Comorbidities and complications in adult and paediatric patients with pyruvate kinase deficiency: Analysis from the Peak Registry.

Pyruvate kinase (PK) deficiency, a rare, congenital haemolytic anaemia caused by mutations in the PKLR gene, is associated with many clinical manifestations, but the full disease burden has yet to be characterised. The Peak Registry (NCT03481738) is an observational, longitudinal registry of adult and paediatric patients with PK deficiency. Here, we described comorbidities and complications in these patients by age at most recent visit and PKLR genotype. As of 13 May 2022, 241 patients were included in the analysis. In total, 48.3% had undergone splenectomy and 50.5% had received chelation therapy. History of iron overload (before enrolment/during follow-up) was common (52.5%), even in never-transfused patients (20.7%). Neonatal complications and symptoms included jaundice, splenomegaly and hepatomegaly, with treatment interventions required in 41.5%. Among adults, osteopenia/osteoporosis occurred in 19.0% and pulmonary hypertension in 6.7%, with median onset ages of 37, 33 and 22 years, respectively. Biliary events and bone health problems were common across PKLR genotypes. Among 11 patients who had thromboembolic events, eight had undergone prior splenectomy. Patients with PK deficiency may have many complications, which can occur early in and throughout life. Awareness of their high disease burden may help clinicians better provide appropriate monitoring and management of these patients.

A Rare Case of De Novo Beta-Thalassemia Diagnosed by Whole-Genome Sequencing in an Ethnically Danish Newborn.

In 2020, a 2-month-old ethnically Danish girl was diagnosed with ß-thalassemia after presenting with persistent jaundice. The peripheral blood smear showed significant aniso- and poikilocytosis, increased number of reticulocytes and erythroblastosis. Trio analysis of the index patient and both parents was performed by whole-genome sequencing. Here, both parents were found normal, however the analysis revealed an apparently de novo HBB:c.444A > C variant in the child. The child has recently been discharged three months after a successful bone marrow transplantation with a matched sibling-donor.

Designing a single-arm phase 2 clinical trial of mitapivat for adult patients with erythrocyte membranopathies (SATISFY): a framework for interventional trials in rare anaemias - pilot study protocol.

INTRODUCTION: Membranopathies encompass haemolytic disorders arising from genetic variants in erythrocyte membrane proteins, including hereditary spherocytosis and stomatocytosis. Congenital dyserythropoietic anaemia type II (CDA II) is associated with the SEC23B gene and can exhibit phenotypic similarities to membranopathies. Current treatment options for these conditions, apart from splenectomy, are primarily supportive. Mitapivat, a novel pyruvate kinase (PK) activator, has demonstrated efficacy in increasing haemoglobin levels and reducing haemolysis in patients with PK deficiency, thalassemia, sickle cell disease and a mouse model of hereditary spherocytosis. METHODS AND ANALYSES: Safety and efficacy of mitapivat sulfate in adult patients with erythrocyte membranopathies (SATISFY) is a prospective, multicentre, single-arm phase two trial involving approximately 25 adult patients (≥18 years) diagnosed with a membranopathy or CDA II. During the 8-week dose escalation period, subjects will receive an initial dose of 50 mg mitapivat two times per day and may increase to 100 mg two times per day at week 4 based on the safety and changes in haemoglobin levels. Patients tolerating mitapivat well may be eligible to continue in two consecutive 24-week fixed dose periods.The primary objective of this study is to evaluate the safety of mitapivat, assessed through the occurrence of treatment-emergent adverse events. Secondary objectives include assessing the effects of mitapivat on haemoglobin levels, haemolysis, erythropoiesis, patient-reported outcome measures and spleen size.SATISFY aims to assess the safety and efficacy of mitapivat in adult patients with red blood cell membranopathies and CDA II, with the aim of establishing proof-of-concept in patients living with these rare conditions. ETHICS AND DISSEMINATION: NCT05935202/CTIS:2023-503271-24-01. Findings will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov, NCT05935202. CTIS:2023-503271-24-01. Registered 07-July-2023. Protocol number: 2.1. https://clinicaltrials.gov/study/NCT05935202.

