II. Epidemiology: Ethnicity

  1. African descent (2% Incidence)
  2. Asian patients (Incidence common)

III. Pathophysiology

  1. See Hemoglobin Production
  2. Autosomal Recessive trait affecting two genes on each of the two Chromosome 16
  3. Results in decrease of absence of Hemoglobin Alpha chains and excess of beta chains

IV. Types

  1. Asymptomatic
    1. Alpha Thalassemia Silent Carrier
      1. Chromosome 16 gene deletions: 1 of 4
    2. Alpha Thalassemia Trait (Alpha Thalassemia Minor)
      1. Chromosome 16 gene deletions: 2 of 4
      2. Peripheral Smear shows microcytosis without Anemia
  2. Mild symptoms
    1. Hemoglobin Constant Spring
      1. Reduced alpha globin output
  3. Moderate to severe symptoms
    1. Alpha Thalassemia Intermedia
      1. Significant Hemoglobin H present (Hemoglobin composed of 4 beta chains)
      2. Chromosome 16 gene deletions: 3 of 4
    2. Alpha Thalassemia Major
      1. Significant Hemoglobin Bart's present (Hemoglobin composed of 4 gamma chains)
      2. Chromosome 16 gene deletions: 4 of 4
      3. Results in non-immune Hydrops fetalis (lethal in most cases)

V. Signs

  1. Splenomegaly
    1. Seen in Alpha Thalassemia Intermedia and higher

VI. Labs

  1. See Thalassemia
  2. Microcytosis
    1. Seen in Alpha Thalassemia trait and higher
  3. Hemolytic Anemia
    1. Seen in Alpha Thalassemia Intermedia and higher
    2. Typically more mild Anemia than seen in Beta Thalassemia

VII. Diagnosis

  1. Hemoglobin Electrophoresis

VIII. Complications

  1. Alpha Thalassemia Intermedia
    1. Mild to moderate Hemolytic Anemia
  2. Alpha Thalassemia Major
    1. Hydrops fetalis in utero (fatal)

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Ontology: alpha-Thalassemia (C0002312)

Definition (MSHCZE) Porucha alfa-řetězců. Podle počtu fungujících genů pro alfa-řetězec (normálně celkem dva páry, čili čtyři geny) existují formy s různou závažností. Nejzávažnější je mutace všech čtyř genů s výskytem hemoglobinu Bart, která je neslučitelná se životem. (cit. Velký lékařský slovník online, 2013 http://lekarske.slovniky.cz/ )
Definition (NCI) A genetic hematologic disorder characterized by partial or complete absence of the alpha globin chains of the heme molecule.
Definition (MSH) A disorder characterized by reduced synthesis of the alpha chains of hemoglobin. The severity of this condition can vary from mild anemia to death, depending on the number of genes deleted.
Concepts Disease or Syndrome (T047)
MSH D017085
ICD9 282.43
ICD10 D56.0
SnomedCT 191186002, 68913001
English alpha-Thalassemias, Disease, Hemoglobin H, Hemoglobin H Disease, Thalassemia alpha, Thalassemia-alpha, Alpha thalassaemia, Alpha-thalassemia, Alpha thalassemia, HEMOGLOBIN H DIS, Alpha-thalassaemia, Thalassaemia alpha, Hemoglobin H disease, alpha-Thalassemia [Disease/Finding], A-Thalassemia, alpha thalassaemia, alpha thalassemias, alpha-thalassemia, thalassemia alpha, alpha-thalassaemia, ALPHA-THALASSEMIA, alpha thalassemia, alpha thalassemia (diagnosis), Alpha Thalassemia, Thalassemia, Alpha, alpha Thalassemia, Alpha thalassaemia syndrome, Alpha thalassemia syndrome, alpha Thalassaemia, alpha Thalassemia (disorder), alpha; thalassemia, thalassemia; alpha, alpha Thalassemia, NOS, alpha-Thalassemia
Italian Talassemia alfa, alfa-talassemia
Dutch alfathalassemie, alfa; thalassemie, thalassemie; alfa, alfa-thalassemie, Alfa-thalassemie, Hemoglobine-H-ziekte, Thalassemie alfa, Thalassemie, alfa-
French Alphathalassémie, Alpha-thalassémie, a-Thalassémie, Hémoglobinose H, Hémoglobinopathie H, Thalassémie alpha, alpha-Thalassémie
German Alpha-Thalassaemie, Thalassaemie alpha, Alpha-Thalassämie, Hämoglobin-H-Krankheit, Thalassämie, Alpha-
Portuguese Alfa-talassemia, Talassemia alfa, Doença da Hemoglobina H
Spanish Alfa talasemia, Talasemia alfa, alfatalasemia, alfa-Talasemia, alfa Talasemia, talasemia alfa (trastorno), talasemia alfa, Enfermedad de la Hemoglobina H
Japanese αサラセミア, アルファサラセミア, アルファサラセミア, サラセミア-アルファ, アルファ地中海貧血, ヘモグロビンH症, α-サラセミア, 血色素H症
Swedish Alfatalassemi
Czech talasémie alfa, Talasemie alfa, Alfa talasemie
Finnish Alfatalassemia
Russian GEMOGLOBINOPATIIA H, AL'FA-TALASSEMIIA, TALASSEMIIA AL'FA, АЛЬФА-ТАЛАССЕМИЯ, ГЕМОГЛОБИНОПАТИЯ H, ТАЛАССЕМИЯ АЛЬФА
Korean 알파 지중해빈혈
Polish Choroba hemoglobiny H, Talasemia alfa
Hungarian Alpha-thalassaemia, Alpha thalassaemia, Thalassaemia alpha
Norwegian Alfatalassemi, Hemoglobin H-sykdom, Thalassemia-α, Talassemi-α, Alfa-talassemi