Urinary Tract Infections (UTIs)


A urinary tract infection (also known as a bladder infection or acute cystitis) is the infection of a part or parts of the male or female urinary tract. The urinary tract is made up of the kidneys, ureters, bladder, and urethra. A urinary tract infection (or UTI) is not technically a sexually transmitted infection, however, sexual activity is a common cause of UTIs for sexually active adults.1 When the infection affects the lower urinary tract, the condition is known as a simple cystitis (a bladder infection), and when it affects the upper urinary tract, it is known as pyelonephritis (a kidney infection). The most common causal agent of UTIs is the bacterium Escherichia coli, commonly found in the lower intestine of warm-blooded organisms.1

(Image Caption: E. coli, found in the intestines of most mammals, is the bacterium responsible for causing most UTIs)

Females are at a greater risk of developing a UTI than are males, with about half of all females experiencing at least one infection at some point in their lives.1 Urinary tract infections can vary widely in their difficulty of treatment: some cases require only a short course of antibiotics, while others necessitate more invasive methods of treatment, such as dialysis, an artificial replacement for lost kidney function.3


Signs or symptoms of a urinary tract infection may not always be noticeable, but if symptoms are present, they will typically manifest in one of the following ways:

  • A strong, persistent urge to urinate

  • A burning sensation when urinating

  • Frequent, small amounts of urine

  • Urine that appears cloudy

  • Urine that appears red, bright pink, or cola-colored — a sign of blood in the urine

  • Strong-smelling urine

  • Pelvic pain (in women)

  • Rectal pain (in men)2

UTI symptoms may also vary depending on which part of the urinary tract is infected.2 If only the urethra (the tube that leads from the bladder and transports and discharges urine outside the body) is infected, burning with urination should be the only symptom noticed. Infection of the urethra is known as urethritis.

If the infection is in the bladder, the infection is called a cystitis and may include the following symptoms:

  • Pelvic pressure

  • Lower abdominal discomfort

  • Frequent, painful urination

  • Blood or pus in the urine2

Most UTIs involve only the bladder and urethra, known as the lower urinary system. However, serious infections may spread to the upper urinary system (the kidneys and ureters), resulting in an infection known as acute pyelonephritis. Acute pyelonephritis is a very serious medical condition, in which the infection has opportunity to enter the bloodstream (sepsis) and spread to other healthy tissues in the body.2

If such blood infection occurs, one's risk of mortality increases significantly, particularly among children and the elderly. The presentation of acute pyelonephritis is notably distinct from that of the less severe lower tract infections, and typically include the following symptoms:

  • Upper back and side (flank) pain

  • High fever

  • Shaking and chills

  • Nausea

  • Vomiting2

  • Frequent urge to urinate

  • Generalized malaise

  • Abdominal pain

Signs and symptoms of a urinary tract infection may be especially difficult to observe in children or the elderly. In young children, the only symptom of a urinary tract infection may be a fever. Infants may also feed poorly, vomit, sleep excessively, or show signs of jaundice (yellowing of the skin and eyes). In older children, a loss of bladder control can occur. UTI symptoms in the elderly can be even more vague, sometimes presenting as incontinence, a change in mental status, or general fatigue. Diagnosis of UTIs in the elderly can be further complicated by preexisting or comorbid incontinence or dementia.1

Causes and Risk Factors

Urinary tract infections normally occur when bacteria enter the urinary tract through the urethra and begin to multiply in the bladder, sometimes spreading to other nearby tissues. Although the human urinary system is designed to keep out such microscopic invaders, these defenses are not perfect and sometimes fail. When this occurs, bacteria may seize this opportunity to secure a habitat and grow into a full-blown infection in the urinary tract. Infection may also occur via the blood or lymph. The common intestinal bacterium, E. coli, causes of 80-85% of urinary tract infections. After gaining entry to the bladder, E. coli are able to attach to the bladder wall and form a biofilm that resists the body's immune response. However, other bacteria, such as Staphylococcus saprophyticus (responsible for 5-15% of cases) or viruses and fungi, can also cause UTIs. Risk factors for contracting a UTI include the following circumstances:2

  • Being female. UTIs are more common in females than males, and many females experience more than one infection throughout their life. This is likely due to the fact that biological females have a shorter urethra than do males, which effectively reduces the distance that bacteria must travel to reach a female's bladder.