DAHEAN: A Danish nationwide study ensuring quality assurance through real-world data for suspected hereditary anemia patients.

BACKGROUND: Hereditary anemias are a group of genetic diseases prevalent worldwide and pose a significant health burden on patients and societies. The clinical phenotype of hereditary anemias varies from compensated hemolysis to life-threatening anemia. They can be roughly categorized into three broad categories: hemoglobinopathies, membranopathies, and enzymopathies. Traditional therapeutic approaches like blood transfusions, iron chelation, and splenectomy are witnessing a paradigm shift with the advent of targeted treatments. However, access to these treatments remains limited due to lacking or imprecise diagnoses. The primary objective of the study is to establish accurate diagnoses for patients with hereditary anemias, enabling optimal management. As a secondary objective, the study aims to enhance our diagnostic capabilities. RESULTS: The DAHEAN study is a nationwide cohort study that collects advanced phenotypic and genotypic data from patients suspected of having hereditary anemias from all pediatric and hematological departments in Denmark. The study deliberates monthly by a multidisciplinary anemia board involving experts from across Denmark. So far, fifty-seven patients have been thoroughly evaluated, and several have been given diagnoses not before seen in Denmark. CONCLUSIONS: The DAHEAN study and infrastructure harness recent advancements in diagnostic tools to offer precise diagnoses and improved management strategies for patients with hereditary anemias.

Diagnosis and management of Evans syndrome in adults: first consensus recommendations.

Evans syndrome is a rare disease marked by a severe clinical course, high relapse rate, infectious and thrombotic complications, and sometimes fatal outcome. Management is highly heterogeneous. There are several case reports but few large retrospective studies and no prospective or randomised trials. Here, we report the results of the first consensus-based expert recommendations aimed at harmonising the diagnosis and management of Evans syndrome in adults. After reviewing the literature, we used a fuzzy Delphi consensus method, with two rounds of a 42-item questionnaire that were scored by a panel of 13 international experts from five countries using a 7-point Likert scale. Panellists were selected by the core panel on the basis of their personal experience and previous publications on Evans syndrome and immune cytopenias; they met virtually throughout 2023. The panellists recommended extensive clinical and laboratory diagnostic tests, including bone marrow evaluation and CT scan, and an aggressive front-line therapy with prednisone (with or without intravenous immunoglobulins), with different treatment durations and tapering for immune thrombocytopenia and autoimmune haemolytic anaemias (AIHAs). Rituximab was strongly recommended as first-line treatment in cold-type AIHA and as second-line treatment in warm-type AIHA and patients with immune thrombocytopenia and antiphospholipid antibodies, previous thrombotic events, or associated lymphoproliferative diseases. However, rituximab was discouraged for patients with immunodeficiency or severe infections, with the same applying to splenectomy. Thrombopoietin receptor agonists were recommended for chronic immune thrombocytopenia and in the case of previous grade 4 infection. Fostamatinib was recommended as third-line or further-line treatment and suggested as second-line therapy for patients with previous thrombotic events. Immunosuppressive agents have been moved to third-line or further-line treatment. The panellists recommended the use of recombinant erythropoietin in AIHA in the case of inadequate reticulocyte counts, use of the complement inhibitor sutimlimab for relapsed cold AIHA, and the combination of rituximab plus bendamustine in Evans syndrome secondary to lymphoproliferative disorders. Finally, recommendations were given for supportive therapy, platelet or red blood cell transfusions, and thrombotic and antibiotic prophylaxis. These consensus-based recommendations should facilitate best practice for diagnosis and management of Evans syndrome in clinical practice.

A Novel ß-Globin Variant, Hb Odder [HBB: C.316C > G; CD105 (Leu > Val)].

