ABSTRACT
Background The efficacy and safety of wilate (human von Willebrand factor/coagulation factor VIII) in patients with von Willebrand disease (VWD) has been demonstrated in clinical trials. Here, we present real-world data on the use of wilate for the routine care of patients with VWD. Objectives The objectives of this observational, prospective, phase 4 study were to evaluate the safety, tolerability, and effectiveness of wilate in on-demand treatment of bleeding episodes (BEs), long-term prophylaxis, and surgical prophylaxis among patients with any type of VWD. Methods Patients were enrolled at 31 study centers in 11 countries and followed for up to 2 years. Safety endpoints included adverse drug reactions (ADRs) and drug tolerability. Effectiveness was assessed using annualized bleeding rates (ABRs) during prophylaxis and predefined criteria for the treatment of BEs and surgical prophylaxis. Results A total of 111 patients (76 [68%] female) including 41 (37%) children were treated with wilate. Twenty-five patients received prophylaxis, 29 on-demand treatment, and 62 surgical prophylaxis. Tolerability was rated by patients as "excellent" for 96.2% of 6,497 infusions. No unexpected ADRs or thrombotic events were reported. Median ABR during prophylaxis was 1.9. Effectiveness was assessed as "excellent" or "good" by patients and investigators for 100% of BEs treated on-demand, 98% (patient rating) and 99% (investigator rating) of breakthrough BEs, and 99% of surgical procedures (investigator rating). Conclusion wilate was safe, well tolerated, and effective for the prevention and treatment of bleeding in pediatric and adult VWD patients in a real-world setting.
ABSTRACT
BACKGROUND: Pyruvate kinase deficiency (PKD) is a rare, autosomal recessive red blood cell enzyme disorder, which leads to lifelong hemolytic anemia and associated complications from the disease and its management. METHODS: An international, multicenter registry enrolled 124 individuals younger than 18 years old with molecularly confirmed PKD from 29 centers. Retrospective and prospective clinical data were collected. RESULTS: There was a wide range in the age at diagnosis from 0 to 16 years. Presentation in the newborn period ranged from asymptomatic to neonatal jaundice to fulminant presentations of fetal distress, myocardial depression, and/or liver failure. Children <5 years old were significantly more likely to be transfused than children >12 to <18 years (53% vs. 14%, p = .0006), which correlated with the timing of splenectomy. Regular transfusions were most common in children with two severe PKLR variants. In regularly transfused children, the nadir hemoglobin goal varied considerably. Impact on quality of life was a common reason for treatment with regular blood transfusions and splenectomy. Splenectomy increased the hemoglobin and decreased transfusion burden in most children but was associated with infection or sepsis (12%) and thrombosis (1.3%) even during childhood. Complication rates were high, including iron overload (48%), perinatal complications (31%), and gallstones (20%). CONCLUSIONS: There is a high burden of disease in children with PKD, with wide practice variation in monitoring and treatment. Clinicians must recognize the spectrum of the manifestations of PKD for early diagnostic testing, close monitoring, and management to avoid serious complications in childhood.
