Cystitis is caused by germs, usually bacteria that enter the urethra and then the bladder. These bacteria can lead to infection, most commonly in the bladder. The infection can spread to the kidneys.
Most of the time, your body can get rid of these bacteria when you urinate. However, sometimes the bacteria can stick to the wall of the urethra or bladder, or grow so fast that some bacteria stay in the bladder.
Women tend to get infections more often than men because their urethra is shorter and closer to the anus. For this reason, women are more likely to get an infection after sexual intercourse or when using a diaphragm for birth control. Menopause also increases the risk for a urinary tract infection.
The following also increase your chances of developing cystitis:
A tube called a urinary catheter inserted in your bladder
Older age (especially in people who live in nursing homes)
Problems fully emptying your bladder (urinary retention)
Procedures that involve the urinary tract
Staying still (immobile) for a long period of time (for example, when you are recovering from a hip fracture
Most cases are caused by Escherichia coli (E. coli), a type of bacteria found in the intestines.
The symptoms of a bladder infection include:
Cloudy or bloody urine, which may have a foul or strong odor
Low fever (not everyone will have a fever)
Pain or burning with urination
Pressure or cramping in the lower abdomen (usually middle) or back
Strong need to urinate often, even right after the bladder has been emptied
Often in an elderly person, mental changes or confusion are the only signs of a possible urinary tract infection.
Signs and tests
A urine sample is usually collected to perform the following tests:
Urinalysis is done to look for white blood cells, red blood cells, bacteria, and to test for certain chemicals, such as nitrites in the urine. Most of the time, your doctor or nurse can diagnose an infection using a urinalysis.
Urine culture - clean catch may be done to identify the bacteria in the urine to make sure the correct antibiotic is being used for treatment.
Antibiotics taken by mouth are usually recommended because there is a risk that the infection can spread to the kidneys.
For a simple bladder infection, you will take antibiotics for 3 days (women) or 7 - 14 days (men). For a bladder infection with complications such as pregnancy or diabetes, OR a mild kidney infection, you will usually take antibiotics for 7 - 14 days.
It is important that you finish all the antibiotics, even if you feel better. People who do not finish their antibiotics may develop an infection that is harder to treat.
Your doctor may also recommend drugs to relieve the burning pain and urgent need to urinate. Phenazopyridine hydrochloride (Pyridium) is the most common of this type of drug. You will still need to take antibiotics.
Everyone with a bladder infection should drink plenty of water.
Some women have repeat or recurrent bladder infections. Your doctor may suggest several different ways of treating these.
Taking a single dose of an antibiotic after sexual contact may prevent these infections, which occur after sexual activity.
Some women may need to have a 3-day course of antibiotics at home to use for infections, based on their symptoms.
Some women may also try taking a single, daily dose of an antibiotic to prevent infections.
Over-the-counter 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 the bacterial infection is gone.
Most cases of cystitis are uncomfortable, but go away without complications after treatment.
Calling your health care provider
Call your health care provider if:
You have symptoms of cystitis
You have already been diagnosed and symptoms get worse
New symptoms develop, particularly fever, back pain, stomach pain, or vomiting
Gupta K, Hooton TM, Naber KG, et al. International clinical practice guidelines for the treatment of acute uncomplicated cystitis and pyelonephritis in women: A 2010 update by the Infectious Diseases Society of America and the European Society for Microbiology and Infectious Diseases. Clin Infect Dis. 2011 Mar;52(5):e103-20.
Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School, Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.