Reticulocyte Count: The number of RETICULOCYTES per unit volume of BLOOD. The values are expressed as a percentage of the ERYTHROCYTE COUNT or in the form of an index ("corrected reticulocyte index"), which attempts to account for the number of circulating erythrocytes.Reticulocytes: Immature ERYTHROCYTES. In humans, these are ERYTHROID CELLS that have just undergone extrusion of their CELL NUCLEUS. They still contain some organelles that gradually decrease in number as the cells mature. RIBOSOMES are last to disappear. Certain staining techniques cause components of the ribosomes to precipitate into characteristic "reticulum" (not the same as the ENDOPLASMIC RETICULUM), hence the name reticulocytes.Erythrocyte Count: The number of RED BLOOD CELLS per unit volume in a sample of venous BLOOD.Blood Cell Count: The number of LEUKOCYTES and ERYTHROCYTES per unit volume in a sample of venous BLOOD. A complete blood count (CBC) also includes measurement of the HEMOGLOBIN; HEMATOCRIT; and ERYTHROCYTE INDICES.Anemia, Neonatal: The mildest form of erythroblastosis fetalis in which anemia is the chief manifestation.Erythropoiesis: The production of red blood cells (ERYTHROCYTES). In humans, erythrocytes are produced by the YOLK SAC in the first trimester; by the liver in the second trimester; by the BONE MARROW in the third trimester and after birth. In normal individuals, the erythrocyte count in the peripheral blood remains relatively constant implying a balance between the rate of erythrocyte production and rate of destruction.Erythropoietin: Glycoprotein hormone, secreted chiefly by the KIDNEY in the adult and the LIVER in the FETUS, that acts on erythroid stem cells of the BONE MARROW to stimulate proliferation and differentiation.Hematocrit: The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.Anemia, Sickle Cell: A disease characterized by chronic hemolytic anemia, episodic painful crises, and pathologic involvement of many organs. It is the clinical expression of homozygosity for hemoglobin S.Anemia, Hemolytic, Autoimmune: Acquired hemolytic anemia due to the presence of AUTOANTIBODIES which agglutinate or lyse the patient's own RED BLOOD CELLS.Heinz Bodies: Abnormal intracellular inclusions, composed of denatured hemoglobin, found on the membrane of red blood cells. They are seen in thalassemias, enzymopathies, hemoglobinopathies, and after splenectomy.Erythrocyte Aging: The senescence of RED BLOOD CELLS. Lacking the organelles that make protein synthesis possible, the mature erythrocyte is incapable of self-repair, reproduction, and carrying out certain functions performed by other cells. This limits the average life span of an erythrocyte to 120 days.Hemoglobins: The oxygen-carrying proteins of ERYTHROCYTES. They are found in all vertebrates and some invertebrates. The number of globin subunits in the hemoglobin quaternary structure differs between species. Structures range from monomeric to a variety of multimeric arrangements.Anemia, Hemolytic: A condition of inadequate circulating red blood cells (ANEMIA) or insufficient HEMOGLOBIN due to premature destruction of red blood cells (ERYTHROCYTES).Anemia: A reduction in the number of circulating ERYTHROCYTES or in the quantity of HEMOGLOBIN.Hematologic Tests: Tests used in the analysis of the hemic system.Phenylhydrazines: Diazo derivatives of aniline, used as a reagent for sugars, ketones, and aldehydes. (Dorland, 28th ed)Coombs Test: A test to detect non-agglutinating ANTIBODIES against ERYTHROCYTES by use of anti-antibodies (the Coombs' reagent.) The direct test is applied to freshly drawn blood to detect antibody bound to circulating red cells. The indirect test is applied to serum to detect the presence of antibodies that can bind to red blood cells.Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Bloodletting: Puncture of a vein to draw blood for therapeutic purposes. Bloodletting therapy has been used in Talmudic and Indian medicine since the medieval time, and was still practiced widely in the 18th and 19th centuries. Its modern counterpart is PHLEBOTOMY.Erythrocyte Indices: ERYTHROCYTE size and HEMOGLOBIN content or concentration, usually derived from ERYTHROCYTE COUNT; BLOOD hemoglobin concentration; and HEMATOCRIT. The indices include the mean corpuscular volume (MCV), the mean corpuscular hemoglobin (MCH), and the mean corpuscular hemoglobin concentration (MCHC).Hemolysis: The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.Anemia, Macrocytic: Anemia characterized by larger