Subject(s)
Anemia, Hemolytic, Congenital Nonspherocytic , Pyruvate Kinase/deficiency , Pyruvate Metabolism, Inborn Errors , Adolescent , Anemia, Hemolytic, Congenital Nonspherocytic/diagnosis , Anemia, Hemolytic, Congenital Nonspherocytic/genetics , Anemia, Hemolytic, Congenital Nonspherocytic/therapy , Child , Child, Preschool , Humans , Prospective Studies , Pyruvate Metabolism, Inborn Errors/diagnosis , Pyruvate Metabolism, Inborn Errors/genetics , Pyruvate Metabolism, Inborn Errors/therapy , Quality of Life , Retrospective StudiesABSTRACT
OBJECTIVES: Pyruvate kinase (PK) deficiency is caused by PKLR gene mutations, leading to defective red blood cell glycolysis and hemolytic anemia. Rates of comorbidities and complications by transfusion history and relative to the general population remain poorly quantified. METHODS: Data for patients aged ≥ 18 years with two confirmed PKLR mutations were obtained from the PK deficiency Natural History Study (NCT02053480). Frequencies of select conditions were compared with an age- and sex-matched cohort from a general insured US population without PK deficiency. RESULTS: Compared with the matched population (n = 1220), patients with PK deficiency (n = 122) had significantly higher lifetime rates of osteoporosis, liver cirrhosis, and pulmonary hypertension; splenectomy and cholecystectomy rates were also significantly higher in the 8 years before the index date. Sixty-five (53.3%) patients with PK deficiency were classified as regularly transfused, 30 (24.6%) as occasionally transfused, and 27 (22.1%) as never transfused. Regularly transfused patients were significantly more likely than never transfused patients to have had splenectomy, cholecystectomy, and/or thrombosis. Liver iron overload was reported in 62% of patients and occurred regardless of transfusion cohort. CONCLUSIONS: Even never transfused patients with PK deficiency had higher rates of select comorbidities and complications than individuals without PK deficiency.
Subject(s)
Anemia, Hemolytic, Congenital Nonspherocytic/epidemiology , Pyruvate Kinase/deficiency , Pyruvate Metabolism, Inborn Errors/epidemiology , Adult , Alleles , Anemia, Hemolytic, Congenital Nonspherocytic/etiology , Comorbidity , Female , Genotype , Humans , Male , Middle Aged , Mutation , Prevalence , Pyruvate Kinase/genetics , Pyruvate Metabolism, Inborn Errors/etiology , Young AdultABSTRACT
Pyruvate kinase (PK) deficiency is a rare recessive congenital hemolytic anemia caused by mutations in the PKLR gene. This study reports the molecular features of 257 patients enrolled in the PKD Natural History Study. Of the 127 different pathogenic variants detected, 84 were missense and 43 non-missense, including 20 stop-gain, 11 affecting splicing, five large deletions, four in-frame indels, and three promoter variants. Within the 177 unrelated patients, 35 were homozygous and 142 compound heterozygous (77 for two missense, 48 for one missense and one non-missense, and 17 for two non-missense variants); the two most frequent mutations were p.R510Q in 23% and p.R486W in 9% of mutated alleles. Fifty-five (21%) patients were found to have at least one previously unreported variant with 45 newly described mutations. Patients with two non-missense mutations had lower hemoglobin levels, higher numbers of lifetime transfusions, and higher rates of complications including iron overload, extramedullary hematopoiesis, and pulmonary hypertension. Rare severe complications, including lower extremity ulcerations and hepatic failure, were seen more frequently in patients with non-missense mutations or with missense mutations characterized by severe protein instability. The PKLR genotype did not correlate with the frequency of complications in utero or in the newborn period. With ICCs ranging from 0.4 to 0.61, about the same degree of clinical similarity exists within siblings as it does between siblings, in terms of hemoglobin, total bilirubin, splenectomy status, and cholecystectomy status. Pregnancy outcomes were similar across genotypes in PK deficient women. This report confirms the wide genetic heterogeneity of PK deficiency.
