How to test for urinary tract infection and when to see a doctor

 Key takeaways:

• Testing for a urinary tract infection (UTI) may require performing urine tests, lab tests, blood tests, imaging, and sometimes cystoscopy. The type of test to be carried out depends on its severity.
• While most UTIs are easy to treat, some are complicated and harder to treat. It’s best to see a doctor if UTI symptoms persist or worsen or if you experience severe symptoms like intense abdominal or back pain, fever, or blood in your urine.
• The type of doctor to see for UTI depends on the part of the urinary system affected and the severity of the condition. Doctors who treat urinary tract infections include a general practitioner, a gynecologist, a urologist, or a nephrologist.

Urinary tract infection (UTI) is the most commonly diagnosed infection, affecting approximately 150 million people worldwide every year.  The parts of the urinary system most commonly affected by infection are the kidneys, ureters, bladder, and urethra. Urinary tract infections are mostly caused by bacteria, but some are also caused by fungi.

The first thing some people do when they suspect they have a UTI, aside from reaching out to their doctors, is to carry out an at-home UTI test using an over-the-counter test strip. This article explains how doctors test for UTIs, how to test for UTIs at home, how to read your test results at home, and when you should consider seeing a doctor.

 How doctors test for urinary tract infections

When it comes to testing for urinary tract infections, doctors use different methods to diagnose UTIs. Here's an overview of the different tests available for UTI.

 1. Lab urine test for UTI

A lab urine test, also known as a urinalysis, is the primary method doctors use to diagnose UTIs. This test analyzes a urine sample in a lab to identify signs of infection.

Before a lab urine test is carried out, the laboratory personnel will instruct that you wash your hands using soap and water and wash your genital area with plain water. They will ask you to discard the first part of the urine and collect midstream urine in a sterile container provided, which they will later send to the lab for testing.

The urine sample is then visually examined in the lab for color, cloudiness, and concentration. This helps your doctor detect abnormalities that suggest an infection. For instance, cloudy or foul-smelling urine can be a sign of a UTI.

They will also place a  small amount of the urine sample under a microscope and analyze it for the presence of red blood cells, white blood cells, crystals, epithelial cells, and bacteria. This process helps to detect the particular microorganisms that may be present in your urine.       

The doctor may also request a urine culture. This is used to find out the kind of bacteria causing the UTI infection. It takes about 24 to 48 hours for the test to be completed.

Not everyone with a UTI needs a urine culture. But in certain situations, like when someone keeps having a recurrent UTI, their doctor may request that they go for a urine culture.

 2. Blood test for UTI

While urinalysis is the primary test for diagnosing a UTI, blood tests can also be used in certain situations. Blood tests help evaluate an individual's overall health and determine if the infection has spread to other places in the body. Common blood tests include:

• Complete blood count (CBC): This blood test measures the levels of different blood cells, including white blood cells (WBCs). An increase in the WBC count may suggest an infection.
• Blood culture: This test involves collecting blood samples, which are checked for bacteria. The samples are then placed in a special liquid and observed over five days to see if bacteria grow. Blood culture is only done if your doctor suspects that the bacteria has spread to the blood, as this will help guide your doctor in choosing the right antibiotics for treatment.

 3. Imaging test for UTI

An imaging test is used to assess the urinary tract for any structural abnormalities. This test provides a clear picture of the urinary system. If you have repeated infections, difficulty emptying the bladder, accidental leakage of urine, pain in your lower back or upper back, or blood in the urine (hematuria), your doctor may recommend imaging tests.

This test can help your doctor detect conditions such as kidney diseases, tumors, kidney stones, or structural abnormalities. Imaging tests may include procedures like ultrasound, CT scans, or magnetic resonance imaging.

 4. Cystoscopy for UTI

This test involves inserting a thin, flexible tube with a camera (cystoscope) into the urethra and bladder. It allows doctors to see the urinary tract clearly and assess for abnormalities, such as bladder stones or bladder tumors.

Cystoscopy is mostly performed when there are recurrent or persistent UTIs. The presence of blood in the urine, or other suspected issues that need closer examination is also an indication for this procedure.

 Can you test for UTI at home?

Yes, there are at-home test kits available for testing urinary tract infections (UTIs). These kits typically include test strips or dipsticks that can detect certain markers in the urine that may be associated with UTIs. 

At-home UTI test kits work by analyzing the levels of nitrites and leukocytes in the urine. Nitrites are produced by certain bacteria associated with UTIs, while leukocytes are white blood cells that increase when one has an infection.

However, it is important to note that at-home UTI test kits have limitations and may not provide the same level of accuracy as a laboratory-based urinalysis.

 How to do at-home tests for UTI using OTC dipstick

Here is how to test for a urinary tract infection at home using the OTC dipstick:

• Read and understand the instructions provided on the UTI test kit. 
• Wash your hands thoroughly with soap and warm water. 
• Wash your genital area with plain water; avoid using soap.
• Use a clean container to collect midstream urine (urine that is in-between). 
• Open the dipstick package and remove a test strip. 
• Be careful not to touch the testing area (usually located on one end of the strip) with your fingers.
• Dip the testing area of the dipstick into the urine you collected. 
• Ensure that the testing side is inside the urine for the specified time, as mentioned in the instructions. 
• Avoid exceeding the recommended dipping time.
• Remove the strip and gently shake off excess urine to prevent inaccurate results.
• Place the dipstick on a clean, non-absorbent surface or on a provided test result area. 
• Follow the instructions regarding the waiting time for the results to develop; this takes a few minutes.

 How to read urinary tract infection test strips

Examine the test strip for any color changes in the testing areas. Each test strip has different markers, such as nitrites or leukocytes. These markers, if present, may suggest you have a UTI.

Use the chart on the test strip package to interpret the results. This will guide you in interpreting the results and the next actions you should take. This action may include seeing a healthcare professional.

 When to see a doctor for a urinary tract infection

You should see a doctor for urinary tract infection concerns if you notice any of the following:

• Your temperature is very high, or you feel hot and shivery. 
• You have a low temperature below 36°C.
• You are confused or drowsy. 
• You have pain in your lower tummy or the back, just under the ribs.
• You can see blood in your pee.
• Your symptoms are severe or getting worse.
• Your symptoms haven’t started to improve after a few days.
• You get UTIs frequently. 
• Your symptoms come back even after treatment.

If you have a UTI, you should start by seeing a general practitioner closer to you. They serve as the first point of contact. Your doctor will perform assessments and urine tests to diagnose you and then prescribe appropriate medications. 

For females who regularly develop UTIs, their doctors may refer them to a gynecologist.  People who have recurrent UTIs due to abnormalities in their bladder, kidneys, or urethra are primarily treated by a urologist. On the other hand, a nephrologist mostly treats UTIs that occur in the upper part of the urinary tract, up to the kidneys. They also treat any complications that may arise due to infection in those areas.

The type of doctor you choose to see depends on the part of the urinary system affected and the severity. If you're not sure, you can start by seeing your general practitioner, who can refer you to a specialist if the need arises.