Cloudy Urine: Causes of Turbidity and What It May Mean

Your urine has become cloudy — and you immediately recalled all the scary words you have ever heard about kidneys. Let's sort this out calmly: turbidity can be a sign of a urinary tract infection or have another cause. There is no shame here: urine is just as much a biological fluid as saliva or blood, and doctors assess its appearance every day.

What urine should be like and what its clarity depends on

Normally, urine color ranges from straw-colored to deep yellow. It is determined by coloring substances — urochromes — and the more intense the color, the more concentrated the urine. Pale urine is usually less dense and is passed in larger amounts.

Daily urine output in an adult with a normal diet is about 1.5–2 liters, which is 70–80% of the fluid consumed.

Causes of cloudy urine

The doctor assesses more than just turbidity. If the only symptom is dark urine or odor, it may be due to insufficient drinking. Salts can also precipitate in the urine, especially if the sample has been cooled.

Another group of causes is inflammation. Cloudy urine is among the typical symptoms of a urinary tract infection, along with pain or burning during urination. With an infection, the urine may smell bad or contain blood.

The third group is changes in composition: a grayish-white color of urine can be due to pus (pyuria), and persistent abundant foam after shaking — due to protein admixture.

Urinary tract infections are the second most common type of infection in the body. Women are affected about four times more often than men: in women the urethra is shorter, making it easier for bacteria to reach the bladder. The risk is higher with diabetes, with a catheter in the bladder, and with spinal cord injury.

Cloudy urine with white sediment: what it may be

A grayish-white color of urine may be associated with pus (pyuria), and a milky appearance — with a high fat content. Salts can also precipitate if the sample has stood or cooled, and the laboratory may mistake them for kidney pathology. What exactly the sediment is is determined by the test. That is why urine is transported to the laboratory only at above-freezing temperatures, and a frozen sample is collected again.

With which symptoms cloudy urine indicates an infection

Turbidity alone, without other complaints, does not allow one to judge the cause: this is determined by the doctor based on the test. Infection is suspected when something from the list is added to the turbidity:

• pain or burning during urination;
• urges more often than usual, including at night, or sudden and very strong;
• aching pain in the lower abdomen or in the back just below the ribs;
• high temperature, chills, feeling hot or cold;
• blood in the urine — pink, red, or dark brown.

In older people with memory impairment and in people with a catheter, infection may manifest differently: confusion, agitation, incontinence that has worsened compared with usual, new chills. In children — fever, lethargy, refusal to eat and drink, wet bed.

What a urine test shows with turbidity

A general urine test includes assessment of physical properties, chemical and biochemical testing, sediment microscopy, and microbiological testing. Morning urine is taken for the test: it has been collecting in the bladder all night, and the values are more objective. First they wash, then collect urine into a sterile container from the pharmacy. It must be delivered to the laboratory within 1.5 hours after collection.

Based on the result, the doctor looks for inflammation cells, bacteria, salts, and protein in the urine. Separate tests clarify the picture: urine culture for bacteria, nitrite test, leukocyte esterase test. In chronic infection, the test does not always find the causative agent, while symptoms persist.

When to see a doctor

See a doctor if you are 65 years old or older, if a child or adolescent under 15 is ill, if the temperature is very high or below 36C and you have chills, if you are a man, if you have diabetes or weakened immunity, if you wear a catheter, if you are pregnant. Separate reasons are pain in the lower abdomen or in the back below the ribs, blood in the urine, symptoms rapidly worsening or not resolving within 48 hours after starting treatment, recurrent infections: two in six months or three in 12 months.

Some of these signs indicate a possible kidney infection. It is dangerous: without treatment it can progress to sepsis.

Cloudy urine by itself is not a reason to call an ambulance. 103/112 — if a person with a urinary tract infection is confused, drowsy, or has difficulty speaking. These are signs of a severe condition that can end in sepsis.

This material is for reference: it helps to understand what to think about, but does not replace a doctor's consultation — the decision on examination is made by a specialist who sees you and your test results.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer