Urinary tract infection (cystitis)

Urinary tract infection (cystitis)

Definition:

Cystitis is an inflammation of the urinary bladder or urethra. In most cases, cystitis is caused by a bacterial infection and is commonly referred to as a "urinary tract infection."

Alternative Names:

Bladder infection; UTI

Causes, incidence, and risk factors:

Cystitis is usually caused when bacteria enter the urethra and bladder and cause inflammation and infection. It is a very common condition. After infancy, urinary tract infections occur more often in females because their urethra is shorter and closer to the anus.

During childhood, about 1% of boys and up to 5% of girls will develop urinary tract infections. In boys the peak age is before the first birthday. Urinary tract infections are much more common among uncircumcised boys. In girls, the peak age for first infections is 3 years, overlapping with the toilet training period.

Because cystitis in children can be promoted by abnormalities in the urinary tract, children with cystitis (especially those under age 5) deserve special follow-up to prevent later kidney damage.

Older adults are at high risk for developing cystitis, with the incidence in the elderly being as high as 33 out of 100 people.

Over 90% of cases of cystitis are caused by E. coli, a bacterium normally found in the intestine. Normally, the urethra and bladder have no bacteria. Bacteria that manage to enter the bladder are usually removed during urination. But if bacteria remain in the bladder, they grow easily and quickly and result in infection.

The risk of cystitis is higher when the bladder or urethra becomes blocked, and the flow of urine stops. It can also occur when instruments are inserted into the urinary tract (such as during catheterization or cystoscopy). Other risks include pregnancy, diabetes, and a history of analgesic nephropathy or reflux nephropathy.

Sexual intercourse can increase the risk of urinary tract infections in women because bacteria can be introduced into the bladder through the urethra.

The elderly population are at increased risk for developing urinary tract infections due to incomplete emptying of the bladder associated with such conditions as benign prostatic hyperplasia (BPH), prostatitis, and urethral strictures.

Also, lack of adequate fluids, bowel incontinence, immobility or decreased mobility, indwelling urinary catheters and placement in a nursing home, all place the person at increased risk for developing cystitis.

Related disorders include:

Cystitis - acute bacterial
Cystitis - noninfectious (acute urethral syndrome)
Cystitis - recurrent (repeated bladder infections)
Urinary tract infection - chronic or recurrent
Urinary tract infection - complicated (pyelonephritis)
Vesicoureteral reflux

Symptoms:

Pressure in the lower pelvis
Urination, painful (dysuria)
Frequent need to urinate (frequency)
Urgent need to urinate (urgency)
Need to urinate at night
Abnormal urine color (cloudy urine)
Blood in the urine (hematuria)
Foul or strong urine odor
Young children with urinary tract infections may only have a fever, or even no symptoms at all.

Additional symptoms that may be associated with this disease:

Sexual intercourse, painful
Penis pain
Flank pain
Fatigue
Fever
Chills
Vomiting
Mental changes or confusion (Note: in elderly people, mental changes or confusion often are the only signs of a possible urinary tract infection.)

Signs and tests:

Tests generally include taking a urine sample:

A urinalysis commonly reveals white blood cells (WBC) or red blood cells (see also RBC - urine).
A urine culture (clean catch) or catheterized urine specimen may be performed to determine the type of bacteria in the urine and the appropriate antibiotic for treatment.

TESTING IN CHILDREN
Because many children with cystitis have urinary tracts that predispose them to infections, because these infections are usually preventable, and because the long-term consequences of repeated urinary tract infections in children can be severe, many children with cystitis need special imaging studies to determine why they got their urinary tract infections.

These studies usually include both an ultrasound of the kidneys and an x-ray taken during urination (called a voiding cystourethrogram or VCUG).

Most experts recommend this evaluation for:

Girls over age 5 with 2 or more urinary tract infections
All boys with their first urinary tract infection
All children with a fever with their urinary tract infection
All children under age 5 with their first urinary tract infection

For a girl's first urinary tract infection, recommendations vary on when a complete evaluation is necessary.

