What does 'anemia' refer to in blood testing?

Anemia refers specifically to a deficiency of red blood cells or hemoglobin in the blood. Hemoglobin is the protein in red blood cells responsible for transporting oxygen throughout the body. When there is an insufficient amount of red blood cells or hemoglobin, the body's oxygen supply is compromised, leading to fatigue and various other symptoms. This condition can result from several causes, including nutritional deficiencies, chronic diseases, or genetic conditions affecting blood production.

The other options describe different blood-related conditions that are not associated with anemia. A surplus of white blood cells is indicative of conditions like infections or leukemias, while high blood pressure relates to cardiovascular health rather than blood cell counts. An increase in platelets often signifies a different type of hematological issue, such as thrombocytosis, which is distinct from the deficiencies noted in anemia. Understanding anemia's specific definition helps in recognizing its significance in patient health and clinical diagnosis.