Featured Article On Ankylosing Spondylitis
An Updated Overview Of Spondyloarthritis:
A Family Of Related Diseases
Similarities And Differences Between Six Conditions - A Q&A
With Dr. Jessica Walsh
Spring 2013 Issue of Spondylitis Plus
Q: We hear a few
different terms to
spondylitis (AS) and
spondyloarthropathy. . . Is
there a difference?
Spondyloarthritis and spondyloarthropathy
are often used interchangeably. Some experts
prefer the term spondyloarthritis rather than
spondyloarthropathy because the ending "arthritis" indicates
inflammation of the joint, whereas the ending "arthropathy"
can refer to any type of joint disease. Inflammation is a key
feature that helps distinguish spondyloarthritis from other
types of arthritis, including wear-and-tear arthritis, such as
osteoarthritis. Spondyloarthritides is the plural form of
Q: How is this group of diseases related? Why is it
sometimes called a "family" of conditions?
These diseases look and behave in similar ways because they
share overlapping disease features. Common features of
spondyloarthritis include inflammation in the spine, pelvis,
other joints, intestine, eyes [Editor's note: please see side bar
on Uveitis / Iritis to the right], and heels. This family of
diseases is divided into individual categories according to
the predominant disease feature(s).
For example, inflammation
of the intestine can occur
with any type of
spondyloarthritis, but is
most pronounced in
patients with IBDassociated
called enteropathic arthritis).
Q: What does "seronegative" mean? How does it relate
to this group of diseases?
Seronegative means that specific blood tests used to help
diagnose rheumatoid arthritis are negative. In some
instances, these blood tests are helpful in determining
whether a person has rheumatoid arthritis or
spondyloarthritis. In most cases, a diagnosis of
spondyloarthritis can be made without these blood tests.
Q: Is ankylosing spondylitis (AS) considered the
"primary" disease? Why or why not?
For people with ankylosing spondylitis, it is the primary
disease. For people with other types of spondyloarthritis, it
In the past, ankylosing spondylitis has been portrayed as the
primary type of spondyloarthritis for several reasons
including the following:
- Ankylosing spondylitis is easier to study than reactive
arthritis and IBD-associated arthritis because it is much
- Ankylosing spondylitis is often easier for doctors and
patients to recognize than undifferentiated spondyloarthritis
and reactive arthritis.
- Ankylosing spondylitis has been recognized as a unique
type of arthritis for hundreds of years, whereas other types
of spondyloarthritis were described more recently. For
example, psoriatic arthritis was not widely recognized as
a distinct form of arthritis until the 1960s.
Q: Can you give us a key symptom or "feature" of each
of the conditions in this group? What makes each one
distinct or different from the others?
Ankylosing Spondylitis (AS):
Inflammation in the pelvis and/or spine causes inflammatory
back pain. Inflammatory back pain usually starts gradually
before the age of 40, tends to improve with activity but not
rest, and occurs with stiffness in the morning that lasts at
least 30 minutes.
Reactive Arthritis (Reiter's Syndrome - ReA):
An infection in the intestine or urinary tract usually occurs
before inflammation in the joints.
Juvenile Spondyloarthritis (JSpA):
Symptoms begin in childhood. JSpA can look like any other
type of spondyloarthritis. Enthesitis (inflammation where
tendons or ligaments meet bone) is often a dominant disease
Arthritis Associated With Inflammatory Bowel Disease
(Enteropathic Arthritis - EnA):
Inflammation of the intestine is a predominant feature.
Symptoms may include chronic diarrhea, abdominal pain,
weight loss, and/or blood in the stool. The most common
types of inflammatory bowel disease are Crohn's,
ulcerative colitis, and undifferentiated colitis.
Psoriatic Arthritis (PsA):
PsA frequently causes pain and swelling in the small joints
of the hands and feet. Most people with PsA have a
psoriasis skin rash. Some people have a "sausage digit"
with a toe or finger that swells between the joints as well
as around the joints.
Undifferentiated Spondyloarthritis (USpA):
People with USpA have symptoms and disease features
consistent with spondyloarthritis, but their disease doesn't
fit into another category of spondyloarthritis. For
example, an adult may have iritis, heel pain (caused by
enthesitis), and knee swelling, WITHOUT back pain,
psoriasis, a recent infection, or intestinal symptoms. This
person's combination of disease features suggests
spondyloarthritis, but he or she doesn't fit into the
categories of ankylosing spondylitis, psoriatic arthritis,
reactive arthritis, juvenile spondyloarthritis or IBD-associated
Q: Can one of these conditions share symptoms or
complications with another one of the conditions? In
general terms, do symptoms overlap? If so, how? What
are the main similarities - if any?
