What is the urinary tract?
The urinary tract system consists of two kidneys, each with a draining ureter into the urinary bladder and the urethra through which urine is expelled from the body. Urine is produced by the kidneys as a filtrate from blood which has passed through the kidneys. Waste material and substances in excess is excreted into the urine by the kidney during the process of filtration and processing in the tubules and drained into the bladder through its ureter (see diagram). Urine is stored in the urinary bladder until it is passed out from the body through the urethra.
What is Urinary Tract Infection?
Urinary Tract Infection (UTI) refers to an infection in the urinary tract. It has been said that it is the next most common infection in women after the common ‘flu’. Under normal circumstances, the urinary tract is sterile or free from bacteria. Most of these infections are caused by germs (bacteria) existing in the intestinal tract and are passed out from the rectum through the anus. They stick to the skin around the genital areas. In an infection, these germs find their way up the urinary tract through the opening of the urethra. The most common bacteria is the Escherichia coli (E. Coli).
Some infections seem to be more severe than others.
Are there different types of UTI?
Severity usually depends on which part of the urinary tract is affected and whether the urinary tract is normal in structure. Infection can be classified into two types – uncomplicated and complicated.
1) Uncomplicated UTIs occur in persons without physiologic or anatomic abnormalities of the urinary tract and in the absence of recent urinary tract surgery. They are community acquired (outside of hospital) and can be divided into two groups depending on the localisation of the infection:
• Acute cystitis - lower urinary tract infection affecting the bladder
• Acute pyelonephritis - upper urinary tract infection affecting the kidney itself
2) Complicated UTIs occur in persons with obstruction, structure, or have disorders of the urinary tract that affect its function such as kidney failure.
Some conditions predispose one to getting an infection.
These include:
• Use of a urinary catheter (tube) that drains the bladder of urine when patients are unable to pass on their own. This can be left in place or inserted intermittently 6 to 8 times a day.
• Urinary instrumentation or surgery to the urine tract
• Incomplete voiding or urine left in the bladder from obstruction which may occur in elderly men with a large prostate, uterine prolapse in elderly ladies
• Presence of kidney stones
• Vesicoureteral reflux – the passage of urine from the bladder back into a ureter due to a developmental abnormality causing a faulty valve at the junction of the ureter with the bladder
• Pregnancy – because of physical changes that occur during pregnancy.
• Diabetics get more severe infections because of changes in the immune system
Who will get UTI?
It happens to both adults and children regardless of sex. Some people are more prone to getting a UTI than others.
It is more common:
• When the urinary tract is abnormal because of a developmental abnormality or
• With a disease process, urinary catheters (tubes) are used to drain urine or
• Persons who are critically ill or unconscious.
Do persons with normal urinary tract get UTI?
Certainly! Women with normal urine tract are up to 30 – 40 times more prone to getting UTI than men. This is due to the short length of the urethra in women, which allow bacteria easy access from the outside to enter the bladder. The urethral opening is also very close to the anus and vaginal areas where bacteria are present. Sexual activity in women also increases the risk of getting a UTI.
How will I know that I have an episode of UTI?
You may experience one or more of the following symptoms:
• Frequency, urgent need to urinate
• Burning sensation around the private parts when urinating
• Lower abdominal pain
• Milky or cloudy urine
• Unpleasant-smelling urine
• Blood or pus in the urine
• Lower back pain and
• Fever
Not all of these problems may be present at the same time.
Can UTI be prevented?
Episodes of UTI can be prevented by:
• Practicing good personal hygiene. This is especially important in women where the short urethra allows bacteria to travel into the bladder easily from the skin outside of the body.
• Drink plenty of water everyday (2 – 2.5 L/day). The urine produced can flush the urethra of the bacteria
• Take showers instead of soaking in the bathtub
• Urinate when you feel the need, avoid overstretching the bladder
For females:
• After micturation or a bowel motion where washing is not possible, wipe from front (the “clean area”) to the back (the “less clean area”) after urination to prevent bacteria around the anus from entering the vagina or urethra.
• Make sure both partners wash the perineal area before and after sex to reduce the numbers of bacteria present on the skin around the area.
How do I confirm that I have UTI?
Confirmation is done through urine tests performed to look for the presence of white blood cells. The white blood cells increase with the amount of inflammation. These can be detected using dipstick reagent strips or by looking at the urine through a microscope and the amount of white blood cells counted. Often red blood cells are also present. The urine can also be cultured for bacterial growth and tested against a range of antibiotics to assist the doctor in the choice of antibiotic should the initial treatment be unsuccessful. However, culture is not useful once antibiotics have been started, as the bacteria often would not grow in the presence of antibiotics.
In order to have an accurate diagnosis, the method of collecting urine specimen is very important. This is because contamination can occur from the skin surface as well as vaginal secretions in the female and smegma in the male. The cells seen on microscopy may be coming from contaminants rather than the urine itself. The nurse in the clinic will instruct you on how to collect a midstream urine specimen to avoid this problem. It is important to follow these instructions to avoid getting a contaminated sample.
Since there may be other causes leading to UTI, are investigations performed to look for a cause in every case of UTI?
Not all cases of UTI are investigated. Your doctor will decide if further tests are required. Some of the tests may include:
| • | Intravenous urogram (IVU)
In this test, an opaque dye is injected into a vein to give X-ray images of the bladder, kidneys and ureters to look for abnormalities in the urine tract |
| • | Cystoscopy
An instrument that allows the doctor to see the inside of the bladder from the urethra |
| • | Ultrasound examination
This examination is performed using sound waves to look for obstruction in the urine tract. |
How is UTI treated?
Treatment includes antibiotics to get rid of bacteria. This may take a few days. In the meantime pain relievers can be taken at the same time. Drinking plenty of water will also help to flush bacteria as well as diluting the amount of bacteria.
It is important to complete the course of antibiotics as the UTI may recur if the bacteria are not destroyed completely. More importantly, the bacteria that initially caused the infection would become resistant to the antibiotic previously used and a new course with another antibiotic would have to be started.
I get recurrent UTI, what can be done about this?
Recurrent UTI should be investigated to search for an underlying cause so that it can be eradicated or corrected.
For those females who have normal urine tracts, a course of preventive antibiotics can be prescribed.
Can UTI lead to kidney failure?
Fortunately, with prompt treatment UTI is quite unlikely to lead to kidney failure. However, if a person has urinary tract obstruction, reflux or some other urinary abnormalities, infection may lead to progressive damage of the kidneys.
Always remember two most important things to do to prevent further infections:
• Practice good hygiene
• Drink plenty of water
You may visit these websites for more information:
http://www.davita.com
http://www.uptodate.com/patients/index.html |