Summary
Read the full fact sheet- A urinary tract infection is caused by micro-organisms, usually a bacteria called Escherichia coli (E. coli).
- The urethra, bladder, vagina or kidneys can be affected.
- Even though urinary tract infections are very common, treatment with antibiotics may be needed, so seek advice from your doctor.
On this page
Urinary tract infections (UTIs) are very common – particularly in women, babies and older people. Around one in two women and one in 20 men will get a UTI in their lifetime.
The kidneys control the amount of water in the blood and filter out waste products to form urine. Each kidney has a tube called a ureter, which joins the kidney to the bladder. The urine leaves the kidneys through the ureters and enters the bladder. The bladder ‘signals’ the urge to urinate and urine leaves the body through a tube called the urethra. The urinary system is designed to minimise the risk of serious infection in the kidneys. It does this by preventing the urine from flowing back up into the kidneys from the bladder. Most urinary infections are confined to the bladder and, while causing symptoms, are not serious or life threatening.
Types of urinary tract infections (UTIs)
UTIs are caused by micro-organisms or germs, usually bacteria. The different types of UTI can include:
- cystitis – infection of the bladder. Cystitis is the most common lower urinary tract infection
- urethritis – infection of the urethra
- pyelonephritis – infection of the kidneys
- vaginitis – infection of the vagina.
Symptoms of UTIs
Common symptoms of UTIs include:
- wanting to urinate more often and urgently, if only a few drops
- burning pain or a ‘scalding’ sensation when urinating
- a feeling that the bladder is still full after urinating
- pain above the pubic bone
- cloudy, bloody or very smelly urine.
Symptoms of kidney infections
If infection reaches the kidneys, prompt medical attention is needed. In addition to the general symptoms of UTIs, a person with a kidney infection can also experience:
- chills
- fever
- loin (lower abdominal) pain
- pain in the back
- vomiting.
Causes of UTIs
Bacteria do not normally live in the urinary tract. When bacteria enter the urinary tract and multiply, they can cause a UTI.
There are many germs that can cause urine infections or cystitis. The most common germ causing urinary tract infections is found in your digestive system, Escherichia coli (E.coli). E.coli can easily spread to the urethra and stick to the lining of your urinary system.
Germs such as Mycoplasma and Chlamydia can cause urethritis in both men and women. These germs can be passed on during sexual intercourse so both partners need medical treatment to avoid re-infection.
Some people may be at higher risk of infections due to the urinary flow being blocked or when the urine flows back up from the bladder to the kidneys.
Risk factors for developing UTIs
Urinary tract infections in women
UTIs are common, particularly with increasing age. Women are more likely to get a UTI than men. Nearly 1 in 3 women will have a UTI needing treatment before the age of 24.
In women, the urethra is short and straight, making it easier for germs to travel into the bladder. For some women, UTIs relate to changes in their hormonal levels. Some are more likely to get an infection during certain times in their menstrual cycle, such as just before a period or during pregnancy.
In older women, the tissues of the urethra and bladder become thinner and drier with age as well as after menopause or a hysterectomy. This can be linked to increased UTIs.
During pregnancy, the drainage system from the kidney to the bladder widens so urine does not drain as quickly. This makes it easier to get a UTI. Sometimes germs can move from the bladder to the kidney causing a kidney infection. UTIs during pregnancy can result in increased blood pressure, so it is very important to have them treated as soon as possible.
Women are more at risk of repeated UTIs if they:
- use spermicide jelly or diaphragm for contraception
- have had a new sexual partner in the last year (an increase in sexual activity may trigger symptoms of a UTI in some women)
- had their first UTI at or before 15 years of age
- have a family history of repeated UTIs, particularly their mother
- suffer from constipation
Urinary tract infections in men
Men can get UTIs, particularly if they have trouble with urine flow. Older men who experience prostatitis (an inflammation of the prostate) are at a higher risk. If the bladder is not emptying properly, the build up of
urine makes it more difficult to cure the infection.
A small number of young men may get a UTI. In males, this is usually the result of a sexually transmitted disease.
Urinary tract infections and diabetes
People with diabetes are at increased risk of having UTIs as their urine may have a high glucose (sugar) content, which makes it easier for bacteria to multiply. Diabetes may also change the body’s immune (defence) system making it harder to fight a UTI. The risk of developing a UTI increases as diabetes progresses.
Urinary tract infections in older people
Chronic conditions, some medications, and problems with incontinence put older people at an increased risk for developing UTIs. People using bladder catheters are also more likely to develop a UTI.
Urinary tract infections in babies and young children
Babies and children are at risk of UTIs. These infections always need to be investigated as they may indicate a serious underlying condition, such as urinary reflux. Reflux is caused by a bladder valve problem allowing urine to flow back into the kidneys from the bladder. Reflux can cause the urine to stay inside the body increasing the risk of infection. It may lead to kidney scarring, which in turn leads to high blood pressure and sometimes kidney problems.
Prevention of UTIs
Although not always backed up by clinical research, some women have found some suggestions useful in reducing their risk of developing urinary tract infections, including:
- Drink plenty of water and other fluids to flush the urinary system.
- Treat vaginal infections such as thrush or trichomonas quickly.
- Avoid using spermicide-containing products, particularly with a diaphragm contraceptive device.
- Go to the toilet as soon as you feel the urge to urinate, rather than holding on.
- Wipe yourself from front to back (urethra to anus) after going to the toilet.
- Empty your bladder after sex.
- Avoid constipation.
Cranberries (usually as cranberry juice) have been used to prevent UTIs. Cranberries contain a substance that can prevent the E. coli bacteria from sticking to the urinary tract lining cells. However, recent research has shown that cranberry juice does not have a significant benefit in preventing UTIs, and most people are unable to continue drinking the juice on a long-term basis. Let your doctor know if you are having cranberry juice as it can alter the effectiveness of some antibiotics.
Treatment for UTIs
It is important to seek medical attention if you think you may have a UTI – particularly if you think you may have a bladder or kidney infection, both of which are very serious conditions. Early treatment of urinary infection can help to prevent infection spreading to the bladder or kidneys.
Your doctor will test your urine to check which micro-organism is present. Urinary tract infections usually respond quickly and well to antibiotics.
Where to get help
- Your GP (doctor)
- Community Pharmacist Pilot – receive some treatments at a local pharmacy without needing to see a doctor for a prescription in Victoria
- Kidney Health Australia Tel. 1800 454 363
- Urinary Tract Infections (UTIs), Kidney Health Australia
- Bladder infection (urinary tract infection – UTI) in adults , National Institute of Diabetes and Digestive and Kidney Diseases.
- Urinary tract infection in young children (UTIs), Parenting and Child Health, Government of South Australia.
- Urinary tract infection in children, The Sydney Children’s Hospital Network.
- Urinary tract infection (UTI), 2018, Kids Health Info, Royal Children’s Hospital, Melbourne.