We report the discovery of a novel ß-globin gene variant, Hb Odder, characterized by a single nucleotide substitution; HBB:c.316C > G; CD105 (Leu > Val). This variant emerged incidentally during routine HbA1c measurements for diabetes monitoring. The patient exhibited no clinical or biochemical evidence of anemia or hemolysis. Our data on this variant suggest that Hb Odder is benign, regrettably limitations in our data make formal evaluations of stability and oxygen affinity impossible; additionally this emphasizes the importance of considering hemoglobin variants in the differential diagnosis of abnormal Hb A1c levels and suggest that laboratories should use alternative methods for the correct measurement of Hb A1c when hemoglobin variants interfere with diabetes monitoring. Notably, three other mutations have been described at codon 105 of the ß globin chains and correspond to three Hb variants with different characteristics: Hb South Milwaukee, Hb Bellevue IV and Hb St. George.

Clinically meaningful improvements in patient-reported outcomes in mitapivat-treated patients with pyruvate kinase deficiency.

Clinically meaningful benefits in the signs, symptoms, and impacts of #PKDeficiency as assessed by disease-specific patient-reported outcome measures were observed in mitapivat-treated adult patients in two phase 3 clinical trials.

Genetic polymorphisms in IL-2, IL-10 and FOXP3 are associated with autoimmune neutropenia in early childhood and autoantibody specificity in a Danish cohort.

Autoimmune neutropenia (AIN) in early childhood is characterized by chronic neutropenia and positivity for human neutrophil antibodies (HNA), resulting in the excessive destruction of neutrophils. The association between regulatory T cells (Tregs) and AIN has been described, and in this study, we investigated three Treg-associated genes, IL-2, IL-10 and FOXP3. The frequencies of three single nucleotide polymorphisms (SNPs) in IL-2 -330T>G (rs2069762), +114G>T (rs2069763) and IVS3-116 A>G (rs2069772), four SNPs in IL-10 -3575T>A (rs1800890), -1082G>A (rs1800896), -819 C>T (rs1800871) and -592 C>A (rs1800872) and three SNPs in FOXP3 -3499 A>G (rs3761547), -3279 C>A (rs3761548) and -924 A>G (rs2232365) were compared between 166 Danish AIN patients and 358 healthy controls. Disease association was observed for IL-2 IVS3-116 GG (p = 0.0081, OR = 0.35 [0.15-0.80]), IL-10 -3575 TT (p = 0.0078, OR = 1.71 [1.16-2.54]) and IL-10 -1082 AA (p = 0.014, OR = 1.76 [1.14-2.72]) in all patients and FOXP3 -924 (p = 0.0005, A OR = 0.41 [0.25-0.68] and G OR = 2.42 [1.46-4.01]) in male patients. None of the associations were linked to antibody specificity. Disease-associated haplotypes were observed in IL-2 and FOXP3. IL-2 -330T/+114 T/IVS3-116A was associated with anti-FcγRIIIb-positive patients (p = 0.012, OR = 2.07 [1.18-3.62]). FOXP3 -3499A/-3279C/-924A was associated with anti-HNA-1a-positive male patients (p = 0.016, OR = 0.41 [0.20-0.83]), and ACG was associated with female patients, both in the combined group (p = 0.006, OR = NA) and the anti-FcγRIIIb-positive group (p = 0.002, OR = NA). We conclude that our findings reveal a correlation between SNP in Treg-associated genes and AIN, indicating that AIN could be driven by dysfunction of immune homeostatic-evolving Tregs.

Iron, hemochromatosis genotypes, and risk of infections: a cohort study of 142 188 general population individuals.

