What is the most probable cause of decreased hemoglobin, hematocrit, and other indicative results from a CBC?

The most probable cause of decreased hemoglobin, hematocrit, and other indicative results from a complete blood count (CBC) is anemia. Anemia is characterized by a deficiency in red blood cells or hemoglobin, leading to a reduced capacity of the blood to carry oxygen. This reduction in red blood cell mass typically manifests as lowered values in both hemoglobin and hematocrit levels.

In clinical practice, various forms of anemia can lead to these typical findings, such as iron deficiency anemia, vitamin B12 deficiency, or anemia of chronic disease, among others. These conditions cause the body to produce fewer red blood cells or lead to their premature destruction, ultimately resulting in anemia.

In contrast, conditions like polycythemia involve an increase in red blood cell mass, leukemia primarily affects white blood cell production and can complicate red blood cell functionality or quantity, and thrombocytopenia specifically refers to low platelet counts, neither of which would explain the decreased hemoglobin and hematocrit levels associated with anemia.