Understanding UTI Testing: The Significance of Negative Results
If you've ever had symptoms suggesting a urinary tract infection (UTI), you know the drill: a quick urine dipstick test at the doctor's office, followed by a prescription for antibiotics. But what if I told you that this common approach might not always be the best route?
Or what about going to the clinic with painful UTI symptoms, your sample is sent to the lab, just to wait three days to then be told your urine culture test is negative or contaminated. Leaving you frustrated and asking google, “what antibiotic is used for urinary tract infection?”
Not all UTI tests are created equal, so we decided to discussed the world of UTI testing with Dr. Fenwa Milhouse from Down There Urology. In this blog, we review specifically what it means when you get a negative urine dipstick test or urine culture as well as what to expect out of a UTI PCR test. And — how a negative test could be a good thing, check it out.
Urine Dipstick Test: Preliminary Look
How It Works: provide a urine sample, and a special strip (the dipstick) with chemical pads is dipped into it. These pads change color based on the presence of certain substances in the urine that can indicate inflammation or signs of infection. Here is an example dipstick test.
Timing for Results: Results are available within minutes.
Accuracy: They aren't foolproof. In fact data shows up to 70% of the time they are inaccurate, giving false positives or negatives. For example, certain medications or foods can affect the results.
Limitations: A urine dipstick test alone can't confirm a UTI. It's more of a screening tool that suggests whether further testing (like culture or PCR) is needed. It won’t tell you what type of bacteria is causing the infection, if any.
Culture Testing: Traditional Approach
How It Works: A urine sample is collected in-office and at the lab placed on a petri dish. The dish is then incubated, allowing any bacteria present to grow over a period of time.
Timing for Results: This is a bit of a waiting game. It usually takes about 3-5 days for bacteria to grow enough to be identified.
Accuracy: Culture tests are quite reliable in detecting the common bacteria that cause UTIs. However, they might not pick up on less common bacteria or run into issues if multiple culprits are present.
Limitations: The main drawback is the time it takes to get results. Also, if the urine isn’t handled properly, if there is a biofilm or if there’s a delay in getting it to the lab, it can affect the accuracy.
PCR Testing: Modern Method
How It Works: PCR (Polymerase Chain Reaction) testing is like a high-tech detective. It amplifies the DNA present in your urine sample to look specifically for bacterial DNA, even finding multiple culprits behind UTIs.
Timing for Results: PCR is speedy! You can expect results within hours or, at most, a day.
Accuracy: PCR tests are highly accurate and sensitive. They can detect even a small amount of bacterial DNA, making them excellent for early detection or if there are multiple bacteria (Read about biofilms) causing a urinary infection.
Limitations: Despite its precision, PCR can sometimes be too sensitive, some tests detect a wide array of bacteria and yeast. While it can be nice to see all the good and bad bacteria present, some bacteria found may not necessarily be causing the urinary tract infection symptoms. This is why it is important to know the bacteria or yeast a test may be able to identify.
Urinary Tract Infection Testing
MyUTI is an at home PCR test for UTIs - Learn More
What Does a Negative Result Tell Us?
When seeking treatment for UTIs, it is essential to understand what testing is being performed and what the results really tell you so you can seek alternative UTI testing options if appropriate.
Dr. Milhouse explains, “As clinicians, we know that no testing method is ever 100% accurate. What is important is to understand what the results can or cannot tell us.”
Urine Dipstick Test:
A negative test doesn't really tell you anything, especially if the person is experiencing symptoms and a trace of blood in urine dipstick tests does not guarantee that the issue is a UTI.
Culture Test:
A Negative test doesn't necessarily mean there wasn't any bacteria growth. What it can mean is that not enough of the common bacteria e.coli grew in a specified time period.
No growth? It likely means the usual UTI bacterial culprits aren't present.
Mixed Flora? This means that more than two bacterial species grew and the lab will assume it's contaminated.
UTI PCR Test:
A Negative test report suggests there was not enough or none of the specific bacterial DNA found in the sample, and strong evidence against an infection.
Receiving a negative test result can be frustrating, especially if you continue to have UTI symptoms. A key thing to remember is opening a dialogue with a trusted healthcare provider, which may include discussing using an at home PCR test like the at home UTI test by MyUTI.
Get Answers, Find Relief.
PCR Testing conveniently from home. Understand the root cause of repeat UTI symptoms.
Navigating Your Health Care With a Negative Test Result
This is where things get interesting. As Dr. Milhouse explains, “a negative result doesn't mean your symptoms are imaginary; it just means we need to think outside the box. Vaginal burning can seem like a UTI but may just be GSM (genitourinary syndrome of menopause) and the frequent urge to run to the bathroom may be an underlying issue like overactive bladder.”
With repeat infections and negative urine dipstick or culture results, working with a specialist can help to uncover if there may be an alternative testing, procedures or diagnosis to explore and the need for tailored treatment strategies.
Navigating Perimenopause & Menopause:
Talk to your doctor about vaginal estrogen. Hormonal changes can cause changes in the vaginal pH and the vulvar tissue, causing irritation that mimic or exacerbate UTI-like symptoms.
Individuals in Their 20s and 30s:
Consider lifestyle factors. Could dietary changes, drinking more water, or taking supplements help? Does the fluctuation of your hormones or period make you more susceptible to a UTI? Perhaps sexual activity is a trigger for your infections and are there steps that you can take to reduce risk, like found in this article.
In both cases, discuss with your healthcare provider as hormonal and lifestyle triggers can impact individuals of all ages and genders.
The Power of Conversation
A negative UTI test result, be it culture or PCR, is not the end but a crucial step in your treatment and care journey. It should open up the conversation for alternative diagnoses and treatment strategies, especially tailored to your age and symptoms.
“There are many conditions and infections that can mimic a UTI, so there really is power in having confirmed negative tests by culture or PCR. When a patient has a negative PCR test, and continues to be symptomatic, I know that we can begin to look at alternative treatment modalities to help them find answers & relief,” shares Dr. Fenwa Milhouse.
Engaging in Informed Discussions with Your Doctor
There are a number of steps you can take to have a productive visit with a clinician is discussing your repeat urinary tract symptoms.
Being specific about your symptoms can make a world of difference. Instead of saying, "I think I have a UTI," describe exactly what you're feeling and what does that mean to you? Does it mean constant urge? Burning with urination? Abdominal pain? Back pain? This helps in considering all possible causes and treatments beyond antibiotics.
Knowing the types of tests you have had performed and understanding how they work as well as the limitations with the results will help you feel more empowered and lead to more meaningful conversations with your healthcare provider.
To support your conversation with a healthcare provider, download this free discussion guide!
As someone educated and informed, use this opportunity to discuss a broader range of options with your doctor, ensuring a more personalized and effective approach to your healthcare.