Subject(s)
Anemia, Hemolytic, Congenital Nonspherocytic/genetics , Genetic Association Studies/methods , Pyruvate Kinase/deficiency , Pyruvate Metabolism, Inborn Errors/genetics , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Pyruvate Kinase/genetics , Young AdultABSTRACT
INTRODUCTION: Turoctocog alfa is a recombinant, B domain-truncated factor VIII (FVIII) approved for patients with haemophilia A. AIM: To evaluate the safety and efficacy of turoctocog alfa in previously untreated patients (PUPs) with severe haemophilia A. METHODS: Guardian 4 was a multicentre, multinational, non-randomized, open-label phase 3 trial comprising a main and extension phase. The former concluded once ≥ 50 patients had received treatment for ≥ 50 exposure days (EDs) or developed inhibitors. Patients received turoctocog alfa intravenously for prevention and treatment of bleeds. The primary endpoint was the incidence rate of FVIII inhibitors (≥0.6 Bethesda Units) reported during the first 50 EDs. RESULTS: Of the 58 patients who completed the main phase, 25 (43.1%) patients developed inhibitors (detected within 6-24 [mean: 14.2] EDs from treatment start). High-risk mutations were identified in 60% of patients who developed inhibitors in the main phase and were a significant predictor of inhibitor development (P = .003). Of the 21 patients who started immune tolerance induction therapy, 85.7% completed treatment with a negative inhibitor test (note that data on the last 3 patients completing ITI are based on information collated from sites prior to the final database lock). Haemostatic response (including missing values as failure) was rated as 'excellent' or 'good' for 86.1% of bleeds occurring during prophylaxis. The estimated mean annualized bleeding rate for patients on prophylaxis was 4.26 bleeds/patient/year (95% CI: 3.34 - 5.44). CONCLUSIONS: Turoctocog alfa was effective at preventing and stopping bleeds and was well tolerated. Inhibitor development was within the expected range for this PUP population.
Subject(s)
Factor VIII/adverse effects , Factor VIII/therapeutic use , Hemophilia A/drug therapy , Hemophilia A/prevention & control , Child , Humans , Infant , Infant, Newborn , Male , Mutation/genetics , Treatment OutcomeABSTRACT
BACKGROUND: Pyruvate kinase deficiency is caused by mutations in PKLR and leads to congenital hemolytic anemia. Mitapivat is an oral, small-molecule allosteric activator of pyruvate kinase in red cells. METHODS: In this uncontrolled, phase 2 study, we evaluated the safety and efficacy of mitapivat in 52 adults with pyruvate kinase deficiency who were not receiving red-cell transfusions. The patients were randomly assigned to receive either 50 mg or 300 mg of mitapivat twice daily for a 24-week core period; eligible patients could continue treatment in an ongoing extension phase. RESULTS: Common adverse events, including headache and insomnia, occurred at the time of drug initiation and were transient; 92% of the episodes of headache and 47% of the episodes of insomnia resolved within 7 days. The most common serious adverse events, hemolytic anemia and pharyngitis, each occurred in 2 patients (4%). A total of 26 patients (50%) had an increase of more than 1.0 g per deciliter in the hemoglobin level. Among these patients, the mean maximum increase was 3.4 g per deciliter (range, 1.1 to 5.8), and the median time until the first increase of more than 1.0 g per deciliter was 10 days (range, 7 to 187); 20 patients (77%) had an increase of more than 1.0 g per deciliter in the hemoglobin level at more than 50% of visits during the core study period, with improvement in markers of hemolysis. The response was sustained in all 19 patients remaining in the extension phase, with a median follow-up of 29 months (range, 22 to 35). Hemoglobin responses were observed only in patients who had at least one missense PKLR mutation and were associated with the red-cell pyruvate kinase protein level at baseline. CONCLUSIONS: The administration of mitapivat was associated with a rapid increase in the hemoglobin level in 50% of adults with pyruvate kinase deficiency, with a sustained response during a median follow-up of 29 months during the extension phase. Adverse effects were mainly low-grade and transient. (Funded by Agios Pharmaceuticals; ClinicalTrials.gov number, NCT02476916.).
