Different clinical courses with the same findings: two cases of paroxysmal nocturnal hemoglobinuria presenting with thrombocytopenia

Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal stem cell disease that manifests with chronic intravascular hemolysis, thrombosis, and bone marrow failure. Various degrees of cytopenias accompany the disease. Although laboratory and clinical findings are similar, the disease may show different courses and require different treatments. Herein, we report two different courses of PNH with similar clinical and laboratory findings.

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Erythrocytosis after Allogeneic Bone Marrow Transplantation in the Patients with Severe Aplastic Anemia.

Blood ◽

10.1182/blood.v108.11.5327.5327 ◽

2006 ◽

Vol 108 (11) ◽

pp. 5327-5327

Author(s):

Soo-Jeong Park ◽

Chi-Wha Han

Keyword(s):

Bone Marrow ◽

Stem Cell ◽

Aplastic Anemia ◽

Bone Marrow Failure ◽

Allogeneic Bone Marrow Transplantation ◽

Severe Aplastic Anemia ◽

Allogeneic Bone ◽

Laboratory Findings ◽

Normal Ranges ◽

Serum Erythropoietin Level

Abstract Severe aplastic anemia (sAA) is a bone marrow failure disorder which is mostly a consequence of immunologically mediated stem cell destruction. Stem cell transplantation (SCT) from a histocompatible sibling is a treatment of choice for this disease but major obstacles in success of allogeneic SCT include graft-versus-host disease (GVHD), graft rejection and treatment related toxicities. We describe two cases of post-transplant erythrocytosis in severe aplastic anemia. About 5 years later, following HLA-matched sibling transplantation, the patients (45-year-old male and 43-year-old male) developed a sustained increase in hemoglobin (>17 g/dL) and hematocrit (> 50%), an increase in the frequency of headache, and new onset of dizziness and malaise. Laboratory findings demonstrated normal ranges of other blood components and serum erythropoietin level, and they did not have smoking or other drugs. Also, they did not have a hepatosplenomegaly or other organ diseases. We initiated a therapeutic phlebotomy program (400 ml q 2–4 weeks and then q 2–3 months for 5 years) in order to lower the hematocrit to available values (Hb < 14.5 g/dL), and to induce iron deficiency (Fig 1). Repeated phlebotomy resulted in a decrease in symptoms and a total volume of blood venesection is about 9,200 – 11,200 ml so far. Figure 1. Hemoglobin change after bone marrow transplantations. Figure 1. Hemoglobin change after bone marrow transplantations.

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DNA Microarray Analysis of GPI-Negative Hematopoietic Stem Cells in Paroxysmal Nocturnal Hemoglobinuria Patients.

Blood ◽

10.1182/blood.v106.11.1048.1048 ◽

2005 ◽

Vol 106 (11) ◽

pp. 1048-1048

Author(s):

