What condition is characterized by a deficiency of red blood cells or hemoglobin?

The condition characterized by a deficiency of red blood cells or hemoglobin is anemia. Anemia results in a reduced capacity of the blood to carry oxygen to tissues, which can lead to symptoms such as fatigue, weakness, and pallor. It can arise from various underlying causes, including nutritional deficiencies (like iron or vitamin B12), chronic diseases, or bone marrow disorders.

This understanding of anemia highlights its defining feature: a shortage of red blood cells or hemoglobin, setting it apart from conditions like leukopenia, which pertains to a decrease in white blood cells, hyperlipidemia, associated with elevated levels of lipids in the blood, and polycythemia, characterized by an increase in red blood cells. These differentiations are critical in identifying and diagnosing hematological issues.