  • Being sexually active. Sexually active individuals tend to have more UTIs than do those who are not sexually active.

  • Using certain types of birth control. Research has shown that females who use diaphragms as a method of birth control may be at higher risk for contracting a UTI, as well as females who use spermicidal agents.2

  • Completing menopause. After menopause, UTIs may become more common due to a lack of estrogen, which causes changes in the urinary tract that make it more vulnerable to infection.

  • Having urinary tract abnormalities. Infants born with urinary tract abnormalities that do not allow urine to normally exit the body or cause urine to back up in the urethra have an increased risk of contracting a UTI.

  • Having blockages in the urinary tract. Kidney stones or an enlarged prostate can trap urine in the bladder and increase the risk of contracting a UTI.

  • Having a suppressed immune system. Diabetes and other diseases that impair the immune system can increase the risk of contracting a UTI.

  • Using a catheter to urinate. People who are unable to urinate on their own and use a tube (catheter) to urinate have an increased risk of UTIs. This may include people who are hospitalized, people with neurological problems that make it difficult to control their ability to urinate, and people who are paralyzed.

A predisposition for bladder infections may also run in families.

(Image caption: Females using a diaphragm as their primary method of birth control are at greater risk of contracting UTIs.)


A physician may utilize a variety of tests and procedures to diagnose a UTI. These tests may include the following:

  • Urine analysis. Your doctor may ask for a urine sample for lab analysis to look for white blood cells, red blood cells, or bacteria. To avoid potential contamination of the sample, you may be instructed to wipe your genital area with an antiseptic pad and collect the urine midstream.

  • Urine culture. Lab analysis of the urine is sometimes followed by a urine culture: a test that uses your urine sample to grow bacteria in a lab. This test tells your doctor which bacteria are causing your infection and which medications will be most effective for treatment.

  • Creation of images of your urinary tract. If your doctor suspects that an abnormality in your urinary tract causes frequent infections, you may be asked to complete an ultrasound or a computerized tomography (CT) scan to create images of your urinary tract. In certain situations, your doctor may also use a contrast dye to highlight certain structures in your urinary tract. Another test, called an intravenous pyelogram (IVP), uses X-rays with contrast dye to create images. Historically, doctors used this test for urinary tract imaging, but it is being replaced more often by ultrasound or CT scan.

  • Cystoscopy. If you have recurrent UTIs, your doctor may perform a cystoscopy, using a long, thin tube with a lens (cystoscope) to see inside of your urethra and bladder. The cystoscope is inserted into your urethra and passed through to your bladder.

(Image caption: Diagnosis of a UTI typically begins with a urine sample.)

While UTI symptoms are already sometimes vague, a diagnostic physician must not only diagnosis the infection but also differentiate this vague condition from a huge variety of other similarly vague conditions. Individuals with an inflamed vagina (a condition easily confused as a symptom of a UTI) may actually be experiencing a yeast infection. Because yeast is a fungus rather a bacterium, the methods of treating this kind of infection typically differ from those used for UTIs. Inflammation of the prostate may also be considered in the physician's differential diagnosis.

A rare and especially complicated scenario arises when a patient experiences multiple episodes of UTI symptoms, despite his or her urine cultures producing negative results for infection. When it becomes clear that the patient's symptoms are unimproved by antibiotics, and other diagnoses are unrealistic, he or she may be diagnosed with a terminal condition known as interstitial cystitis.5 Interstitial cystitis, also known as bladder-pain syndrome or IC, is characterized by a recurring discomfort or pain in the bladder and the surrounding pelvic region. The symptoms vary from case to case and even in the same individual over time. Individuals with IC may experience mild discomfort, pressure, tenderness, or intense pain in the bladder and pelvic area. Symptoms may include an urgent need to urinate, a frequent need to urinate, or a combination of these symptoms. Pain may change in intensity as the bladder fills with urine or as it empties, and individuals with IC may sometimes experience pain during vaginal intercourse. Interstitial cystitis is incurable and its cause is unknown. Symptoms of interstitial cystitis have been reported to persist even following complete removal of the bladder, resulting in what can be described as a “phantom bladder pain.”5


Most urinary tract infections can be treated successfully without complication. Bladder infection (cystitis) symptoms typically dissipate within a few days after treatment begins. Kidney infections (acute pyelonephritis) are generally longer lasting, sometimes taking one week or longer for symptoms to disappear once treatment has begun.2


