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Overview
The urinary system consists of the kidneys,
ureters, bladder, and urethra. The kidneys, a pair of purplish-brown
organs, are located below the ribs toward the middle of the back. The
kidneys remove liquid waste from the blood in the form of urine, keep a
stable balance of salts and other substances in the blood, and produce
erythropoietin, a hormone that aids the formation of red blood cells.
Narrow tubes called ureters carry urine from the kidneys to the bladder, a
triangle-shaped chamber in the lower abdomen. Like a balloon, the
bladder's elastic walls relax and expand to store urine and contract and
flatten when urine is emptied through the urethra. The typical adult
bladder can store about 1 1/2 cups of urine.
Adults pass about a quart and a half of urine
each day. The amount of urine varies, depending on the fluids and foods a
person consumes. The volume formed at night is about half that formed in the
daytime.
Normal urine is sterile. It contains fluids,
salts and waste products, but it is free of bacteria, viruses and fungi. The
tissues of the bladder are isolated from urine and toxic substances by a
coating that discourages bacteria from attaching and growing on the bladder
wall.
People with interstitial cystitis (IC) have an
inflamed, or irritated, bladder wall. This inflammation can lead to scarring
and stiffening of the bladder, decreased bladder capacity, glomerulations
(pinpoint bleeding) and, in rare cases, ulcers in the bladder lining.
IC, also known as painful bladder syndrome and
frequency-urgency-dysuria syndrome, is a complex, chronic disorder that has
baffled doctors for as long as it has been recognized.
Estimates of the number of people who have IC
run as high as 500,000, but no one knows for sure how many people have it.
About 90 percent of IC patients are women. While people of any age can be
affected, about two-thirds of patients are in their twenties, thirties, or
forties. IC is rare in children. In a few cases, IC has afflicted both
mother and daughter, but there is no evidence that the disorder is
hereditary, or genetically passed from parent to child.
Two Types
of IC
Because IC varies so much in its symptoms
and severity, most researchers believe that it is not one but several
diseases. Two types of IC are usually described; they are mainly
distinguished by whether ulcers have formed on the bladder wall. Most
researchers believe that IC does not generally progress from the
nonulcerative to the ulcerative form.
Nonulcerative IC - This
disorder is the most common type of IC. It usually affects young to
middle-age women who have a normal, near normal, or increased bladder
capacity when measured under general anesthesia. Glomerulations can be
seen in the bladder wall.
Ulcerative IC - This type
of IC tends to be found in middle-age to older women. Bladder capacity is
low (less than 1 1/2 cups) when measured under general anesthesia. The
decrease is thought to result in part from fibrosis, the formation of
threadlike tissue that makes the bladder stiff and small. Cracks, scars,
and Hunner's ulcers (star-shaped sores) in the bladder wall may bleed when
the bladder is filled to capacity during a cystoscopy.
Causes
No one knows what causes IC, but doctors
studying the disorder believe it is a real, physical problem-not a result,
symptom, or sign of an emotional problem.
One area of research on the cause of IC has
focused on the lining of the bladder called the glycocalyx, made up
primarily of substances called mucins and glycosaminoglycans (GAGs). This
layer normally protects the bladder wall from toxic effects of urine and its
contents. Researchers at the University of California, San Diego, found that
this protective layer of the bladder was "leaky" in about 70 percent of IC
patients they examined and may allow substances in urine to pass into the
bladder wall and trigger IC symptoms. The researchers also found that
patients with Hunner's ulcers had "leakier" bladders than patients without
the ulcers.
Some people are diagnosed with IC after taking
antibiotics for a presumed urinary tract infection. Therefore, it has been
suggested that antibiotics may damage the bladder wall and make it "leaky."
This idea has been studied carefully, but antibiotics have never been found
to harm the bladder wall. Thus, other ideas are more likely to explain why
some IC patients are diagnosed after a urinary tract infection. It is
possible that the infection started an autoimmune response against the
bladder, the patient's original symptoms were from IC all along, or an
infecting organism is in bladder cells but is not detectable through routine
tests.