Absolutely. The main similarities that can occur with any
type of spondyloarthritis are:
- Inflammation in the pelvis and spine that usually causes
inflammatory back pain.
- Pain and/or swelling of any other joint in the body (hips,
knees, ankles, feet, hands, wrists, elbows, shoulders etc.)
- Sudden onset of marked pain and redness in one eye at a
- Psoriasis skin rash.
- Inflammation in the intestine (Crohn's, ulcerative colitis,
- Inflammation along the tendons of the finger or toes
(sausage digits, also called dactylitis).
- Inflammation where tendons and ligaments meet the
bone (enthesitis). This commonly occurs at the back or
bottom of the heel.
Q: Why would a doctor diagnose one form of
spondyloarthritis over another?
Doctors classify people as having a certain type of
spondyloarthritis according to the predominant disease
feature(s). For example, a person with psoriasis and joint
swelling in the hands and feet will most likely be
classified as having psoriatic arthritis. A person with
inflammatory back pain and x-ray changes consistent with
inflammation in the sacroiliac joints in the pelvis will
likely be classified as having ankylosing spondylitis. A
person with Crohn's and swelling in the knees and ankles
most likely has IBD-associated arthritis. Sometimes,
disease features are equally dominant and a person may fit
into more than one type of spondyloarthritis. For
example, a person could have psoriasis, inflammation in
the pelvis/spine, and Crohn's disease. This person could
correctly be said to have any of the following:
- Psoriatic arthritis with ankylosing spondylitis and
- Ankylosing spondylitis with psoriasis and Crohn's.
- IBD-associated arthritis with ankylosing spondylitis
Q: Can a diagnosis change from, say, undifferentiated
spondyloarthritis (USpA) to ankylosing spondylitis or
another one of these conditions? Why would this
Yes. The diseases can evolve or change over time, since
not all symptoms occur at once. For example, the
previously discussed person with USpA with iritis,
enthesitis, and knee swelling could develop back pain and
inflammatory changes on x-rays that would lead to the
diagnosis of ankylosing spondylitis.
Q: Are men and women affected at different rates
between these diseases? Can you give us some details
on how these rates were determined?
Similar numbers of men and women are affected with
spondyloarthritis. In the past, it was thought that
ankylosing spondylitis was more common in men than
women. More recent studies suggest that ankylosing
spondylitis occurs in similar numbers of men and women.
Early estimates of the occurence of ankylosing spondylitis
suggested that ankylosing spondylitis occurred 9-10 times
more frequently in men than women. However, there were
problems with how these early studies were done. More
recent studies reported that men are 2 to 3 times more likely
than women to have ankylosing spondylitis. These studies
use relatively narrow definitions of ankylosing spondylitis
that rely on classic manifestations of inflammatory back pain
and damage on x-rays. Classic inflammatory back pain may
be the initial symptom in men more frequently than in
women, and women may have less x-ray damage than men.
Despite these differences, the overall disease severity is
similar in men and women.
When broader definitions are used to identify people with
spondyloarthritis in the pelvis and/or spine (axial
spondyloarthritis), the prevalence is similar in men and
Q: How are these conditions treated? Are there any
notable differences in treatment such as prescribed
There are several treatment options for various types of
spondyloarthritis. The treatments for each disease overlap,
but they are not identical. For example, certain treatments
may simultaneously help with psoriasis, inflammatory bowel
disease, enthesitis, and arthritis. Other treatments may help
with one or two disease features, but not the others. There
are even some treatments that may help with one disease
feature, but make another feature worse. Treatments need to
be tailored for each individual, according to the type and
severity of specific disease features. Many other factors must
also be considered when selecting therapies, including other
medical conditions, access to therapies, and the preferences
of patients. [Editor's note: Please see the medications table on
page 10 for a list of commonly used medications to treat
Q: Is there a known cause for these diseases?
We know that there are several specific genes that increase
the risk of developing spondyloarthritis. HLA-B27 is the
best studied gene and it associates most strongly with
inflammation in the pelvis (sacroiliac joints) and spine.
Most people with HLA-B27 and other high risk genes never
develop spondyloarthritis. We don't yet understand why
some people develop disease and others don't. There are also
studies suggesting that things in our environment may cause
disease. For example, specific types of infections may trigger
disease. However, environmental triggers are not known for
most people who develop spondyloarthritis. There is much
research that needs to be done to better understand why
certain people get these diseases.
Q: Is there a cure?
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