Urine examination with test strips
The most common and easiest urine test is the test strip. It is a thin test strip, a few centimeters long, which is briefly immersed in a small urine sample. The best way to test medium jet urine is to discard the first millilitres of urine and the last drops.
There are up to 11 test fields on the test strip, each measuring one of the following common ingredients: A color change of the field on the test strip, which is compared with color tables, indicates the measurement result. This urine test is semi-quantitative, i.e. it shows not only the presence but also whether little, medium or much of a substance has been detected, usually by indicating +, ++ and +++. Blood components and leukocytes indicate damage to the kidneys or the urinary tract.
One indication of bacterial infection is positive nitrite, a breakdown product of bacteria, although some bacteria do not form nitrite and thus evade measurement. Glucose is important in the diagnosis of diabetes mellitus. Ketone bodies indicate ketoacidosis in the context of poorly controlled diabetes.
If the test strip shows bilirubin or urobilinogen, the liver should be examined more closely. A positive protein field and increased special weight indicate a damaged kidney, especially in the form of glomerulonephritis. The pH value should always be determined and is also lowered, for example, in the context of ketoacidosis. As a cheap and quick urine test, the test strip can already provide many important indications of a clinical picture, but final diagnoses usually require further examinations.
- Erythrocytes/Blood
- Nitrite
- Leukocytes
- Proteins
- Ketone bodies
- Glucose
- Bilirubin
- Urobilinogen
- PH value
- Specific gravity
Urine sediment
The urine sediment, or sediment for short, is the second most common urine test after the test strip. It does not examine the substances dissolved in the urine, but only solid components. These are obtained by centrifuging the urine sample and examined under a microscope.
The sediment allows the presence of leukocytes, erythrocytes and especially deformed and damaged erythrocytes to be assessed. In addition, certain cell complexes, called cylinders, can be detected as well as various types of crystals. Pathogens can also be detected directly. The sediment thus provides indications of kidney damage, infections, especially of bacterial origin, or systemic diseases, including tumors.
