A Urinary Tract Infection (UTI) is an infection involving the kidneys, ureters, bladder, or urethra. These are the structures that urine passes through before being eliminated from the body. Any part of this system can become infected. As a rule, the farther up in the Urinary Tractthe infection is located, the more serious it is. Urinary tract infections are much more common in adults than in children, but about 1%-2% of children do get urinary tract infections. Urinary tract infections in children are more likely to be serious than those in adults and should not be ignored (especially in younger children).
- The upper urinary tract is composed of the kidneys and ureters. Infection in the upper urinary tract generally affects the kidneys (pyelonephritis), which can cause fever, chills, nausea, vomiting, and other severe symptoms.
- The lower urinary tract consists of the bladder and the urethra. Infection in the lower urinary tract can affect the urethra (urethritis) or the bladder (cystitis).
Causes of Urinary Tract Infection
The urine is normally sterile. An infection occurs when bacteria get into the urine and begin to grow. The infection usually starts at the opening of the urethra where the urine leaves the body and moves upward into the urinary tract.
- The culprit in at least 90% of uncomplicated infections is a type of bacteria called Escherichia coli, better knows as E. coli. These bacteria normally live in the bowel (colon) and around the anus.
- These bacteria can move from the area around the anus to the opening of the urethra. The two most common causes of this are poor hygiene and sexual intercourse.
- Usually, the act of emptying the bladder (urinating) flushes the bacteria out of the urethra. If there are too many bacteria, urinating may not stop their spread.
- The bacteria can travel up the urethra to the bladder, where they can grow and cause an infection.
- The infection can spread further as the bacteria move up from the bladder via the ureters.
- If they reach the kidney, they can cause a kidney infection (pyelonephritis), which can become a very serious condition if not treated promptly.
Risk Factors of Urinary Tract Infection
The following people are at increased risk of urinary tract infection:
- People with conditions that block (obstruct) the urinary tract, such as kidney stones
- People with medical conditions that cause incomplete bladder emptying (for example, spinal cord injury or bladder decompensation after menopause)
- People with suppressed immune systems: Examples of situations in which the immune system is suppressed are AIDS and diabetes. People who take immunosuppressant medications such as chemotherapy for cancer also are at increased risk.
- Women who are sexually active
- Women who use a diaphragm for birth control
- Men with an enlarged prostate: Prostatitis or obstruction of the urethra by an enlarged prostate can lead to incomplete bladder emptying, thus increasing the risk of infection. This is most common in older men.
- Males are also less likely to develop UTIs because their urethra (tube from the bladder) is longer. There is a drier environment where a man’s urethra meets the outside world, and fluid produced in the prostate can fight bacteria.
- Breastfeeding has been found to decrease the risk for urinary tract infections.
The following special groups may be at increased risk of urinary tract infection:
- Very young infants: Bacteria gain entry to the urinary tract via the bloodstream from other sites in the body.
- Young children: Young children have trouble wiping them and washing their hands well after a bowel movement. Poor hygiene has been linked to an increased frequency of urinary tract infections.
- Children of all ages: Urinary tract infection in children can be (but is not always) a sign of an abnormality in the urinary tract, usually a partial blockage. An example is a condition in which urine moves backward from the bladder up the ureters (vesicoureteral reflux).
- Hospitalized patients or nursing home residents: Many of these individuals are catheterized for long periods and are thus vulnerable to infection of the urinary tract. Catheterization means that a thin tube (catheter) is placed in the urethra to drain urine from the bladder. This is done for people who have problems urinating or cannot reach a toilet to urinate on their own.
Prevention of Urinary Tract Infection (UTI)
These are steps you can take to try to prevent a UTI:-
- Urinate when you need to. Don’t hold it.
- Pass urine before and after sex. After you pass urine or have a bowel movement (BM), wipe from front to back.
- Drink water every day and after sex. Try for 6 to 8 glasses a day.
- Clean after urination and bowl movement.
- Don’t use douches or feminine hygiene sprays.
- Wear underpants with a cotton crotch. Don’t wear tight-fitting pants, which can trap in moisture.
- Take showers instead of tub baths.
Symptoms of Urinary Tract
Symptoms differ, depending on whether the infection affects the lower (bladder and urethra) or upper (kidneys and ureters) parts of the urinary tract. The Symptoms of Lower Urinary Tract Infection are dysuria (burning on passing urine), frequency (frequent need to pass urine) and urgency (compelling need to urinate). The urine can be cloudy with an offensive odour. In older men, generalized symptoms such as confusion and incontinence can be present. Urine Infections are much commoner in the elderly, due to poor bladder emptying, an enlarged prostate, or incontinence associated with Stroke or Dementia. The Symptoms of Upper Urinary Tract Infection are the same as lower tract symptoms plus loin (flank) pain, fever and chills. The patient is likely to be ill and might require hospital admission.
Diagnosis of Urinary Tract Infection
Test strips dipped into a urine sample can detect indirect signs of infection such as blood, protein, white blood cells and nitrites (most common bacteria convert nitrate, which is a chemical normally present in urine into nitrites, which are not usually present). A clean midstream urine sample should be sent to the laboratory for a microscopy examination. A level of 100,000 bacteria per millilitre of urine is regarded as a significant infection, especially if found together with pus or white blood cells (leucocytes) on microscopy. Any infecting bacteria are cultured in the laboratory to assess their sensitivity to common antibiotics.
Treatment of Urinary Tract Infection
A high fluid intake is essential. Alkaline substances, such as citrates, taken in water might improve symptoms. By making the urine more alkaline, they make the environment more hostile to bacterial growth and improve the results of antibiotic therapy.
Antibiotics are the mainstay of treatment. Trimethoprim (eg Monotrim) is currently the first choice for lower UTI in the UK, because it’s cost-effective, well tolerated and works in 80 per cent of infections. Cephalosporins, nitrofurantoin and norfloxacin are reserved as second line drugs in patients with lower UTI. But they are the first choices in patients with signs of upper UTI or kidney infection. Antibiotics, such as amoxicillin, now have resistance levels of 50 per cent in the community because of widespread use over many years. Based on such experiences, many specialists are concerned about the possible overuse of the more powerful antibiotics as first line therapy in the general community.
If UTIs keep occurring, identification and treatment of the underlying cause is essential. Patients who have the same infection coming back can be managed successfully by attending to ‘bladder toilet’ (drinking 2 to 3 litres of fluid daily and always passing urine at bedtime and after sex). Drinking 250 to 500ml of cranberry juice daily and avoidance of bubble baths may also help. If these measures fail, six months of continuous therapy with low dose antibiotics is usually required.