What are the
signs and symptoms of the condition?
The symptoms of IC vary greatly from one
person to another but have some similarities to those of a urinary tract
infection:
As with many other illnesses, stress may also
intensify symptoms but does not cause them.
How is this
condition diagnosed?
Because the symptoms of IC are similar to
those of other disorders of the urinary system, and because there is no
definitive test to identify IC, doctors must rule out other conditions
before considering a diagnosis of IC. Among these disorders are urinary
tract or vaginal infections, bladder cancer, bladder inflammation or
infection caused by radiation to the abdomen, eosinophilic and tuberculous
cystitis, kidney stones, endometriosis, neurological disorders, sexually
transmitted diseases, low-count bacteriuria, and, in men, chronic
bacterial and abacterial prostatitis.
The diagnosis of IC in the general population
is based on
Medical tests that help identify other
conditions include a urinalysis, urine culture, cystoscopy, biopsy of the
bladder wall and, in men, laboratory examination of prostate secretions.
Urinalysis and
Urine Culture - These tests can detect and identify the most common
organisms in the urine that may be causing symptoms. There are, however,
organisms such as the bacteria chlamydia that can't be detected with these
tests, so a negative culture does not rule out all types of infection. A
urine sample is obtained either by catheterization or by the "clean catch"
method. For a "clean catch," the patient washes the genital area before
collecting urine "midstream" in a sterile container. White and red blood
cells and bacteria in the urine may indicate an infection of the urinary
tract, which can be treated with an antibiotic. If urine is sterile for
weeks or months while symptoms persist, a doctor may consider a diagnosis of
IC.
Culture of
Prostate Secretions - In men, the doctor will obtain prostatic
fluid from the patient. This fluid will be examined for signs of an
infection, which can be treated with antibiotics.
Cystoscopy
- Under Anesthesia With Bladder Distension - During cystoscopy to
diagnose IC, the doctor uses a cystoscope-an instrument made of a hollow
tube about the diameter of a drinking straw with several lenses and a
light-to see inside the bladder and urethra. The doctor will also distend or
stretch the bladder to its capacity by filling it with a liquid or gas.
Because bladder distension is painful in IC patients, before the doctor
inserts the cystoscope through the urethra into the bladder, the patient
must be given either regional or general anesthesia. These tests can detect
inflammation; a thick, stiff bladder wall; Hunner's ulcers; and
glomerulations (pinpoint bleeding) that may be seen only after the bladder
is stretched.
The doctor may also test the patient's maximum
bladder capacity, the amount of liquid or gas the bladder can hold under
anesthesia. Without anesthesia, capacity is limited by either pain or a
severe urge to urinate. Many people with IC have normal or large maximum
bladder capacities under anesthesia. However, a small bladder capacity under
anesthesia helps to support the diagnosis of IC.
Biopsy -
A biopsy is a microscopic examination of tissue. Samples of the bladder and
urethra may be removed during a cystoscopy and examined with a microscope
later. A biopsy helps rule out bladder cancer and confirm bladder wall
inflammation.
What are the
treatments?
Scientists have not yet found a cure for IC,
nor can they predict who will respond best to which treatment. Symptoms
may disappear without explanation or coincide with an event such as a
change in diet or treatment. Even when symptoms disappear, however, they
may return after days, weeks, months, or years. Scientists do not know
why.
Because doctors do not know what causes IC,
treatments are aimed at relieving symptoms. Most people are helped for
variable periods of time by one or a combination of treatments, many of
which are described briefly in this booklet. However, as researchers learn
more about IC, the list of potential treatments may change. Patients should
discuss treatment options with a doctor.
Bladder
Distension - Because some patients have noted an improvement in
symptoms after a bladder distension done to diagnose IC, the procedure is
often thought of as one of the first treatment attempts.
Researchers are not sure why distension helps,
but some believe that the procedure may increase bladder capacity and
interfere with pain signals transmitted by nerves in the bladder. Symptoms
may temporarily worsen 24 to 48 hours after distension, but should then
return to predistension levels or improve after 2 to 4 weeks.