When given proper and prompt treatment, lower urinary tract infections rarely lead to other health complications. However, if left untreated, such infections could progress to trigger a number of potentially life-threatening conditions. Typically, an untreated lower urinary tract infection will eventually spread from the bladder to one or both kidneys, possibly causing permanent irreversible damage to proper kidney function and increasing one's risk of complete kidney failure. There is also a small chance that the infection may enter the bloodstream from the kidneys, resulting in a possibly fatal whole-body inflammation known as sepsis. Recurrent infections are a common complication, especially in women who have experienced three or more UTIs.4 It is due to these serious complications that individuals observing early UTI-like symptoms are highly encouraged to seek immediate medical help.1


The standard treatment for urinary tract infections is the prescription of oral antibiotics taken over a typical course of seven to ten days. Drugs commonly prescribed for uncomplicated UTIs include the following:

  • Sulfamethoxazole-trimethoprim (Bactrim, Septra)

  • Amoxicillin (Amoxil, Augmentin)

  • Nitrofurantoin (Furadantin, Macrodantin)

  • Ampicillin (Principen)

  • Ciprofloxacin (Cipro)

  • Levofloxacin (Levaquin)2

A physician may also prescribe a pain medication to numb the bladder and urethra in order to relieve burning during urination. Such urinary-tract analgesics tend to cause urine to turn red or orange in color.2

(Image caption: Oral antibiotics are the most common effective treatment for UTIs)

For patients who experience frequent recurring infections, a physician may make specific treatment recommendations, such as the following

  • A longer course of antibiotic treatment

  • A home urine test to check for infection

  • A single dose of an antibiotic to be taken after sexual intercourse

  • A vaginal estrogen therapy for postmenopausal women2

Patients with frequent UTIs may find relief in certain lifestyle changes or other complementary therapies. The following is a list of nutritional and supplemental changes patients experiencing frequent UTIs might add to their lifestyle. These may not be right for every patient and it is recommended to discuss all alternative therapies with your physician. Following these nutritional tips may help reduce symptoms:6

  • Drink a lot of fluids, such as herbal teas and water. Avoid sweetened fruit juices and other sweetened drinks.

  • Eat cranberries and blueberries, which both contain substances that inhibit the binding of bacteria to bladder tissue. Drinking unsweetened cranberry juice regularly helps lower to the risk of UTIs.

  • Eliminate potential food allergens, including dairy, wheat (gluten), corn, preservatives, and food additives. Your healthcare provider may want to test for food sensitivities. If you are susceptible to UTIs, drinking cranberry juice or taking cranberry pills may help prevent recurrence.

  • Eat antioxidant-rich foods, including fruits (such as blueberries, cherries, and tomatoes) and vegetables (such as squash and bell peppers).

  • Eat more high-fiber foods, including beans, oats, root vegetables (such as potatoes and yams), and psyllium seeds.

  • Avoid refined foods, such as white breads, pastas, and especially sugar.

  • Eat fewer red meats for protein. Eat lean meats (such as poultry or trimmed beef and pork), coldwater fish, tofu (if no allergy to soy is present), and/or beans for protein.

  • Use healthy cooking oils, such as olive oil or coconut oil. Avoid harshly processed oil and fat products such as canola oil or margarine.

  • Reduce or eliminate trans fatty acids, which can found in commercially baked goods (cookies, crackers, cakes, French fries, onion rings, donuts, processed foods, and margarine).

  • Avoid coffee and other stimulants, alcohol, or tobacco.

  • Drink more water. Six to eight glasses daily should help support healthy bodily function.

  • Exercise at least thirty minutes daily, five days per week.

(Image caption: Eating antioxidant-rich foods like berries may help reduce UTI symptoms and frequency.)

Individuals may also choose to address nutritional deficiencies that are potentially exacerbating their symptoms and frequency. Such deficiencies may be remedied with the following nutritional supplements:6

  • A daily multivitamin containing the antioxidant vitamins A, C, E, the B-complex vitamins and trace minerals, such as magnesium, calcium, zinc, and selenium.

  • Vitamin C, 500–1,000 mg once or twice daily, as an antioxidant and for immune support.

  • Omega-3 fatty acids, such as fish oil, one or two capsules or one tablespoonful of oil (taken once or twice daily), to help decrease inflammation and promote general health. Coldwater fish, such as salmon or halibut, are excellent sources of omega-3 fatty acids. Fish oil supplements can increase the effects of certain blood-thinning medications.

