Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This review summarizes the biology of thrombopoietin (TPO) in childhood. Studies on TPO and its receptor (c-mpl) have improved the understanding of inherited and acquired thrombocytopenias in childhood. Data are presented in this review regarding the molecular biology of TPO, differences in cellular effects on megakaryopoiesis, the regulation of TPO production, and TPO concentrations in health and disease. For neonatal thrombocytopenia, the focus is on early-onset thrombocytopenia associated with maternal diabetes, pregnancy-induced hypertension, intrauterine growth retardation, hypoxia, and sepsis. Fetal alloimmune thrombocytopenia allows insight into the biology of TPO when fetal megakaryopoiesis is chronically stimulated. In the thrombocytopenia absent radii syndrome and congenital amegakaryocytic thrombocytopenia, thrombocytopenia is caused by a disorder in the signal transduction at the c-mpl level and respectively directly on c-mpl. TPO concentrations in other inherited thrombocytopenias such as Fanconi anemia, Shwachman syndrome, Wiskott-Aldrich syndrome, and Bernard-Soulier syndrome are discussed. For acquired thrombocytopenias, data on TPO in aplastic anemia, immune thrombocytopenia, human immunodeficiency virus infection, and liver disease are given. Possible indications for a treatment with recombinant TPO in childhood are discussed, but the criteria to identify patients who would benefit need detailed evaluation.
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PMID:Thrombopoietin in thrombocytopenias of childhood. 1144 55

The bone marrow failure syndromes consist of a number of rare diseases, in which there is ineffective hematopoiesis by the bone marrow. Subsequently, absent or decreased production of a single cell line, single cytopenia, or of all cell lines, and pancytopenia, develops. The mechanisms of hematopoiesis and the defects that result in bone marrow failure are beginning to be better understood. This paper will review the genetic and molecular basis of several important bone marrow failure syndromes in children, Fanconi anemia, Shwachman-Diamond syndrome, Diamond-Blackfan anemia, congenital amegakaryocytic thrombocytopenia, dyskeratosis congenita, and severe congenital neutropenia, and the recent discoveries that have enhanced our understanding of the pathogenesis of these diseases.
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PMID:The genetic basis of bone marrow failure syndromes in children. 1612 92

Prompt and accurate diagnosis is required for optimal treatment and genetic counseling of patients with inherited bone marrow failure syndromes (IBMFS). However, the diverse clinical picture of these syndromes and their rareness is often associated with diagnostic difficulties. Recently, an improved diagnostic approach is possible by the cloning of many of the causative genes. Fanconi anemia (FA) patients belong to at least 12 complementation groups, of which 11 genes have been cloned. An approach combining an induced chromosomal breakage test, detection of FANCD2-L by Western blot analysis, complementation group analysis, and detailed mutation analysis enables unraveling the causative mutation in the majority of patients. With the use of such strategies, genotype/phenotype correlations in FA are evolving. In dyskeratosis congenita mutations in DCK1, TERC, and TERT genes have been identified, but mutations have been found in less than half of these patients. In patients with Shwachman-Diamond syndrome, mutations in the SBDS gene were found in approximately 90% of patients. In Diamond-Blackfan anemia the RSP19 gene is mutated in 20-25% of patients. Heterozygote ELA2 mutations are found in 60-80% of severe congenital neutropenia patients. All patients with congenital amegakaryocytic thrombocytopenia have mutations in the thrombopoietin receptor gene c-Mpl.
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PMID:Current diagnosis of inherited bone marrow failure syndromes. 1745 74

