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A urine test is called a urinalysis (the analysis of the urine). It provides information to healthcare providers to diagnose certain medical conditions. Urine tests are most commonly done to diagnose urinary tract infections. But they can also be used to detect medical conditions such as diabetes and kidney disease. 

A urinalysis involves collecting a urine sample and sending it to a laboratory for testing. At the lab, technicians check urine samples for appearance and content. 

Results of a urine test are usually available within a few days. Your doctor may make a diagnosis and prescribe treatment based on the results. Sometimes, the results of a urinalysis lead to more testing, such as a blood test or imaging, to find the problem.

Importance of Urinalysis

A urinalysis can provide important information to your healthcare team, such as:

• Health screening. Your doctor may order a urinalysis as part of a routine medical exam to screen for chronic conditions such as diabetes or kidney disease. A urine test may also be done as part of a pre-surgical evaluation or prenatal care in pregnant women. 

• Diagnosis of a medical condition. Your doctor may want to check a urinalysis if you have symptoms that suggest a specific medical condition. For example, a bacterial urinary tract infection with symptoms such as back pain, painful urination, frequency, and blood in urine.

• Monitor an existing health condition. Your doctor may order urine testing from time to time if you have been diagnosed with a condition such as kidney disease. The results of the test can tell your doctor if the treatment is working and if the condition is progressing. 

• Urine pregnancy test. A hormone called human chorionic gonadotropin (HCG) can be detected in the urine of women who are pregnant as early as 10 days after conception. These pregnancy tests can be performed at home.

• Urine drug tests. These tests screen for the presence of prescription or illicit drugs in a urine sample. They check for other substances that are not checked in a routine urinalysis.

Types of Urine Tests

Urinalysis involves checking three main things - a visual exam, a urine dipstick test, and a microscopic exam.

Visual Examination

When you submit a urine sample to the lab for testing, the technician first examines its appearance and odor. Normal urine is clear to pale yellow and does not have a strong odor. 

Cloudy urine can be a sign of urinary tract infection. The presence of protein in urine can make it appear foamy. Blood in urine can give it a brown or red color. 

Certain foods can give urine an unusual color, for example, red-tinted urine from eating beets. Certain drugs can also change urine color, for example, orange-red urine in people who are taking phenazopyridine (AZO). 

Sweet-smelling urine can be a sign of uncontrolled diabetes. Certain metabolic disorders and liver disease can result in musty-smelling urine. Foods such as asparagus can give your urine an unusual odor. 

Dipstick Tests

A urine dipstick test is done using a plastic tube with a variety of chemicals on it that change color based on the presence of certain substances or above-normal levels of certain substances in the urine sample. This urine test can give your doctor information such as:

• Urine Concentration. Concentrated urine is often a sign of dehydration (not drinking enough fluids). 

• pH level. Changes in urine acidity or alkalinity are measured with a pH level and may indicate a urinary tract or kidney problem.

• Blood in urine may be a sign of kidney damage, bladder stones, kidney stones, infections, bladder cancer, or blood disorders.

• Glucose (sugar) in urine can be a sign of diabetes.

• Protein at high levels might indicate kidney problems. 

• Ketones in urine at high levels can be a sign of diabetic ketoacidosis (a complication of diabetes). 

• Bilirubin is a substance that is made when the liver breaks down RBCs. The presence of bilirubin in urine can be a sign of liver disease. 

• Nitrites or leukocyte esterase in urine may be signs of a urinary tract infection.

Microscopic Exam

A lab technician can look at a few drops of concentrated urine under the microscope. This is called a microscopic examination. It can give clues to your doctor about what might be going on:

• Leukocytes (white blood cells), which may be a sign of infection

• Erythrocytes (red blood cells) can be present in the urine of people with kidney disease, bladder cancer, or a blood disorder 

• Microorganisms such as bacteria, fungi, or parasites which indicate an infection

• Tube-like proteins called urinary casts may be seen in people with kidney problems.

• Epithelial cells may be present if the urine sample is contaminated or be a sign of a medical condition such as an infection or kidney disorder.

• Crystals in urine can be a sign of kidney stones.

