| low affinity platelet factor IV | Cytokine, produced from platelet basic protein, that acts as a growth factor. (18 Nov 1997) |
|---|---|
| absolute CD4 count | The number of helper T-lymphocytes in a cubic millimeter of blood. With HIV, the absolute CD4 count declines as the infection progresses. The absolute CD4 count is frequently used to monitor the extent of immune suppression in persons with HIV. Also called a T4 count. (12 Dec 1998) |
| absolute eosinophil count | <haematology, investigation> A measurement (cells per microlitre) of the number of eosinophils in a blood specimen. This measurement is useful in the evaluation of autoimmune disease, allergies, eczema, leukaemia, asthma and hay fever. Normal absolute eosinophil counts are less than 350 cells/mcl (microlitre). (27 Sep 1997) |
| Addis count | A quantitative enumeration of the red blood count, white blood count, and casts in a 12-hr urine specimen; used to follow the progress of known renal disease. (05 Mar 2000) |
| Arneth count | The percentage distribution of polymorphonuclear neutrophils, based on the number of lobes in the nuclei (from 1 to 5). See: Arneth index. (05 Mar 2000) |
| b and t cell count | A test that measures the respective quantities of B lymphocytes and T lymphocytes. This test is often performed in the analysis of an immune deficiency disorder. Normal values include: 68 to 75% of total lymphocytes are T lymphocytes and 10 to 20% are B lymphocytes. Increased T-cell counts can indicate infectious mononucleosis, acute lymphocytic leukaemia or multiple myeloma. Increased B lymphocytes can indicate chronic lymphocytic leukaemia, multiple myeloma, Waldenstrom's macroglobulinaemia or Di George syndrome. Decreased T-cells may indicate congenital T-cell deficiency, Wiskott-Aldrich syndrome or AIDS. Decreased B-cells may indicate acute lymphocytic leukaemia or a congenital immunoglobulin deficiency disorder. (27 Sep 1997) |
| blood cell count | A count of the number of leukocytes and erythrocytes per unit volume in a sample of venous blood. A complete blood count (cbc) also includes measurement of the haemoglobin, haematocrit, and erythrocyte indices. (12 Dec 1998) |
| blood count | <haematology, investigation> The determination of the proper number of red blood cells, white blood cells and platelets are present in the patients blood. Acronym: FBC (16 Dec 1997) |
| red blood cell count | A normal value is 4.6-6.2 million RBC's per cubic millimetre of blood. This number can increase in cases of dehydration (fluid loss) or severe lung disease. Interestingly, red blood cell counts are much higher in those who live at high altitude, because of the increased demand for oxygen carrying capacity. (27 Sep 1997) |
| viable cell count | Number of cells in a given area or volume that are thriving. (05 Mar 2000) |
| viable count | Measurement of the concentration of live cells in a microbial population. (09 Oct 1997) |
| CD4/CD8 count | The ratio of the number of helper-inducer T lymphocytes to cytotoxic-suppressor T lymphocytes, as measured by monoclonal antibodies to the CD4 surface antigen found on helper-inducer T-cells, and the CD8 surface antigen found on cytotoxic-suppressor T-cells. In healthy individuals, the H/S ratio ranges between 1.6 and 2.2.When the body mounts an immune response, as against a virus or a transplant, the ratio is almost always reduced because of a decrease in the number of circulating helper-inducer cells and an increase in suppressor cells. The CD4/CD8 count has been used to monitor for signs of organ rejection after transplants, and more recently has become a tool for assessing the relative condition of HIV patients. With the CD4 absolute count and the CD4 lymphocyte percentage, it provides a way of gauging the progression from HIV to AIDS. (05 Mar 2000) |
| CD4 cell count | The most commonly used surrogate marker for assessing the state of the immune system. As CD4 cell count declines, the risk of developing opportunistic infections increases. The normal range for CD4 cell counts is 500 to 1500 per cubic millimetre of blood. CD4 count should be rechecked at least every six to twelve months if CD4s are greater than 500/mm3. If the count is lower, testing every three months is advised. (09 Oct 1997) |
| CD4 count, absolute | The number of helper T-lymphocytes in a cubic millimeter of blood. With HIV, the absolute CD4 count declines as the infection progresses. The absolute CD4 count is frequently used to monitor the extent of immune suppression in persons with HIV. Also called a T4 count. (12 Dec 1998) |
| CD4 lymphocyte count | A count of the number of CD4-positive lymphocytes in the blood. Determination requires the use of a fluorescence-activated flow cytometer. (12 Dec 1998) |