third of patients, particularly those with PRCA, and are associated with a more cytopenic phenotype and good response to immunosuppression. Pathogenically, LGL clones seem to expand after myeloid therapies, whilst immunosuppression leading to LGL depletion may favor leukemic escape and thus requires caution.

Research Progress on Pathogenesis of Congenital Pure Red Cell Aplasia---Review

Congenital pure red cell aplasia, also known as Diamond-Blackfan anemia (DBA), is a hereditary disease characterized by pure red cell aplasia and congenital malformation. Its main clinical features are anemia, dysplasia, and tumor susceptibility. Ribosomal protein (RP) gene mutation is the main pathogenesis of DBA. The most common type of gene mutation is RPS19 gene mutation. Heterozygous mutations in as many as 19 RP genes and other non-RP genes mutations have been identified in DBA. This review summarized briedfly the latest research advances in the pathogenesis of DBA.

COMPLICATIONS IN ABO-INCOMPATIBLE HEMATOPOIETIC STEM CELL TRANSPLANT IN PAKISTAN

Background: Hematopoietic stem cell transplantation (HSCT) is therapeutic option for many blood diseases. It has increased risk of complications with incompatible pair. The objective of this study was to determine the frequency of complications in ABO-incompatible HSCT in Pakistan.Materials Methods: This cross-sectional study was conducted at Armed Forces Bone Marrow Transplant Centre , Rawalpindi, Pakistan from 11th August 2018 till 15th March 2021. A sample of 73 ABO-incompatible HSCT patients was selected. Variables were sex, age groups, acute delayed hemolysis, pure red cell aplasia and acute GvHD. All variables being categorical were described by count and percentage with 80%CI. Complications in sample vs. population were compared through chi-square goodness of fit test.RESULTS: Seventy three patients with ABO-incompatible HSCT included 52 (71.23%) men 21 (28.77%) women, and 49 (67.12%) in age group ≤14 years 24 (32.88%) in ≥15 years. Out of 73 patients, eight (10.96%) had acute hemolysis, 26 (35.62%) had delayed hemolysis, four (5.84%) had pure red cell aplasia and 34 (46.58%) had acute GvHD. The observed prevalence in sample was similar to population for acute (p=.46893) and delayed hemolysis (p=.30759) and acute GvHD (p=.55841), while it was different for pure red cell aplasia (p=.00006).CONCLUSION: Most common complication in our study was acute GvHD, followed by delayed hemolysis, acute hemolysis pure red cell aplasia. The observed prevalence in sample was similar to population for acute delayed hemolysis and acute GvHD, while it was different for pure red cell aplasia.

Les tumeurs thymiques: Thymic tumors

Thymic epithelial tumors are rare malignancies, that may be aggressive and difficult to treat, with variable prognosis. The histopathological classification distinguishes two major tumor types: thymomas, which reproduce the architecture of the normal thymus, combining thymic epithelial tumor cells, and non-tumoral lymphocytes, and thymic carcinomas. Autoimmune manifestations are observed in nearly one third of patients at diagnosis; myasthenia gravis is the most common, followed by pure red cell aplasia and hypogammaglobulinemia. The historical staging system is the Masaoka system, reviewed by Koga; the TNM system is standard since 2018.Assessing the resectability of the tumor represents the first stage of the therapeutic strategy, as complete resection is the most significant prognostic factor on patient survival. If complete resection seems possible upfront, surgery is the first step of the treatment, and is possibly followed by postoperative radiotherapy. For unresectable thymic tumors, pre-treatment biopsy is performed, and treatment is then based on induction chemotherapy followed by surgical resection or radiotherapy. Patients with no eligibility to focal treatment receive chemotherapy alone.Following a call of the French National Cancer Institute, a network of expert centers for the management of thymic malignancies started in in 2012: RYTHMIC. More than 3 000 patients have been discussed at RYTHMIC multidisciplinary tumor board.© 2021 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Recommendations on hematopoietic stem cell transplantation for patients with Diamond-Blackfan anemia. On behalf of the Pediatric Diseases and Severe Aplastic Anemia Working Parties of the EBMT.