Inherited diseases and metabolism inborn errors with hematologic abnormalities such as cytopenias are observed early in the infant or childhood. Most of them require an acute observation of the bone marrow to determine quantitative and qualitative morphological peculiarities of each cell line in order to charatherize cytological signs of these childhood hereditary diseases and differentiate them from acquired disorders, which are particularly frequent in pediatric. So, after a brief review of hematopoietic physiology in healthy neonates and infant, we'll consider the physiopathology and bone marrow aspect of the erythroid (Blackfan-Diamond anemia, congenital dyserythropoietic...), megacaryocytic (Wiskott-Aldrich syndrome, congenital amegakaryocytic thrombocytopenia...) and granulocytic cell line (Kostmann syndrome, WHIM syndrome...) in hereditary disorder. Considering the hematologic consequences of metabolism inborn errors and storage diseases, the last part of this review will be dedicated to the examination of the bone marrow encountered in those diseases such as mitochondrial cytopathy, orotic aciduria or lysinuric aciduria intolerance.
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PMID:[Bone marrow examination of inherited diseases in children]. 1791 68

An important indication for bone marrow investigation is the presence of bone marrow failure, which manifests itself as (pan)cytopenia. The causes of cytopenia are varied and differ considerably between childhood and adulthood. In the paediatric age group inherited bone marrow failure syndromes are important causes of bone marrow failure, but they play only a minor role in later life. This review gives a comprehensive overview of bone marrow failure disorders in children and adults. We classified the causes of bone marrow failure according to the main presenting haematological abnormality, i.e. anaemia, neutropenia, thrombocytopenia or pancytopenia. The following red cell disorders are discussed: red cell aplasia, sideroblastic anaemia, congenital dyserythropoietic anaemia, haemolytic anaemia, paroxysmal nocturnal haemoglobinuria, iron deficiency anaemia, anaemia of chronic disease and megaloblastic anaemia. The neutropenias occur in the context of Shwachman-Diamond syndrome (SDS), severe congenital neutropenia, cyclic neutropenia, immune-related neutropenia and non-immune neutropenia. In addition, the following causes of thrombocytopenia are discussed: congenital amegakaryocytic thrombocytopenia, thrombocytopenia with absent radii, immune-related thrombocytopenia and non-immune thrombocytopenia. Finally, we pay attention to the following pancytopenic disorders: Fanconi anaemia, dyskeratosis congenita, aplastic anaemia, myelodysplastic syndromes and human immunodeficiency virus (HIV) infection.
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PMID:The pathology of bone marrow failure. 2072 24

We observed a neonate with severe congenital thrombocytopenia and features of Noonan syndrome where evaluations were negative for immune-mediated thrombocytopenia, congenital infections, and Fanconi anemia. The marrow findings and a significantly elevated plasma thrombopoietin (Tpo) level were consistent with congenital amegakaryocytic thrombocytopenia; we sought a genetic mutation that could explain this phenotype. No mutations were identified in c-MPL (the Tpo receptor gene). Microarray analysis of peripheral blood did not reveal an abnormality. DNA sequencing of the PTPN11 gene showed a heterozygous C>T nucleotide substitution in exon 3 (c.218C>T) predicted to result in a threonine-to-isoleucine change at residue 73 (T73I). A 6-week trial of eltrombopag (an agonist of the Tpo receptor) failed to increase the platelet count. We propose this specific PTPN11 mutation results in abnormalities of the protein product SHP-2, which, because of its role in signal transduction, results in severe congenital thrombocytopenia refractory to c-MPL agonists.
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PMID:A de novo T73I mutation in PTPN11 in a neonate with severe and prolonged congenital thrombocytopenia and Noonan syndrome. 2344 78