than normal erythrocytes, increased mean corpuscular volume (MCV) and increased mean corpuscular hemoglobin (MCH).Fetal Hemoglobin: The major component of hemoglobin in the fetus. This HEMOGLOBIN has two alpha and two gamma polypeptide subunits in comparison to normal adult hemoglobin, which has two alpha and two beta polypeptide subunits. Fetal hemoglobin concentrations can be elevated (usually above 0.5%) in children and adults affected by LEUKEMIA and several types of ANEMIA.Iron: A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.Red-Cell Aplasia, Pure: Suppression of erythropoiesis with little or no abnormality of leukocyte or platelet production.Erythrocyte Transfusion: The transfer of erythrocytes from a donor to a recipient or reinfusion to the donor.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Ferritins: Iron-containing proteins that are widely distributed in animals, plants, and microorganisms. Their major function is to store IRON in a nontoxic bioavailable form. Each ferritin molecule consists of ferric iron in a hollow protein shell (APOFERRITINS) made of 24 subunits of various sequences depending on the species and tissue types.Anemia, Aplastic: A form of anemia in which the bone marrow fails to produce adequate numbers of peripheral blood elements.Blood Transfusion: The introduction of whole blood or blood component directly into the blood stream. (Dorland, 27th ed)Bone Marrow: The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.Protein Biosynthesis: The biosynthesis of PEPTIDES and PROTEINS on RIBOSOMES, directed by MESSENGER RNA, via TRANSFER RNA that is charged with standard proteinogenic AMINO ACIDS.Leukocyte Count: The number of WHITE BLOOD CELLS per unit volume in venous BLOOD. A differential leukocyte count measures the relative numbers of the different types of white cells.Cell-Free System: A fractionated cell extract that maintains a biological function. A subcellular fraction isolated by ultracentrifugation or other separation techniques must first be isolated so that a process can be studied free from all of the complex side reactions that occur in a cell. The cell-free system is therefore widely used in cell biology. (From Alberts et al., Molecular Biology of the Cell, 2d ed, p166)Hematopoiesis: The development and formation of various types of BLOOD CELLS. Hematopoiesis can take place in the BONE MARROW (medullary) or outside the bone marrow (HEMATOPOIESIS, EXTRAMEDULLARY).Injections, Subcutaneous: Forceful administration under the skin of liquid medication, nutrient, or other fluid through a hollow needle piercing the skin.Platelet Count: The number of PLATELETS per unit volume in a sample of venous BLOOD.Peptide Initiation Factors: Protein factors uniquely required during the initiation phase of protein synthesis in GENETIC TRANSLATION.CD4 Lymphocyte Count: The number of CD4-POSITIVE T-LYMPHOCYTES per unit volume of BLOOD. Determination requires the use of a fluorescence-activated flow cytometer.Infant, Newborn: An infant during the first month after birth.Spleen: An encapsulated lymphatic organ through which venous blood filters.Globins: A superfamily of proteins containing the globin fold which is composed of 6-8 alpha helices arranged in a characterstic HEME enclosing structure.Hemin: Chloro(7,12-diethenyl-3,8,13,17-tetramethyl-21H,23H-porphine-2,18-dipropanoato(4-)-N(21),N(22),N(23),N(24)) ferrate(2-) dihydrogen.Peptide Chain Initiation, Translational: A process of GENETIC TRANSLATION whereby the formation of a peptide chain is started. It includes assembly of the RIBOSOME components, the MESSENGER RNA coding for the polypeptide to be made, INITIATOR TRNA, and PEPTIDE INITIATION FACTORS; and placement of the first amino acid in the peptide chain. The details and components of this process are unique for prokaryotic protein biosynthesis and eukaryotic protein biosynthesis.Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)MedlinePlus: NATIONAL LIBRARY OF MEDICINE service for health professionals and consumers. It links extensive information from the National Institutes of Health and other reviewed sources of information on specific diseases and conditions.EncyclopediasAdenosine Deaminase: An enzyme that catalyzes the hydrolysis of ADENOSINE to INOSINE with the elimination of AMMONIA.Adenosine Deaminase Inhibitors: Drugs that inhibit ADENOSINE DEAMINASE activity.Sickle Cell Trait: The condition of being heterozygous for hemoglobin S.Adenosine: A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.
