Anemia
, Anemia anemia (also spelled anaemia) is a decrease
in the total amount of red blood cells (RBCs) or
hemoglobin in the blood, or a lowered ability of the blood
to carry oxygen. When anemia comes on slowly, the
symptoms are often vague and may include feeling tired,
weakness, shortness of breath, and a poor ability to
exercise. When the anemia comes on quickly, symptoms
may include confusion, lightheadedness, loss of
consciousness, and increased thirst Anemia must be
significant before a person becomes noticeably pale.
Additional symptoms may occur depending on the
underlying cause. For people who require surgery, pre-
operative anemia can increase the risk of requiring a
blood transfusion following surgery
Anemia can be caused by blood loss, decreased red
blood cell production, and increased red blood cell
breakdown. Causes of blood loss include trauma and
gastrointestinal bleeding.Causes of decreased production
include iron deficiency, vitamin B12 deficiency,
thalassemia, and a number of neoplasms of the bone
marrow. Causes of increased breakdown include genetic
conditions such as sickle cell anemia, infections such as
malaria, and certain autoimmune diseases.Anemia can
also be classified based on the size of the red blood cells
and amount of hemoglobin in each cell. If the cells are
small, it is called microcytic anemia; if they are large, it is
called macrocytic anemia; and if they are normal sized, it
is called normocytic anemia. The diagnosis of anemia in
men is based on a hemoglobin of less than 130 to 140 g/L
(13 to 14 g/dL); in women, it is less than 120 to 130 g/L (12
to 13 g/dL). Further testing is then required to determine
the cause
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, Anemia anemia (also spelled anaemia) is a decrease
in the total amount of red blood cells (RBCs) or
hemoglobin in the blood, or a lowered ability of the blood
to carry oxygen. When anemia comes on slowly, the
symptoms are often vague and may include feeling tired,
weakness, shortness of breath, and a poor ability to
exercise. When the anemia comes on quickly, symptoms
may include confusion, lightheadedness, loss of
consciousness, and increased thirst Anemia must be
significant before a person becomes noticeably pale.
Additional symptoms may occur depending on the
underlying cause. For people who require surgery, pre-
operative anemia can increase the risk of requiring a
blood transfusion following surgery
Anemia can be caused by blood loss, decreased red
blood cell production, and increased red blood cell
breakdown. Causes of blood loss include trauma and
gastrointestinal bleeding.Causes of decreased production
include iron deficiency, vitamin B12 deficiency,
thalassemia, and a number of neoplasms of the bone
marrow. Causes of increased breakdown include genetic
conditions such as sickle cell anemia, infections such as
malaria, and certain autoimmune diseases.Anemia can
also be classified based on the size of the red blood cells
and amount of hemoglobin in each cell. If the cells are
small, it is called microcytic anemia; if they are large, it is
called macrocytic anemia; and if they are normal sized, it
is called normocytic anemia. The diagnosis of anemia in
men is based on a hemoglobin of less than 130 to 140 g/L
(13 to 14 g/dL); in women, it is less than 120 to 130 g/L (12
to 13 g/dL). Further testing is then required to determine
the cause
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