Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002874 (aplastic anemia)
 5,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fetal erythropoiesis occurs during chronic bone marrow failure, or during recovery from marrow suppression. Fetal erythrocytes have HB F, with more G gamma than A gamma chains, "i" antigen, large MCV, characteristic enzyme levels, low carbonic anhydrase, low HB A2, and short life span. Many of these fetal characteristics are present in the red cells of patients with temporary or chronic hematopoietic stress. In those in whom normal hematopoiesis ensues, the fetal erythrocytes disappear. The fetal phase of recovery may be with homologous stem cells after bone marrow engraftment, or with autologous cells. Chronic fetal erythropoiesis is seen in patients with constitutional aplastic anemia, such as Fanconi's anemia or Diamond-Blackfan anemia. In one patient with the latter disorder, fetal erythropoiesis accompanied chronic anemia, and actually decreased slightly during the acute phase of clinical improvement. Culture of late erythroid precursor cells (CFU-Es) from a patient with transient erythroblastopenia of childhood led to in vitro development of colonies with HB F, an event not seen in normal marrow cultures. Thus fetal erythropoiesis occurs during hematopoietic stress, whether chronic or transient, if there is some marrow activity, and may be due to expansion of fetal clones.
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PMID:Fetal erythropoiesis in stress hematopoiesis. 9 16

Congenital (constitutional) aplastic anemias in children are relatively rare compared to other diseases but as their outcome is nearly always fatal they are given full attention in pediatric-hematological literature. Although in many patients the number of white cells and thrombocytes as well as of red cells is diminished even in the first phase of the disease (or later in the course of the disease) so that these diseases are really pancytopenias, the term most frequently used to describe these clinical entities is aplastic anemia. The clinical and hematological characteristics of some aplastic anemias (Fanconi's anemia, Blackfan-Diamond's anemia, congenital dyserythropoietic anemia--type I, II, III and IV, etc.) are described. After considering the possible pathomechanisms which bring about aplastic anemia (pancytopenia), information is given about the method of treatment and prognostic prospects with reference to cases treated by the authors.
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PMID:[Congenital aplastic anemias]. 61 96

In inbred mice strain DBA/2, genetically controlled differences in aryl hydrocarbon hydroxylase (AHH) activity have been demonstrated that predispose to aplastic anemia. To test the hypothesis of a similar mechanism in humans, we studied the formation of benzo(a)pyrene DNA adducts and water-soluble metabolites in skin fibroblasts from eight patients with aplastic anemia and eight normal controls. The ratio of water-soluble metabolites and DNA adducts was 46.5 +/- 16.6 in patients and was significantly lower as compared to 82.9 +/- 38.5 in controls (P less than 0.05). We conclude that increased formation of genotoxic intermediates may be a pathogenetic mechanism in some patients with aplastic anemia.
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PMID:Increased formation of DNA adducts in cultured fibroblasts of patients with aplastic anemia after in vitro incubation with benzo(a)pyrene. 228 25

We treated 22 patients with severe aplastic anaemia refractory to antithymocyte globulin (ATG) with cyclosporine, alone or in combination with prednisone. Eight patients showed significant clinical improvement, all but one to transfusion-independence. Although cyclosporine alone was effective, the addition of prednisone resulted in prompter and fuller haematologic improvement. No patient with an absolute granulocyte count less than 0.2 x 10(9)/l responded to treatment. Haematologic remissions were sustained beyond the treatment period. Of nine patients with Diamond-Blackfan syndrome, one showed a complete response to two separate courses of cyclosporine and relapse with withdrawal of therapy, and a second achieved significant reduction in corticosteroid dose without relapse; however, seven cases failed to respond. Two of three adults with acquired pure red cell aplasia recovered. A combination of cyclosporine and corticosteroids may be effective therapy in patients with aplastic anaemia who have failed ATG treatment. Occasional cases of congenital and acquired pure red cell aplasia may also respond to cyclosporine.
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PMID:Cyclosporine therapy of aplastic anaemia, congenital and acquired red cell aplasia. 251 70