ABSTRACT: It is unclear whether risk of infection is increased in individuals with hereditary hemochromatosis and in individuals with low or high plasma iron, transferrin saturation, or ferritin. Therefore, we tested whether high and low iron, transferrin saturation, and ferritin are associated with risk of infections observationally and genetically through HFE genotypes. We studied 142 188 Danish general population individuals. Iron, transferrin saturation, and ferritin were measured in 136 656, 136 599, and 38 020 individuals, respectively. HFE was genotyped for C282Y and H63D in 132 542 individuals. Median follow-up after study enrollment was 8 years (range, 0-38) for hospital and emergency room admissions with infections (n = 20 394) using the National Patient Register, covering all Danish hospitals. Hazard ratios for any infection were 1.20 (95% confidence interval [CI], 1.12-1.28) and 1.14 (95% CI, 1.07-1.22) in individuals with plasma iron ≤5th or ≥95th percentile compared with individuals with iron from 26th to 74th percentiles. Findings for transferrin saturation were similar, whereas infection risk was not increased in individuals with ferritin ≤5th or ≥95th percentile. Hazard ratios in C282Y homozygotes vs noncarriers were 1.40 (95% CI, 1.16-1.68) for any infection, 1.69 (95% CI, 1.05-2.73) for sepsis, and 2.34 (95% CI, 1.41-3.90) for death from infectious disease. Risk of infection was increased in C282Y homozygotes with normal plasma iron, transferrin saturation, or ferritin, and in C282Y homozygotes without liver disease, diabetes, and/or heart failure. In summary, low and high plasma iron and transferrin saturation were independently associated with increased infection risk. C282Y homozygotes had increased risk of any infection, sepsis, and death from infections. Even C282Y homozygotes with normal iron, transferrin saturation, or ferritin, not currently recommended for genotyping, had increased infection risk.

Thrombosis Tendency After Splenectomy in a Danish Family With Hemoglobin Volga, and a Literature Review.

Hemoglobin (Hb) Volga is a rare, unstable ß-chain hemoglobin variant (ß27 Ala→Asp), causing chronic hemolytic anemia. This study presents two members of a Danish family, splenectomized due to Hb Volga at and with multiple thrombotic events. The proband was diagnosed with Hb Volga 9 years old and splenectomy was performed as a part of treatment. Throughout his life, he experienced multiple superficial thrombophlebitis, two episodes of distal deep venous thrombosis (DVT) on lower extremities (age 32 and 33) and a transient ischemic attack (TIA) presented as amaurosis fugax (age 51). Thrombophilia investigation was normal. The proband's son was diagnosed with Hb Volga and underwent splenectomy at the age of 6. Despite anticoagulation therapy, he suffered from multiple venous thromboembolic events in his youth and died of chronic pulmonary embolism (PE)/pulmonary hypertension combined with infection. Given the observed propensity for multiple thromboses in these two patients, a literature review was conducted investigating reported occurrence of thrombotic events in individuals with Hb Volga.Currently 25 cases of Hb Volga are reported worldwide. The clinical symptoms primarily described are related to hemolytic anemia. Splenectomy is reported in 15 patients. Thromboses have previously been reported in only three patients who were also splenectomized. These cases involved DVT and PE, myocardial infarction, and an unspecified thrombotic event. The proband represents the first reported Hb Volga case with both venous and arterial thrombotic disorders. The exact mechanism underlying thrombotic tendency in patients with Hb Volga remains unknown, but it is probably associated with splenectomy.

High-resolution HLA genotyping identifies risk alleles in both class I and II for primary autoimmune neutropenia in early childhood in a Danish cohort.

