A bladder infection (cystitis) usually occurs when bacteria travel up the urethra, enter the bladder, and begin to multiply. Women develop far more episodes of cystitis because the urethra is shorter, allowing bacteria faster access to the bladder. Any abnormality of the urinary tract which obstructs the flow of urine sets the stage for a UTI.

One common source of infections are tubes, or catheters, placed in the bladder. Bacteria, which normally live on the skin or in the environment, can essentially "crawl up" the catheter and infect the bladder. People who cannot void or who are critically ill sometimes need catheters permanently, and are at high risk. People with diabetes are also at an increased risk because of changes in the immune system. Men with enlarged prostates whose bladders do not fully empty are also at risk for bladder infections.

Symptoms of a lower tract UTI include a frequent urge to urinate and a burning sensation and/or pain upon urination. Suffers often complain that even though they have a sense of urgency to urinate, only a small amount of urine is passed. The urine may look cloudy and may have blood in it. Many times, women feel pressure in the lower abdomen above their pubic bone and men may feel a sense of fullness in their rectum. Intercourse can also be painful. Some signs and symptoms of an upper tract UTI include lower tract symptoms accompanied by high fever, nausea, vomiting, fatigue, chills, back pain, and bloating.

If you suspect that you have a UTI, you should consult your physician immediately. Your physician will take a detailed medical history and ask you to provide a urine sample upon which a urinalysis test will be performed. If the urinalysis test reveals an infection, then a culture will be performed on the urine to identify the organisms causing the infection. In addition to a urinalysis, you may also undergo a sonogram of your bladder and kidneys and/or a cystoscopy. These tests may or may not be ordered by your physician. During a cystoscopy, a urologist looks inside the bladder with a lighted telescope. It is recommended only in certain circumstances.