Subject(s)
Anemia, Hemolytic, Congenital Nonspherocytic/drug therapy , Hemoglobins/metabolism , Piperazines/administration & dosage , Pyruvate Kinase/deficiency , Pyruvate Metabolism, Inborn Errors/drug therapy , Quinolines/administration & dosage , Administration, Oral , Adolescent , Adult , Anemia, Hemolytic, Congenital Nonspherocytic/blood , Anemia, Hemolytic, Congenital Nonspherocytic/genetics , Catechols , Drug Administration Schedule , Female , Follow-Up Studies , Headache/chemically induced , Humans , Male , Mutation , Piperazines/adverse effects , Pyruvate Kinase/blood , Pyruvate Kinase/genetics , Pyruvate Metabolism, Inborn Errors/blood , Pyruvate Metabolism, Inborn Errors/genetics , Quinolines/adverse effects , Sleep Initiation and Maintenance Disorders/chemically induced , Tyrphostins , Young AdultABSTRACT
Serum ferritin reflects total body iron stores, thus a low serum ferritin is used as a parameter of iron deficiency. In healthy adults in Japan, urine ferritin levels were about 5% of serum ferritin levels, with a correlation coefficient of 0.79. It is not known whether a low urine ferritin could serve as a non-invasive screen for iron deficiency. If so, this might be useful for neonates and young children, avoiding phlebotomy to screen for iron deficiency. However, for urinary ferritin screening to be feasible, ferritin must be measurable in the urine and correlate with serum ferritin. Testing should also clarify whether the iron content of ferritin in serum and urine are similar. In this pilot feasibility study we measured ferritin in paired serum and urine samples of healthy adult males, healthy term neonates, growing preterm neonates, and children who had very high serum ferritin levels from liver disorders or iron overload. We detected ferritin in every urine sample, and found a correlation with paired serum ferritin (Spearman correlation coefficient 0.78 of log10-transformed values). These findings suggest merit in further studying urinary ferritin in select populations, as a potential non-invasive screen to assess iron stores.
Subject(s)
Ferritins/blood , Ferritins/urine , Mass Screening/methods , Adult , Anemia, Iron-Deficiency , Child , Humans , Infant, Newborn , Japan , Liver Diseases , Male , Pilot ProjectsSubject(s)
Iron Overload/etiology , Iron Overload/metabolism , Pyruvate Kinase/deficiency , Biomarkers , Blood Transfusion , DNA Mutational Analysis , Disease Management , Humans , Iron/metabolism , Iron Overload/diagnosis , Iron Overload/epidemiology , Magnetic Resonance Imaging , Mutation , PrevalenceABSTRACT
Herein we report a case series of seven newborn infants, all apparently well at birth, who in the period since 2009 were cared for in the State of Utah with acute bilirubin encephalopathy (ABE). This report summarizes our attempts to define common features of these seven through a state-wide voluntary registry, as a step toward devising new means of preventing such cases in the future. In previous reports of ABE, many of the affected neonates had no clearly defined explanation for their progressive hyperbilirubinemia. Our efforts to identify clear explanations in all seven cases included next generation DNA sequencing, testing a panel of 28 genes involved in bilirubin production and metabolism. We found that hemolytic disease was a unifying feature of these seven; two had DAT (+) Anti-D or anti-c hemolysis, while five had confirmed mutations in genes involved in bilirubin production and or metabolism that were previously unrecognized in these families.
Subject(s)
Bilirubin/genetics , Kernicterus/genetics , Bilirubin/analysis , Hemolysis , High-Throughput Nucleotide Sequencing , Humans , Infant, Newborn , Kernicterus/etiology , Mutation , Registries , UtahABSTRACT
An international, multicenter registry was established to collect retrospective and prospective clinical data on patients with pyruvate kinase (PK) deficiency, the most common glycolytic defect causing congenital nonspherocytic hemolytic anemia. Medical history and laboratory and radiologic data were retrospectively collected at enrollment for 254 patients with molecularly confirmed PK deficiency. Perinatal complications were common, including anemia that required transfusions, hyperbilirubinemia, hydrops, and prematurity. Nearly all newborns were treated with phototherapy (93%), and many were treated with exchange transfusions (46%). Children age 5 years and younger were often transfused until splenectomy. Splenectomy (150 [59%] of 254 patients) was associated with a median increase in hemoglobin of 1.6 g/dL and a decreased transfusion burden in 90% of patients. Predictors of a response to splenectomy included higher presplenectomy hemoglobin (P = .007), lower indirect bilirubin (P = .005), and missense PKLR mutations (P = .0017). Postsplenectomy thrombosis was reported in 11% of patients. The most frequent complications included iron overload (48%) and gallstones (45%), but other complications such as aplastic crises, osteopenia/bone fragility, extramedullary hematopoiesis, postsplenectomy sepsis, pulmonary hypertension, and leg ulcers were not uncommon. Overall, 87 (34%) of 254 patients had both a splenectomy and cholecystectomy. In those who had a splenectomy without simultaneous cholecystectomy, 48% later required a cholecystectomy. Although the risk of complications increases with severity of anemia and a genotype-phenotype relationship was observed, complications were common in all patients with PK deficiency. Diagnostic testing for PK deficiency should be considered in patients with apparent congenital hemolytic anemia and close monitoring for iron overload, gallstones, and other complications is needed regardless of baseline hemoglobin. This trial was registered at www.clinicaltrials.gov as #NCT02053480.