HLA studies in patients with autoimmune neutropenia (AIN) have shown very consistent results for the association with HLA class II alleles at low resolution. This study aimed to examine the association of both HLA class I and class II at high resolution to clarify the contribution of risk alleles to the disease. A total of 107 AIN patients were genotyped for six loci of HLA class I (HLA-A, -B and -C) and class II (HLA-DRB1, -DQB1, and -DPB1) genes by a high-resolution (3-field, 6-digit) analysis and compared with HLA typing of 1000 healthy controls. Compared with the controls, the allele frequencies were significantly higher in AIN patients for A*02:17:01G, C*01:02:01G, DRB1*10:01:01G, DRB1*14:01:01G, DRB1*16:01:01G, DQB1*05:02:01G, and DQB1*05:03:01G but lower significant for C*03:04:01G, DRB1*04:01:01G, DRB1*13:02:01G, DQB1*03:02:01G, and DQB1*06:04:01G. Frequently associated two-locus haplotypes were found to be DRB1*10:01:01G-DQB1*05:01:01G and DRB1*16:01:01G-DQB1*05:02:01G, while the S2 (Q- or D-KRAA) shared epitope (SE) was associated with lower risk. A unique association with HLA alleles was observed between patients with specific anti-HNA-1a antibodies and broad-reacting anti-FcγRIIIb. Anti-HNA-1a antibody-positive patients were associated with C*01:02:01G, DRB1*01:01:01G, DRB1*16:01:01G, DQB1*05:01:01G, DQB1*05:02:01G, DQB1*06:04:01G, and DPB1*10:01:01G; the two-locus haplotypes DRB1*01:01:01G-DQB1*05:01:01G and DRB1*16:01:01G-DQB1*05:02:01G; and the S3P (Q- or R-RRAA) SE. Anti-FcγRIIIb antibody-positive patients were associated with the alleles A*02:17:01G, DRB1*10:01:01G, and DQB1*05:02:01G; the haplotypes DRB1*10:01:01G-DQB1*05:01:01G and DRB1*11:01:02G-DQB1*05:02:01G; and the S3D (DRRAA) SE. The different associations regarding FcγRIIIb antibody specificities could indicate disease heterogeneity.

Glucose phosphate isomerase deficiency demasked by whole-genome sequencing: a case report.

BACKGROUND: Glucose-6-phosphate isomerase deficiency is a rare genetic disorder causing hereditary nonspherocytic hemolytic anemia. It is the second most common glycolytic enzymopathy in red blood cells. About 90 cases are reported worldwide, with symptoms including chronic hemolytic anemia, jaundice, splenomegaly, gallstones, cholecystitis, and in severe cases, neurological impairments, hydrops fetalis, and neonatal death. CASE PRESENTATION: This paper details the case of the first Danish patient diagnosed with glucose-6-phosphate isomerase deficiency. The patient, a 27-year-old white female, suffered from lifelong anemia of unknown origin for decades. Diagnosis was established through whole-genome sequencing, which identified two GPI missense variants: the previously documented variant p.(Thr224Met) and a newly discovered variant p.(Tyr341Cys). The pathogenicity of these variants was verified enzymatically. CONCLUSIONS: Whole-genome sequencing stands as a potent tool for identifying hereditary anemias, ensuring optimal management strategies.

Decoding the historical tale: COVID-19 impact on haematological malignancy patients-EPICOVIDEHA insights from 2020 to 2022.

Background: The COVID-19 pandemic heightened risks for individuals with hematological malignancies due to compromised immune systems, leading to more severe outcomes and increased mortality. While interventions like vaccines, targeted antivirals, and monoclonal antibodies have been effective for the general population, their benefits for these patients may not be as pronounced. Methods: The EPICOVIDEHA registry (National Clinical Trials Identifier, NCT04733729) gathers COVID-19 data from hematological malignancy patients since the pandemic's start worldwide. It spans various global locations, allowing comprehensive analysis over the first three years (2020-2022). Findings: The EPICOVIDEHA registry collected data from January 2020 to December 2022, involving 8767 COVID-19 cases in hematological malignancy patients from 152 centers across 41 countries, with 42% being female. Over this period, there was a significant reduction in critical infections and an overall decrease in mortality from 29% to 4%. However, hospitalization, particularly in the ICU, remained associated with higher mortality rates. Factors contributing to increased mortality included age, multiple comorbidities, active malignancy at COVID-19 onset, pulmonary symptoms, and hospitalization. On the positive side, vaccination with one to two doses or three or more doses, as well as encountering COVID-19 in 2022, were associated with improved survival. Interpretation: Patients with hematological malignancies still face elevated risks, despite reductions in critical infections and overall mortality rates over time. Hospitalization, especially in ICUs, remains a significant concern. The study underscores the importance of vaccination and the timing of COVID-19 exposure in 2022 for enhanced survival in this patient group. Ongoing monitoring and targeted interventions are essential to support this vulnerable population, emphasizing the critical role of timely diagnosis and prompt treatment in preventing severe COVID-19 cases. Funding: Not applicable.

