If there is a lot of foam in the urine, could it be a sign of kidney disease?

Foamy urine has long been considered an important warning sign of kidney disease. Many people find that their urine is foamy after using the toilet, which inevitably makes them panic. So how is foamy urine formed? Does foam in urine necessarily mean that there is something wrong with the kidneys?

1. How is foamy urine formed?

Normal fresh urine is a transparent, amber liquid, and the color varies depending on the amount of urine. Under normal circumstances, the surface tension of urine is very low, and fewer bubbles are formed. If a person's urine contains more amphiphilic compounds, namely the hydrophilic end (which likes to be with water) and the hydrophobic end (which hates to be with water), the hydrophilic end that is soluble in water is adsorbed on the surface of water and gathers with the hydrophobic end that is insoluble in water, foam will be formed. In addition, urine contains some organic and inorganic substances, which make the urine tension stronger and some foam will appear. Therefore, the appearance of foamy urine does not necessarily mean that the body is unhealthy. However, due to various reasons, when the composition of urine changes, the surface tension of urine decreases, and the number of bubbles will increase. Proteinuria is a very common situation.

2. Why are bubbles visible in normal urine?

1. Urine concentration: When you drink less water, have diarrhea, or sweat too much, your urine will become concentrated and the substances contained in the urine will increase relatively, which will easily form foamy urine.

2. Suffering from various digestive system diseases: such as hepatobiliary system diseases, taking choleretic drugs, overgrowth of intestinal bacteria, increased excretion of bile salts through urine, etc., will all cause foamy urine.

3. Excessive secretions in the urethra: This is a common situation. For example, if there is semen in the male urethra, foamy urine will form.

4. Urgent urination or high urination position: Urgent urination or urination at a high position may cause strong impact on the urine and form a lot of foam.

5. Other reasons: There are some detergents in the toilet, which can also cause more foam.

3. Abnormal foamy urine

Foamy urine is common in various kidney diseases. About 1/3 of patients with foamy urine are found to have proteinuria, which is a common abnormal manifestation of kidney disease.

1. Proteinuria: If there is a lot of protein in the urine, there will be a lot of foamy urine. This kind of foamy urine is characterized by dense and large amount of foam, like beer foam, and it will not dissipate after dozens of minutes.

2. Urinary tract infection: Urinary tract infection can increase the inflammatory secretions in the urethra, which can increase the foam in the urine. If the infection is caused by some gas-producing bacteria, it can also cause a lot of bubbles in the urine.

3. Increased sugar in urine: Increased glucose in urine will also produce some foam. This is common in diabetic patients, because of increased blood sugar, secondary increase in sugar in urine, resulting in more foam in urine. It can also be seen in some people who eat a large amount of carbohydrates in a short period of time, or receive a large amount of glucose intravenously, which causes a transient increase in sugar in urine and more foam in urine.

4. Various renal tubular diseases: Aminoaciduria can also cause foamy urine, such as Fanconi syndrome, cadmium poisoning, multiple myeloma, etc.

5. Rare diseases: such as vesicocolonic fistula.

4. What to do if foamy urine occurs?

Although foamy urine is a common symptom of kidney disease, it does not necessarily mean that foamy urine is kidney disease. In the end, it is the test results, not the symptoms, that count. It is not recommended to use the amount of foamy urine to measure the amount of proteinuria and the severity of the disease. It is very inaccurate. There are many ways to recheck. You can use urine test strips at home. If you are still worried, the best way to identify is to go to the hospital for a urine test. If not only foamy urine appears, but also accompanied by edema, macroscopic hematuria, increased nocturia, etc., you must go to the hospital in time to find out the cause.