Addis Count

Addis Count

Definition of ADDIS COUNT

A technique for the quantitative determination of cells, casts, and protein in a 12-hour urine sample used in the diagnosis and treatment of kidney disease.

Biographical Note for ADDIS COUNT

Addis, Thomas (1881–1949), American physician. Addis is most notable for his work in pathology and in particular for the study of kidney function. In 1925 he presented his method for counting cells in urinary sediments. The resultant figure is used to diagnose pathological conditions in the kidney and is now known as the Addis count. He is also known for his test, first reported in 1922, for determining the specific gravity of the urine. Addis's other areas of research included blood coagulation, hemophilia, plasma, and glycosuria.

Addis-Kakovsky test: The test is used for quantitative determination of the formed elements in the urinary sediment. Urine collected during 12 hours is stirred thoroughly, its amount is measured and a 12-minute aliqudt (l/50th of the full volume) is placed in a graduated centrifugal test tube. ( After centrifuging for 5 minutes at 2000 rpm the supernatant is removed by a pipette, while the remaining 0.5 ml sediment is stirred and transferred in­to a cell for counting blood formed elements. Leucocytes, erythrocytes, and casts are counted separately. The quantity of cells counted in one microlitre is multiplied by 60 000 to find the quantity of the formed cells of the urine excreted during the day. The normal counts are 1 000 000 for erythrocytes, 2 000 000 for leucocytes, and 20 000 for casts.

Nechiporenko's method: Nechiporenko's method is now widely used to count erythrocytes and leucocytes in 1 ml of urine. The main advantage of this method is that an average sample of urine is taken for analysis and the presence of pus from the sex organs is thus excluded. A disadvantage of the method is that it does not account for diuresis. The normal counts are 1000 erythrocytes, 4000 leucocytes, and 220 hyaline casts.

Bacterioscopic and bacteriological study of urine. Urine cultures are used to establish the infectious nature of a disease of the urinary system. Sterile glassware should be used for the purpose. Whenever necessary, the urine is studied bacterioscopically for the presence of tuberculosis mycobacteria. A smear is prepared frofn the urinary sediment with Ziehl-, > Nielsen staining. The urine is studied bacteriologically to determine qualitative and quantitative composition of its microbial flora. In the presence of bacteriuria, it is very important to determine its degree and microorganism sensitivity to various antibiotics.

This page was last modified on September 14, 2014.