Urine Culture and Sensitivity

Urine cultures are done to identify microorganisms in urine. Specifically, a sample of urine is observed in the laboratory for 72 hours to check for the growth of specific bacteria. Besides the urine culture,  the urine test also provides sensitivity analysis, which determines the effectiveness of antibiotics against the identified bacteria. 

24-Hour Urine Test

The 24-hour urine test can be performed during a hospital stay or at home, where the patient collects their urine for a 24-hour period. It can help in the diagnosis of kidney problems by measuring proteins, minerals, and chemicals in the 24-hour sample.

Substances Detected in Urine Tests

Normal Components

Urine is 95% water. Other components of normal urine include urea (a nitrogen-containing waste product), mineral ions like sodium, potassium, and chloride, and other organic and inorganic compounds. 

Abnormal Findings

Abnormal findings in urine are usually referred to with the suffix -uria. Common types of abnormal components in urine include:

• Dysuria: Pain with urination can be present in people with urinary tract infections.

• Polyuria: An abnormally large volume of urine, which may be present in people with diabetes.

• Oliguria: An abnormally small volume of urine seen in people with dehydration, kidney damage, or shock.

• Proteinuria: High levels of protein in urine are often a sign of kidney damage.

• Hematuria: Blood in urine may be seen in infections and kidney or bladder cancer. 

• Glycosuria: Glucose or sugar in urine may be a sign of high blood sugar or kidney damage. 

Health Conditions Diagnosed by Urine Testing

Urinary Tract Infection (UTI)

In people with a urinary tract infection (UTI), a urinalysis test may show white blood cells, red blood cells, and bacteria. If a bacteria is present in the urine, the urine culture helps identify the type of bacteria causing the infection.

Kidney Diseases

Abnormal urinalysis results showing the presence of blood or protein in urine might point to kidney disease. Blood in the urine can be a sign of a kidney or urinary tract disorder such as an infection or cancer. Protein in the urine for three months or longer is a sign of kidney disease. Your healthcare provider will repeat your urine test to confirm these abnormal findings. 

They may order follow up testing, including a blood test to estimate glomerular filtration rate (GFR). This test measures a waste product called creatinine. Another test done to diagnose kidney diseases is albumin-to-creatinine ratio (ACR).

Additional testing with imaging tests such as ultrasound or CT scan can show calculi (stones), tumors, and other problems in your kidneys and urinary tract. 

Diabetes and Metabolic Conditions

Normal urine has very little or no glucose. If glucose is detected in your urine sample, it is an abnormal finding and is called glycosuria. It might mean you have diabetes. Your doctor will order further tests if you have positive results. A urine sample may also contain markers that could point to conditions such as high blood pressure, for example, a sodium to potassium ratio.

Sexually Transmitted Infections

Urine tests to detect sexually transmitted infections caused by bacteria, such as chlamydia and gonorrhea, are widely available. You can do these tests at home and send the sample to the lab. Urine testing for trichomoniasis, HPV (human papillomavirus), and HIV (human immunodeficiency virus) are less common.

Cancer

Blood in urine is called hematuria. It is an abnormal finding and might be present due to kidney injury, kidney stone, prostate problems, or cancer. In addition to urine tests, your doctor rules out different diagnoses based on other lab results and symptoms. If blood is detected, and UTI, kidney injury, and prostate problems are ruled out, your provider may order urine cytology, which is a test in which the microscopic aspects of a sample of urine are examined to look for abnormal cancer cells. 

In addition, healthcare providers can check urine for tumor markers, which are substances made by cancer cells or made by the body in response to cancer. 

Cystoscopy is a test done using a thin tube with a camera attached at its tip. It allows your urologist to look inside your bladder and urethra and check for any abnormal areas. They can also take a tissue sample for biopsy.