Bladder
Instillation - This procedure may also be called a bladder wash
or bath. During a bladder instillation, the bladder is filled with a
solution that is held for varying periods of time, from a few seconds to 15
minutes, before being drained through a narrow tube called a catheter.
The only drug approved by the U.S. Food and
Drug Administration (FDA) for bladder instillation is dimethyl sulfoxide (DMSO,
RIMSO-50). With DMSO treatments a narrow tube (catheter) is guided up the
urethra into the bladder. A measured amount of DMSO is passed through the
catheter into the bladder, where it is retained for about 15 minutes before
being expelled. Treatments are given every week or two for 6 to 8 weeks, and
repeated as needed. Most people with IC who respond to DMSO notice
improvement of symptoms 3 or 4 weeks after the first 6- to 8-week cycle of
treatments. Highly motivated patients who are willing to catheterize
themselves may, after consultation with their doctor, be able to have DMSO
treatments at home. Self-administration of DMSO is less expensive and more
convenient than going to the doctor's office.
Doctors think DMSO works in several ways.
Because it passes into the bladder wall, DMSO may more effectively reach
tissue to reduce inflammation and block pain. It may also prevent muscle
contractions that may cause pain, frequency, and urgency.
A bothersome but relatively insignificant side
effect of DMSO treatments is a garlic-like taste and odor from the breath
and skin. This may last up to 72 hours after a treatment. Long-term DMSO
treatments have caused cataracts in animal studies, but this side effect has
not appeared in humans. Blood tests, including a complete blood count and
kidney and liver function tests, should be done about every 6 months.
A variety of other drugs have been used
experimentally for bladder washes, including silver nitrate, sodium
oxychlorosene (Clorpactin WCS-90), heparin, and pentosanpolysulfate (Elmiron).
Silver nitrate and oxychlorosene sodium are
thought to work by first attacking the bladder lining. This triggers the
body's immune system to step in and start the healing process. Some patients
have been successfully treated with these drugs, but the frequent, painful
treatments usually must be done under general anesthesia. Neither drug can
be used in people who have urinary reflux, a condition in which urine flows
backward up the ureters into the kidneys.
Heparin and pentosanpolysulfate are thought to
work by replacing or repairing the "leaky" bladder lining.
Oral Drugs - All drugs--even those sold over-the-counter--have side effects.
Patients should always consult a doctor before using any drug for an
extended time.
Aspirin and ibuprofen are easy to obtain and
may be a first line of defense against mild discomfort. However, they may
make symptoms worse in some patients. Over-the-counter forms of phenazopyridine hydrochloride (Azo-Standard, Prodium, and Uristat) may
provide some relief from urinary pain, urgency, frequency, and burning.
Higher doses of the drug are available by prescription as Prodium and
Pyridium.
Oxybutynin chloride (Ditropan) and a blend of
atropine, hyoscyamine, methenamine, methylene blue, phenyl salicylate and
benzoic acid (Urised) may help reduce bladder spasms that can cause
frequency, urgency, and nighttime trips to the bathroom. Urised may also
inhibit the growth of organisms in the urine.
Amitriptyline (Elavil) and doxepin (Sinequan)
act as antidepressants when given in large doses. In smaller doses, they can
help IC symptoms by blocking pain, calming bladder spasms, and decreasing
inflammation.
Some cases of IC may be caused by too much
histamine in the bladder. Antihistamine drugs such as hydroxyzine (Vistaril
and Atarax) and cimetidine (Tagamet) relieve symptoms in some IC patients.
If taken at bedtime, hydroxyzine may also help patients sleep.
Nifedipine (Procardia) is a treatment for heart
disease and high blood pressure, but it has reduced bladder pain and urgency
in some IC patients. Recent studies have suggested that heart disease
patients may have more heart or other problems if treated with nifedipine
than with other heart medications. It is not known whether these findings
would apply to IC patients without heart disease.
Pentosan polysulfate sodium (Elmiron) reduces
bladder discomfort and pain in some people with IC. Doctors don't know
exactly how the drug works, but they believe it may repair leaks in the
bladder lining. Elmiron is the first oral drug developed for IC and was
approved by FDA in the Fall of 1996.