Subject(s)
Anemia, Hemolytic, Congenital Nonspherocytic/diagnosis , Genetic Association Studies , Pyruvate Kinase/deficiency , Pyruvate Metabolism, Inborn Errors/diagnosis , Adolescent , Adult , Anemia, Hemolytic, Congenital Nonspherocytic/etiology , Anemia, Hemolytic, Congenital Nonspherocytic/metabolism , Anemia, Hemolytic, Congenital Nonspherocytic/therapy , Blood Transfusion , Child , Child, Preschool , Cholecystectomy/adverse effects , Cholecystectomy/methods , Combined Modality Therapy , Enzyme Activation , Female , Genotype , Humans , Infant , Infant, Newborn , Male , Middle Aged , Mutation , Phenotype , Pyruvate Kinase/metabolism , Pyruvate Metabolism, Inborn Errors/etiology , Pyruvate Metabolism, Inborn Errors/metabolism , Pyruvate Metabolism, Inborn Errors/therapy , Splenectomy/adverse effects , Splenectomy/methods , Symptom Assessment , Treatment Outcome , Young AdultABSTRACT
The congenital dyserythropoietic anemias are a heterogeneous group of disorders characterized by anemia and ineffective erythropoiesis. Congenital dyserythropoietic anemia type I (CDA1) can present in utero with hydrops fetalis, but more often it presents in childhood or adulthood with moderate macrocytic anemia, jaundice, and progressive iron-overload. CDA1 is inherited in an autosomal recessive manner, with biallelic pathogenic variants in CDAN1 or C15orf41. This case report documents a severe fetal presentation of CDA1 where we identified two novel compound heterozygous mutations in CDAN1 and describes the associated pathologic findings and levels of iron-regulatory proteins hepcidin, erythroferrone, and GDF15.
Subject(s)
Anemia, Dyserythropoietic, Congenital/diagnosis , Anemia, Dyserythropoietic, Congenital/genetics , Genetic Association Studies , Genetic Predisposition to Disease , Glycoproteins/genetics , Heterozygote , Mutation , Adult , Anemia, Dyserythropoietic, Congenital/blood , Biomarkers , Biopsy , Bone Marrow , Female , Humans , Infant, Newborn , Male , Nuclear ProteinsABSTRACT
Various mutations in the genes encoding alpha spectrin (SPTA1) or beta spectrin (SPTB) are known to cause erythrocyte membrane disorders, sometimes associated with severe neonatal jaundice and anemia. We used a next-generation sequencing panel to evaluate 3 unrelated neonates who had puzzling cases of nonimmune hemolytic jaundice. In each case, we identified novel mutations in either SPTA1 or SPTB. Correlating erythrocyte morphology, clinical course, and computational analysis, we submit that each of the 3 variants is a probable pathogenic cause of the hereditary hemolytic conditions in these patients. We hope other pediatric practitioners caring for neonates with what appears to be idiopathic severe neonatal hyperbilirubinemia will look for spectrin variants as a possible cause, because additional cases with these specific variants along with this clinical phenotype are needed to confirm our postulate that these 3 cases are indeed pathogenic mutations.