  • Acquired pure red cell aplasia is a rare disorder, usually appearing secondary to various pathologic conditions such as thymoma, systemic autoimmune diseases or in the course of lymphomas. (biomedcentral.com)
  • 8 weekly courses of rituximab were administered to a patient who presented with pure red cell aplasia secondary to newly diagnosed splenic marginal zone lymphoma. (biomedcentral.com)
  • Transfusion independence was achieved after the 6th course, and pure red cell aplasia receded completely with therapy. (biomedcentral.com)
  • Pure red cell aplasia may ensue early in the course of splenic marginal zone lymphoma and other low grade lymphomas. (biomedcentral.com)
  • Rituximab is a safe and effective alternative treatment for pure red cell aplasia secondary to lymphoproliferative disorders. (biomedcentral.com)
  • This document provides guidance for the performance of reticulocyte counting by flow cytometry. (clsi.org)
  • It includes methods for determining the trueness and precision of the reticulocyte flow cytometry instrument and a recommended reference procedure. (clsi.org)
  • The relative number of SCF, Flt3, Tpo and G-CSF receptor positive, CD34 + progenitor cells were measured by flow cytometry in the leukapheresis product used for transplantation in a subgroup of 15 patients (NHL, n = 8, MM, n = 7). (nature.com)
  • Evaluations for the possible causes of PRCA should include a previous history of drug use and toxins or infections, liver and kidney functions, immunological examination including auto-antibodies, a bone marrow examination including morphology, chromosome and rearrangement of T cell receptor (TCR) analysis, peripheral-blood flow cytometry, virological examination including parvovirus B19 DNA, and computed tomography and/or magnetic resonance imaging examinations to rule out the presence of thymoma and neoplasms. (blogarama.com)
  • Shatat IF, Jakson SM, Blue AE, Johnson MA, Orak JK, Kalpatthi R. Masked hypertension is prevalent in children with sickle cell disease: a Midwest Pediatric Nephrology Consortium study. (medscape.com)
  • Children with sickle cell disease should be screened with transcranial Doppler ultrasonography starting at two years of age (frequency of rescreening has not been established). (aafp.org)
  • Infants and children with sickle cell disease should receive prophylactic daily penicillin V potassium (Veetids) starting by two months of age. (aafp.org)
  • All children with sickle cell disease are managed with the assistance of the Royal Children's Hospital Victoria. (rch.org.au)
  • High pulmonary artery pressures do occur in children with sickle cell disease. (aappublications.org)
  • There are limited data on the prevalence of PHT in children with sickle cell disease. (aappublications.org)
  • Lieberman L, Kirby M, Ozolins L, Mosko J, Friedman J. Initial presentation of unscreened children with sickle cell disease: the Toronto experience. (medscape.com)
  • Annual screening with transcranial Doppler ultrasonography is recommended for all children with sickle cell disease beginning at two years of age and continuing through adolescence to evaluate the risk of stroke and to initiate transfusion therapy in those at high risk. (aafp.org)
  • Initiate rapid treatment with opioids in adults and children with sickle cell disease and a vasoocclusive crisis with severe pain. (aafp.org)
  • DBA must be differentiated from transient erythroblastosis of childhood (TEC) , a pure red cell aplasia that usually occurs in slightly older children (6 months to 4 years) and is not associated with congenital defects. (renalandurologynews.com)
  • Pure red cell aplasia (PRCA) is an uncommon disorder in which maturation arrest occurs in the formation of erythrocytes. (blogarama.com)
  • Acquired Pure Red Cell Aplasia: This is a very rare condition and usually affects adults. (blogarama.com)
  • Pure red cell aplasia (PRCA) is a rare but well-recognized immunohematological complication that occurs in the setting of major ABO-incompatible hematopoietic stem cell transplant (HSCT). (nature.com)
  • Pure red cell aplasia" is similar disease where only production of the red blood cells is affected. (labtestsonline.org.uk)
  • Pulmonary hypertension (PHT) is a widely recognized complication of hereditary hemolytic anemias including sickle cell disease, 1 - 10 thalassemia, 11 - 13 hereditary spherocytosis, 14 and paroxysmal nocturnal hemoglobinuria. (aappublications.org)
  • Another useful indicator of anemias due to nutritional deficiencies is red cell distribution width (RDW), which increases above 15% in case of iron, folate or vitamin B 12 deficiency. (clinicaladvisor.com)
  • Obviously, infants with conotruncal defects (interrupted aortic arch, truncus arteriosus, Tetralogy of Fallot), hypocalcemia, or severe T-cell deficiency and unusual infections will be identified early. (healio.com)
  • HbS/B(+)thal: has 60% HbSS and 30% HbA, thus less severe than HbSS (sickle cell alone). (healthtap.com)
  • Anaemia can be mild, moderate or severe depending on how much the RBC count and/or haemoglobin levels have fallen. (labtestsonline.org.uk)
  • Homozygous disease (HbSS), usually called sickle cell anaemia (SCA), is the most common and severe type of disease in most populations. (bmj.com)
  • 2 Numbers are increasing, and sickle cell disease is thought to be the most common severe genetic disease in the United Kingdom and France, with 10 000-15 000 patients in each country. (bmj.com)
  • Sickle cell disease is associated with varying degrees of anaemia, red cell haemolysis, and obstruction of small blood capillaries causing painful crises, damage to major organs, and increased vulnerability to severe infections. (bmj.com)
  • The main clinical sign is profound isolated normochromic or macrocytic anaemia, with normal numbers and function of the other haemopoietic cells. (nih.gov)
  • The smear had 3+ hypochromia, 3+ microcytosis, and 2+ teardrop cells. (healio.com)
  • The treatment raised the plasma histidine concentration and at the same time there was a rise in transferrin and iron levels and packed cell volume. (bmj.com)
  • To understand what is causing your symptoms and low blood counts, your doctor will take a detailed medical history. (aamds.org)
  • It allows doctors to monitor blood counts over time and compare them with previous results. (aamds.org)