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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In evaluating pregnant women with anemia, it is essential to do a complete history and physical examination, as well as a complete blood count with indices and a blood smear examination. Based on these findings, other tests such as ferritin and serum or red cell folate may be ordered. Because of the normal physiologic changes in pregnancy that affect the hematocrit, indices, and some other parameters, diagnosing true anemia, as well as the etiology of anemia, is challenging. Because of the increased nutritional requirements of the mother and fetus, the most common anemias are iron deficiency anemia and folate deficiency megaloblastic anemia. These anemias are more common in women who have inadequate diets and who are not receiving prenatal iron and folate supplements. Other less common causes of acquired anemia in pregnancy are aplastic anemia and hemolytic anemia associated with preeclampsia. In addition, congenital anemias such as sickle cell disease can impact on the health of the mother and fetus. Obviously, severe anemia has adverse effects on the mother and the fetus. There is also evidence that less severe anemia is associated with poor pregnancy outcome. The cause of this association has yet to be elucidated. It is important, however, to diagnose and treat anemia in pregnancy to provide for optimal health of the mother and infant.
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PMID:Anemia in pregnancy. 157 61

Persons with sickle cell anemia have several indications for transfusion of red blood cells. One of the complications of transfusion of red blood cells is iron overload. Iron overload has been associated with multiple endocrine abnormalities. We report herein three cases of hypothyroidism in adult individuals with sickle cell disease. All three patients were over the age of 45 years at the time of the diagnosis and had received multiple units of transfused red blood cells and had serum ferritin levels of greater than 6,000 ng/mL. All patients were diagnosed during times when they were critically ill. Replacement therapy was instituted in all cases; however, all three patients died shortly after the diagnosis of hypothyroidism was made. Congestive heart failure appeared to be a primary cause of death in all three patients. In the one patient in whom a postmortem examination was done, there was evident extensive fibrosis of the thyroid gland as well as extensive deposition of iron in the cells lining the thyroid follicles. We believe that this represents the first report of clinical hypothyroidism in patients with sickle cell anemia who have received multiple transfusions. Awareness of this condition is especially important given that congestive heart failure is common in sickle cell disease.
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PMID:Hypothyroidism in adults with sickle cell anemia. 158 Mar 5

Hydroxyurea is well absorbed after oral administration, converted to a free radical nitroxide in vivo, and transported by diffusion into cells where it quenches the tyrosyl free radical at the active site of the M2 protein subunit of ribonucleotide reductase, inactivating the enzyme. The entire replitase complex, including ribonucleotide reductase, is inactivated and DNA synthesis is selectively inhibited, producing cell death in S phase and synchronization of the fraction of cells that survive. Repair of DNA damaged by chemicals or irradiation is also inhibited by hydroxyurea, offering potential synergy between hydroxyurea and radiation or alkylating agents. Hydroxyurea renders cells sensitive to bleomycin because the quenched tyrosyl free radical no longer stabilizes the adjacent iron center, making it more susceptible to the chelating properties of bleomycin, which then produces active oxygen. Synergy has also been observed between hydroxyurea and a number of other chemotherapeutic agents, including cytarabine and etoposide. Recently, two new effects of hydroxyurea have been observed: hydroxyurea increases the level of fetal hemoglobin, leading to a reduction in the incidence of vasoocclusive crises in sickle cell anemia, and hydroxyurea selectively reduces the level of episomal DNA and thus potentially may reduce drug resistance associated with duplicated genes retained as episomes. Further exploration of the efficacy of hydroxyurea in combination with other therapeutic agents is warranted.
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PMID:Mechanism of action of hydroxyurea. 164 48

We describe a rare set of monozygotic twins with coexistent sickle cell anemia and alpha-/alpha alpha thalassemia who have asynchronous painful crises of different frequency and severity. Studies include measurements of cell deformability and other hemorheologic tests, cell density distribution, the percentage of irreversibly sickled cells, adherence of red cells to endothelial cells, membrane heme and membrane free iron, calcium containing internal vesicles and serum antioxidants. Results of these studies, including estimates of organ damage (bone, spleen, retina), were similar except for an increase in red cell membrane free iron in the patient with more frequent and severe painful crises. The study supports the concept that non-inherited factors are important contributors to the frequency and severity of painful crises in sickle cell anemia.
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PMID:Monozygotic twins with sickle cell anemia and discordant clinical courses: clinical and laboratory studies. 172 71

A 50 year-old patient with sickle cell anemia was seen who had received only two units of blood during his lifetime. He had marked iron overloading, cirrhosis of the liver, arthralgia, and mild glucose intolerance. We believe the iron overloading was associated with hereditary hemochromatosis rather than sickle cell anemia because he had HLA-A3 and B7 antigens, and hepatic iron deposits were primarily in parenchymal cells rather than Kupfer cells. The coexistence of either homozygous or heterozygous hemochromatosis should be suspected in sickle cell patients with organ damage from iron overloading.
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PMID:Sickle cell disease and hemochromatosis. 195 9