Subject(s)
Elliptocytosis, Hereditary/genetics , Jaundice, Neonatal/genetics , Mutation/genetics , Spectrin/genetics , Spherocytosis, Hereditary/complications , Adult , Elliptocytosis, Hereditary/complications , Female , Humans , Infant, Newborn , Jaundice, Neonatal/complications , Jaundice, Neonatal/therapy , Male , PhototherapyABSTRACT
In an iron deficient child, oral iron repeatedly failed to improve the condition. Whole exome sequencing identified one previously reported plus two novel mutation in the TMPRSS6 gene, with no mutations in other iron-associated genes. We propose that these mutations result in a novel variety of iron-refractory iron deficiency anemia.
Subject(s)
Anemia, Iron-Deficiency/genetics , Membrane Proteins/genetics , Mutation , Serine Endopeptidases/genetics , Alleles , Amino Acid Substitution , Anemia, Iron-Deficiency/diagnosis , Anemia, Iron-Deficiency/drug therapy , Anemia, Iron-Deficiency/metabolism , Biomarkers , Blood Cell Count , DNA Mutational Analysis , Erythrocyte Indices , Female , Genetic Association Studies , Genetic Predisposition to Disease , Genotype , Humans , Infant , Whole Genome SequencingABSTRACT
PURPOSE OF REVIEW: As in adults and older children, anemia in newborn infants can be the result of erythropoietic failure, hemorrhage, or hemolysis. When hemolysis is the prime consideration, it can be challenging for physicians caring for neonates to choose from the wide variety of available diagnostic tests. This review describes the authors' opinions regarding rational, consistent, and cost-effective means of making an exact diagnosis of a neonatal hemolytic condition. RECENT FINDINGS: Two recent advances in the diagnosis of neonatal nonimmune hemolytic disorders are highlighted in this review: introduction of flow cytometry-based Eosin-5-maleimide (EMA) uptake as a screening test to identify RBC membrane defects and next-generation sequencing (NGS)-based panels to uncover exact mutations causing hemolysis. SUMMARY: The availability of newer tools such as EMA and NGS to diagnose specific hemolytic conditions, which might otherwise remain unknown, enables neonatal practitioners not only to identify the exact cause of hemolysis but also to discover novel mutations that can be implicated in the cause of neonatal hemolytic processes.
Subject(s)
Anemia, Hemolytic, Congenital/diagnosis , Anemia, Hemolytic, Congenital/blood , Anemia, Hemolytic, Congenital/etiology , Biomarkers/blood , Flow Cytometry , Genetic Markers , Humans , Infant, Newborn , Mutation , Sequence Analysis, DNA/methodsSubject(s)
Down Syndrome/diagnosis , Hydrops Fetalis/diagnosis , Leukemoid Reaction/diagnosis , Adult , Blood Cell Count/methods , Down Syndrome/complications , Down Syndrome/therapy , Exchange Transfusion, Whole Blood/methods , Female , Humans , Hydrops Fetalis/therapy , In Situ Hybridization, Fluorescence/methods , Infant, Newborn , Leukemoid Reaction/complications , Leukemoid Reaction/therapy , Male , Pregnancy , Pregnancy Complications/diagnosis , Pregnancy Complications/therapyABSTRACT
Symptomatic ß-thalassemia is one of the globally most common inherited disorders. The initial clinical presentation is variable. Although common hematological analyses are typically sufficient to diagnose the disease, sometimes the diagnosis can be more challenging. We describe a series of patients with ß-thalassemia whose diagnosis was delayed, required bone marrow examination in one affected member of each family, and revealed ringed sideroblasts, highlighting the association of this morphological finding with these disorders. Thus, in the absence of characteristic congenital sideroblastic mutations or causes of acquired sideroblastic anemia, the presence of ringed sideroblasts should raise the suspicion of ß-thalassemia.
