How UTIs Are Diagnosed

Diagnosing urinary tract infections (UTIs) typically involves analysis of a urine sample, and in some cases, imaging tests may be used.

Every year, UTIs account for as many as 8.1 million visits to healthcare providers. These infections can cause a great deal of pain and discomfort, and seeking a diagnosis is the first step in finding relief and preventing potentially serious complications, such as permanent kidney damage.

At-Home Testing

A number of over-the-counter products may help you test for a UTI on your own. The at-home techniques usually involve holding a dipstick (a thin plastic strip with chemicals that change color) in your urine stream and then checking the testing strip for certain changes.

Therefore, it’s important to see your healthcare provider right away if you’re experiencing UTI symptoms—such as pain or burning when you urinate, fever, and an urge to urinate frequently.

Labs and Tests

If you’re seeing your healthcare provider for symptoms of a UTI, you’ll most likely have to provide a urine sample.

To make sure the sample is sterile, urine is often collected according to a process called “the clean catch method.”

• You’ll be given an antiseptic cleansing pad to clean your genital area before providing the urine sample.
• You will start your urine stream in the toilet and then urinate in the collection container, finishing your stream in the toilet.

Your collection container may have markings to indicate the amount of urine required for analysis.

Urine samples are used to perform the following types of diagnostic tests.

Urinalysis

Urinalysis (dip or microscopic) can be used to detect infections, kidney problems, and even help screen for diabetes. The test looks at the appearance, content, and concentration of urine.

The test can be done quickly using a dipstick. This is a quick way to check your urine and is often the go-to for home testing or quick office urine checks.

A microscopic urine test involves looking at the urine sample with a microscope. The test can help quantify the number of white blood cells, red blood cells, the presence of bacteria or crystals, and other markers. This test takes more time to get the results since it requires a laboratory professional to examine the sample.

Urine Culture

Also known as a “bacteria culture test,” a urine culture is frequently used as a follow-up to urinalysis. This can be done automatically in some labs if the initial urinalysis has abnormalities.

This test can identify and quantify specific bacteria, which helps in the selection of the most effective antibiotic to use in treatment.

A urine culture involves taking part of your urine sample and placing it in a special environment in the lab to promote cell growth. If bacteria are present, they will soon begin to multiply. There are also technology-based urine cultures.

Imaging

If your UTI symptoms are severe or don't improve with treatment, further testing can determine if you have other problems in your urinary tract. This can include imaging techniques, which provide pictures of the urinary tract.

Imaging tests used to diagnose urinary tract issues include ultrasounds, computerized tomography (CT) scans, and magnetic resonance imaging (MRI). These tests may also be used to identify urinary tract abnormalities that could be causing recurrent UTIs.

During the evaluation of recurrent UTIs, doctors sometimes perform an imaging test known as ​a cystoscopy to diagnose a reason for recurrent UTIs. The cystoscopy is not done during active UTI, but only when the UTI has resolved.

Cystoscopy

Performed by urologists (medical specialists who focus on the urinary tract), cystoscopy uses a long, thin, flexible or rigid instrument to look inside the urethra and bladder. This instrument is called a cystoscope and features an eyepiece (typically attached to a camera that projects to an LCD/video screen) at one end, a tube in the middle, and a tiny lens and light at the opposite end of the tube. In men, this test can also be used to look at the inside the prostate.

Preparing for the Procedure

Before your cystoscopy, your healthcare provider may ask you to drink plenty of liquid prior to the test. In some cases, you may need to temporarily discontinue certain medications (such as blood thinners).

What Will Happen

When used for evaluation of the urinary tract (including for workup of recurrent UTIs and or blood in urine), cystoscopy takes a few minutes. The test is typically done during an office visit or in an outpatient center or hospital. To prevent discomfort, your urologist will apply an anesthetic gel around the urethral opening (or inject a local anesthetic into the urethra).

• For females, cystoscopy is performed with the patient lying on their back with their knees up and spread apart.
• Male patients generally lie on their back during this test.

Once the anesthetic has taken effect, the urologist will gently insert the tip of the cystoscope into the urethra, then slowly advance it through the urethra and into the bladder.

When your urologist has finished examining your urethra and bladder, they may remove the saline from your bladder or ask you to empty your bladder by urinating.

After Care

After undergoing a cystoscopy, you may experience a mild burning feeling or discomfort in your bladder area or kidney area when urinating. Some patients also see small amounts of blood in their urine or feel the need to urinate more frequently or urgently. If these problems persist for more than 24 hours or a fever greater than 100.4F develops, make sure to consult your doctor.

Taking a warm bath or using over-the-counter pain relievers may help alleviate post-cystoscopy discomfort.

Differential Diagnosis

UTIs can trigger signs and symptoms similar to those associated with other issues affecting the urinary tract.

The following conditions are commonly considered during an evaluation for a possible UTI:

• Bacterial vaginosis
• Cancer of the bladder or urinary tract
• Interstitial cystitis
• Overactive bladder
• Pyelonephritis
• Sexually transmitted infection
• Urethral diverticulum
• Vaginitis in females
• Prostatitis in males

Your healthcare provider will be able to differentiate between these conditions based on your symptoms, physical examination, and diagnostic tests.