Drug and Substance Screening

A urine drug screening is a common test done to detect substances that are not normally present in urine (prescription drugs and other substances like illegal drugs). How long after drug use this test detects a substance depends on the type of drug used, how much you used, how long you’ve been using it, and your body’s reaction to it. Some of the drugs that can be detected on urine drug tests include:

Medications 

• Barbiturates, such as phenobarbital and secobarbital

• Benzodiazepines, such as alprazolam or clonazepam

• Opioids such as morphine, codeine, oxycodone, hydrocodone, and fentanyl

Illegal Drugs

Urine drug testing is most commonly performed for:

• Amphetamines and methamphetamine

• Cocaine 

• Marijuana (THC)

• Phencyclidine (PCP)

• Opiates

• Ecstasy

• Performance-enhancing substances such as steroids

Alcohol

A urine drug test for alcohol checks for the presence of a substance called ethyl glucuronide or EtG, which is formed when the liver metabolizes ethanol. EtG can be detected in the urine much longer than alcohol in the breath or blood. Typically, EtG may be present in the urine up to 48 hours after a few drinks and up to 72 hours after heavy drinking.

Interpreting Urine Test Results

A urinalysis alone cannot provide a definite diagnosis. However, the results of your urine tests give your healthcare provider clues and help them plan the next steps to take. They might order other tests, such as blood tests or imaging studies, before reaching a definitive diagnosis and prescribing treatment. 

False positive results and false negative results are possible. False positives means a particular substance that is not actually present is detected on urinalysis. False negatives mean a substance that is present is missed. Your doctor will order repeat testing to confirm abnormal results.

Note: Getting negative results on a urinalysis does not guarantee that you don’t have a health problem. A health condition may be in the early stages where there are some early signs but it is not detectable in urine. Urinalysis is not a specific test for a medical condition, but rather provides clues. Your healthcare provider will base their interpretation of your urinalysis results on your symptoms and other test results.

Following Up on Abnormal Findings

It’s important to keep all your medical and laboratory appointments after a urinalysis test. If you have abnormal results, your doctor may prescribe treatment or order further testing. For example, white blood cells on a urine test can be a sign of infection. In this case, your provider may order a urine culture and sensitivity test to check for a urinary tract infection (UTI).

Conducting and Preparing for a Urine Test

The method of collecting a urine sample for testing is called a clean catch method. This method collects the middle of the urine stream and prevents germs from the vagina or penis from getting into the test sample.

How to Collect a Urine Sample for a Urine Test

Girls and Women:

• Spread the labia (lips of the vagina) with your fingers. Wipe the area between the labia with a sterile wipe, wiping from front to back. Use another wipe to clean the opening of the urethra (from where urine comes out). 

• Urinate a small amount into the toilet bowl.

• Stop the flow of urine and hold the sterile urine cup a few inches from your urethra. Urinate into the cup until it is full.

• Finish urinating in the toilet bowl.

Boys and Men:

• Clean the tip of the penis with a sterile wipe. Uncircumcised boys and men should pull back the foreskin and clean the head of the penis. 

• Urinate a small amount into the toilet bowl.

• Stop the flow of urine and urinate into the sterile urine cup. 

• Finish urinating into the toilet bowl.

After collecting the sample for your urine test, close the lid tightly without touching the contents or the inside of the lid or cup. Give the sample to your healthcare provider. If you are doing the urine test at home, place the cup in a plastic bag and store it in the refrigerator until you are ready to take it to the laboratory.

Common Questions

What does 3 mean on a urine test?

If 3 or more RBCs (red blood cells) are seen per high power field on microscopic examination of a urine sediment, a diagnosis of hematuria (blood in urine) is made. 

What diseases can be diagnosed by urinalysis?

Doctors can use the results of a urinalysis, along with other test results, to diagnose conditions of the urinary system as well as metabolic processes. For example, urinary tract infections, sexually transmitted infections, diabetes, kidney problems, and certain types of cancer. 

What are some examples of abnormal findings in a urinalysis?

Some examples of abnormal findings on urinalysis include unusual appearance (cloudy or foamy urine, blood in urine) and unusual odor (sweet smelling or musty smelling urine). A positive result for blood, glucose, proteins, or ketones in a urine sample is also abnormal findings. In addition, alcohol and other drug tests can detect abnormalities in a urine sample (detect substances that should not be present).

What abnormal substances can be detected in urine tests?

Some of the abnormal substances that can be detected on urine tests include blood in urine, protein in urine, glucose in urine, prescription drugs, and illegal drug use.