Urine Tests : Examination Of Urine Samples Different Methods Are Used

Urine tests

To attract and examination of urine samples different methods are used. In addition, studies of the formation and excretion of urine, for example, the uroflowmetry (urine flow).

Diseases of the prostate and its complications often affect the urine and micturition (urination) from. So can in inflammation such as prostatitis or an Harnweginfekt bacteria and blood in the urine can be detected (see also acute prostatitis and hematuria ).

Extraction of urine samples

At the beginning of micturition (urination), in the first Harnportion the first urine contains many impurities from the urethra and possibly from the tip of the penis (such as mucus, cells, bacteria). Then those who were stirred up or dissolved already in the bladder therein, and in the end it were the dregs from the bladder. In order to reduce certain admixtures or to isolate their source, urine samples are collected after disinfection of the tip of the penis by catching individual Harnportionen:
Mid-stream urine (MSU): After draining and discarding the first Harnportion a second helping is collected. In many cases, this simplest sample is sufficient.

Two glasses of sample: Here, the first portion (the first 10-30ml) and the second (MSU so) collected separately.

Three-and four-glass test: After collecting the first and second Harnportion the prostate is examined and a little massaging (see also digital rectal examination , DRE). Then the rest of the urine, including prostatic fluid is discharged into a third glass. From the four-glass test is when the secretion is drained through the urethra already in the prostate massage and was collected separately. It is the main way to rule out a bacterial inflammation of the prostate and urinary tract.
Only in very special cases, the urine sample with a catheter endoscopically obtained (in the cystoscopy) or by bladder puncture (removal with a needle through the abdominal wall). And urine is special purpose, namely, the accurate measurement of the quantity of the substance or that the number of molded components at a certain time (3-24 hours) was eliminated. For this, the bladder is completely emptied and then the urine during the collection period (also again at the end of the period!) Collected in containers.

Examination of urine samples

Inspection (viewing): color and transparency of the urine give clues to its composition. For example, it is light to dark yellow depending on the concentration. A red discoloration can be caused by dyes or blood (see hematuria ), a haze of inflammation and foaming of increased excretion of protein.
Test strip assay: These rapid tests measure certain chemical substances and provide quantitative (exact) or semiquantitative ("semi-exact", indicative) values. Most of erythrocytes (red blood cells), leukocytes (white blood cells, inflammatory cells), protein (protein), glucose (sugar), nitrite (sign of bacteria), bilirubin and urobilinogen (degradation products of hemoglobin) and concentration (specific gravity) and acidity ( pH) of the urine.

Microscopic examination: This is formed constituents of the urine can be detected and possibly enumerate, such as crystals, blood cells (red cells), epithelial cells (cells of the Harnwegsoberflächen), sperm (spermatozoa) and bacteria. This is usually done on the basis of (possibly colored) smears of urine sedimentation. It is obtained by centrifugation of urine, which serves to concentrate the solid ingredients.

Bacteriological examination: If you suspect an inflammation is applying to bacterial cultures by applying the urine samples on nutrient media. During incubation (incubation, usually for 24 hours) to share the bacteria and form colonies. These are counted for the indicative enumeration and then possibly spread on special culture media to determine the nature of each pathogen (germ) typing and their resistance (resistance) against antibiotics (antibiogram).If we examine all such portions of a two-, three-or four-glass test (see above), it can be seen from the results, where the focus of inflammation is most likely.

Uroflowmetry (urine flow)

When uroflowmetry the bladder is emptied in the normal way in a meter. It measures the amount of urine drained per second and makes them flow rate (engl. flow) versus time as a curve, justifying can then be the duration of micturition (urination, normal 10-15 seconds), the maximum flow rate (normally 20-50ml read per second) and the quantity of precipitation.

The uroflowmetry is especially adapted to determine an obstacle to the Harnabflusses from the bladder, so the obstructive voiding dysfunction (see voiding dysfunction ). This is particularly important in the benign prostatic syndrome (BPS): The narrowing of the urethra appears as a typical curve with a delayed increase, decreased maximum flow rate and prolonged Miktionsdauer (see examination by BPS ). And the readings are crucial to the type of treatment (see treatment of the BPS ).

Other urine tests

In prostate diseases mentioned methods are usually sufficient. Only in special cases, further investigation of urine or its formation and excretion are required, for example, an accurate determination of excreted cells (cytodiagnostics), a bladder pressure measurement (cystomanometry) and X-ray examinations.