What does this urine test mean

What the urine reveals

Normal, fresh urine is usually almost odorless and clear and has a pale yellow to amber color due to the colored degradation products of hemoglobin, the urochromes. Abnormal cloudiness and streaks can indicate organic components such as cells or microorganisms. A heavily foaming urine is caused by a pathologically increased protein content (proteinuria).

Deviations from the normal urine color can already provide initial indications of an illness. A blue-green or pale pink urine is occasionally caused by urinary tract infections (germs of the genera Pseudomonas and Klebsiella). Melanuria, a brown-black discoloration of the urine due to oxidation of melanin precursors in metastatic malignant melanoma (black skin cancer), is rather rare.

An atypical urine color can also have harmless reasons: Consuming large amounts of foods containing vitamin B or β-carotene (raspberries, beetroot, rhubarb, carrots) causes a yellowish to reddish discoloration.

Many drugs can cause a color change. The pharmacist should point this out in order to avoid confusion for the patient. The colors range from yellowish brown (α-methyldopa), red to reddish brown (phenytoin, sulfamethoxazole, phenothiazines, rifampicin) to black (levodopa, metronidazole) and even blue (triamterene, propofol) and green (amitriptyline, indomethacin).

Simple diagnostics with urine test strips

The routine chemical examination of the urine is usually carried out using multi-parameter urine test strips. The advantages are simple handling without laboratory equipment, standardized results that can be read immediately with little effort and good durability of the strips thanks to the use of dry reagents. Test strips immediately provide initial information on the patient's state of health.

Depending on the version, several absorbent test fields are applied to a stable plastic strip. The analytes are detected by a specific chemical reaction with a color change of the test fields proportional to the parameter concentration. The evaluation of the results is based on the comparison with the color scale printed on the storage container. The following parameters can be found in different combinations on urine test strips:

  • specific weight,
  • PH value,
  • Nitrite,
  • Protein, albumin,
  • Erythrocytes, hemoglobin,
  • Leukocytes,
  • Glucose,
  • Ketones,
  • Urobilinogen and
  • Bilirubin.

The test strips provide the "urine status" in the form of qualitative or semi-quantitative results. They are therefore of essential importance in orienting preliminary diagnostics and serve as a starting point for further diagnostics with microscopic, bacteriological or clinical-chemical analyzes of the urine.

Urine diagnostics has its firm place in the early detection (screening) of diseases of the kidneys and urinary tract, the liver, the cardiovascular system and disorders of the carbohydrate metabolism. Regular follow-ups can, for example, help type I diabetics to recognize changes in metabolic status in good time and to be able to react to them. High blood pressure patients with an increased risk of kidney damage benefit from early detection of microalbuminuria. What information do the individual test fields provide and what are the disruptive factors?