Kazuhiko Ikeda ◽

Tsutomu Shichishima ◽

Yoshihiro Yamashita ◽

Yukio Maruyama ◽

Hiroyuki Mano

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Stem Cell ◽

Hematopoietic Stem Cells ◽

Hematopoietic Stem Cell ◽

Paroxysmal Nocturnal Hemoglobinuria ◽

Bone Marrow Failure ◽

Data Set ◽

Hematopoietic Stem ◽

Pnh Clone

Abstract Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal hematological disorder which is manifested by complement-mediated hemolysis, venous thrombosis, and bone marrow failure. Deficiencies of glycosylphosphatidylinositol (GPI)-anchored proteins, due to mutations in the phosphatidylinositol glycan-class A (PIG-A) gene, contribute to complement-mediated hemolysis and affect all hematopoietic lineages in PNH. However, it is unclear how a PNH clone with a PIG-A gene mutation expands in bone marrow. Although some genes, including the Wilms’ tumor gene (Shichishima et al, Blood, 2002), the early growth response gene, anti-apoptosis genes, and the gene localized at breakpoints of chromosome 12, have been reported as candidate genes that may associate with proliferations of a GPI-negative PNH clone, previous studies were not intended for hematopoietic stem cell, indicating that the differences in gene expressions between GPI-negative PNH clones and GPI-positive cells from PNH patients remain unclear at the level of hematopoietic stem cell. To identify genes contributing to the expansion of a PNH clone, here we compared the gene expression profiles between GPI-negative and GPI-positive fractions among AC133-positive hematopoietic stem cells (HSCs). By using the FACSVantage (Becton Dickinson, San Jose, CA) cell sorting system, both of CD59+AC133+ and CD59− AC133+ cells were purified from bone marrow mononuclear cells obtained from 11 individuals with PNH. Total RNA was isolated from each specimen with the use of RNeasy Mini column (Qiagen, Valencia, CA). The mRNA fractions were amplified, and were used to generate biotin-labeled cDNAs by the Ovation Biotin system (NuGEN Technologies, San Carlos, CA). The resultant cDNAs were hybridized with a high-density oligonucleotide microarray (HGU133A; Affymetrix, Santa Clara, CA). A total of >22,000 probe sets (corresponding to >14,000 human genes) were assayed in each experiment, and thier expression intensities were analyzed by GeneSpring 7.0 software (Silicon Genetics, Redwood, CA). Comparison between CD59-negative and CD59-positive HSCs has identified a number of genes, expression level of which was statistically different (t-test, P <0.001) between the two fractions. Interestingly, one of the CD59− -specific genes isolated in our data set turned out to encode a key component of the proteasome complex. On the other hand, a set of transcriptional factors were specifically silenced in the CD59− HSCs. These data indicate that affected CD59-negative stem cells have a specific molecular signature which is distinct from that for the differentiation level-matched normal HSCs. Our data should pave a way toward the molecular understanding of PNH.

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A Spontaneous Reduction of Clone Size in Paroxysmal Nocturnal Hemoglobinuria Patients Treated with Eculizumab for Greater Than 12 Months.

Blood ◽

10.1182/blood.v114.22.1992.1992 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1992-1992 ◽

Cited By ~ 4

Author(s):

Richard Kelly ◽

Stephen Richards ◽

Louise Arnold ◽

Gemma Valters ◽

Matthew Cullen ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Maintenance Dose ◽

Paroxysmal Nocturnal Hemoglobinuria ◽

Bone Marrow Failure ◽

Hemopoietic Stem Cells ◽

Intravascular Hemolysis ◽

Complement Protein ◽

Clone Size ◽

Pnh Clone

Abstract Abstract 1992 Poster Board I-1014 Paroxysmal Nocturnal Hemoglobinuria (PNH) is an acquired clonal disorder of hemopoietic stem cells that is characterized by bone marrow failure, intravascular hemolysis and venous thrombosis. Eculizumab is a humanized monoclonal antibody that specifically binds to the complement protein C5 preventing its cleavage thereby inhibiting the formation of the terminal components of the complement cascade. Eculizumab was approved by the FDA in 2007 after clinical trials showed it was efficacious in treating patients with hemolytic PNH. Prior to eculizumab therapy treatment options were mainly supportive in nature. Historical data shows that a third of patients who survive greater than 10 years undergo spontaneous recovery. We present data on 38 patients with hemolytic PNH treated at a single centre with eculizumab for 12 months or longer. Thirty six of these patients were treated with a loading dose of 600mg every week for 4 doses followed by 900mg the following week and then a maintenance dose of 900mg dose every 14 day. The other 2 patients required a higher maintenance dose of eculizumab, 1200mg every 14 days, due to symptomatic intravascular hemolysis on the standard regime. All our patients had a high PNH granulocyte clone size at the initiation of eculizumab treatment from 52.90% to 99.95% with a median of 96.38%. The duration of eculizumab therapy varied from 12 to 84 months with a median treatment duration of 50 months. Granulocyte clone size was used as it is not subject to as much variation as the erythrocyte clone size which changes both due to blood transfusions and to the extent of intravascular hemolysis present. The proportion of PNH granulocytes probably most accurately reflects the true size of the PNH clone. Seven out of these 38 patients (18.4%) have had a 10% or greater reduction in their granulocyte clone size during the course of their eculizumab treatment. These patients have had a steady and continued decline in their granulocyte clone size throughout their treatment with eculizumab. This may actually be due to an increase in the residual normal cells in some patients (see Table). Two of these patients (U.P.N. 5 and 7) have had such a dramatic reduction in their clone size that they have been able to stop their eculizumab treatment without any observed detriment to their health.TableChange in PNH clones in patients on eculizumabU.P.N.Months on eculizumabNeutrophils PNH clone size (%)Normal neutrophils (%)Pre-treatmentMost recent on treatmentPre-treatmentMost recent on treatment15097.242.82.85724878.063.222.036.335596.484.13.615.941592.577.07.523.051261.732.438.367.664788.362.511.737.578552.98.547.191.5 Two of these 7 patients were treated with ciclosporin for underlying aplasia as compared to 3 of the 31 of those who haven't had a decrease in their clone size. There was no difference in the white cell or platelet count in these 7 patients from when they started eculizumab treatment to the present day indicating that the degree of bone marrow failure present has not changed dramatically during this time course. 5 of the 7 patients had neutrophil clone sizes of less than the median perhaps indicating that recovery requires a certain number of residual normal stem cells to be present. There were no other observed differences to distinguish between patients whose clone size fell and those that did not. It is unlikely that eculizumab has a direct effect on clone size in hemolytic PNH. A more probable hypothesis is that the immune selection in favour of the PNH clone expires over time allowing normal hemopoietic stem cells to repopulate the bone marrow. Whether eculizumab has any influence on this rather than just allowing patients to survive and remain well until recovery occurs is not clear. Our data suggests that there needs to be some normal hematopoietic activity in order for the normal marrow cells to expand and clone size under 95% predicts for recovery. In conclusion, a significant minority of patients with PNH on eculizumab have a progressive reduction in the size of their PNH clone during therapy and in some of these patients the clone falls to a level at which eculizumab can safely be stopped. Disclosures: Kelly: Alexion Pharmaceuticals: Honoraria. Richards:Alexion Pharmaceuticals: Honoraria. Hill:Alexion: Honoraria. Hillmen:Alexion Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

