Cystitis is a bacterial infection of the bladder or lower urinary tract.

Cystitis occurs when the lower urinary tract (urethra and bladder) is infected by bacteria and becomes irritated and inflamed. More than 85% of cases of cystitis are caused by Escherichia coli (E. coli), a bacteria found in the lower gastrointestinal tract. Sexual intercourse may increase the risk of cystitis because bacteria can pass from the urethra to the bladder during sexual activity. When you urinate, you help remove bacteria from the bladder. If the bacteria grows faster than it is removed by urination, an infection results.

The condition is very common, and frequently affects sexually active women ages 20 to 50. However, it may also occur in those who are not sexually active.

Cystitis is rare in males. Women are more prone to develop cystitis because they have shorter urethras than men, and bacteria does not have to travel as far to enter the bladder. The distance between the opening of the urethra and the anus is also shorter in women than men.

Older adults are also at high risk for developing cystitis. Rates of cystitis are much higher among the elderly than in younger people. This is due in part to conditions that cause an incomplete emptying of the bladder such as benign prostatic hyperplasia (BPH), prostatitis, and urethral strictures. Not drinking enough fluids, bowel incontinence, and immobility or decreased mobility, increased one's risk for cystitis.

Other risk factor for cystitis include blockage of the bladder or urethra, insertion of instruments into the urinary tract (such as catheterization or cystoscopy), pregnancy, diabetes, HIV, and a history of analgesic nephropathy or reflux nephropathy.

• Pressure in the lower pelvis
• Painful urination (dysuria)
• Frequent or urgent need to urinate
• Need to urinate at night (nocturia)
• Abnormal urine color (cloudy)
• Blood in the urine (hematuria)
• Foul or strong urine odor

• Pain during sexual intercourse
• Penis pain (rare)
• Flank pain
• Fatigue
• Fever
• Chills
• Nausea and vomiting
• Mental changes or confusion *

Urinalysis commonly shows white blood cells (WBCs) or red blood cells (RBCs).

Urine culture (clean catch) or catheterized urine specimen may be done to find out what kind of bacteria is causing the infection and to determine the appropriate antibiotic for treatment.

Cystitis should be promptly treated. Antibiotics are used to fight the bacterial infection. You should finish the entire course of antibiotics. Commonly used antibiotics include:

• Nitrofurantoin
• Sulfa drugs (sulfonamides) such as trimethoprim-sulfamethoxazole (Bactrim)
• Amoxicillin
• Cephalosporins
• Ciprofloxacin or levofloxacin
• Doxycycline

Another medication called Pyridium may be used to reduce the burning and urgency associated with cystitis. In addition, common products that increase acid in the urine, such as ascorbic acid or cranberry juice, may be recommended to decrease the concentration of bacteria in the urine.

Follow-up may include urine cultures to make sure that bacterial infection is gone.

Most cases of cystitis are uncomfortable but disappear without complication after treatment.

• Chronic or recurrent urinary tract infection
• Complicated UTI (pyelonephritis)
• Acute renal failure

Call your health care provider if you have symptoms of cystitis, or if you have already been diagnosed and symptoms get worse. You should also call if new symptoms develop, particularly fever, back pain, stomach pain, or vomiting.

Keeping the genital area clean and wiping from front to back may reduce the chance of introducing bacteria from the rectal area to the urethra.

Drink plenty of fluids to allow for frequent urination to flush the bacteria from the bladder.

Urinating immediately after sexual intercourse may help eliminate any bacteria that may have been introduced during intercourse. If you do not urinate for a long period of time, the bacteria has time to multiply. Frequent urinating may reduce risk of cystitis in those who are prone to urinary tract infections.

Drinking cranberry juice prevents certain types of bacteria from attaching to the wall of the bladder and may reduce your risk of infection.