What is urinary tract infection?
A urinary tract infection (UTI) occurs when microorganisms invade the urinary tract and begin to multiply. The urinary tract is a system responsible for the production, storage, and elimination of urine in the body. It comprises four components:
- Kidneys: Organs that produce urine.
- Ureters: Tubes that transport urine from the kidneys to the bladder.
- Bladder: A reservoir for storing urine.
- Urethra: A tube through which urine is released from the bladder during urination.
While an infection can develop in any part of the urinary tract, it is most frequently observed in the bladder.
What causes urinary tract infection?
The majority of urinary tract infections (UTIs) are caused by bacteria that enter the urinary tract. The most common bacteria responsible for UTIs is E. coli, which is normally present in the intestines and aids in digestion. UTIs occur when bacteria from the intestinal tract find a pathway to enter and multiply in the urinary tract.
UTIs are more prevalent in individuals with vaginas. This is because their urethra, the tube connecting the bladder to the outside, is shorter, allowing bacteria a shorter distance to travel to reach the urinary tract.
In individuals with penises, the urethra is longer, making UTIs uncommon between the ages of 15 and 50.
Sexual activity can facilitate the movement of bacteria from the intestinal tract to the urinary tract, increasing the risk of UTIs in sexually active individuals.
Urinary catheters, which are medical devices used for bladder emptying, can also contribute to UTIs. If UTI symptoms develop after surgery or catheter use, it may indicate that the catheter introduced bacteria into the bladder, providing a conducive environment for their growth.
Occasionally, UTIs can result from bacteria entering the kidneys through the bloodstream. This is more likely to occur in individuals with underlying medical conditions, such as a weakened immune system, endocarditis (infection in the heart), or sepsis (severe infection in the body).
What are the symptoms of urinary tract infection?
The most commonly experienced symptoms of UTI include:
- Discomfort or a burning sensation during urination
- Feeling a strong urge to urinate
- Frequent need to urinate
- Urine that appears cloudy, pink, or has a slight presence of blood
- Pain in the lower abdominal area, where the bladder is located
The upper urinary tract, consisting of the kidneys and ureters, and the lower urinary tract, comprising the bladder and urethra, are the two main parts of the urinary system. Infections affecting the upper urinary tract, known as pyelonephritis, are more severe than those affecting the lower tract. Pyelonephritis can cause symptoms like high fever, vomiting, and pain in the back or sides.
How is urinary tract infection diagnosed?
To diagnose a UTI, medical professionals typically use one of three different tests to examine the urine for signs of infection.
Urine dipstick test
The urine dipstick test is the most commonly used method to detect a UTI. This test is quick and can be conducted in the healthcare provider’s office. It checks for indicators of inflammation in the urine, such as leukocyte esterase (a product of white blood cells), nitrites (produced by certain bacteria), and blood. However, it’s important to note that the urine dipstick test may not always be the most reliable option since factors like menstrual blood or sexually transmitted infections (STIs) can sometimes affect the results.
A urinalysis typically takes about one day to complete. During this test, the urine is examined for signs of infection and analyzed under a microscope. It can identify the presence of red and white blood cells, bacteria, and yeast. While a urinalysis can provide more specific information than a dipstick test, it is not as rapid or accurate in detecting UTIs.
A urine culture is the most accurate test for diagnosing a UTI. It allows laboratory professionals to study the bacteria causing the infection and determine the most effective antibiotics for treatment. However, a urine culture usually takes several days to produce results. Waiting for the culture results before starting treatment with antibiotics would result in additional discomfort and the potential for a mild infection to worsen. Therefore, in most cases, a urine culture is not performed for otherwise healthy individuals with clear UTI symptoms.
What medication can be used for urinary tract infection?
For the majority of adults with a UTI in the lower urinary tract, a 3- to 5-day course of antibiotics is usually sufficient. However, individuals with more complex UTIs, such as those with underlying medical conditions, young children, or individuals with kidney infections (pyelonephritis), often require a longer duration of treatment.
The selection of antibiotics for UTI treatment depends on various factors. Your healthcare provider will consider:
- The bacteria responsible for the infection
- The level of antibiotic resistance in your local area
- The strengths and weaknesses of various medications
- Your personal medical background and history
Commonly prescribed antibiotics for treating UTIs in adults:
- Nitrofurantoin (Furadantin, Macrobid, Macrodantin)
- Trimethoprim/sulfamethoxazole (Bactrim, Sulfatrim)
- Fosfomycin (Monurol)
- Ciprofloxacin (Cipro)
- Levofloxacin (Levaquin)
- Amoxicillin/clavulanate (Augmentin)
A UTI is an infection that happens when microorganisms invade the urinary tract system, which includes the kidneys, ureters, bladder, and urethra. Most often, the bladder is the site of infection.
The most common cause of UTIs is bacteria, especially E. coli from the intestines. UTIs are more prevalent in individuals with vaginas due to a shorter urethra. Sexual activity, use of urinary catheters, and certain underlying medical conditions can increase the risk.
This is because they have a longer urethra, making it more difficult for bacteria to travel and infect the urinary tract.
Common symptoms include a burning sensation during urination, frequent urge to urinate, cloudy or pinkish urine, and lower abdominal pain. Infections of the upper urinary tract can result in high fever, vomiting, and back or side pain.
UTIs can be diagnosed using a urine dipstick test, urinalysis, or urine culture. The urine culture is the most accurate but may take several days to produce results.
Yes, factors like menstrual blood or STIs can sometimes interfere with the results of a urine dipstick test.
A urinalysis typically takes about one day to complete.
UTIs are commonly treated with antibiotics. The choice of antibiotic and the duration of treatment depend on the bacteria causing the infection, local antibiotic resistance patterns, the specific medication’s pros and cons, and the patient’s medical history.
Yes, common antibiotics for UTIs include Nitrofurantoin, Trimethoprim/sulfamethoxazole, Fosfomycin, Ciprofloxacin, Levofloxacin, and Amoxicillin/clavulanate.
Individuals with more complex UTIs, such as those with underlying medical conditions, young children, or those with kidney infections, may require a more extended treatment course.
Yes, occasionally, bacteria can enter the kidneys from the bloodstream, leading to UTIs. This is more common in people with weakened immune systems or conditions like endocarditis or sepsis.
Sexual activity can facilitate the movement of bacteria from the intestinal tract to the urinary tract, increasing the risk of UTIs.