Anemia

Anemia is a condition characterized by a lower than normal level of hemoglobin in the blood or a reduced number of red blood cells, which lowers the capacity of the blood to carry oxygen to tissues. This diminished oxygen transport can affect various organs and activity levels.

The most common cause worldwide is iron deficiency, due to inadequate intake, blood loss, or poor absorption. Other causes include deficiencies of vitamin B12 or folate, chronic diseases such as kidney disease or inflammatory disorders, hemolytic or aplastic processes, and inherited conditions such as thalassemias and sickle cell disease.

Symptoms commonly include fatigue, weakness, shortness of breath, dizziness, pale skin, and fast or irregular heartbeat. Diagnosis relies on a complete blood count showing low hemoglobin and hematocrit, with red cell indices used to characterize the type of anemia. Additional tests include iron studies, B12 and folate levels, reticulocyte count, and evaluations for underlying causes such as kidney function or gastrointestinal blood loss.

Treatment targets the underlying cause. Iron deficiency is treated with oral or intravenous iron; B12 or folate deficiencies are corrected with respective supplements. Chronic diseases are managed to reduce anemia, and severe or rapidly progressive cases may require blood transfusion or, in some conditions, medications to stimulate red blood cell production. Inherited anemias may require specialized approaches, including transfusions or bone marrow transplantation.

Prognosis varies by cause and severity. Many anemias are treatable or reversible with appropriate therapy. Prevention focuses on adequate nutrition, managing chronic illnesses, screening at-risk groups, and minimizing ongoing blood loss.