count

[kownt]

a numerical computation or indication.

Addis count the determination of the number of erythrocytes, leukocytes, epithelial cells, and casts, and the protein content in an aliquot of a 12-hour urine specimen; used in the diagnosis and management of kidney disease.

blood count (blood cell count) see blood count.

blood count, complete a series of tests of the peripheral blood, including the erythrocyte count, erythrocyte indices, leukocyte counts, and sometimes platelet count.

blood count, differential differential leukocyte count.

erythrocyte count determination of the number of erythrocytes in a unit volume of blood that has been diluted in an isotonic solution, done with an automatic counter such as a flow cytometer. Called also red blood cell or red cell count.

leukocyte count determination of the number of leukocytes in a unit volume of blood, usually after the erythrocytes have been lysed and the blood has been diluted; it may be done either manually with a hemacytometer or electronically. See total leukocyte c. and differential leukocyte c. Called also white blood cell or white cell count.

leukocyte count, differential a leukocyte count that calculates the percentages of different types. See also total leukocyte count.

leukocyte count, total a leukocyte count measuring the total number of all the types in a given volume of blood. See also differential leukocyte count.

platelet count determination of the total number of platelets per cubic millimeter of blood; the direct platelet count simply counts the cells using a microscope, and the indirect platelet count determines the ratio of platelets to erythrocytes on a peripheral blood smear and computes the number of platelets from the erythrocyte count.

red blood cell count (red cell count) erythrocyte count.

reticulocyte count a calculation of the number of reticulocytes in 1 cu mm of peripheral blood, recorded either as an absolute number or as the percentage of the erythrocyte count. It provides a means of assessing the erythropoietic activity of the bone marrow.

white blood cell count (white cell count) leukocyte count.

he·ma·tom·e·try

(hē'mă-tom'ĕ-trē, hem-ă),

Examination of the blood to determine any or all of the following: 1) the total number, types, and relative proportions of various blood cells; 2) the number or proportion of other formed elements; 3) the percentage of hemoglobin. In some instances, hematometry is used to include a determination of blood pressure.

Synonym(s): hemometry

[hemato- + G. metron, measure]

haematometry

An obsolete term for analysis of the blood to determine the number and proportion of cells in the circulation, haemoglobin content and so on; i.e., blood analysis.

In practice, such analyses are approached in an algorithmic fashion, where the first tier is the automated complete blood count (CBC), often by a proprietary device (the “Coulter”); an abnormal CPC evokes a secondary response, a “blood workup”.

he·ma·tom·e·try

(hē'mă-tom'ĕ-trē)

1. Examination of the blood to determine any or all of the following: 1) the total number, types, and relative proportions of various blood cells; 2) the number or proportion of other formed elements; 3) the percentage of hemoglobin.

2. Determination of blood pressure.

[hemato- + G. metron, measure]