Diamond Blackfan anemia (DBA) is a rare congenital syndrome presenting primarily as pure red cell aplasia with constitutional abnormalities and cancer predisposition. Established treatment options are corticosteroids, regular erythrocyte transfusions with iron chelation therapy, and hematopoietic stem cell transplantation (HSCT). To date, HSCT is the only definitive curative treatment for the hematological phenotype of DBA, but there is little experience with its use. Given the rarity of the disease and its unique features, an expert panel agreed to draw up a set of recommendations on the use of HSCT in DBA to guide clinical decision-making and practice. The recommendations address indications, pretransplant patient evaluation, donor selection, stem cell sources, conditioning regimens, prophylaxis of rejection and graft versus host disease, and post-transplant follow-up.

A case series of emtricitabine-induced pure red cell aplasia.

BackgroundAnaemia is common in patients with retroviral disease. New or worsening anaemia after initiation of antiretroviral (ARV) treatment has a broad differential diagnosis.ObjectivesWe describe six patients who developed transfusion-dependent anaemia on first-line therapy (tenofovir, emtricitabine and efavirenz) and, by exclusion, implicated emtricitabine in the aetiology of the anaemia.MethodWe conducted a retrospective chart review of patients seen at the Infectious Diseases specialist clinic at King Edward VIII Hospital in KwaZulu-Natal between 2014 and 2016. We focused on patients with isolated, refractory and transfusion-dependent anaemia occurring after initiation of ARVs, in whom bone marrow biopsies were consistent with pure red cell aplasia (PRCA) without an identifiable secondary cause.ResultsAll the patients were female, with a median (range) age and baseline CD4 cell count of 42.5 (23–61) years and 237 (83–329) cells/mm3, respectively. Before presenting with symptomatic anaemia, the duration on emtricitabine was 4.5 (2–8) months. At presentation, all patients had an HIV viral load of < 1000 copies/mL and a CD4 cell count of 314 (213–389) cells/mm3. The median time to recovery following the discontinuation of emtricitabine was 2 (1–4) months. After a median of 12 months, all patients were successfully rechallenged with emtricitabine and remained well for a follow-up period of 24 (7–36) months.ConclusionThis study provides strong circumstantial evidence that emtricitabine plays an important role in the pathogenesis of reversible PRCA. The mechanisms through which emtricitabine induces PRCA remain unclear and require further study.

Indications and diagnostic value of bone marrow examination in HIV-positive individuals: A 3-year review at Tygerberg Hospital.

BackgroundBone marrow examination is a useful diagnostic tool in human immunodeficiency virus (HIV)-positive patients presenting with cytopenias and fever. However, its role in the afebrile and asymptomatic patient presenting with an isolated cytopenia is not well established. This study was conducted to determine the indications for bone marrow examination and its diagnostic yield, in HIV-positive patients at Tygerberg Hospital.MethodsA retrospective, cross-sectional descriptive study was performed over a 3-year period from 01 September 2015 to 31 August 2018. The bone marrow examination reports for the HIV-positive patients who had a bone marrow examination during the study period were retrieved. Clinical and laboratory information was captured.ResultsAltogether 374 bone marrow reports for HIV-positive patients were found. The indication of the bone marrow examination included investigation of unexplained cytopenias, suspected haematological malignancies, follow-up examination for patients with known haematological diseases, staging of haematological or non-haematological malignancies and investigation of suspected disseminated infection. The patients’ median age was 43 years and the interquartile range was 27–60 years. There was a slight female predominance with females 51% and males 49%. The diagnostic yield was 33.7%. Acute leukaemia and lymphoma were the most common diagnoses. Haematinic deficiency and pure red cell aplasia were found in the majority of cases with isolated anaemia. All cases with isolated thrombocytopenia were due to immune thrombocytopenia.ConclusionBone marrow examination is a useful investigation for HIV-positive patients with cytopenias, suspected haematological malignancy and lymphoma staging. However, its early use in patients with isolated anaemia and isolated thrombocytopenia is questionable.

