Term
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Definition
| A family of congenital disorders in which mutations in one or more of the globin genes of hemoglobin cause decreased or absent synthesis of the corresponding globin chains |
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Term
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Definition
| are quantitative disorders which decrease the amount hemoglobins, deletions or non-deletions cause the globin chain to be produced in decreased amounts which causes inadequate amounts of normal hemoglobin |
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Term
| Pathology of hemoglobinothaies |
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Definition
| Hemoglobinopathies results in qualitative defects in hemoglobin production which affect the hemoglobin function, caused by point mutations which result in abnormal hemoglobin |
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Term
| Typical peripheral blood morphology associated with thalassemia |
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Definition
| Microcytic hypochromic (decrease in hemoglobin concentration) peripheral blood smear |
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Term
| etiology of α- thalassemia |
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Definition
| impaired α-chain synthesis and increased levels of β chain |
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Term
| etiology of and β- thalassemia |
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Definition
| impaired β-chain synthesis and increased levels of α chain |
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Term
| Number of affected alleles: Hydrops Fetalis |
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Definition
| all four α alleles are affected and deleted |
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Term
| Individuals affected: Hydrops Fetalis |
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Definition
| affects individuals of Mediterranean, Asian, and African ancestry |
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Term
| Basic pathophysiology: Hydrops Fetalis |
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Definition
| the inability to produce α chain is incompatible with life, adult hemoglobin (HbA) is necessary for life |
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Term
| Symptoms: Hydrops Fetalis |
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Definition
| Abnormal tetramers have a high affinity for oxygen and infants die from hypoxia or congestive heart failure at birth |
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Term
| blood cell morphology: Hydrops Fetalis |
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Definition
| shows severe anemia with low hemoglobin (3.0-10.0 g/dL), hemoglobin |
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Term
| hemoglobin electrophoresis: Hydrops Fetlis |
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Definition
| electrophoresis shows 80-90% Hb Bart’s (γ4), 10-20% Hb Portland (ζ2γ2), HbH (β4) could be present, and HbA, HbA2 and HbF are ABSENT because they all require α chains |
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Term
| Number of affected alleles: Hb H disease |
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Definition
| 3 of 4 α genes are affected |
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Term
| Individuals affected: Hb H disease |
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Definition
| affects individuals of Mediterranean, Asian, and African ancestry |
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Term
| Basic pathophysiology: HbH disease |
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Definition
| decreased production of HbA, HbA2 and HbF, excess of β chains unite to form HbH which is unstable and precipitates in RBCs and has increased oxygen affinity reduces oxygen delivery to the tissues |
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Term
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Definition
| anemia, chronic hemolysis, splenomegaly, hepatomegaly, less than ½ exhibit skeletal changes (due to unusual bones producing RBCs) |
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Term
| blood cell morphology: HbH disease |
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Definition
| microcytic hypochromic anemia, low hemoglobin (8-10 g/dL), increased reticulocyte (5-10%), and nucleated RBCs, |
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Term
| hemoglobin electrophoresis: Hb H disease |
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Definition
| in neonates shows 25% Hb Bart’s, and decreased levels of HbA, HbA2, and HbF, Hb electrophoresis in adults shows 2-40% HbH, decreased HbA2 levels, and normal HbF levels, the remaining hemoglobin is HbA |
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Term
| Number of affected alleles: alpha-thalassemia minor |
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Definition
| half of the α genes are affected |
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Term
| individuals affected: alpha-thalassemia minor |
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Definition
| the individuals affected are of Mediterranean, Asian, and African ancestry |
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Term
| Basic pathophysiology: alpha-thalassemia minor |
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Definition
| unaffected globin genes are able to direct synthesis of α globin chains to a greater than normal degree and therefore compensate for the affected genes |
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Term
| symptoms: alpha-thalassemia minor |
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Definition
| asymptomatic with a mild anemia |
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Term
| blood cell morphology: alpha-thalassemia minor |
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Definition
| blood cell morphology shows hemoglobin counts above 10.0 g/dL and RBC count above 5 x 1012/L, peripheral blood shows microcytosis with an MCV of 60-70fl with a few target cells, some cells can exhibit HbH inclusions, |
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Term
| hemoglobin electrophoresis: alpha-thalassemia minor |
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Definition
| in infants shows Hb Bart’s 5-6% |
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Term
| Number of affected alleles: silent carrier |
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Definition
| one of the α genes are affected |
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Term
| individuals affected: silent carrier |
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Definition
| in individuals affected are African Americans (25%) |
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Term
| Basic pathophysiology: silent carrier |
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Definition
| three remaining α genes direct the synthesis of an adequate number of α chains for normal hemoglobin synthesis |
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Term
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Definition
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Term
| blood cell morphology: silent carrier |
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Definition
| blood morphology shows borderline normal MCV of 78-80fl |
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Term
| hemoglobin electrophoresis: silent carrier |
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Definition
| Hb electrophoresis of infants shows 1-2% Hb Bart’s |
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Term
| indivduals affected: Β-thalassemia major |
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Definition
| people of Mediterranean regions (northern Italy, Greece, Algeria, Saudi Arabia) and southeast Asia |
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Term