Mitapivat improves ineffective erythropoiesis and iron overload in adult patients with pyruvate kinase deficiency.

ABSTRACT: Pyruvate kinase (PK) deficiency is a rare, hereditary disease characterized by chronic hemolytic anemia. Iron overload is a common complication regardless of age, genotype, or transfusion history. Mitapivat, an oral, allosteric PK activator, improves anemia and hemolysis in adult patients with PK deficiency. Mitapivat's impact on iron overload and ineffective erythropoiesis was evaluated in adults with PK deficiency who were not regularly transfused in the phase 3 ACTIVATE trial and long-term extension (LTE) (#NCT03548220/#NCT03853798). Patients in the LTE received mitapivat throughout ACTIVATE/LTE (baseline to week 96; mitapivat-to-mitapivat [M/M] arm) or switched from placebo (baseline to week 24) to mitapivat (week 24 to week 96; placebo-to-mitapivat [P/M] arm). Changes from baseline in markers of iron overload and erythropoiesis were assessed to week 96. Improvements in hepcidin (mean, 4770.0 ng/L; 95% confidence interval [CI], -1532.3 to 11 072.3), erythroferrone (mean, -9834.9 ng/L; 95% CI, -14 328.4 to -5341.3), soluble transferrin receptor (mean, -56.0 nmol/L; 95% CI, -84.8 to -27.2), and erythropoietin (mean, -32.85 IU/L; 95% CI, -54.65 to -11.06) were observed in the M/M arm (n = 40) from baseline to week 24, sustained to week 96. No improvements were observed in the P/M arm (n = 40) to week 24; however, upon transitioning to mitapivat, improvements similar to those observed in the M/M arm were seen. Mean changes from baseline in liver iron concentration by magnetic resonance imaging at week 96 in the M/M arm and the P/M arm were -2.0 mg Fe/g dry weight (dw; 95% CI, -4.8 to -0.8) and -1.8 mg Fe/g dw (95% CI, -4.4 to 0.80), respectively. Mitapivat is the first disease-modifying pharmacotherapy shown to have beneficial effects on iron overload and ineffective erythropoiesis in patients with PK deficiency. This trial was registered at www.ClinicalTrials.gov as #NCT03548220 (ACTIVATE) and #NCT03853798 (LTE).

Diagnosis and management of pyruvate kinase deficiency: international expert guidelines.

Pyruvate kinase (PK) deficiency is the most common cause of chronic congenital non-spherocytic haemolytic anaemia worldwide, with an estimated prevalence of one in 100 000 to one in 300 000 people. PK deficiency results in chronic haemolytic anaemia, with wide ranging and serious consequences affecting health, quality of life, and mortality. The goal of the International Guidelines for the Diagnosis and Management of Pyruvate Kinase Deficiency was to develop evidence-based guidelines for the clinical care of patients with PK deficiency. These clinical guidelines were developed by use of GRADE methodology and the AGREE II framework. Experts were invited after consideration of area of expertise, scholarly contributions in PK deficiency, and country of practice for global representation. The expert panel included 29 expert physicians (including adult and paediatric haematologists and other subspecialists), geneticists, laboratory specialists, nurses, a guidelines methodologist, patients with PK deficiency, and caregivers from ten countries. Five key topic areas were identified, the panel prioritised key questions, and a systematic literature search was done to generate evidence summaries that were used in the development of draft recommendations. The expert panel then met in person to finalise and vote on recommendations according to a structured consensus procedure. Agreement of greater than or equal to 67% among the expert panel was required for inclusion of a recommendation in the final guideline. The expert panel agreed on 31 total recommendations across five key topics: diagnosis and genetics, monitoring and management of chronic complications, standard management of anaemia, targeted and advanced therapies, and special populations. These new guidelines should facilitate best practices and evidence-based PK deficiency care into clinical practice.