Definition of urinary tract infection
A UTI is an infection that can affect one or more parts of the urinary system: the kidneys, the ureters, the bladder and the urethra. It is most often manifested by pain or a burning sensation when urinating (= the emission of urine), sometimes by abdominal pain and fever.
Here are the main functions of different parts of the urinary system:
- The kidneys provide filtration of the blood. They allow waste disposal and also play an important role in the regulation of body fluids and blood pressure.
- The ureters are small channels that allow the passage of urine from the kidneys to the bladder.
- The bladder acts as a reservoir of urine.
- The urethra leads urine from the bladder to the outside of the body.
The different types of urinary tract infections
There are 3 types of urinary tract infections, depending on the location of the infection.
Infectious cystitis, when Escherichia coli is found in the urine
By far the most common form of urinary tract infection, cystitis affects almost only women. It is an inflammation of the bladder. In most cases, inflammation is caused by the proliferation of intestinal Escherichia coli bacteria, which are numerous around the anus. Bacteria move from the anal and vulvar area to the bladder up the urethra. Anything that hinders the emptying of the bladder increases the risk of cystitis, as it increases the retention of urine, so the proliferation time of bacteria. Cystitis is always accompanied by urethritis, the inflammation of the urethra.
If the infection only affects the urethra (the duct that connects the bladder to the urinary meatus), it is called urethritis. These are often common sexually transmitted infections (STIs) in men. And women can also suffer. Different infectious agents can cause urethritis. The most common are chlamydia and gonococcus (the bacteria responsible for gonorrhea). In men, urethritis may be accompanied by prostatitis (infection of the prostate).
Pyelonephritis is a more serious condition. It refers to the inflammation of the pelvis (the cavity of the kidney collecting the urine) and the kidney itself. This usually results from a bacterial infection. It can be a complication of untreated or poorly treated cystitis that leads to the rise of bacteria from the bladder to the kidneys, and their proliferation at this level. Acute pyelonephritis occurs more often in women, and is even more common in pregnant women. It is also common in children whose malformation of the ureters causes a reflux of urine from the bladder to the kidneys.
Most affected by urinary tract infections: men or women?
The frequency of urinary tract infections depends on age and sex.
Urinary tract infection in women
The women are more affected than men because the urethra of the woman, shorter than that of man, facilitates the entry of bacteria into the bladder. It is estimated that in North America, 20% to 40% of women have had at least one urinary tract infection. Many women will contract many during their lifetime. About 2% to 3% of adult women would have cystitis each year.
Urinary tract infection in humans
Young men are unaffected by this condition, with older men with prostate disorders at higher risk.
As for children, they are more rarely affected. About 2% of newborns and infants contract urinary tract infections. It is mostly male babies who have an abnormality of the urinary tract that suffer from it. At the age of 6,7% of girls and 2% of boys experienced at least once a urinary tract infection .
Causes Urinary tract infection
Normally, the urine is sterile. It contains 96% water, salts and organic components, but is free of micro-organisms. The urinary system has many defenses against infections:
– Urinary flow expels bacteria and makes it more difficult to ascend to the bladder and kidneys;
– the acidity of the urine (pH below 5.5) inhibits the growth of bacteria;
– l was very smooth surface of the urethra makes difficult the recovery of bacteria;
– the shape of the ureters and bladder prevents the rise of urine to the kidneys;
– the immune system in general fights against infections;
the wall of the bladder contains immune cells as well as antibacterial substances;
– in men, secretions prostate contain substances that slow the growth of bacteria in the urethra.
However, in case of urinary infection, infectious agents (most of them bacteria) manage to “colonize” the urinary system. The urine is then contaminated: it is by looking for the presence of bacteria in the urine that the doctor confirms the diagnosis of urinary infection. Bacterial contamination is often facilitated by not drinking enough.
In over 80% of urinary tract infections, the causative organism is an intestinal bacteria type Escherichia coli. Other commonly found bacteria are Proteus mirabilis, Staphylococcus saprophyticus, Klebsiella … Some sexually transmitted infections (gonococcal, Chlamydiae) can also manifest as urethritis.
Very rarely, urinary infections can be caused by bacteria that have spread to the urinary system from an infection elsewhere in the body.
|A question of anatomy
In women, the proximity between the anus and the external orifice of the urethra (the urinary meatus) greatly facilitates the access of the urethra to intestinal bacteria from the rectum (enterobacteria), such as Escherichia coli. Moreover, the female urethra being very short (barely 4 cm); this facilitates the access of bacteria to the bladder. In addition, pregnancy, the use of a diaphragm as a means of contraception and the use of tampons during menstruation increase the risk of urinary tract infection.
In young men, urinary tract infection (especially urethritis) is often linked to sexual activity. In an older man, she is more often associated with prostate disorders. For example, when a man over 50 has a urinary tract infection, it is almost always linked to a benign prostatic hypertrophy or an inflammation that prevents the bladder from emptying completely.