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Paroxysmal Nocturnal Hemoglobinuria: Stem Cells and Clonality

Hematology ◽

10.1182/asheducation-2008.1.111 ◽

2008 ◽

Vol 2008 (1) ◽

pp. 111-115 ◽

Cited By ~ 23

Author(s):

Robert A. Brodsky

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Hematopoietic Stem Cell ◽

Paroxysmal Nocturnal Hemoglobinuria ◽

De Novo ◽

Bone Marrow Failure ◽

Cell Disease ◽

Intrinsic Resistance ◽

Hematopoietic Stem ◽

Immune Attack

AbstractParoxysmal nocturnal hemoglobinuria is a clonal hematopoietic stem cell disease that manifests with intravascular hemolysis, bone marrow failure, thrombosis, and smooth muscle dystonias. The disease can arise de novo or in the setting of acquired aplastic anemia. All PNH patients to date have been shown to harbor PIG-A mutations; the product of this gene is required for the synthesis of glycosylphosphatidylinositol (GPI) anchored proteins. In PNH patients, PIG-A mutations arise from a multipotent hematopoietic stem cell. Interestingly, PIG-A mutations can also be found in the peripheral blood of most healthy controls; however, these mutations arise from progenitor cells rather than multipotent hematopoietic stem cells and do not propagate the disease. The mechanism of whereby PNH stem cells achieve clonal dominance remains unclear. The leading hypotheses to explain clonal outgrowth in PNH are: 1) PNH cells evade immune attack possibly, because of an absent cell surface GPI-AP that is the target of the immune attack; 2) The PIG-A mutation confers an intrinsic resistance to apoptosis that becomes more conspicuous when the marrow is under immune attack; and 3) A second mutation occurs in the PNH clone to give it an intrinsic survival advantage. These hypotheses may not be mutually exclusive, since data in support of all three models have been generated.

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Aplastic Anemia in the Context of Hemolytic Paroxysmal Nocturnal Hemoglobinuria: Feasibility of Antibody-Based Intensive Immunosuppression during Eculizumab Treatment

Blood ◽

10.1182/blood.v128.22.5074.5074 ◽

2016 ◽

Vol 128 (22) ◽

pp. 5074-5074

Author(s):

Simona Pagliuca ◽

Flore Sicre de Fontbrune ◽

Serena Marotta ◽

Anna Paola Iori ◽

Marie Robin ◽

...