| Basic pathophysiology: Β-thalassemia major |
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Definition
| decreased production of HbA, increased production of HbA2 and HbF, excess free α chains precipitate damage the RBC membrane and creative reactive O2 species which affect other proteins |
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Term
| Symptoms: Β-thalassemia major |
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Definition
| in infants we see irritability, pallor, failure to thrive, diarrhea, fever, and enlarged abdomen, in adults we see severe anemia, cardiac failure, bronze pigmentation of skin, bone changes (hairy bones) and heptasplenomegaly |
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Term
| blood cell morpholoy: Β-thalassemia major |
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Definition
| shows low hemoglobin (2-3 g/dL), microcytic hypochromic, MCV < 67fl, decreased MCH and MCHC, peripheral blood smear shows Anisocytosis and Poikilocytosis, basophilic stippling, Polychromasia, nRBCs and increased RDW, α chain precipitates, leucopenia, thrombocytopenia, increased unconjugated bilirubin, dark urine, |
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Term
| hemoglobin electrophoresis: Β-thalassemia major |
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Definition
| from cord blood shows <2% HbA, in adults some or no HbA, majority of HbF, normal to variable HbA2 |
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Term
| indivduals affected: Β-thalassemia intermedia |
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Definition
| people of Mediterranean region, Middle East, Indian subcontinent, southeast Asia and a milder version in people of African descent |
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Term
| Basic pathophysiology: Β-thalassemia intermedia |
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Definition
| ineffective Erythropoiesis and extravascular hemolysis |
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Term
| Symptoms: Β-thalassemia intermedia |
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Definition
| can be mild or severe, need for transfusions is defined by the quality of life, iron overload |
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Term
| blood cell morpholoy: Β-thalassemia intermedia |
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Definition
| microcytic hypochromic anemia, low hemoglobin (7-10 g/dL), RBC count is increased, peripheral blood shows target cells, basophilic stippling, nRBCs, |
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Term
| hemoglobin electrophoresis: Β-thalassemia intermedia |
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Definition
| Hb electrophoresis of the severe forms shows majority HbF, followed by HbA2, and remainder HbA, in the milder forms HbA2 is > 3.2%, HbF 1.5-12% |
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Term
| indivduals affected: Β-thalassemia minor |
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Definition
| individuals affected are African Americans |
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Term
| Basic pathophysiology: Β-thalassemia minor |
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Definition
| normal β gene directs synthesis of sufficient amounts of β chains to synthesize enough HbA for near normal oxygen delivery and erythrocyte survival |
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Term
| Symptoms: Β-thalassemia minor |
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Definition
| asymptomatic except in period of stress (pregnancy with infections and folic acid deficiency) |
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Term
| blood cell morpholoy: Β-thalassemia minor |
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Definition
| slightly decreased hemoglobin levels (9-14 g/dL), increased RBC count, microcytic, hypochromic, |
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Term
| hemoglobin electrophoresis: Β-thalassemia minor |
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Definition
| shows an increase in HbA2, HbF is half of hemoglobin |
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Term
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Definition
| asymptomatic, exhibits no laboratory abnormalities, SC = silent carrier |
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Term
| treatment and prognosis Hydrops Fetalis |
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Definition
| blood transfusions for treatment, but quality of life is severely diminished |
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Term
| treatment and prognosis Hb H disease |
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Definition
| long-term transfusion treatments therapy (when needed), spelnectomy and folate supplementation |
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Term
| treatment and prognosis Αlpha-thalssemia minor |
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Definition
| normal life span, does not require medical intervention |
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Term
| treatment and prognosis silent carrier |
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Definition
| normal life span, does not require medical intervention |
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Term
| Explain advanced pathophysiology: Beta-thalassemia major |
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Definition
| The body reduces HbA and compensates by producing other Hbs, there is ineffective Erythropoiesis, erythroid hyperplasia, compromises blood O2 carrying capacity, excess free α chains, ineffective Erythropoiesis, BM expansion and thinning of calcified bone, extramedullary hematopoiesis |
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Term
| Describe treatment and prognosis: Beta-thalassemia major |
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Definition
| regular transfusions, iron chelating agents, spelnectomy, untreated the patient can die within 1st or 2nd decade, hypertransfusion with iron chelation can extend prognosis for > 1 decade |
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Term
| Explain advanced pathophysiology:Beta-thalassemia intermedia |
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Definition
| moderate reduction in β chain synthesis, mild or severe symptoms, α chain accumulation and precipitation is decreased reducing the ineffective Erythropoiesis and extravascular hemolysis |
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Term
| Describe treatment and prognosis: Beta-thalassemia intermedia |
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Definition
| regular infection interventions with antibiotic therapy, chelation therapy is generally warranted to combat iron overload, normal life span |
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Term
| Explain advanced pathophysiology: Beta-thalassemia minor |
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Definition
| normal β gene directs synthesis of sufficient amounts of β chains to synthesize enough HbA for near normal oxygen delivery and erythrocyte survival |
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Term
| Describe treatment and prognosis: Beta-thalassemia minor |
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Definition
| patients do not require treatment if they maintain good health and nutrition, generally asymptomatic except during period of stress, normal life expectancy |
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Term
| Explain advanced pathophysiology: Beta-thalassemia minima |
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Definition
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Term
| Describe treatment and prognosis: Beta-thalassemia minima |
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Definition
| requires no treatment and prognosis is normal life span |
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