In children, the urinary tract infection can be a sign of an anatomical abnormality of the urinary system and must absolutely be treated by a doctor in order to avoid that the urinary disorders become chronic.
In general, when a person has a chronic problem in the urinary tract (anatomical malformation, kidney or bladder disease, stones or “stones” in the urine), it is not uncommon for her to suffer recurrent infections.
Possible complications Urinary tract infection
If the infection is not treated, the infectious agent continues to multiply and invade the urinary tract. This can lead to a more serious kidney problem, such as pyelonephritis. Exceptionally, a urinary infection can worsen to the point of sepsis or kidney failure. In any case, it is important to consult a doctor in case of signs of urinary infection.
Symptoms of urinary tract infection
Most common symptoms
- Of pain or burning when urinating.
- An abnormally high frequency of urination during the day (sometimes the need to urinate also occurs at night).
- A persistent feeling of needing to urinate.
- Disturbed urine that gives off an unpleasant odor.
- Gravity in the lower abdomen.
- Sometimes blood in the urine.
- No fever if it is a simple cystitis.
In the case of a kidney infection
- High fever
- Intense pain in the lower back or abdomen or sexual organs.
- An alteration of the general state.
- Symptoms of cystitis (burns, frequent urge to urinate) may or may not be present. They are absent in 40% of the cases.
In children, urinary tract infections may be more atypical. Sometimes, cystitis causes fever without any other symptoms. A stomach ache and enuresis (bedwetting) can also be a sign of urinary tract infection. In toddlers, the burning sensation during urination can be manifested by complaints or crying when urinating.
In neonates and infants, urinary tract infection is even more difficult to recognize. It generally causes fever, refusal to eat, and sometimes gastrointestinal disturbances and irritability.
In the elderly:
The symptoms of urinary infection can also be misleading: fever without other symptoms, urinary incontinence or digestive disorders (loss of appetite, vomiting …).
|See also: How to interpret the result of a urine test?|
People at risk of urinary tract infection
- Women, especially those who are sexually active. The infection rate is 50 times higher than in men.
- Men with benign prostatic hypertrophy or prostatitis (inflammation of the prostate). When it increases in size, the prostate compresses the urethra, which slows the evacuation of urine, increases the risk of keeping some residual urine in the bladder after urination and facilitates infections.
- Pregnant women are particularly at risk because of the pressure exerted by the baby on the urinary system, but also hormonal changes inherent to pregnancy.
- Women after menopause, who are more prone to vaginosis, vaginal bacterial infections. In addition, the decline in estrogen levels associated with menopause contributes to urinary tract infections.
- People with diabetes, because of the high level of sugar in their urine, which is a favorable environment for bacterial development, and their increased susceptibility to infections.
- People who have had a catheter inserted into the urethra. People who cannot urinate, who are unconscious or seriously ill often need a catheter for the time to regain their urinary function. Some people who have a nervous system disorder will need it all their lives. The bacteria then move up the surface of the bladder to the bladder and can infect the urinary tract. When contracted at the hospital, these bacteria have developed some resistance requiring the use of more potent antibiotics.
- People who have a structural abnormality of the urinary tract, who suffer from kidney stones or various neurological disorders.
- The elderly, who often combine many of the above factors (bed rest, hospitalization, urinary catheter, neurological disorders, diabetes). Thus, 25% to 50% of women and 20% of men over 80 are prone to frequent urinary tract infections.
Risk factors for urinary tract infection
- Sexual intercourse, especially if it is intense and frequent after a period of abstinence. This phenomenon is described as “cystitis of the honeymoon”.
- In some women using a diaphragm as a means of contraception, the urethra will be compressed, preventing the bladder from emptying completely and facilitating bladder infections.
- After going to the saddle, wiping from the back to the front with the toilet paper is a risk factor. The wiping motion should always be from front to back so as not to contaminate the urethra with bacteria from the anus. In addition, the anal and genital areas must be carefully cleaned regularly, which helps to counter the proliferation of bacteria.
- In some women, the use of spermicides can cause urethritis.
- The time of menses is a risky time, as the blood of towels or tampons is an ideal culture medium for bacteria. So it is important not to keep these protections in place for too long.
- Condomless sodomy increases the risk of getting infected, with the bacteria involved in the anus.
Prevention of urinary tract infection
|Basic preventive measures|
Tips to reduce the risk of urinary tract infection
It is more difficult to prevent urinary tract infections in men. It is important to drink enough to maintain a good urine flow, and to treat a prostate disorder if necessary. In addition, the urethritis corresponding to sexually transmitted infections can be prevented by using the condomduring sex with any new (or new) partner. Inflammation of the urethra is common in men who develop gonorrhea or chlamydia.
|Measures to prevent complications|
|Treating bladder infections with antibiotics prevents pyelonephritis, a much more serious infection.
