What is decreased in all types of anemia as indicated by CBC blood work?

In all types of anemia, hemoglobin levels are decreased, which is a hallmark characteristic identifiable through a Complete Blood Count (CBC). Hemoglobin is the oxygen-carrying protein in red blood cells, and its reduction reflects a deficiency in the capacity of blood to transport oxygen throughout the body.

Anemia can result from various factors, including inadequate production of red blood cells, increased destruction of red blood cells, or blood loss. Regardless of the underlying cause, the common feature across different types of anemia is the lowered level of hemoglobin, which ultimately leads to symptoms like fatigue, weakness, and pallor due to decreased oxygenation of tissues.

While the red blood cell count is often reduced in anemia, it is not universally decreased in all forms, especially during early stages or in certain cases like hemolytic anemia where the count may be relatively normal or even increased initially. White blood cell and platelet counts are not directly affected by anemia and may remain within normal ranges unless there are additional concurrent conditions impacting these cell lines. Thus, the decrease in hemoglobin levels serves as a definitive indicator of anemia in various contexts.