Advances in the treatment of iron overload hold the promise of making long-term transfusion therapy a safer approach to the management of thalassemia major, sickle cell disease, and numerous other hematologic disorders. The responsibility now placed on the treating physician is to monitor iron stores carefully, to begin chelation therapy at an appropriate time, and to encourage regular use of deferoxamine. For the clinical investigator, the success of chelation therapy with deferoxamine should prompt an intensive search for new chelators. These new chelators should be not only effective but also inexpensive, readily available, safe, and easy to administer.
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PMID:Treatment of transfusional iron overload. 217 59

Disorders of hemoglobin synthesis affect the musculoskeletal system by either causing replacement of bone by hematopoietic tissue, precipitating bone and soft tissue ischemia and necrosis, or a combination of both processes. Less frequently, joints are involved by synovial ischemia, synovial deposition of iron, or microfracture of subchondral bone. Osteopenia is a significant problem in both thalassemia and sickle cell anemia and may result in vertebral and long bone fractures. Growth disturbances are frequently seen but are not often appreciated until adolescence because of improved hematologic management. The cause of the growth problems is multifactorial and may be related to hormonal deficiencies, iron overload, hypoxia, or local trauma to the growth plate secondary to significant osteopenia.
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PMID:Musculoskeletal problems in hemoglobinopathy. 229 57

A case of sickle cell disease diagnosed postmortem is described. A 37-year-old black woman presented with anemia, respiratory distress, and abdominal and back pain. Death followed an intramuscular injection of iron, and anaphylaxis was clinically diagnosed. At autopsy, massive fat and necrotic bone marrow embolization of pulmonary and renal vessels was found. In the vertebral column, multifocal areas of ischemic necrosis were present, and proved to be the source of this embolization. Sickled red cells appeared in bone marrow sinusoids, and signs of disseminated intravascular coagulation were present.
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PMID:Massive fat and necrotic bone marrow embolization in a previously undiagnosed patient with sickle cell disease. 230 55

37Fe Moessbauer spectroscopy has been applied to the study of iron deposits in patients with altered iron metabolism. Haematological parameters were also studied in order to analyse their relationship with Moessbauer results. Within the aim of this research, 12 samples of packed red blood cells were analysed: 6 with beta-thalassaemia major, 2 with S-beta-thalassaemia, 1 with sickle cell anaemia and 3 from normal subjects used as control for Moessbauer spectroscopy. Moessbauer spectra of 6 red blood cells samples showed that besides the two components, i.e., oxy and deoxy haemoglobin present in samples of normal subjects, appears a third component with Moessbauer parameters corresponding to ferritin-like iron. Correlation of % transferrin saturation (TS %) with ferritin-like iron (r = 0.90, p less than 0.05) as well as between TS % and the ratio ferritin-like iron/Hb iron (r = 0.91, p less than 0.05) was found. A tendency to correlation of serum ferritin (SF) with ferritin-like iron (r = 0.90, p less than 0.05) as well as between TS % and the ratio ferritin-like iron/Hb iron (r = 0.91, p less than 0.05) was found. A tendency to correlation of SF with ferritin-like iron (r = 0.78) and with the ratio ferritin-like iron/Hb iron, was also observed. It can be concluded that Moessbauer spectroscopy could be a useful technique in the study of this kind of pathology.
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PMID:[Application of Mossbauer spectroscopy to the study of hemoglobinopathies. Preliminary experience]. 261 81

Iron chelation therapy must be associated with the regular blood transfusions required for thalassaemia and other chronic anemias. We report here a study concerning 4 groups of patients, aged 6 to 28, regularly transfused at Necker Enfants-Malades hospital: a) 20 with thalassaemia major; b) 6 with thalassaemia intermedia; c) 2 with sickle cell disease and d) 2 with Blackfan-Diamond syndrome. The transfusion regimen consisting of monthly or quarterly transfusions varied as a function of the groups. Desferal was used in all patients. The dosage and the route of administration (IV, IM, SC) were adapted to the amount of iron transfused and to the nature of the disease. The serum ferritin level was considered as the indicator of the iron overload. Comparisons were established between the quantities of iron transfused, ferritin levels, and parameters such as dosage, route of administration and compliance to Desferal. During the period of study 3 patients died from cardiac failure due to transfusional hemosiderosis. Endocrine complications (diabetes 2 cases, hypocalcemia 3 cases, hypothyroidism 1 case and delayed puberty 7 cases) were observed. This high incidence of complications induced by post-transfusional iron overload has recently prompted us to improve the quality of chelation therapy through the use of the services of a specialized center where patients as well as their families can be trained more adequately in home care and self-treatment.
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PMID:[Treatment of post-transfusion iron overload by deferoxamine]. 273 4


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