Keyword(s):

Bone Marrow ◽

Research Funding ◽

Paroxysmal Nocturnal Hemoglobinuria ◽

Standard Dose ◽

Bone Marrow Failure ◽

Prospective Trial ◽

Specific Treatment ◽

Intravascular Hemolysis ◽

Lymphocyte Depletion ◽

Hematological Response

Abstract Paroxysmal nocturnal hemoglobinuria (PNH) may present as hemolytic (classical PNH) or aplastic (AA/PNH syndrome) PNH. While classical PNH patients requires anti-complement treatment (eculizumab), the treatment of AA/PNH patients should target their bone marrow failure (BMF) by immunosuppression (IST), or even bone marrow transplantation (BMT). However, in a few patients clinically meaningful AA and hemolysis may be concomitant, eventually justifying both IST and eculizumab. To date there is no standard treatment for this rare condition. Here we investigated the prevalence of this condition based on a large cohort of PNH patients seen at our reference centers at St. Louis Hospital (Paris) and Federico II University (Naples), looking for patients who have received "intensive IST" in combination with eculizumab. Amongst a total of 145 PNH patients seen between 2007 and 2016, we have identified 6 patients who have received intensive IST during eculizumab treatment ; thus, roughly the prevalence of severe BMF associated with hemolysis is around 5%. All the 6 patients have been initially classified as AA/PNH syndrome at time of eculizumab starting, but did not require specific treatment before; they were all on eculizumab treatment at the standard dose of 900 mg fortnightly, with adequate control of intravascular hemolysis. Five of the patients fulfilled the criteria of severe AA, the latter had very severe isolated neutropenia, and was diagnosed with an immune-mediated agranulocytosis. Since no patient had a HLA-matched related donor for BMT, all the patients received intensive IST according to different institutional regimens; eculizumab was not discontinued to minimize the risk of rebound intravascular hemolysis and thrombotic complications. Three patients (2 AA and 1 agranulocytosis) received standard IST with horse-antithymocyte globulin (h-ATG, 40 mg/kg for 4 consecutive days) combined cyclosporine A (CsA). The 3 other AA patients received alemtuzumab (3-10-30-30 mg subcutaneously in 4 consecutive days) and CsA within the prospective trial NCT00895739; one of these patients a few months later also received a second IST course with rabbit-ATG (3.5 mg/kg for 5 consecutive days) and CsA. All the patients completed the scheduled treatment without any side effect, including infusion-related reactions. Lymphocyte depletion was observed in all patients irrespective of sustained therapeutic complement blockade, with lymphocyte count dropping <100/μL in all cases and lasting for several days (or even months in the case of alemtuzumab). All patients remained on eculizumab treatment, even if one AA patient required an increase of the dose up to 1200 mg because of pharmacokinetic breakthrough; in 2 patients 50% hemolytic complement (CH50) was systematically monitored during the treatment course, without showing any significant change from status at pre-IST treatment. All the patients were available for response assessment at 6 months; globally, 3 out of 6 showed a hematological response. The agranulocytosis patient achieved a partial response (PR) requiring G-CSF chronic treatment. Among the 5 AA patients, we observed 2 CR (1 with h-ATG and 1 with alemtuzumab) and 1 PR (after alemtuzumab); this latter was converted into a CR after a second IST course with r-ATG. One of the CR relapsed at 3 years showing clonal evolution toward a myelodysplastic syndrome, and finally died. All the other patients are alive, keeping their hematological response; of the 3 non-responders, 1 was rescued with an unrelated transplantation, and 2 remain on eculizumab treatment (one has developed thromboembolic complications). This is the first systematic description of the management of severe BMF in PNH patients on anti-complement treatment; we first observed that this rare challenging condition may pertain to about 5% of PNH patients. Then we demonstrated that intensive IST, based on either polyclonal or monoclonal anti-lymphocyte antibodies can be safely delivered even in concomitance of eculizumab. Pharmacological lymphocyte depletion was achieved irrespective of terminal complement inhibition. Clinical efficacy was in the expected range as in broader AA populations, with an overall reponse rate of 50%. Based on these data, intensive IST delivered on top of eculizumab should be considered in PNH patients who develop severe AA during eculizumab treatment lacking a low-risk bone marrow transplant procedure. Disclosures Peffault de Latour: Amgen: Research Funding; Pfizer: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Alexion: Consultancy, Honoraria, Research Funding. Risitano:Alnylam: Research Funding; Novartis: Research Funding; Alexion Pharmaceuticals: Other: lecture fees, Research Funding; Rapharma: Research Funding.

