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

The red blood cell distribution width (RDW) has been proposed as an additional variable that would improve the initial classification of anemia. Microcytic anemias with an elevated RDW (greater heterogeneity) were used to distinguish iron deficiency from heterozygous thalassemia, which was said to have a normal RDW (more homogeneous). The authors attempted to classify their population of microcytic cases using the RDW as a major variable, but found only limited utility. While most of the iron-deficient cases had an increased RDW, almost one-half of the thalassemia cases also were classified as microcytic heterogeneous (increased RDW). The authors also found that target cells, erythrocytosis, and the ratios alone or in combination with the RDW were not specific in separating heterozygous thalassemia from iron deficiency. They conclude that a sequential evaluation (to include iron and hemoglobin studies) of cases of microcytosis is still needed.
 ...
PMID:Limitations of red blood cell distribution width (RDW) in evaluation of microcytosis. 395 99

An English family suffering from thalassaemia minor is described. Three generations are affected, and all the affected members had a considerably raised red cell count in the presence of slight or moderate anaemia, obviously abnormal peripheral films, and only slightly reduced M.C.H.C. values; and each had a moderately raised haemoglobin A(2) level, though foetal haemoglobin levels were normal. The presentation of a family with erythrocytosis recalls the condition described in the older literature as benign familial polycythaemia which was, in some cases at least, thalassaemia minor. It is suggested that the presence of a raised red cell count is a more reliable distinguishing feature than the presence of target cells, or the serum iron level, in thalassaemia minor.
 ...
PMID:Benign familial polycythaemia. 560 7

Blood from patients with erythrocytosis secondary to arterial hypoxemia due either to congenital heart disease or to chronic obstructive pulmonary disease was shown to have a decreased affinity for oxygen; the average oxygen pressure required to produce 50% saturation of hemoglobin with oxygen was 29.8 mm Hg (average normal, 26.3 mm Hg). Such a displacement of the blood oxygen equilibrium curve promotes the release of oxygen from blood to the tissues. Studies were also performed upon blood from a man with complete erythrocyte aplasia who received all of his red cells by transfusion from presumably normal persons. With mild anemia (hematocrit, 28%), the affinity of his blood for oxygen was slightly diminished (an oxygen pressure of 27.0 mm Hg was required to produce 50% saturation of hemoglobin with oxygen). With severe anemia (hematocrit, 13.5%), however, his blood had a markedly decreased oxygen affinity (an oxygen pressure of 29.6 mm Hg was required to produce 50% saturation of hemoglobin with oxygen). We conclude that patients with various conditions characterized by an impairment in the oxygen supply system to tissues respond with a diminished affinity of their blood for oxygen. Although the mechanism which brings about this adaptation is not known, the displacement of the oxygen equilibrium curve is associated with an increase in heme-heme interaction. The decrease in blood oxygen affinity need not occur during erythropoiesis, but may be imposed upon mature circulating red cells.
 ...
PMID:Improved oxygen release: an adaptation of mature red cells to hypoxia. 566 14

A 32-year-old woman with asymptomatic primary biliary cirrhosis had autoimmune hemolytic anemia associated with reticulocytopenia and thrombocytopenia despite an intensely erythroid bone marrow. Her anemia was successfully treated with oral prednisolone and intravenous pulse methylprednisolone, with a rapid response of reticulocytosis and sustained erythrocytosis. Tiopronin therapy was later initiated and resulted in fever, rash, exacerbation of the liver disease, and positive direct and indirect antiglobulin tests.
 ...
PMID:Primary biliary cirrhosis. A patient with adverse reactions to tiopronin and autoimmune hemolytic anemia with reticulocytopenia. 622 29

Anemia of endstage renal failure improves shortly after kidney transplantation. However, in about 10% of transplanted patients polycythemia occurs. By use of a sensitive in vitro bioassay the pathogenetic role of erythropoietin (Ep) was investigated in 12 patients with post-transplant erythrocytosis (PTE), and compared to 12 non-PTE patients. The mean Ep of 160 mU/ml was significantly elevated in patients with PTE as compared to 25 mU/ml of 36 healthy controls, whereas, the mean Ep of 24 mU/ml in non-PTE patients did not differ significantly from healthy controls. To further elucidate the mechanism of inappropriate Ep production, selective venous catheterization of native and transplanted kidneys was performed in six patients. In four PTE patients the mean Ep in native kidney veins of 110 mU/ml was significantly higher than the peripheral Ep of 66 mU/ml, whereas, mean Ep in kidney graft veins was 51 mU/ml. In contrast, in two non-PTE patients no significant difference between mean Ep from native and transplanted kidney veins was observed. We conclude that some patients escape from normal feedback regulation either due to autonomous Ep production or due to feedback regulation at an elevated level of hematocrit and that inappropriate Ep production originates from the diseased native kidneys.
 ...
PMID:Deficient feedback regulation of erythropoiesis in kidney transplant patients with polycythemia. 635 16