Renal lesions found in 21 autopsied patients with hemosiderosis, 18 with beta-thalassemia, two with Blackfan-Diamond anemia, and one with aplastic anemia included: cellular glomeruli with increased mesangial matrix; hemosiderin deposit in visceral and parietal glomerular epithelial cells; greater hemosiderin deposit in terminal straight portions of proximal convoluted tubules and distal convoluted tubules than in connecting segments, or collecting tubules, connective tissue ferrugination; lipofuscin in tubular epithelium and vascular smooth muscle; infrequently, intimal or medial arterial thickening, and, in one patient with thalassemia, an infarct resulting from arterial thrombus. The progression of these lesions over the course of disease, and possible effects on the various lesions of high transfusion regimen, oral pancreatin, vitamin E supplementation, or treatment with intramuscular, subcutaneous, or intravenous desferrioxamine were evaluated. The results of urine and renal function studies of 4 of the autopsied patients (3 thalassemia, 1 Blackfan-Diamond anemia), and 14 patients with thalassemia and 4 with Blackfan-Diamond anemia who were not autopsied, are presented. Rarely significant until preterminal stages, the renal functional changes reflect distal more than proximal tubule dysfunction.
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PMID:Renal lesions and clinical findings in thalassemia major and other chronic anemias with hemosiderosis. 201 91

Marrow transplantation is effective treatment for a number of hematological diseases in patients under the age of 50 who have an HLA-identical sibling donor. It is successful in the treatment of aplastic anemia with 70-85% long-term survival. It offers 10-30% apparent cures for patients with acute leukemia who have relapsed at least once, and for those with chronic myelocytic leukemia in blast crisis. Although still somewhat controversial, it appears to be the treatment of choice for patients with acute nonlymphoblastic leukemia in first chemotherapy induced remission, and for those with chronic myelogenous leukemia in the chronic phase since approximately 50-60% of these patients experience long-term, disease-free survival. Patients with acute lymphoblastic leukemia grafted in second or subsequent remission may expect a 30% "cure" of their disease. Marrow grafting is the only effective treatment for many patients with inherited immunologic deficiencies and certain genetic storage diseases. Cures of congenital Fanconi's anemia, Blackfan-Diamond anemia, osteopetrosis, paroxysmal nocturnal hemoglobinuria and thalassemia major have been achieved. Marrow transplantation is being explored for the therapy of patients with lymphoma, Hodgkin's disease, preleukemia, multiple myeloma, hairy cell leukemia, small cell lung cancer, testicular cancer, ovarian cancer and neuroblastoma. Marrow transplantation has been limited by the fact that many patients do not have HLA-identical siblings and very few have monozygotic twins. More recently, marrow transplants from HLA-nonidentical family members and even from unrelated donors have been successfully explored.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Marrow transplantation: the Seattle experience. 391 47

Marrow transplantation is effective treatment for a number of haematological diseases in patients under the age of 50 who have an HLA-identical sibling donor. It is generally successful when used early in the treatment of aplastic anaemia. It is the only treatment that offers long-term disease-free survival for patients with acute leukaemia who have relapsed at least once, with 10-30 per cent apparent cures. Although still somewhat controversial, it appears also to be the treatment of choice for patients with acute non-lymphoblastic leukaemia in first chemotherapy induced remission and for those with chronic myelogenous leukaemia in the chronic phase since approximately 50-60 per cent of these patients are surviving after marrow transplantation in complete remission, apparently cured. Marrow grafting is the only effective treatment for many patients with inherited immunological-deficiency diseases and certain genetic storage diseases. It is being explored for the therapy of patients with lymphoma, Hodgkin's disease, multiple myeloma, small-cell lung cancer, testicular cancer, ovarian cancer and genetic disorders of haematopoiesis. Cures of congenital Fanconi anaemia, Blackfan-Diamond anaemia, osteopetrosis, and paroxysmal nocturnal haemoglobinuria have been achieved by marrow grafting. Genetic disorders associated with haemolytic anaemia and cyclic neutropenia have been cured by marrow grafting in animals. Target disorders for marrow transplantation in humans are thalassaemia major and sickle cell disease, and, indeed, a first successful transplant for treatment of thalassaemia major has recently been described (Thomas et al, 1982). Marrow transplantation has been limited by the fact that many patients do not have HLA-identical siblings and very few have monozygotic twins. The Seattle team has now explored the use of less well-matched family member donors in more than 80 patients with leukaemia. These donors share one HLA haplotype genetically with the patient and are phenotypically identical at two of the three major HLA loci on the other HLA haplotype (Clift et al, 1979). Overall, the post-transplant survival appears more a reflection of the type and stage of the leukaemia than of the marrow donor. Patients with leukaemia grafted in relapse have a projected survival of 20-30 per cent and those transplanted in remission of 50 per cent. The incidence and severity of GVHD may not be significantly different from that of patients given HLA-identical sibling marrow grafts.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Application of bone marrow transplantation in leukaemia and aplastic anaemia. 635 79

