What is the term for the percentage of erythrocytes in a blood sample?

The term used to describe the percentage of erythrocytes, or red blood cells, in a blood sample is hematocrit. Hematocrit is a crucial measurement in assessing various health conditions, as it indicates how much of the blood volume is made up of red blood cells, which are essential for transporting oxygen throughout the body.

In a clinical setting, measuring hematocrit can help diagnose conditions such as anemia, where there is a lower than normal level of red blood cells, or polycythemia, where there is an excessive number of red blood cells.

The other terms provided relate to different aspects of blood components. Leukocytosis refers to an increase in white blood cells, which can indicate infection or other medical conditions. Plasma volume refers to the liquid component of blood that carries cells and proteins, and hemoglobin concentration measures the amount of hemoglobin in the blood, which is vital for oxygen transport but distinct from the overall erythrocyte percentage.