Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Influences of hemoglobin (Hb) variants (HbSS, HbCC, beta-thalassemia, HbAE, HbAS, HbAC, hereditary persistent HbF) and Hb derivatives (carbamylated- and acetylated-Hbs, Schiff base, and those formed in stored blood) on results of glyco-Hb assays by 102 laboratories using 16 different methods were investigated. Affinity chromatography shows deviating results only with homozygous Hb S and C. Correct interpretation of results from patients with decreased erythrocyte half-lives requires previous knowledge on this condition. Measurements of HbA1c by HPLC and electrophoresis are obviously unsuitable for homozygous hemoglobinopathies; for heterozygous hemoglobinopathies and Hb synthesis variants, HbA1c should be expressed as percentage of HbA0 + HbA1c; abnormal Hbs are usually recognized; both carbamylated- and acetylated-Hbs interfere and Schiff base must be eliminated. Except for stored blood, all Hb variants and derivatives gave erroneous results with disposable ion-exchange columns. Dako's immunoassay is not affected by Hb derivatives; glycated Hb variants are not recognized as glyco-Hb and percentages are consequently too low. Glyco-Hb by the immunoassay of Bayer (performed by one laboratory) is not affected by Hb variants and derivatives.
 ...
PMID:Influence of hemoglobin variants and derivatives on glycohemoglobin determinations, as investigated by 102 laboratories using 16 methods. 768 46

Using the new Bayer H*3 hematology analyzer (Leverkusen, Germany), we have determined red blood cell and reticulocyte indices in 64 healthy subjects, in patients with microcytosis due to iron deficiency (58 patients) and heterozygous beta-thalassemia (40 patients), and in patients with macrocytosis (28 patients). We found in all cases that reticulocytes were larger than mature red cells by 24% to 35%, with a hemoglobin concentration 16% to 25% lower and a similar hemoglobin content. The correlation between red cell and reticulocyte indices was strikingly tight (r = .928 for volume, r = .929 for hemoglobin concentration, r = .972 for hemoglobin content) in all four groups, regardless of red blood cell size. The ratio of reticulocyte to red blood cell mean corpuscolar volume (MCV ratio) was constantly above 1. Inversion of the MCV ratio was observed only in four patients. It was always abrupt and transitory and was associated with erythropoietic changes leading to the production of red blood cells of a different volume (treatment of megaloblastic anemia, functional iron deficiency, bone marrow transplantation). In two cases of marrow transplantation, reticulocyte volume fell during the aplastic phase after conditioning chemotherapy and then rapidly increased up to values higher than before; this production of macroreticulocytes was the earliest sign of engraftment.
 ...
PMID:Simultaneous measurement of reticulocyte and red blood cell indices in healthy subjects and patients with microcytic and macrocytic anemia. 783 82