A number of studies have demonstrated that certain immunocompetent cells play a role in the regulation of normal erythropoiesis. These regulatory cells (monocytes--macrophages, lymphocytes) modulate almost every phase of the erythropoietic process, and along with erythropoietin represent the major controlling force in erythropoiesis. Evidence indicate that pathological alterations of these cell-mediated activities can lead to clinical disturbances of red cell production such as is seen in patients with Diamond-Blackfan syndrome and aplastic anemia.
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PMID:Role of cell--cell interaction in normal and abnormal erythropoiesis. 644 59

Abnormalities of adenosine deaminase, a critical enzyme of the purine salvage pathway, have been reported in association with immune dysfunction, acute leukemia, and hereditary hemolytic anemia. We report data showing that erythrocyte adenosine deaminase activity is also abnormal in congenital hypoplastic anemia (the Diamond-Blackfan syndrome). Adenosine deaminase activity in erythrocytes from 12 patients (mean +/- S.D., 2.20 +/- 0.77 IU per gram of hemoglobin) was substantially greater than that observed in 50 controls (0.62 +/- 0.13 IU per gram). Enzyme activity in affected patients was also greater than that seen in cord blood or in erythrocytes from patients with hemolytic anemia, acquired aplastic anemia, Fanconi's hypoplastic anemia, acquired pure red-cell aplasia, or transient erythroblastopenia of childhood. These observations indicate that erythrocyte adenosine deaminase activity may be a unique marker for identifying congenital hypoplastic anemia.
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PMID:Elevated erythrocyte adenosine deaminase activity in congenital hypoplastic anemia. 664 73

The expression of fetal characteristics of erythropoiesis (haemoglobin F concentration, haemoglobin A2 concentration, haemoglobin F cells, globin chain synthesis, carboanhydrase isoenzyme B, hexokinase isoenzymes, erythrocyte membrane antigens of the iI- and the ABH-system) was examined in red cells of twelve patients with different bone marrow disorders (juvenile chronic myeloid leukaemia (JCML), erythroleukaemia (EL), acute myelogenous leukaemia (AML), aplastic anaemia (AA) and Diamond-Blackfan anaemia (DB)). In JCML and EL all red cell parameters studied appeared to be fetal including the distribution of hexokinase isoenzymes. No fetal signs could be found in red cells of patients with AML. In two patients with DB who were treated by transfusion no fetal erythropoiesis could be detected. In one patient with DB under cortisone treatment i-antigen, ABH-antigens, haemoglobin F concentration, globin chain synthesis and hexokinase isoenzyme distribution were of the fetal or mixed type. In patients with AA only slight elevations of haemoglobin F were detectable. The nearly total reversion to fetal erythropoiesis in JCML and EL seems to be a part of the disorder itself, whereas in the other disorders the reactivation of fetal erythropoiesis could be the result of an erythropoietic stress.
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PMID:The pattern of reactivated fetal erythropoiesis in bone marrow disorders of childhood. 696 27


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