In young girls, recurrent urinary tract infections may be an indication of a urinary tract abnormality, such as ureterovesical reflux, and should be evaluated by a medical care provider.

In boys, a single urinary tract infection indicates the necessity for evaluation, because urinary tract infections in boys are extremely uncommon in the absence of urinary tract abnormalities.

Treatment:

Mild cases of acute cystitis may disappear spontaneously without treatment. However, because of the risk of the infection spreading to the kidneys (complicated UTI), treatment is usually recommended. In children, acute cystitis should be treated promptly with antibiotics to protect their developing kidneys. Also, due to the high mortality rate in the elderly population, prompt treatment is recommended.

MEDICATIONS:
Antibiotics may be used to control the bacterial infection. It is imperative that you finish the entire course of prescribed antibiotics. Commonly used antibiotics include:

Nitrofurantoin
Cephalosporins
Sulfa drugs (sulfonamides)
Amoxicillin
Trimethoprim-sulfamethoxazole
Doxycycline (should not be used under age 8)
Quinolones (should not be used in children)

Chronic or recurrent UTI should be treated thoroughly because of the chance of kidney infection (pyelonephritis). Antibiotics control the bacterial infection. They may need to be given for long periods of time (as long as 6 months to 2 years), or stronger antibiotics may be needed than for single, acute episodes of cystitis. Prophylactic low-dose antibiotics may be recommended after acute symptoms have subsided.

Phenazopyridine hydrochloride (pyridium) may be used to reduce the burning and urgency associated with cystitis. In addition, acidifying medications, such a ascorbic acid may be recommended to decrease the concentration of bacteria in the urine.

SURGERY:
Surgery is generally not indicated in the presence of a urinary tract infection.

OTHER THERAPY:
Preventive measures may reduce symptoms and prevent recurrence of infection. Keeping the genital area clean and remembering to wipe from front to back may reduce the chance of dragging E. coli bacteria from the rectal area to the urethra.

Urinating immediately after sexual intercourse may help eliminate any bacteria that may have been introduced during intercourse. Refraining from urinating for a long period of time may allow bacteria time to multiply, so frequent urination may reduce the risk of cystitis in those who are prone to urinary tract infections.

DIET:
Increasing the intake of fluids encourages frequent urination that flushes the bacteria from the bladder. Avoid fluids that irritate the bladder, such as alcohol, citrus juices, and caffeine.

MONITORING:
Follow-up may include urine cultures to ensure that bacteria are no longer present in the bladder.

Expectations (prognosis):

Cystitis is uncomfortable, but usually responds well to treatment.

Complications:

Chronic or recurrent urinary tract infection
Complicated UTI
Pyelonephritis (kidney infection)

Calling your health care provider:

Call for an appointment with your health care provider if symptoms indicate cystitis may be present.

If you have cystitis, call if symptoms worsen, or new symptoms develop (especially fever, back or flank pain, and vomiting).

Prevention:

Appropriate hygiene and cleanliness of the genital area may help reduce the chances of introducing bacteria through the urethra. The genitals should be cleaned and wiped from front to back to reduce the chance of dragging E. coli bacteria from the rectal area to the urethra.

For those who are prone to urinary tract infections, it may help to drink plenty of fluids, because frequent urination flushes bacteria out the bladder. Urinating immediately after sexual intercourse may help flush out bacteria that may have been introduced with intercourse.

Review Date: 3/3/2002
Reviewed By: Alan Greene, M.D., F.A.A.P., Chief Medical Officer, A.D.A.M.; Clinical Assistant Professor, Department of Pediatrics, Stanford University School of Medicine; Attending Physician, Packard Children's Hospital at Stanford (3/3/2002). Previously reviewed by Jeffrey Heit, M.D., Department of Internal Medicine, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network (8/24/2001).

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2003 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.