Urinalysis: what a urine test can show

What the test measures

A full urinalysis, sometimes written "U/A" or "urine routine" on the request form, usually has three parts.

1. Physical look

The lab notes the colour and whether the urine is clear or cloudy. Cloudiness can come from infection, but also from harmless crystals.

2. Dipstick (chemical test)

A plastic strip with small coloured pads is dipped into the urine. Each pad changes colour according to what is present:

3. Microscopy

The urine is spun down and the sediment is looked at under a microscope. The lab counts red and white blood cells and looks for casts (tiny tube-shaped clumps formed inside the kidney), crystals, bacteria, yeast and, in some settings, parasite eggs. In coastal Kenya, microscopy may also be used when schistosomiasis (bilharzia) is a concern, since it can cause blood in the urine.

Why it is ordered

Urinalysis is quick and inexpensive, so it is used widely: to check for a urine infection, as part of antenatal care, in routine check-ups, for people with diabetes or high blood pressure, and when someone notices blood in the urine, foamy urine, pain when passing urine or swelling. It is a screening test. An abnormal finding usually leads to a more specific test rather than a final answer.

How the sample is taken and how to prepare

The lab will give you a clean container. For the most reliable result, give a clean-catch midstream sample:

1. Wash your hands and clean the genital area with water.
2. Start passing urine into the toilet.
3. Without stopping the flow, collect the middle part of the stream in the container.
4. Finish passing urine into the toilet, then close the lid firmly.

The first urine of the morning is often preferred because it is more concentrated. Deliver the sample to the lab quickly, ideally within about two hours, or keep it cool if there will be a delay. Urine left in the heat of a Mombasa afternoon can grow bacteria and give a misleading result.

If possible, avoid testing during a period, and tell the lab if you are menstruating. Heavy exercise just before the test can also cause small amounts of protein or blood to appear.

How results are reported

Dipstick results are usually reported as negative, trace, 1+, 2+, 3+ or 4+. These are rough grades, not precise measurements. Some labs also print an approximate concentration next to the grade. Specific gravity is shown as a number such as 1.015, and pH as a number such as 6.0.

Microscopy results are usually reported as the number of cells seen in each high-power field of the microscope (written "/HPF"), for example "RBC 0-2/HPF". Casts and crystals are described by type. As with all tests, the lab's own reference range on your report is the one to use.

What can affect the result

• Sample handling. A sample that is not midstream, or is delivered late, can show white cells or bacteria from contamination rather than infection.
• Concentration. Very dilute urine can make protein or blood look lower. Very concentrated urine can make them look higher.
• Menstruation can make the blood pad positive.
• Exercise and fever can briefly cause protein in the urine.
• Some foods, vitamins and medicines change urine colour or interfere with certain pads. Tell the lab what you are taking.

What urinalysis cannot tell you on its own

A urinalysis is a first look. It has clear limits:

• The protein pad misses small amounts of albumin. A dipstick that reads negative for protein does not rule out early kidney damage. The urine ACR test is much more sensitive and is the test KDIGO recommends for measuring albuminuria.
• It does not confirm infection on its own. A urine culture, a separate test that grows bacteria in the lab over a day or two, identifies the germ and which medicines it responds to.
• It does not measure kidney filtration. That needs a blood test for creatinine and an eGFR.
• It does not find the cause of blood in the urine. Blood can come from the kidneys, bladder or urethra. Further tests, sometimes including an ultrasound, may be needed.

Related tests

• Urine ACR: measures albumin in the urine accurately.
• Kidney function tests: blood tests for urea, electrolytes and creatinine.
• Kidney ultrasound: looks at the structure of the kidneys and bladder.
• Urine culture: confirms and identifies a urine infection.

When to discuss your result with a clinician

Discuss your result with a doctor or clinical officer if protein or blood is found, especially on more than one test, if glucose appears in the urine, or if you have symptoms such as burning when passing urine, fever, foamy urine or swelling. Protein or blood that persists on repeat tests needs follow-up even if you feel well. The pages on protein in urine and changes in urination explain the usual next steps.

This page explains what a test or condition involves. It is not a diagnosis and does not replace advice from a doctor who knows your history. Your results should be interpreted together with your symptoms, other tests and a clinical assessment. Medical disclaimer.