HB

December 2016


Definition


HB is a generic term for all diseases affecting the structure of hemoglobin, a major blood protein responsible for transporting oxygen in the blood. These diseases are all caused by a hereditary abnormality of hemoglobin. There are several types of hemoglobinopathies, such as Hb S, more commonly known as sickle cell anemia, the most severe form of hemoglobinopathies. This is also congenital methemoglobinemia, or Hb M, and other hemoglobinopathies called C, E, H. .. Some are not responsible for any symptoms, while others, especially if the abnormal gene is received from both the father and the mother, cause hemolytic anemia, a decrease in the amount secondary red cell due to their destruction. Sickle cell anemia is characterized by abnormally shaped red blood cells (sickle-shaped: hence the name sickle cell anemia).

Symptoms


Symptoms of sickle cell anemia, the most severe form of Hb, are:
- chronic anemia resulting in paleness and fatigue;
- an increase in the size of the spleen, called splenomegaly;
- vaso-occlusive crises, manifested by severe pain localized mainly at the extremities, or abdominal pain secondary to obstruction by a blood thrombosis, mainly in children;
- occasional eye damage.
Numerous forms of hemoglobinopathies exist and the symptoms can vary.

Diagnosis


The diagnosis of Hb is made through laboratory tests on blood samples that will help discover hemolytic anemia with reduced red blood cell count (many red blood cells are affected), called reticulocytes. The diagnosis that characterizes the specific type of Hb is hemoglobin electrophoresis, highlighting the abnormal hemoglobin. Depending on the kind of Hb, other tests will help monitor possible complications.

Treatment


The treatment of hemoglobinopathies is specific to each type. Minor forms do not necessarily require care while those responsible for severe anemia can be treated with transfusions or by the use of folic acid supplementation. In case of vaso-occlusive crisis in person with sickle cell disease, hospitalization may be necessary with proper hydration, analgesics, possibly with bleeding transfusions. A bone marrow transplant is sometimes considered.

Prevention


In some forms of Hb, screening before birth is possible if relatives are known to be of carriers of these diseases.

Related

Original article published by . Translated by Jeff. Latest update on June 22, 2013 at 05:58 AM by Jeff.
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