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)

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

A 31-yr-old female with congenital hypoplastic anemia (Diamond-Blackfan syndrome) whose long course terminated in acute myelogenous leukemia is described. In contrast to Fanconi anemia, malignant transformation rarely occurs in congenital hypoplastic anemia. This patient's diagnosis of congenital hypoplastic anemia is supported by her clinical course, absence of renal abnormalities, a negative family history for hematologic disorders, normal chromosome studies, failure of her skin fibroblasts to transform in culture with SV-40 virus, macrocytic erythrocyte indices, erythrocyte enzyme studies, and bone marrow findings. Only two other cases of malignancy have been reported in patients with congenital hypoplastic anemia. The development of malignancy in these patients suggests that malignant transformation may be a concern in the long-term progression of congenital hypoplastic anemia.
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PMID:Congenital hypoplastic anemia (Diamond-Blackfan syndrome) terminating in acute myelogenous leukemia. 27 51

A 24-year-old woman had congenital hypoplastic anemia (Blackfan-Diamond syndrome). Anemia was discovered at the age of 12 months and persisted thereafter. The patient had associated congenital abnormalities of urethral stricture, hypoplastic thumb, and absent radial pulse. Her erythroid hypoplasia responded favorably to treatment with prednisone.
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PMID:Prednisone-responsive congenital erythroid hypoplasia. 57 54

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

The profound anemia of Diamond-Blackfan syndrome (DBS) is due to marrow red cell failure, but the pathogenesis is not understood. Studies by others indicated cell-mediated erythropoietic suppression in this condition. To explore this mechanism further, Ficoll-Hypaque--separated peripheral blood lymphocytes (PBL) from four anemic untreated patients with DBS, or from normals were cocultured with control marrow in vitro and the growth of erythropoietin-responsive stem cell colonies (CFU-E) was dermined. CFU-E numbers obtained from cultures with added normal PBL were not significantly different from the number without PBL. Similarly, CFU-E from cultures with added DBS PBL were not significantly different from the number without PBL (215 versus 220, 229 versus 220 and 84 versus 60, 74 versus 94/10(5) cells, respectively). Mixing marrows from a control and one DBS patient in ratios of 2:1, 1:1, or 1:2 prior to culture failed to disclose a decrease of colony growth. We could not show cellular inhibition of erythropoiesis in these patients with DBS. The mechanism of anemia in this disorder remains an open question.
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PMID:Diamond-Blackfan syndrome: evidence against cell-mediated erythropoietic suppression. 64 16

A 19-year-old patient with congenital Blackfan-Diamond anaemia has been maintained on a regular red cell transfusion schedule since he was two months old. From the age of four he has received desferrioxamine injections at regular intervals with different dose levels. In spite of the treatment with the chelating agent secondary siderosis developed with typical endocrinological abnormalities and cardiac arrhythmias. Increasing the dose of desferrioxamine to 16 g/24 h resulted in an iron excretion of 184 mg/24 h. Such an intensification of treatment finally produced a negative iron balance and the cardiac arrhythmias disappeared. Desferrioxamine therapy should be done under controlled circumstances only, an iron balance is mandatory, and the dose should be adjusted to the results of the balance.
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PMID:[Controlled desferrioxamine treatment of congenital anaemia and transfusion siderosis (author's transl)]. 66 72

The effect of varying the H-2 complex on the survival of parabiosed mice was investigated using a strain combination known to lead to about 50% long-term survival. While 45.6% of DBA/2J (H-2d) with (DBA/2J x C3H/HeJ)F1 (H-2d/H-2k) parabionts survive to 100 days or more, 69% of DBA/2J with (DBA/2J x C3H.NBSn)F1s (H-2d/H-2p) survive that long; only 16% of DBA/2J with (DBA/2Jx C3H.SWSn)F1s (H-2d/H-2b) survive to 100 days. The plot of hematocrits as a function of time after parabiosis differs significantly between the 45.6% surviving strain combination (which shows the classical pattern of parental polycythemia and F1 hybrid anemia) and the 69% surviving strain combination (which shows no divergence in parental and F1 hematocrit values). Furthermore, the 69% surviving strain combination often (5/14) persists in a chimeric state as judgec by starch gel electrophoresis of rec blood cell lysates; the other two strain combinations show no demonstrable red cell chimerism. The conclusion is suggested that the mechann these two generally successful strain combinations tested, and appears to be a function of the H-2types of the partners.
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PMID:The genetics of tolerance induction in histoincompatible parabiosed mice. 98 44

Six cases of Blackfan-Diamond hypoplastic anemia are reported. Five were initiated within six months of life. All cases showed intense anemia, severe reticulopenia and hypersideremia. Two of them had associated malformations. Treatment was established with Dexametasone at high doses, followed by a maintenance treatment at lower doses. A partial response was obtained in all cases. Treatment with deforroxiamine was used in order to paliate hemosiderosis. Two cases developped microangiopathic hemolitic anemia; relations with primary disease could not be determined.
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PMID:[Long term evolution in Blackfan-Diamond hypoplastic anemia (author's transl)]. 98

The response of bone marrow to erythropoietin (EPO) from five children with the Diamond-Blackfan syndrome, also known as congenital hypoplastic anaemia (CHA), was tested in tissue culture by measurement of haem synthesis. Studies of 13 control marrows indicated that the maximum EPO effect occurred at approximately 70 h incubation using an EPO concentration of 0.2-0.3 units/ml and a nucleated cell concentration of 5 x 10(6) per culture. Under these conditions, haem synthesis was 121% greater in EPO-stimulated than in unstimulated cultures. Patients with CHA with anaemia and diminished marrow erythroids had reduced or absent haem synthesis. In one patient, haem production became normal after a spontaneous remission, and was not inhibited by autologous plasma drawn at the time of diagnosis. Plasma from three patients did not show inhibitory activity when cultured with control marrow. In contrast, plasma from an adult with acquired pure red cell aplasia produced striking inhibition of haem synthesis when cultured with control marrow. We conclude that, in comparison to some cases of the adult acquired condition, CHA is not due to inhibitors or antibodies. When present, erythroid precursors in children with CHA are capable of responding normally to EPO with increased haem synthesis.
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PMID:Haem synthesis in the Diamond-Blackfan syndrome. 123 7

Four children with congenital hypoplastic anemia (Diamond-Blackfan syndrome) and 30 control children with normal erythropoiesis were studied by a cell culture method in which human marrow, grown in a plasma clot, responds to added erythropoietin (EPO) with the appearance of discrete colonies of nucleated erythroid cells. The colonies arise from EPO-responsive stem cells and are not related to the number of morphologically identifiable marrow erythroids plated. Results of studies on control marrow indicated that without EPO there was little or no colony formation. Increasing EPO doses or nucleated marrow cells per culture resulted in a linear increase in colony numbers. The optimal EPO concentration of 2.5 U/ml yielded a mean of 158 +/- 79 colonies/1 x 10(5) nucleated cells on day 7 of incubation. Even in the absence of recognizable erythroids, marrows of all four patients with anemia grew erythroid colonies. Two patients on no therapy had decreased colony numbers. The other two, on prednisone, had normal numbers. Sera from patients did not inhibit colony formation from either autologous or control marrow. In contrast, serum from an adult with acquired pure red cell aplasia produced striking inhibition of colony growth. It appears that the red cell failure in this disorder is not due to an absence of erythroid stem cells, and a serum inhibitor to erythropoiesis as seen in the acquired disease is unlikely.
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PMID:Erythroid colony growth in congenital hypoplastic anemia. 124 3


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