It is important not to treat one, for example by taking the remaining antibiotics from a previous treatment. Using antibiotics inappropriately without following the prescribing guidelines may make cystitis difficult to treat and make the situation worse.
|Measures to prevent recurrence|
|Recurrent urinary tract infections are very common in women. In addition to the preventive measures mentioned above, drug or natural prevention can be effective.
Prevention with drugs
In some patients for whom urinary tract infections are common (more than 2 infections every 6 months), antibiotics may be prescribed as a low dose preventive for several months. The same is true for men with chronic prostate problems that increase the risk of urinary tract infection.
Thus, the doctor can prescribe antibiotics daily for a few months or after each sexual intercourse to prevent relapses and allow the immune system to regain control. We talk about prophylactic antibiotic therapy.
Prevention with cranberry juice
Regularly consumed cranberry juice reduces the risk of recurrent urinary tract infections in women, as shown by several studies or meta-analyzes. See the Complementary Approaches section.
Medical treatments for urinary tract infection
What to do in case of benign urinary infections (urethritis, cystitis)?
The urinary bacterial infections can be treated easily and quickly with the help of antibiotics. For cases caused by E. coli , the physician uses a variety of antibiotics including amoxicillin (Clamoxyl, Amoxil, Trimox), nitrofurantoin (Macrodantin, Furadantin), sulfamethoxazole plus trimethoprim (Bactrim, Eusaprim, Septra) and trimethoprim alone (Trimpex, Proloprim). The choice of antibiotic is initially blind and then based on the results of the urine test as soon as they are available.
It can be administered as a single dose or a 3, 7 or 14 day regimen. In the majority of cases, a 3-day therapy is proposed (trimethoprim-sulfamethoxazole). When the infection appears a few days after unprotected sex , the doctor will make sure that it is not sexually transmitted infection (STI) (gonorrhea or chlamydia), which would justify a particular antibiotic treatment.
Once treated, symptoms usually disappear within 24 to 48 hours, sometimes less. It is important, however, that the duration of the prescription be followed to the letter. If the antibiotic chosen is not effective after 48 hours, inform your doctor, who can then suggest another.
To promote the elimination of bacteria, it is also necessary to drink more than usual during treatment. People who experience pain or pressure in the lower abdomen can get relief by taking painkillers. You can also place a hot compress on the abdomen.
The pregnant women are subject to systematic screening. It is indeed very important to detect the presence of a urinary infection during pregnancy and to treat it if necessary. In one-third of cases, the infection can spread to the kidneys with the possibility of premature delivery or a low birth weight baby. Safe antibiotics for the mother and fetus will be offered even if the infection is not accompanied by symptoms.
What to do in case of serious urinary tract infections (pyelonephritis)?
|Although most urinary tract infections are simple to treat, specialist consultation is sometimes necessary as cystitis may indicate the presence of a more serious illness or abnormality . For example, men of all ages, women with recurrent urinary tract infections, pregnant women, and people with pyelonephritis (kidney infection) are among the most difficult cases to treat. They may have to be seen by an urologist, the specialist in the urinary system, for further analysis.
As for pyelonephritis, it often comes under emergency care .
If symptoms of cystitis persist after 1 week despite well-followed antibiotic treatment, it may be an antibiotic-resistant infectioncommon. This is often the case for infections acquired in hospital, for example because of a urethral catheter or surgical procedure. Cystitis contracted outside hospitals is also increasingly resistant to antibiotic therapy. The doctor will then prescribe the appropriate antibiotics based on the results of a bacterial culture made from a urine sample. It should be noted that the risk of infection from a urethral catheter can be reduced by using a sterile, tight urine collection system, antiseptic ointments, and short-term antibiotics.
Pyelonephritis (kidney infection)
Pyelonephritis can be treated with a high-dose oral antibiotic, usually a fluoroquinolone (Oflocet, Cipro, Levaquin, Oflox …). The treatment will then be continued for 14 days (sometimes 7). In severe cases, hospitalization is necessary and antibiotics can be given by injection.
In humans , a urinary tract infection with pain in the lower abdomen or fever may be complicated by prostatitis (diagnosed by a rectal examination performed by the doctor). This situation requires antibiotic treatment for 3 weeks, with antibiotics similar to those used for pyelonephritis.
Obstruction of the urinary system
In rare cases, the urinary tract infection may be related to urinary tract obstruction. This is a medical emergency . The cause of the obstruction (hypertrophied prostate, anatomical anomaly, kidney stones, etc.), revealed by an ultrasound, must be managed quickly. An intervention allowing drainage of the urine is necessary.
|Important. People who have a urinary tract infection should temporarily avoid coffee, alcohol, caffeinated soft drinks and citrus juices. Spicy foods should also be set aside until the infection is cured. These foods irritate the bladder and make you want to urinate even more frequently. In addition, the doctors remind to hydrate well and to adopt the preventive measures described previously.|