A urine culture is a test that can detect bacteria in your urine. This test can find and identify the germs that cause a urinary tract infection (UTI). Bacteria, which typically cause UTIs, can enter the urinary tract through the urethra. In the environment of your urinary tract, these bacteria can grow rapidly and develop into an infection.
Learn more: What do you want to know about urinary system infection? »
Urine cultures can identify the microorganisms, typically bacteria, which cause a UTI. UTIs are more common in females than males. This is because a woman’s urethra is shorter and much closer to the anus. Therefore, it’s much easier for bacteria from the intestines to find their way into the urinary tract. Bacteria ascend the urethra into the bladder, ureters, and kidneys, where they can develop into an infection.
The most common symptoms of a UTI are:
- pain and discomfort, typically in the lower back and abdominal area
- pain when urinating
- feeling an urge to urinate frequently
- difficulty in your urine stream
If you have a UTI, your urine might appear cloudy or even turn a pinkish or coral shade if there is blood present. Even though you may feel a constant urge to urinate, you may have difficulty getting more than a small amount of urine to exit your bladder. In cases where the infection is becoming more serious, you may experience shaking, chills, or vomiting.
The urine for a urine culture can be collected in several different ways. The most common method for collecting urine is the midstream clean-catch method. For this, you collect your urine in a cup as you urinate.
- Before you begin this process, a healthcare provider will ask you to wash your hands and then wash your genitalia with a cleanser.
- You will begin urinating into a sterile cup provided by your doctor.
- The cup is then given to your healthcare provider, who sends it to a lab for analysis.
Urinary collection bag
A urine sample can also be collected with a urinary collection bag. This method is used most commonly with children and infants. For this procedure, a plastic bag is attached with adhesive to a girl’s labia or a boy’s penis. When the child begins urinating, the bag catches the urine, which can then be sent to a lab for analysis.
In some cases, a healthcare provider needs to collect a urine sample with a catheter. To do this, they insert a thin rubber tube through the urethra and into the bladder. Once the catheter is in place, the healthcare provider is able to collect a sample. If you already have a urinary catheter in place, a healthcare provider can collect a sample by clamping the drainage end of your catheter before it reaches the drainage bag. Once urine passes into the clamped tube, your healthcare provider uses a syringe to remove a urine sample. Urine samples should not be taken directly from a catheter collection bag because urine that has been out of the body too long may begin to grow bacteria and will not make for a good sample.
In rare cases, your doctor may need to remove a urine sample from your bladder with a needle. This procedure, called a suprapubic aspiration, is used if previous attempts at collecting an uncontaminated sample have been unsuccessful.
If you are pregnant, your obstetrician may have you do a urine culture at several points during your prenatal care as a precautionary measure. If you have developed a UTI during your pregnancy, it’s essential to catch it and treat it. UTIs are common in pregnancy and can, at times, go unnoticed. Untreated UTIs can lead to premature labor or poor labor outcomes.
Collecting a urine sample is not painful, unless you are experiencing pain while urinating because of an existing UTI. There are no risks associated with preparing for or performing a urine collection.
If your doctor requests a urine sample obtained with a catheter, you may feel some pressure and discomfort as the thin tube is inserted through your urethra. These tubes are lubricated to reduce pain and make the procedure much easier. Rarely, a catheter can create a hole in your urethra or bladder. Your doctor will discuss with you ways to reduce pain while performing the procedure.
Before you begin your test, tell your doctor if you’re taking or have recently taken any medications or over-the-counter vitamins, medicines, and supplements. These may interfere with the lab’s results. Aside from washing your hands and your genitalia before the clean-catch collection, you don’t need to prepare for a urine culture. If you know you will need to conduct a urine collection during an appointment with your doctor, avoid urinating until you’re able to collect a sample. If you have any questions or concerns about the test, the risks, or the results, speak with your doctor.
For a urine culture, the urine is given several days to allow the bacteria, if present, to grow. The sample is then examined under a microscope. If your urine shows signs of bacteria or other organisms, you will receive a positive result. If few bacteria or organisms appear, you will receive a negative test result. The person conducting the urine culture will also be able to determine which organisms are causing the infection, either by sight or through an additional test.
Results of a urine culture are typically ready in two to three days. If your result comes back positive, your doctor may prescribe an antibiotic to help eliminate the harmful bacteria.
Sometimes there may be more than one kind of bacteria, or a very small bacterial presence, in your sample. In these cases, there may be a delay in getting your result. You may also need to take the test again.
Most UTIs are caused by E. coli, which are often found in your stool. Staphylococcus and Proteus are two other varieties of bacteria likely to cause UTIs. Sometimes a urinary tract infection is caused by Candida, which is yeast that can overgrow. Occasionally, a UTI will be triggered by a sexually transmitted infection (STI).
A UTI is most often treated with a round of antibiotics. The type of antibiotic prescribed can vary according to what kind of bacteria you are fighting off, your medical history, and whether or not your UTI has been recurrent. If you continue to have frequent UTIs, you may need to be tested for your susceptibility to them.
You can begin to treat a UTI at home by drinking plenty of water and urinating frequently. Every opportunity you have to try to flush out some of the bacteria will help your body to recover more quickly. Vitamin C supplements will help boost your immune system. Think of them as ammunition for your white blood cells as they fight the infection.
The herb goldenseal (also called berberine) is sometimes recommended for supplemental treatment of UTIs. At one time, drinking unsweetened cranberry juice was believed to flush out bad bacteria from the urinary tract. However, in recent years, that claim has become hard to prove.
If you suspect you have a UTI, it’s probably because you’re having uncomfortable symptoms. Proper treatment of the infection should resolve most of your discomfort within 48 hours. Wearing loose-fitting, cotton underwear and washing frequently can help keep the infection from coming back.
A UTI is not generally cause for alarm. But if you think you have one, seek medical treatment. It’s possible for it to escalate and cause a kidney infection that affects your entire body.
Pain in the low back or side below your ribs and feeling shaky and weak are symptoms you should not ignore. If you notice these symptoms, contact your doctor.