Management of hematologic disorders in older patients must often be weighed in a setting of decreased physiological reserves and concurrent illnesses. Anemia in the elderly should never be attributed to old age. Even a mild anemia in collusion with multiple physical and mental problems may tip the balance for those previously able to cope with their disabilities. Iron deficiency anemia and the anemia of chronic disease are the most common types of anemia in the elderly. Nutritional anemias due to folate or vitamin B(12) deficiency are treatable and should not be overlooked. Newer chemotherapy regimens for acute nonlymphocytic leukemia have been effective in many older patients. Decisions to treat are sometimes difficult, often depending on the aggregate of coexistent physical and mental disorders. The most prevalent type of leukemia in the elderly is chronic lymphocytic leukemia. A benign asymptomatic course requires no therapy, but aggressive disease requires treatment. Multiple myeloma should be suspected in an elderly person who has both unexplained anemia and bone pain. After definitive diagnosis, phlebotomy therapy should be considered for both polycythemia vera and secondary erythrocytosis to reduce blood viscosity and increase cerebral blood flow.
 ...
PMID:Hematologic disorders in the elderly. 680 66

The levels of 2,3-DPG and the value of P50 were determined in unselected, clinically healthy, typical beta-thalassemia heterozygotes and normal controls. Values of 2,3-DPG in the heterozygotes are significantly elevated compared to normals (when expressed per gram of hemoglobin or per volume of red cells) and much higher than their mild hemoglobin deficit would explain; they are elevated even in selected heterozygotes presenting normal hemoglobins levels. These 2,3-DPG values, when expressed per number of erythrocytes, are within normal limits. In parallel, oxygen affinity is lower, as the P50 value is displaced to the right by 2 mmHg above the normal mean, thus assuring adequate tissue oxygenation. The findings suggest that the high 2,3-DPG values of the beta-thalassemia heterozygotes are not determined solely by anemic hypoxia; it is more likely that the microcytic erythrocytosis of heterozygous beta-thalassemia is the cause of this increase. The resulting lower oxygen affinity leads to a decreased stimulation of erythropoiesis and hence to its regulation at lower hemoglobin levels. Accordingly we suggest that the beta-thalassemia trait is a pseudo-anemia, because it is unlikely that these heterozygotes are unable to reach normal hemoglobin values by increasing erythrocyte output.
 ...
PMID:[Anemia 2,3-DPG and tissue oxygenation in beta-thalassemia heterozygotes]. 716 85

The growth of syngeneic hemangiopericytoma in CBA X X C57BL/6j)F1 male mice was attended by the development of leukemoid reaction. The spleen showed an abrupt increase of the area taken by the red pulp with a remarkable activation of erythropoiesis in the pulp. The peripheral blood developed erythrocytosis 7 days after transplantation of pericytoma followed by anemia.
 ...
PMID:[Response of lymphoid and hematopoietic tissues to the growth of syngeneic transplantable hemangiopericytomas in mice]. 729 50

A thiamine (T) deficient state in rats was produced by feeding the rats a T deficient diet (TDD). At the stage of 13 days (TDD13 group), the number of red blood cells (RBC) and white blood cells (WBC), hematocrit (Ht) and hemoglobin (Hb) values decreased. On the other hand, after 30 days on the TDD (TDD30 group), the number of RBC was 819 x 10(4)/mm3 as against 631 x 10(4)/mm3 in the normal control group (NC group). Ht and Hb values also increased in the TDD30 group. These changes observed in the TDD30 group were significantly different from findings in the equal weight control group (EWC group) or in the pair fed control group (PFC group). The number of reticulocytes increased, the levels of 2,3-diphosphoglycerate (2,3-DPG) of RBC decreased and plasma erythropoietin levels increased in the TDD30 group. T levels of blood in the TDD13 group were 62 (39-79) ng/ml as against 275 (196-412) ng/ml in the NC group. T levels of blood in the TDD30 group were 102 (17-365) ng/ml, and widely varied. Decrease in 2,3-DPG produces an increase in O2 affinity to Hb, and hypoxia is induced in the peripheral tissues. Furthermore these conditions stimulate erythropoietin production and finally the number of RBC increases. T deficiency produces anemia at an early stage and absolute erythrocytosis occurs at the late stage of T deficiency. The increased osmotic resistance of RBC in hypotonic solution was also observed in the TDD30 group. This increase in osmotic resistance correlated with the decrease in cholesterol and phospholipid levels in the membrane of RBC.
 ...
PMID:Erythrocytosis in thiamine deficient rats. 733 40

A young American woman of Thai ancestry living in Ohio and a man of Vietnamese origin living in Iowa are believed to be the first recognized hemoglobin E homozygotes residing in the western hemisphere. Both were clinically well and exhibited neither pallor nor icterus nor splenomegaly. Their blood exhibited marked microcytosis and mild erythrocytosis. Hemoglobin was 99% E and 1% F, 97% E and 3% F, respectively. These features were similar to those previously reported from Southeast Asia and Madagascar in the few well-documented reports of homozygous hemoglobin E. A 51Cr erythrocyte survival study indicated a normal t1/2 of 28 days. Also demonstrated were minimal decrease in whole blood O2 affinity and increased ratio of alpha/non-alpha globin chain synthesis. Mild hemolytic anemia is not, as usually stated, a feature of this condition, which closely mimics a very mild thalassemia minor. Anemia, when found with high proportions of hemoglobin E, should not be attributed to the homozygous hemoglobinopathy. Persons with homozygous hemoglobin E should be reassured as to its benign implications.
 ...
PMID:Homozygous hemoglobin E mimics beta-thalassemia minor without anemia or hemolysis: hematologic, functional, and biosynthetic studies of first North American cases. 739 58


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>