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Complement- and inflammasome-mediated autoinflammation-paroxysmal nocturnal hemoglobinuria

10.1101/635573 ◽

2019 ◽

Cited By ~ 1

Author(s):

Britta Hoechsmann ◽

Yoshiko Murakami ◽

Makiko Osato ◽

Alexej Knaus ◽

Michi Kawamoto ◽

...

Keyword(s):

Bone Marrow ◽

Paroxysmal Nocturnal Hemoglobinuria ◽

Bone Marrow Failure ◽

Alternative Pathway ◽

Initial Step ◽

Clonal Expansion ◽

Cell Surface Expression ◽

Intravascular Hemolysis ◽

Complement Alternative Pathway ◽

Hematopoietic Stem

AbstractParoxysmal nocturnal hemoglobinuria (PNH) is an acquired hematopoietic stem cell disorder characterized by complement-mediated hemolysis and thrombosis, and bone marrow failure. Affected cells harbor somatic mutation in X-linkedPIGAgene, essential for the initial step in glycosylphosphatidylinositol (GPI) biosynthesis. Loss of GPI biosynthesis results in defective cell-surface expression of GPI-anchored complement regulators CD59 and DAF. The affected stem cells generate many abnormal blood cells after clonal expansion, which occurs under bone marrow failure. Here, we report the mechanistic basis of a disease entity, autoinflammation-paroxysmal nocturnal hemoglobinuria (AIF-PNH), caused by germline mutation plus somatic loss ofPIGTon chromosome 20q. A region containing maternally imprinted genes implicated in clonal expansion in 20q-myeloproliferative syndromes was lost together with normalPIGTfrom paternal chromosome 20. Taking these findings together with a lack of bone marrow failure, the mechanisms of clonal expansion in AIF-PNH appear to differ from those in PNH. AIF-PNH is characterized by intravascular hemolysis and recurrent autoinflammation, such as urticaria, arthralgia, fever and aseptic meningitis. Consistent with PIGT’s essential role in synthesized GPI’s attachment to precursor proteins, non-protein-linked free GPIs appeared on the surface of PIGT-defective cells. PIGT-defective THP-1 cells accumulated higher levels of C3 fragments and C5b-9 complexes, and secreted more IL-1β than PIGA-defective cells after activation of the complement alternative pathway. IL-1β secretion was dependent upon C5b-9 complexes, accounting for the effectiveness of the anti-C5 drug eculizumab for both intravascular hemolysis and autoinflammation. These results suggest that free GPIs enhance complement activation and inflammasome-mediated IL-1β secretion.

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How I Treat Paroxysmal nocturnal hemoglobinuria

Blood ◽

10.1182/blood.2019003812 ◽

2021 ◽

Author(s):

Robert A. Brodsky

Keyword(s):

Bone Marrow ◽

Hemolytic Anemia ◽

Paroxysmal Nocturnal Hemoglobinuria ◽

Bone Marrow Failure ◽

Clinical Development ◽

Clinical Heterogeneity ◽

Intravascular Hemolysis ◽

Complement Inhibitors ◽

Clinical Vignettes ◽

Terminal Complement

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, clonal, complement-mediated hemolytic anemia with protean manifestations. PNH can present as a hemolytic anemia, a form of bone marrow failure, a thrombophilia, or any combination of the above. Terminal complement inhibition is highly effective for treating intravascular hemolysis from PNH and virtually eliminates the risk of thrombosis, but is not effective for treating bone marrow failure. Here, we present a variety of clinical vignettes that highlight the clinical heterogeneity of PNH as well as the attributes and limitations of the two FDA-approved C5 inhibitors (eculizumab and ravulizumab) to treat PNH. We review the concept of pharmacokinetic and pharmacodynamic breakthrough hemolysis and briefly discuss new complement inhibitors upstream of C5 that are in clinical development. Lastly, we discuss the rare indications for bone marrow transplantation in PNH patients.

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