Most urinary tract infections (UTIs) are a simple illness, irritating but it does not make you that unwell – and respond well to antibiotics. But they can, occasionally, be serious or even life-threatening – and require hospital admission.
1. What is a UTI?
A urinary tract infection (UTI) is an infection in any part of the urinary tract (system). The system includes the kidneys, ureters, bladder and urethra (and prostate in a man). The main function of the urinary system is make urine; which is the system for removing water and waste from the body. The kidneys and urinary tract are the body’s dustmen.
2. What are the different types of UTI?
There are different types of UTI, and the symptoms are different. The doctors name for the type of infection, depends on which part of the urinary tract is affected, e.g.
- Kidney = pyelonephritis – causing pain in the back/side of tummy
- Bladder = cystitis – lower tummy pain at the front, burning when you wee, and weeing more frequently
- Urethra = urethritis – burning when you wee, and weeing more frequently
- Prostate = prostatitis (men only) – pain in genital area.
Urinary tract
Most infections involve the lower urinary tract – the bladder (cystitis) and urethra (urethritis). Cystitis is the commonest. For such infections, in adult women of child bearing age, there is not (usually) an underlying cause.
3. Who gets UTIs?
Women are at much greater risk of developing UTI than men. They usually start in women when they become sexually active. Many women will have one or more mild UTI a year.
Pregnant women are especially prone. They can become quite unwell, so should be treated rapidly; with a repeat urine sample (MSU, see below) sent after a course of treatment, to make sure it has gone.
Men and children rarely get UTIs. If they do, doctors should look for an underlying cause (see investigations below).
People with long term urinary catheters (into the bladder) often have a UTI. If the patient is not unwell, they don’t need treating.
Tell me more about a urine infection (UTI) – symptoms, diagnosis and treatment.
4. What bacteria cause UTIs?
- The most common bacterium is Escherichia coli (in 70 to 95% of cases)
- Less commonly organisms include Staphylococcus saprophyticus (approximately 5-10% of cases), Proteus mirabilis (more common in males, associated with urinary tract abnormalities, particularly stones), and Klebsiella species
- Streptococci rarely cause uncomplicated UTI; although a type called Lancefield Group B streptococci may cause infection in some women
- Candida (a fungus) species rarely cause UTI. When they do, they are usually linked to indwelling catheters in the bladder, immunosuppression (drugs or diseases that suppress the immune system) or contamination from the genital area.
5. What are the symptoms of UTI?
UTIs don’t always cause symptoms. When they do, they may include:
- A strong urge to urinate that doesn’t go away
- A burning feeling when urinating
- Urinating often, and passing small amounts of urine
- Cloudy urine
- Urine that appears red, bright pink or cola-coloured = signs of blood in the urine
- Strong-smelling urine
- Pelvic pain, in women — especially in the centre of the lower tummy.
Elderly – in the elderly, they can present in very variable ways:
- Asymptomatic (no symptoms)
- Acute confusion (delerium) – that can be life threatening. The patient may be too confused, and/or unwell, to tell you they have urinary symptoms.
- Sepsis – that can be life threatening.
Note. UTIs may be overlooked or mistaken for other conditions.
6. Tell me more about the symptoms related to different types of UTI
Each type of UTI may result in more specific symptoms. The symptoms depend on which part of the urinary tract is affected.
If an infection is limited to the bladder (cystitis), it can be painful and annoying. But if a UTI is in a kidney, or gets into the bloodstream (sepsis), the illness can be severe or even life-threatening. The elderly are also vulnerable to UTIs, and may get serious problems, and need hospital admission.
Kidney (‘acute pyelonephritis’) – pain in the back or side pain, with high fever, shaking and chills and possibly nausea and vomiting. It usually affects one kidney.
Bladder (‘cystitis’) – part of a simple UTI – pelvic pain, lower belly discomfort, frequent and painful urination, blood in urine
Prostatitis (men only) – pain, which may be severe, can be around the penis, testicles, anus, lower abdomen or lower back – pooing can be painful. There can also be symptoms of urethritis (pain on urination).
Urethra (‘urethritis’) – part of a simple UTI: pain on urination, discharge from around entrance to urethra or end of penis
7. How are UTIs diagnosed (investigation)?
Urinary dipstick – they are often not done for a (low risk) simple UTI in a woman who has had them before. Guidance states treatment should be offered based on symptoms alone for young adults.
Midstream specimen of urine (MSU) – an MSU is a urine sample sent to the laboratory to check for white blood cells, red blood cells or bacteria. This is often followed by a urine culture. This test tells your doctor which bacterium is causing the infection. That helps your doctor know which antibiotic will be most effective.
8. What further investigations may be required?
Some people may need further investigation if symptoms are recurrent and not responding, or there is blood with no infection. Children are normally investigated.
Urinary tract ultrasound (US; kidneys, bladder and prostate) – this is not normally necessary. But if you are a man (or child), have acute pyelonephritis, or are very unwell, or have new recurrent UTIs, this may be caused by a structural problem (blockage somewhere). This may be due to a stone, cancer, or something else. Then you need an ultrasound. Your doctor may also organise a CT scan or MRI. A contrast dye may be used to highlight structures in your urinary tract.
Cystoscopy – this is not normally necessary. The reasons for having one are the same as for an ultrasound. A cystoscope is a telescope that looks inside the bladder. If required, one is inserted into the urethra and passed into the bladder.
Blood tests – these are not normally necessary. But if admitted to hospital, you should have these blood tests: FBC, U+E, LFT, bone, glucose, CRP and blood cultures.
9. How is a UTI treated?
Antibiotics commonly used for simple UTIs include, women usually need 3 days treatment and men 7 days.
- Trimethoprim (and co-trimoxazole, which is similar) – mainly children
- Nitrofurantoin (good for long term low dose prevention)
- Cephalexin
- Amoxycillin, co-amoxiclav
If very unwell
If you are very unwell, or have acute pyelonephritis, other treatment options are required. And you will usually need hospital admission for intravenous antibiotics and fluids. However, some women, especially older women, may have very subtle or no symptoms. If you experience a sudden increase in the need to urinate often, or start to leak urine involuntarily, UTI could be the cause – especially if this is a new problem.
Frequent infections
If you have frequent UTIs, and an underlying structural cause has been ruled out, your doctor may recommend low-dose antibiotics at night (nitrofurantoin is effective). You may need them for six months or longer. If this is required, you should be referred to a consultant urologist (urinary tract surgeon) at your local hospital.
10. What lifestyle changes can help women with recurrent UTIs?
Expert opinions vary on whether certain lifestyle changes reduce the risk of UTIs (in women where no underlying cause is found). It may be helpful to:
- Drink plenty of liquids, especially water
- Urinate often, especially when you feel the need
- Wipe from front to back after urinating or having a bowel movement
- Gently wash the skin around your vagina and anus daily using a mild soap and plenty of water
- Empty your bladder as soon as possible after sex
- Avoid using deodorant sprays or scented feminine products in the genital area.
Summary
We have described 10 UTI facts. Most UTIs are a simple illness, irritating but it does not make you that unwell – and respond well to antibiotics. But they can, occasionally, be serious or even life-threatening – and require hospital admission. If the problem recurs, or you are very unwell, or a man or child, you may need further investigation for an underlying cause.
Other resources
MyHSN has a related article.
Recurrent UTIs
This is useful information for patients from the NHS in Scotland.
These are two review articles for health professionals.
https://academic.oup.com/cid/article/38/8/1150/441696
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4457377
This is a good video from the USA.
https://www.youtube.com/watch?v=t5-__3vwQ9M
Last Reviewed on 23 August 2023