Subject(s)
Anemia, Sideroblastic/pathology , Bone Marrow Cells/pathology , Erythroblasts/pathology , beta-Thalassemia/pathology , Adolescent , Adult , Anemia, Sideroblastic/diagnosis , Bone Marrow Cells/cytology , Bone Marrow Examination , Child , Erythroblasts/cytology , Erythrocytes, Abnormal , Female , Hematologic Diseases/complications , Humans , Infant , Male , beta-Thalassemia/diagnosisABSTRACT
Hereditary haemolytic anaemias are genetically and phenotypically heterogeneous disorders characterized by increased red cell destruction, with consequences ranging from innocuous to severe life-threatening anaemia. Diagnostic laboratories endeavour to assist clinicians reach the exact patient diagnosis by using tests principally based on morphological and biochemical techniques. However, these routine studies may be inconclusive, particularly in newborn infants and when transfusions have recently been administered. Large numbers and size of the potentially involved genes also impose a practical challenge for molecular diagnosis using routine sequencing approaches. To overcome these diagnostic shortcomings, we have utilized next-generation sequencing to provide a high-throughput, highly sensitive assay. We developed a panel interrogating 28 genes encoding cytoskeletal proteins and enzymes with sequencing coverage of the coding regions, splice site junctions, deep intronic and regulatory regions. We then evaluated 19 samples, including infants with unexplained extreme hyperbilirubinaemia and patients with transfusion-dependent haemolytic anaemia. Where possible, inheritance patterns of pathogenic mutations were determined by sequencing of immediate relatives. We conclude that this next-generation sequencing panel could be a cost-effective approach to molecular diagnosis of hereditary haemolytic anaemia, especially when the family history is uninformative or when routine laboratory testing fails to identify the causative haemolytic process.
Subject(s)
Anemia, Hemolytic, Congenital/diagnosis , High-Throughput Nucleotide Sequencing/methods , Adolescent , Adult , Anemia, Hemolytic, Congenital/genetics , Child , Child, Preschool , Cytoskeletal Proteins/genetics , Enzymes/genetics , Gene Components/genetics , High-Throughput Nucleotide Sequencing/economics , Humans , Hyperbilirubinemia, Hereditary/diagnosis , Infant , Infant, Newborn , Molecular Diagnostic Techniques/economics , Molecular Diagnostic Techniques/methods , Mutation , Young AdultABSTRACT
Siblings presented as neonates with severe jaundice and transfusion-dependent hemolytic anemia. Next-generation sequencing revealed both to have three heterozygous mutations in the gene encoding erythrocyte pyruvate kinase (PKLR), plus a heterozygous splice mutation in the beta-spectrin gene (SPTB). In addition, both have a different 5th mutation in a gene encoding other erythrocyte membrane proteins. The asymptomatic parents and all three asymptomatic siblings have different sets of these mutations. © 2016 Wiley Periodicals, Inc.
Subject(s)
Genetic Association Studies , Genotype , Pyruvate Kinase/deficiency , Pyruvate Kinase/genetics , Siblings , Biomarkers , Female , High-Throughput Nucleotide Sequencing , Humans , Infant, Newborn , Mutation , Pedigree , Phenotype , Polymorphism, GeneticABSTRACT
Hemolysis can be an important cause of hyperbilirubinemia in premature and term neonates. It can result from genetic abnormalities intrinsic to or factors exogenous to normal to red blood cells (RBCs). Hemolysis can lead to a relatively rapid increase in total serum/plasma bilirubin, hyperbilirubinemia that is somewhat slow to fall with phototherapy, or hyperbilirubinemia that is likely to rebound after phototherapy. Laboratory methods for diagnosing hemolysis are more difficult to apply, or less conclusive, in preterm infants. Transfusion of donor RBCs can present a bilirubin load that must be metabolized. Genetic causes can be identified by next-generation sequencing panels.