Peripheral blood cytopenia in children can be due to a variety of acquired or inherited diseases. Genetic disorders affecting a single hematopoietic lineage are frequently characterized by typical bone marrow findings, such as lack of progenitors or maturation arrest in congenital neutropenia or a lack of megakaryocytes in congenital amegakaryocytic thrombocytopenia, whereas antibody-mediated diseases such as autoimmune neutropenia are associated with a rather unremarkable bone marrow morphology. By contrast, pancytopenia is frequently associated with a hypocellular bone marrow, and the differential diagnosis includes acquired aplastic anemia, myelodysplastic syndrome, inherited bone marrow failure syndromes such as Fanconi anemia and dyskeratosis congenita, and a variety of immunological disorders including hemophagocytic lymphohistiocytosis. Thorough bone marrow analysis is of special importance for the diagnostic work-up of most patients. Cellularity, cellular composition, and dysplastic signs are the cornerstones of the differential diagnosis. Pancytopenia in the presence of a normo- or hypercellular marrow with dysplastic changes may indicate myelodysplastic syndrome. More challenging for the hematologist is the evaluation of the hypocellular bone marrow. Although aplastic anemia and hypocellular refractory cytopenia of childhood (RCC) can reliably be differentiated on a morphological level, the overlapping pathophysiology remains a significant challenge for the choice of the therapeutic strategy. Furthermore, inherited bone marrow failure syndromes are usually associated with the morphological picture of RCC, and the recognition of these entities is essential as they often present a multisystem disease requiring different diagnostic and therapeutic approaches. This paper gives an overview over the different disease entities presenting with (pan)cytopenia, their pathophysiology, characteristic bone marrow findings, and therapeutic approaches.
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PMID:Missing Cells: Pathophysiology, Diagnosis, and Management of (Pan)Cytopenia in Childhood. 2621 51

Bone marrow failure and related syndromes are rare disorders characterized by ineffective bone marrow hematopoiesis and peripheral cytopenias. Although many are associated with characteristic clinical features, recent advances have shown a more complicated picture with a spectrum of broad and overlapping phenotypes and imperfect genotype-phenotype correlations. Distinguishing acquired from inherited forms of marrow failure can be challenging, but is of crucial importance given differences in the risk of disease progression to myelodysplastic syndrome, acute myeloid leukemia, and other malignancies, as well as the potential to genetically screen relatives and select the appropriate donor if hematopoietic stem cell transplantation becomes necessary. Flow cytometry patterns in combination with morphology, cytogenetics, and history can help differentiate several diagnostic marrow failure and/or insufficiency entities and guide genetic testing. Herein we review several overlapping acquired marrow failure entities including aplastic anemia, hypoplastic myelodysplasia, and large granular lymphocyte disorders; and several bone marrow disorders with germline predisposition, including GATA2 deficiency, CTLA4 haploinsufficiency, dyskeratosis congenita and/or telomeropathies, Fanconi anemia, Shwachman-Diamond syndrome, congenital amegakaryocytic thrombocytopenia, severe congenital neutropenia, and Diamond-Blackfan anemia with a focus on advances related to pathophysiology, diagnosis, and management.
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PMID:Acquired and germline predisposition to bone marrow failure: Diagnostic features and clinical implications. 3057 48

Inherited bone marrow failure syndromes are experiments of nature characterized by impaired hematopoiesis with cancer and leukemia predisposition. The mutations associated with inherited bone marrow failure syndromes affect fundamental cellular pathways, such as DNA repair, telomere maintenance, or proteostasis. How these disturbed pathways fail to produce sufficient blood cells and lead to leukemogenesis are not understood. The rarity of inherited cytopenias, the paucity of affected primary human hematopoietic cells, and the sometime inadequacy of murine or induced pluripotential stem cell models mean it is difficult to acquire a greater understanding of them. Zebrafish offer a model organism to study gene functions. As vertebrates, zebrafish share with humans many orthologous genes involved in blood disorders. As a model organism, zebrafish provide advantages that include rapid development of transparent embryos, high fecundity (providing large numbers of mutant and normal siblings), and a large collection of mutant and transgenic lines useful for investigating the blood system and other tissues during development. Importantly, recent advances in genomic editing in zebrafish can speedily validate the new genes or novel variants discovered in clinical investigation as causes for marrow failure. Here we review zebrafish as a model organism that phenocopies Fanconi anemia, Diamond-Blackfan anemia, dyskeratosis congenita, Shwachman-Diamond syndrome, congenital amegakaryocytic thrombocytopenia, and severe congenital neutropenia. Two important insights, provided by modeling inherited cytopenias in zebrafish, widen understanding of ribosome biogenesis and TP53 in mediating marrow failure and non-hematologic defects. They suggest that TP53-independent pathways contribute to marrow failure. In addition, zebrafish provide an attractive model organism for drug development.
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PMID:Peering through zebrafish to understand inherited bone marrow failure syndromes. 3057 10