Marrow aplasia congenital red series: Diamond Blackfan Anemia. About a case

Pure red cell aplasia medullary is a disorder characterized by anemia with almost complete absence of red cell precursors in the bone marrow, with leukocyte count and platelets. The Diamond-Blackfan anemia is a failure syndrome characterized by bone marrow anemia, reticulocytopenia and decreased erythroid precursors in the bone marrow. the case of an infant under 2 months of age presented no family or perinatal history major, whose mother progressive skin pallor evidence mucosa associated with hyporexia; go to health center where they perform paraclinical reporting hemoglobin 1.7 g / dL. peripheral blood smear where erythroid frankly affected with normal megakaryocytic granulocytic count shown is made; It biopsied and bone marrow aspirate concluding marrow red cell aplasia; possible anemia Diamond-Blackfan in light of other clinical findings arises. It stays with glucocorticoid treatment, however insufficient response, begins erythropoietin dose progressively increasing, despite it, warrants blood transfusions on a regular basis; compatibility studies performed with first-degree resulting positive, currently a candidate for allogeneic bone marrow transplantation. It is concluded that despite being a rare syndrome should be suspected in severe anemia where there is acute blood loss, ruling out other etiologies; also timely initiation of treatment is critical to the survival of these patients.

Pure Red Cell Aplasia in Systemic Lupus Erythematosus, a Nationwide Retrospective Cohort and Review of the Literature

Objectives To characterize the clinical and biological course, management and response to treatment in Systemic Lupus Erythematosus (SLE)-associated Pure Red Cell Aplasia (PRCA). Methods Nationwide multicentre retrospective cohort study. From 2006 to 2018, we included adults with a diagnosis of PRCA supported by bone-marrow examination and SLE or biologic manifestations of SLE after ruling out parvovirus B19 infection. Results We enrolled 24 patients (20 women). SLE was diagnosed before PRCA for 14 patients (median delay 81 months). At PRCA diagnosis, mean age, haemoglobin level and reticulocyte and differential erythroblast count were 39.2 ± 13.2 years, 62 ± 20 g/L, 9.1 ± 7.6 x 109/L and 2.8 ± 2.5%, respectively. Eleven (45%) patients experienced multiple PRCA flares (median 6, range: 2-11). Corticosteroid therapy resulted in only three complete sustained responses, and 19 (79%) patients required immunosuppressive agents with highly variable regimens. After a median follow-up of 76 months (range 13-173), 17 (71%) patients showed complete response for PRCA, five (21%) partial response and two (8%) treatment failure. In total, 21 (87%) patients required red-blood-cell transfusion; five had a diagnosis of transfusion-related iron overload. Eighteen (75%) patients experienced severe infectious events requiring hospitalization. Conclusion SLE-associated PRCA is a severe condition. Repeated red-blood-cell transfusions and several lines of immunosuppressant therapy are mostly required with high risk of severe infectious events and iron overload. Despite sustained response for PRCA and SLE obtained in most patients, the best therapeutic strategy remains to be determined.

Exploring the Rare Etiology of Severe Anemia in an Immunocompromised Patient

Pure red cell aplasia (PRCA) is a rare cause of profound anemia, marked by very low reticulocyte count and near to complete absence of erythroid precursor cells in the bone marrow. PRCA can be congenital such as in the case of children with Diamond- Blackfan anemia or acquired, which is often triggered by exposure to certain viruses or drugs. Management depends on the underlying etiology of PRCA. Here, we present the case of a young male with underlying acquired immunodeficiency syndrome, who presented with a hemoglobin of 2.6 g/dL, initially thought to be secondary to gastrointestinal blood loss, but was later discovered to have parvovirus-induced PRCA.