Urine Sample: Treatment, Effect & Risks

A urine sample can be used to detect numerous diseases, as well as drug use and pregnancy, by testing for specific substances in each case. Urinalysis is an important area of laboratory medicine, but rapid tests are also becoming increasingly common: not only for pregnancy checks, but also for initial tests for diseases. Bacteria are analyzed, as well as the concentration of red blood cells, sugar and protein in the urine.

What is a urine test?

A urine sample can be used to detect numerous diseases, as well as drug use and pregnancy, by testing for specific substances in each case. Urine sample refers to the emission of urine (from the old German haran; “the excreted”) for subsequent diagnosis. Urine is secreted by the urinary tract in humans as in all mammals. The fluid contains water, various mineral salts and end products of protein metabolism. Its composition varies not only according to the age and sex of the patient, but also according to the amount and type of food consumed. In addition to these naturally occurring components in the urine, pathological urinary components can also be identified by analyzing the urine in the case of diseases, which then allow conclusions to be drawn about these diseases. The amount of urine required for diagnosis varies according to the examination objective applied.

Function, effect, and objectives

Urine tests are used to gain knowledge about possible diseases, drug use, doping or pregnancy. Even if the rapid tests available in pharmacies are now far advanced: Their results provide only clues. Complaints as well as results of self-performed rapid tests should therefore always be discussed with a doctor. Doctors also regularly carry out rapid tests in order to be able to make an initial diagnosis. The rapid test is one of the routine examinations in general practices and is used, for example, for preliminary examinations during pregnancy, before operations, but also for pain in the abdomen, stomach and back. Other reasons for urine tests are pain during urination or blood accumulation in the urine. It is also possible to determine the sugar level in the urine in cases of diabetes. The test strips used can indicate the concentration of blood, sugar or glucose or nitrite in the urine by their coloration, provided they are divided into several parts. Nitrite represents a breakdown product of bacteria and indicates an infection of the urinary tract. Gucose in urine may occur during pregnancy or in some cancers. However, glucose usually indicates diabetes mellitus. Also relevant for diabetics is the detection of ketones: These do not normally appear in urine and can be a result of intensive fasting as well as an indication of an unbalanced metabolism in diabetics. If red blood cells are detected in the urine, inflammation of the urinary tract has probably occurred. In very rare cases, a tumor may also be present, such as kidney or bladder cancer. White blood cells in the urine allow conclusions to be drawn about an inflammation of the bladder or kidneys. In healthy people, there should be little or no protein in the urine. An increased protein concentration therefore also indicates a disease of the kidney. Last but not least, the examination of the pH value also allows conclusions to be drawn about urinary tract infections or diabetes. Urine normally has a pH value between 5 and 6. It is slightly acidic. If the pH rises, so the urine is less acidic, the urinary tract may be infected. If the pH drops, it may indicate diabetes. Urine gets its yellowish color from bilirubin, the breakdown product of the blood pigment hemoglobin. If the urine is strongly yellowish in color, this may indicate liver disease. In most cases, however, the coloration of the urine varies according to diet and fluid intake. Only a subsequent microscopic laboratory examination of the urine can provide a reliable explanation. It is significantly more accurate, but also involves more effort and expense and takes correspondingly longer.

Risks, side effects, and hazards

Since the urine sample is only the examination of the urine to be excreted anyway, there are no risks or dangers for the patient.Also, there is no need to warn about any side effects, since it is not an intervention in the body. Nevertheless, there are some peculiarities that should be taken into account. In order to actually enable the examination of the urine, the genital area should be cleaned with water beforehand, for example, in order to avoid subsequent contamination of the urine with bacteria and other substances. For precisely this reason, however, soap should not be used when cleaning immediately beforehand. Although test strips for diseases are now also available in pharmacies, they are no substitute for a urine test by a doctor. Keeping or touching them can also cause bacteria to get onto the test via the fingers, for example, which can then falsify the test image. For a urine test, it is also common, as long as there are no instructions to the contrary, to use only midstream urine. This means that the first portion of the urine should not be used but only the middle portion should be placed in the container. Subsequently, the residual urine should be retained and not end up in the container. This is because the urine may also initially be contaminated by bacteria, which do not allow any conclusion about actual diseases. Many doctors do not draw attention to this separately. It is therefore helpful to keep this in mind or to ask briefly if necessary.