A urinary tract infection, or cystitis, is an infection caused by microbes. These are organisms visible only under the microscope. Most urinary tract infections are caused by bacteria, but some are caused by fungi and, in rare cases, by viruses. Urinary tract infections are among the most common infections in humans.
A urinary tract infection can occur anywhere in your urinary tract. Your urinary tract consists of your kidneys, your ureters, your bladder and your urethra. Most urinary tract infections only affect the urethra and bladder in the lower tract. However, cystitis may involve the ureters and kidneys in the upper tract. Although urinary tract infections are less common than urinary tract infections, they are usually more serious.
A urinary tract infection is where the bacteria enter your urine and move to your bladder. Urinary tract infections account for over 8.1 million health care provider consultations each year. About 10 in 25 women and 3 in 25 men experience the symptoms of cystitis at least once in their lifetime.
How does the urinary tract work?
The urinary tract produces and stores urine, one of the waste products of your body. Urine is produced in the kidneys and descends along the ureters to the bladder. The bladder stores urine until it is emptied through the urethra, a tube that connects the bladder to the skin when you urinate. The opening of the urethra is at the end of the penis in a man, and in front of the vagina in a woman.
The kidneys are a pair of fist-sized organs that filter liquid waste from the blood and remove it from the body as urine. The kidneys regulate the content of many minerals in the body (sodium, potassium, calcium, phosphorus and others), and ensure the acidity of the blood. Some hormones are also made in the kidneys. These hormones help control blood pressure, stimulate red blood cell production and strengthen bones.
Normal urine does not contain bacteria, and unidirectional flow helps prevent urinary tract infections. Nevertheless, bacteria can enter the urine from the urethra, and move up to the bladder.
Types of urinary tract infections (cystitis)
Urinary tract infections are caused by microorganisms or germs, usually bacteria. The different types of cystitis can include:
- Urethritis, infection of the urethra
- Cystitis, bladder infection
- Pyelonephritis, infection of the kidneys
- Vaginitis, infection of the vagina.
Symptoms of urinary tract infection
The symptoms of a urinary tract infection depend on the part of the urinary tract infected. Cystitis of the lower tract affects the urethra and bladder.
Symptoms of cystitis of the lower tract include:
- to burn while urinating
- increased frequency of urination without letting a lot of urine pass
- increased urgency of urination
- bloody urine
- cloudy urine
- urine that looks like cola or tea
- urine that has a strong smell
- pelvic pain in women
- rectal pain in men
Urinary tract infections of the upper tract affect the kidneys. These can be potentially life threatening if bacteria move from the infected kidney to the bloodstream. This condition, called urosepsis, can cause dangerously low blood pressure and shock before death.
Symptoms of upper-tract cystitis include:
- pain and tenderness in the upper back and sides
Symptoms of a urinary infection in men
The symptoms of an upper urinary tract infection in men are similar to those of women. Symptoms of lower urinary tract infection in men sometimes include rectal pain, in addition to symptoms common to men and women.
Symptoms of a kidney infection
If the infection reaches the kidneys, an urgent medical consultation is necessary. In addition to the general symptoms of urinary tract infections, a person with kidney infection may also suffer from:
- pain in the loin (lower abdomen)
- back pain
Symptoms of urinary tract infection in women
Women with urinary tract infections of the lower urinary tract may experience pelvic pain. This is in addition to other common symptoms. The symptoms of an upper urinary tract infection in men and women are similar.
Treatment of urinary tract infections (cystitis)
The treatment of cystitis depends on its cause. Your doctor will be able to determine which organism is causing the urinary tract infection, based on the results of the tests used to confirm the diagnosis.
In most cases, the cause is of bacterial origin. Urinary tract infections caused by bacteria are treated with antibiotics.
In some cases, viruses or fungi are at the origin. Viral cystitis is treated with drugs called antivirals. Often, the antiviral cidofovir is recommended to treat viral urinary infections. Fungal infections are treated with drugs called antifungals.
Antibiotics to cure a cystitis
The form of antibiotic used to treat a bacterial infection usually depends on the part of the tract concerned. Urinary tract infections can usually be treated with oral antibiotics. Upper-tract cystitis requires the administration of intravenous antibiotics. These antibiotics are placed directly in your veins.
Sometimes, bacteria develop resistance to antibiotics. The results of your urine culture can help your doctor choose the most effective antibiotic treatment for cystitis against the type of bacteria that causes your infection.
Treatments other than antibiotics for bacterial urinary tract infections are under study. At some point, treatment of antibiotic-free cystitis may be an option for bacterial urinary tract infections, using cell chemistry to alter the interaction between the body and the bacteria. Antibiotics are the mainstay of treatment for cystitis.
The following oral antibiotics are commonly used to treat most urinary tract infections (acute cystitis):
- Sulfamethoxazole-trimethoprim (Bactrim DS, Septra DS, others) – price starts from $280.
- Nitrofurantoin (Macrobid, Macrodantin) – $54.99.
- Fosfomycin (Monurol) – $110.05 and $89.05 with Monurol coupon.
- Amoxicillin / clavulanate (Augmentin) – $966
- Some cephalosporins like cefpodoxime, cefdinir or cefaclor – $107.45.
Some measures can help prevent urinary tract infections in women. For menopausal women, the use of topical estrogens prescribed by your doctor could make a difference in the prevention of urinary tract infections. If your doctor says that intercourse is a factor in your recurrent cystitis, he may recommend taking preventive antibiotics after sex or long term. Some studies have shown that long-term preventative use of antibiotics in the elderly reduces the risk of urinary tract infections.