It is no secret to anyone that for the accurate diagnosis of almost any disease, a laboratory study of body fluids is necessary. And a fairly clear picture of the state of the excretory system gives urine. Its pH can help in the diagnosis of inflammatory and infectious diseases.
What is urine pH?
The human excretory system is responsible not only for removing excess fluid and toxins from the body, but also ensures normal acid-base balance. It is this criterion that allows you to determine urine.
PH is the so-called hydrogen indicator, which shows the number of hydrogen ions in the solution (in this case, the solution is a urine sample). Such an analysis allows you to determine the physical properties of urine, as well as to assess the balance of alkalis and acids that it contains. The results of such studies are extremely important for diagnosis.
What does this indicator depend on?
In fact, there are many factors that can affect the chemical composition of urine. In particular, pH is highly dependent on human nutrition. In people who use the so-called "heavy food", which contains proteins, sulfur and phosphorus, the urine reaction is acidic (less than 5). If the human diet includes mainly vegetable and dairy products, then the urine reaction will be alkaline (more than 7).
In addition, there are other factors under the influence of which urine changes. PH may vary depending on the characteristics of the metabolism. The chemical composition is affected by any inflammatory diseases of the excretory system. The digestion process is also important, in particular, a decrease or increase in the acidity of the stomach. Some drugs may affect pH.
It is worth noting that the optimal level of hydrogen ions contributes to the normal sanitation of the bladder, and also inhibits the vital activity of pathogenic microorganisms, thereby reducing the likelihood of developing an infectious disease.
When is a urinalysis prescribed?
To date, urine is the most common research sample. PH helps determine the presence of a mass of diseases. That is why such tests are prescribed to all patients with suspected infectious and inflammatory diseases of the genitourinary system, as well as with a number of other disorders, including metabolic failures.
A urinalysis is also prescribed during annual preventive medical examinations. Sometimes such studies help diagnose the disease before the onset of external symptoms.
Urine samples are recommended to be taken after a previous infectious disease, especially if it is caused by streptococci - this makes it possible to determine the presence of complications.
How to pass urine?
In order for the analyzes to be as truthful as possible, it is worth observing some rules. The most informative are morning urine samples. The day before, it is not recommended to eat food that can change the physical properties of a liquid, in particular carrots and beets. In addition, you can not take diuretics or decoctions, as this can affect the chemical composition of urine.
Before sampling, it is necessary to wash the genitals - otherwise the samples will have too many epithelial cells, which will complicate laboratory research. It is advisable to collect median urine.
Another important point - you should not conduct a similar study for women during menstruation, since menstruation can distort the test results. Only compliance with these rules will help to conduct a urine test as accurately as possible - the pH will be true.
How is urine pH determined in the laboratory?
The easiest way to study the acid-base balance is to use special indicators. Most often, urine pH is determined using litmus paper, which changes color depending on the reaction of the solution. Each color corresponds to a specific pH value. This method allows you to determine the indicator with an accuracy of 0.5.
There are other, more accurate ways in which urine is examined. PH can be determined using an ionomer (pH meter). This method is more convenient and is characterized by higher accuracy (up to 0.01 units).
Since the pH can vary throughout the day, for better accuracy, some patients are advised to measure pH for seven consecutive days.
What is the urine pH?
Depending on the results of the study, doctors make assumptions about the form and severity of the disease. But what is a normal urine pH? Again, this indicator depends on the diet, medication taken, the age of the patient.
In a healthy person, the reaction of urine ranges from slightly acidic to neutral. Depending on the characteristics of the diet, this indicator can be 4.5 - 8.0.
The pH of urine in newborns is lower and ranges from 4.5 to 5.9. In premature infants, this indicator drops even lower - 4.8 - 5.4.
What is the evidence of a high urine pH?
Many people are interested in questions about when alkalization of urine occurs. As already mentioned, a similar phenomenon is observed when eating vegetable and dairy products, alkaline mineral water. The increased acidity of the stomach and frequent vomiting, which leads to the loss of water and chlorine by the body, leads to the same result.
On the other hand, there are many diseases in which urine changes. PH rises with many infections of the excretory system. In particular, this happens with cystitis, pyelonephritis and other diseases. It is known that some bacteria cause the breakdown of nitrogen-containing compounds to ammonia, which, in turn, increases the alkalinity of urine.
The same picture is observed in chronic renal failure. An increase in pH may be caused by the use of certain drugs, in particular bicarbonates, adrenaline and nicotinamide. The same thing happens against the background of parathyroid hyperfunction , hypoaldosterism and hyperkalemia.
Why does a decrease in pH (acidification of urine) occur?
A decrease in the pH and acidification of urine occurs in some infectious diseases of the excretory system, in particular those caused by the activity of tuberculosis microbacteria and Escherichia coli.
The cause may be increased acid formation in the body. This happens with prolonged starvation, alcohol abuse, sepsis, shock, intense physical exertion, and diabetes.
Naturally, such a change can be caused by taking medications - methionine, ascorbic acid, corticotropin, calcium and ammonium chloride, arginine hydrochloride.
Urine acidification can be caused by a decrease in the level of bicarbonates in the blood buffer system, which is observed with severe diarrhea, ureterosigmostomy. Primary and secondary hyperaldosteronism, nephrotic syndrome, hypokalemia, multiple myeloma, cystinosis, heavy metal poisoning - all these disorders lead to a decrease in the hydrogen index.
Naturally, a urine test alone is not enough to make an accurate diagnosis. Moreover, not only urine pH is taken into account, but also the presence of proteins, salts, blood cells, etc. Urinalysis is only part of the diagnostic process, which allows you to evaluate the functioning of the excretory system.