Fetal hemoglobin anemia

Feature presentations of SCD are hemolytic anemia and vasoocclusion. Symptoms are delayed until 4 to 6 months of age when HbS replaces fetal hemoglobin (HbF). Common findings include pain with fever, pneumonia, splenomegaly and, in infants, pain and swelling of the hands and feet (e.g., hand-and-foot syndrome or dactylitis). 

M. A., Moore, J. W., Hydroxyurea-induced augmentation of fetal hemoglobin production in patients with sickle cell anemia, Blood 69 (1987), p. 109-116... 

Dover GJ, Brusilow S, Charache S (1994) Induction of fetal hemoglobin production in subjects with sickle cell anemia by oral sodium phenylbutyrate. Blood 84 339-343 El Kharroubi A, Martin MA (1996) cis-acting sequences located downstream of the human immunodeficiency virus type 1 promoter affect its chromatin structure and transcriptional activity. Mol Cell Biol 16 2958-2966... 

Individuals with sickle cell anemia have a functional gene for the gamma chain. If the production of fetal hemoglobin could be turned back on the affected individuals could function normally except during pregnancy. 

H59. Huisman, T. H. J., Schroeder, W. A., Bouver, N., Miller, A., Shelton, J. R., Shelton, J. B., and Apell, G., Chemical heterogeneity of fetal hemoglobin in subjects with sickle cell anemia, homozygous Hb-C disease, SC-disease, and various combination of hemoglobin variants. Clin. Chim. Acta 38, 5-16 (1972). 

Resar LMS, Segal JB, Fitzpatric LK, et al. Induction of fetal hemoglobin synthesis in children with sickle cell anemia on low-dose oral sodium phenylbutyrate therapy. J Pediatr Hematol Oncol 2002 24 737— 741. 

Two observations have led to a possible treatment of these diseases. First, physicians found some sickle cell anemia patients who suffered only mild symptoms because they continued to make high levels of fetal hemoglobin. Second was the observation that some babies born to diabetic mothers contin-... 

In addition. Will Sichel was treated with hydroxyurea therapy, which increases the production of red blood cells containing fetal hemoglobin. ITbF molecules cannot participate in sickling. Will Sichel s acute symptoms gradually subsided. Had his severe pain persisted, partial exchange blood transfnsions would have been considered because no other effective therapy is cnrrently available. Patients with sickle cell anemia periodically experience sickle cell crises, and Will s physician nrged him to seek medical help whenever symptoms reappeared. 

Itano, H. A.. The identification of fetal hemoglobin ill sickle-cell anemia by electrophoretic, spectrophoto-metric, and solubility studies unpublished investigation. 

Fig. 6. A chart representing possible combinations of the alleles A, S, C, D, and E. The horizontal row at the bottom represents simultaneous occurrence with thalassemia minor. The amount of fetal hemoglobin usually present is also indicated F means a few per cent, F means 10 per cent or more. Observed conditions are shown within heavy borders. At the top the seriousness of different kinds of anemia is indicated.

The seriousness of these diseases (not including AC -f- Th and E + Th, for which the number of patients is too small to permit an estimate) is indicated at the top of Fig. 6. There is some variability in the seriousness of the diseases, in part as the result of the extent to which compensation of abnormal hemoglobins is achieved through the manufacture of fetal hemoglobin. The mildest anemias are SC and CC. Not all SC and CC individuals are anemic. Although they probably have a greater than normal rate of hemolysis, they may be able to compensate completely with a greater than normal rate of production of red blood cells. ... 

The spleen may also become enlarged when the marrow Is unable to further undertake hema-lopolesls. The primitive production of fetal hemoglobin can be reestablished and may help maintain the blood s oxygen-carrying capacity in spite of idiopathic anemia. The liver may increase in size from infection or other toxic influence. Hepatitis, or Inflammation of the liver, frequently results In hepatomegaly. Subsequent to Infection, It may be quite some time before the lymphatic tissue regresses to its previous size, if at all. 

The answer is 3 [It C/. Plasma iron and erythropoietin levels are increased in aplastic anemia because the reduced bone marrow mass is unable to fully use these components in normal synthesis. Aplastic anemia usually is a result of r uced deoxyribonucleic acid (DNA)-controlled synthesis of pluripolent bone marrow precursors of erythrocytes, leukocytes, and thrombcxtytes. Fetal hemoglobin synthesis may increase in adults with aplastic anemia. Aplastic anemia is characterized by macrocytes and increased numbers of reticulocytes. 

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