TENS (Transcutaneous
Electrical Nerve Stimulation) - With TENS, mild electric pulses
enter the body for minutes to hours two or more times a day either through
wires placed on the lower back or the suprapubic region, between the navel
and the pubic hair, or through special devices inserted into the vagina in
women or into the rectum in men. Although scientists don't know exactly how
it works, it has been suggested that the electric pulses may increase blood
flow to the bladder, strengthen pelvic muscles that help control the
bladder, and trigger the release of hormones that block pain.
TENS is relatively inexpensive and allows the
patient to take an active part in treatment. Within some guidelines, the
patient decides when, how long, and at what intensity TENS will be used.
TENS has been most helpful in relieving pain and decreasing frequency in IC
patients who have Hunner's ulcers. Smokers do not respond as well as
nonsmokers. If TENS is going to help, change usually occurs in 3 to 4
months.
Diet -
There is no scientific evidence linking diet to IC, but some doctors and
patients believe that alcohol, tomatoes, spices, chocolate, caffeinated and
citrus beverages, and high-acid foods may contribute to bladder irritation
and inflammation. Some patients also notice a worsening of symptoms after
eating or drinking products containing artificial sweeteners. Patients may
try eliminating such products from their diet and reintroduce them one at a
time to determine which, if any, affect symptoms. It is important, however,
to maintain a well-balanced and varied diet.
Smoking - Many IC patients
feel that smoking worsens their symptoms. (Because smoking is the major
known cause of bladder cancer, one of the best things a smoker can do for
the bladder is to quit smoking.)
Exercise - Many IC patients feel that regular exercise helps relieve symptoms
and, in some cases, hastens remission.
Bladder
Training - People who have found some relief from pain may be
able to reduce frequency using bladder training techniques. Methods vary,
but basically the patient decides to void at designated times and use
relaxation techniques and distractions to help keep to the schedule.
Gradually, the patient tries to lengthen the time between the scheduled
voids. A diary of voids is usually helpful in keeping track of progress.
Surgery - This option is considered only if an IC patient has failed all
available treatments and the pain is severe. Most doctors are reluctant to
operate because the outcome is unpredictable in individual patients-some
people have surgery and still have symptoms.
Anyone considering surgery should discuss the
potential risks and benefits, side effects, and long- and short-term
complications with a surgeon and family, as well as with people who already
have had the procedure. Surgery requires anesthesia, hospitalization, and
weeks or months of recovery, and as the complexity of the procedure
increases, so do the chances for complications and failure.
To locate a surgeon experienced in performing
specific procedures, check with your doctor.
Transurethral fulguration and resection of
ulcers = Fulguration involves burning Hunner's ulcers using electricity or a
laser. When the area heals, the dead tissue and the ulcer fall off, leaving
new, healthy tissue behind. Resection involves cutting around and removing
the ulcers. Both treatments, done under anesthesia, use special instruments
inserted into the bladder through a cystoscope. Laser surgery in the urinary
tract should only be done by doctors who have the special training and
expertise needed to perform the procedure.
Denervation is a complicated procedure done by
surgeons who have special training and expertise. Rarely used in the
treatment of IC, it involves cutting some of the nerves to the bladder,
interfering with pain signals. Many approaches and techniques are used, each
of which has its own advantages and complications that should be discussed
with the surgeon.
Augmentation makes the bladder larger, most
often by adding a section of the patient's small intestine, a tube-like
structure that absorbs and transports nutrients from food for use by the
body. With this treatment, scarred, ulcerated and inflamed sections of the
patient's bladder are removed, leaving only healthy tissue and the base of
the bladder. A piece of the patient's small intestine is removed, reshaped,
and attached to what remains of the bladder. After the incisions heal, the
patient may be able to void normally.
Even in carefully selected patients-those with
small, contracted bladders-the pain, frequency, and urgency may remain or
return after surgery and the patient may have additional problems with
infections in the new bladder and difficulty absorbing nutrients from the
shortened intestine. Some patients are incontinent while others cannot void
at all and must insert a catheter into the urethra to empty urine from the
bladder.