  • IP-6 (Inositol hexophosphonate), 1–8 grams daily on an empty stomach, for kidney health. There is some concern that IP-6 may interfere with blood clotting. Patients should exercise caution if they have a clotting disorder or take blood-thinning medications.

  • L-glutamine, 500–1,000 mg three times per day, for support of gastrointestinal health and immunity. Glutamine may increase the risk of mania or seizures in susceptible people and may interfere with some anticonvulsant medications.

  • Probiotic supplement (containing Lactobacillus acidophilus), 5–10 billion CFUs (colony forming units) a day, for maintenance of gastrointestinal and immune health. There is strong scientific evidence to support the use of probiotics for urological conditions. Refrigerate probiotic supplements for best results.

  • Grapefruit seed extract (Citrus paradisi), 100 mg capsule or 5–10 drops (in favorite beverage) 3 times daily, for antibacterial, antifungal, and antiviral activity. Grapefruit may interact with a wide variety of medications, so individuals considering this supplement should consult their physician before adding it to their diet.6

(Image caption: Increasing your consumption of vitamin C may maintain healthy immune system function and prevent future UTIs.)


Urinary tract infections are caused by germs, typically E. coli entering the urethra and spreading to other parts of the urinary system. Prevention of this occurrence is therefore key to reducing the frequency of UTI contractions.

The first step in preventing future infections is to take your prescribed medication. Typically, a patient will be prescribed an oral antibiotic, sometimes accompanied with a urinary tract pain-relief medicine known as Phenazopyridine hydrochloride (Pyridium).4 Dutiful adherence to your physician's instruction is the quickest route to recovery and prevention. Lifestyle changes in hygiene may also help to prevent some UTIs:4

  • Use sanitary pads instead of tampons. Some doctors believe tampons increase the likelihood of infection. Sanitary pads should be changed with each bathroom visit.

  • Do not douche or use feminine-hygiene sprays or powders. As a general rule, do not use any product containing perfumes in the genital area.

  • Take showers instead of baths. Avoid bath oils.

  • Keep your genital area clean. Clean your genital and anal areas regularly, especially before and after sexual activity.

  • Wipe from the front to the back when using the bathroom, especially for females. Wiping back to front greatly increasing the your risk of spreading E. coli from your anus to your urethra.

  • Urinate before and after sex to clear the urethra of any potential pathogens.

  • Avoid tight-fitting pants. These hot, moist regions of the body are prime locations for the spread bacteria.

The following diet changes have also been shown to prevent UTIs:4

  • Drink plenty of healthy fluids (two or four quarts every day).

  • Drink cranberry juice, but not if you have a personal or genetic history of kidney stones.

  • Do not drink bladder-irritating fluids like alcohol and caffeinated beverages.4

After a patient has completed his or her course of antibiotics, it is crucial that he or she visits a healthcare provider for a followup appointment to ensure that the infection is gone; otherwise, symptoms may persist or return.1



1) "Uncomplicated Urinary Tract Infection in Adults Including Uncomplicated Pyelonephritis."Urology Clinics of North America 35.1 (2009): 1-12. Web

2) "Urinary Tract Infection (UTI)." Mayo Clinic. Mayo Foundation for Medical Education and Research, n.d. Web. 13 Mar. 2014. <http://www.mayoclinic.org/diseases-conditions/urinary-tract-infection/ba....

3) "Dialysis: MedlinePlus."U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 12 Mar. 2014. <http://www.nlm.nih.gov/medlineplus/dialysis.html>.

4) "Urinary Tract Infection - Adults: MedlinePlus Medical Encyclopedia."U.S National Library of Medicine. U.S. National Library of Medicine, n.d. Web. 13 Mar. 2014. <http://www.nlm.nih.gov/medlineplus/ency/article/000521.htm>.

5) "Interstitial Cystitis."Mayo Clinic. Mayo Foundation for Medical Education and Research, n.d. Web. 13 Mar. 2014. <http://www.mayoclinic.org/diseases-conditions/interstitial-cystitis/basi....

6) "Urinary Tract Infection in Women."University of Maryland Medical Center. N.p., n.d. Web. 13 Mar. 2014. <https://umm.edu/health/medical/altmed/condition/urinary-tract-infection-....


Last updated 14 May 2014.