Bladder Removal (Cystectomy) - Different methods
can be used to reroute urine once the bladder has been removed. In most
cases, the ureters are attached to a piece of bowel that opens onto the skin
of the abdomen, called a stoma. Urine empties through the stoma into a bag
outside the body. This procedure is called a urostomy. Some urologists are
using a technique that also requires a stoma but allows urine to be stored
in a pouch inside the abdomen. At intervals throughout the day, the patient
puts a catheter into the stoma and empties the pouch. Patients with either
type of urostomy must use very clean, or sterile, steps to prevent
infections in and around the stoma.
With a third method, a new bladder is made from
a piece of the patient's bowel (large intestine) and attached to the urethra
in place of the removed bladder. After a time of healing, the patient may be
able to empty the bladder by voiding at scheduled times or may insert a
catheter into the urethra. Few surgeons have the special training and
expertise needed to perform this procedure.
Even after total bladder removal, some patients
still experience variable symptoms of IC. Therefore, the decision to undergo
a cystectomy should only be undertaken after serious deliberation on the
potential outcome.
Electrical Nerve Stimulation - This surgical
treatment is a variation of TENS, described previously, but involves
permanent implantation of electrodes and a unit that emits continuous
electrical pulses. This relatively new procedure has variable short-term
results, unknown long-term effects and, therefore, is not widely used.
Special Concerns
Cancer - There is no evidence
that IC increases the risk of bladder cancer. However, the long-term effects
of IC require further observation and research.
Pregnancy - Researchers have
little information about pregnancy and IC, but believe that the disorder
does not affect fertility or the health of the fetus. Some women have a
remission from IC during pregnancy, while others have more pain and pressure
during the third trimester, possibly due to the weight of the fetus on the
bladder.
Working - Symptom flare-ups
that result in frequent absences from work may make it difficult to get or
keep a job. The Social Security Administration provides information on
Social Security Disability benefits. The National Organization of Social
Security Claimants' Representatives can refer you to a lawyer experienced
with Social Security claims. (See "Other Resources.")
Coping - The emotional support
of family, friends, and other people with IC is very important in helping
patients cope with the disorder. Studies have found that IC patients who
learn about the disorder and become involved in their own care do better
than patients who do not. The Interstitial Cystitis Association can provide
the address and phone number of the nearest support group. (See "Other
Resources.")
Other coping tips:
Research
Although answers may seem slow in coming,
researchers are working every day to solve the painful riddle of IC. Some
scientists receive funds from the Federal Government to help support their
research, and some receive support from other sources such as their
employing institution, drug companies, and the Interstitial Cystitis
Association. Researchers and doctors around the country, regardless of who
funds their work, may competently diagnose and treat IC.
The National Institute of Diabetes and
Digestive and Kidney Diseases (NIDDK), a part of the National Institutes of
Health (NIH), leads the Federal Government's research efforts on IC. Most
studies funded by the NIDDK are a result of unsolicited grant applications
sent to NIH by scientists at universities and medical centers throughout the
United States. Other NIDDK-funded studies result from solicitations issued
to encourage increased research on a certain topic.
By law, all applications sent to NIH are first
reviewed by non-Government experts in the field of the proposed research for
scientific merit and feasibility before being reviewed by the NIDDK's
National Advisory Council. The council is made up of non-Government
scientists, health professionals, and individuals who represent voluntary
groups with an interest in the research of the institute. Approved
applications are eligible for funding based on a scientific merit rating, or
priority score, assigned by the initial reviewers. Applications are usually
funded in priority score order, with the best applications funded first.
The NIDDK's investment in scientifically
meritorious IC research has grown considerably since 1987, largely due to
special solicitations. We now support research across the country that is
looking at various aspects of IC, such as how urine contents may injure the
bladder and what possible role organisms identified using nonstandard
methods may have in causing IC. In addition to funding research, NIDDK
sponsors scientific workshops where investigators share the results of their
studies and discuss future areas for investigation.
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