Spondyloarthritis is the term for several inflammatory diseases that cause different types of arthritis. These diseases affect the joints and entheses, which are where ligaments and tendons attach to the bone.
Spondyloarthritis (SpA) mainly occurs in the spine and pelvic area. Doctors classify SpA in this area as axial spondyloarthritis (AS).
When the inflammation affects the limbs or other areas, such as the eyes and digestive tract, doctors call it peripheral spondyloarthritis.
In this article, we explain the different types of SpA, their effects, and different ways to manage and treat symptoms.
Doctors classify the type of SpA by its location in the body and the type of tissue it affects.
Ankylosing spondylitis (AS) is the most common form of SpA. A 2019 study estimated that AS develops in 0.2–1% of the United States population. However, the study authors concede that estimates vary significantly between different studies.
Symptoms include pain and stiffness in the spine and the area between the spine and the pelvis.
The above study also suggests that in 2016 over 47% of people with AS were female.
Reactive arthritis (ReA)
Previously called Reiter’s syndrome, ReA symptoms occur when the immune system reacts to specific bacterial infections of the intestinal, genital, or urinary tract.
ReA can affect the following areas:
- the joints
- the eyes
- the urethra
- the skin
ReA inflammatory activity can result in:
- destroyed cartilage
- impairment to thought processes and cognition
- eye inflammation and redness
- joint pain and inflammation
ReA can also result in back pain, typically in the sacroiliac joints. According to the American College of Rheumatology (ACR), ReA mostly occurs in men between 20–50 years of age.
Enteropathic arthritis (EnA)
This type causes inflammation in some areas of the digestive tract. It is a form of inflammatory arthritis with links to inflammatory bowel disease (IBD), a group of diseases that includes Crohn’s disease and ulcerative colitis. The symptoms of EnA are similar.
According to the Spondylitis Association of America, around 1 in 5 people with this type of reactive arthritis experience inflammation in the joints of the limbs. However, for 1 in 6 people, it can adversely affect the entire spine.
Stomach pain and bloody diarrhea are other common symptoms.
Psoriatic arthritis (PsA)
This type of SpA affects people who have psoriasis, an immune-modulated, inflammatory skin disease that causes patches of red, flaky, and scaly skin.
PsA may develop in up to 30% of people with psoriasis. In some cases, PsA can occur before the expression of the skin disease.
Symptoms include joint pain, stiffness, and swelling in the spine, fingers, and feet. Other effects include:
- a reduced range of motion in the joints
- skin lesions that occur due to underlying psoriasis
- conjunctivitis in 30% of those with PsA
- iritis in 7% of people with PsA
Juvenile spondyloarthritis (JSpA)
Also known as juvenile spondyloarthropathy, JSpA is a group of rheumatic diseases that first present in those under 16 years of age.
Symptoms usually affect the joints of the lower body, including the hips, knees, and feet, but can occur in other places, such as the eyes, skin, bowels, and spine.
Forms of JSpA can include juvenile AS, PS, ReA, and EnA, along with undifferentiated spondyloarthritis (USpA).
A doctor may diagnose USpA if someone displays some symptoms of spondyloarthritis but does not meet the full criteria for any of the above conditions.
Some people may eventually develop more symptoms that enable the doctor to diagnose symptoms more accurately.
Signs and symptoms of SpA depend on the type. However, symptoms usually present in two distinct ways:
- Inflammation and pain: These are defining characteristics of SpA. It may begin in the spine, but it can also affect the pelvis, hands, feet, arms, and legs. The inflammation causes pain and stiffness.
- Bone damage: Destruction of the bone may occur. This damage can eventually lead to spinal deformities, which may impact mobility.
Along with inflammation, pain, and bone damage, people with SpA may experience:
The American College of Rheumatology (ACR) advise that researchers have found up to 30 genes that may cause AS, the most common form of SpA.
The most significant gene behind SpA is called HLA-B27. This gene may play a role in the other forms of spondyloarthropathies and, in some instances, can assist doctors with diagnosing these cases.
People who carry HLA-B27 have a higher risk of developing AS than those without it, although not everyone with the gene develops the condition. Similarly, not everyone with AS carries the HLA-B27 gene.
According to the Canadian Spondylitis Association, approximately 10% of people with SpA do not have the HLA-B27 gene.
It is often unclear what causes the expression of SpA. However, certain factors may increase a person’s risk for specific types of SpA, including:
- carrying the HLA-B27 gene
- bacterial infections
- having IBD or psoriasis
- having a family member with SpA
- being of Siberian Eskimo, Alaskan, or Scandinavian Lapps descent
As no cure is currently available for SpA, treatment involves managing symptoms, limiting the spread of the disease to different bodily systems or areas, and reducing the risk of complications.
The treatment regimen will depend on the needs of the individual and the type of SpA they have. Treatment options include medication, surgery, and physical therapy.
Emotional support can also improve quality of life, as SpA can affect psychological and physical well-being.
There are several medications available to treat the symptoms of SpA, including:
- nonsteroidal anti-inflammatory drugs (NSAIDs), including ibuprofen, naproxen, meloxicam, and indomethacin
- corticosteroid injections into the joint or the membrane of the tendon showing SpA symptoms
- disease-modifying antirheumatic drugs (DMARDs) for people who do not respond to corticosteroid injections and NSAIDs
- antibiotics for those with ReA
Doctors do not recommend oral corticosteroids for people with SpA, as a person would require a high dose that can cause adverse effects.
Most recently, the U.S. Food and Drug Administration (FDA) approved the following biologic drugs for people with SpA:
- infliximab (Remicade), which a person would receive through an intravenous (IV) infusion every 6–8 weeks
- etanercept (Enbrel), which a person would receive once every week as a 50-milligram (mg) injection
- adalimumab (Humira), which takes the form of a 40-mg injection every 2 weeks
- certolizumab (Cimzla), which a person receives as a 200-mg injection every 2 weeks or a 400-mg injection every 4 weeks
- golimumab (Simponi), a monthly injection of 50 mg
- secukinumab (Cosentyx), which people receive as a 150-mg injection every 4 weeks after 5 weekly doses to start the course
Biologics work to modify a person’s immune response and reduce inflammation. However, they can be expensive and cause significant side effects, such as an increased risk of severe infections.
It may be best to ask a doctor about the risks and benefits, as well as alternatives, before choosing to take a course of biologics.
Some people with SpA may benefit from surgery.
For example, if significant pain or disability results from cartilage destruction in the hip, replacing the hip with a prosthesis may provide health benefits and improve a person’s quality of life.
Surgery on the spine is usually not necessary for individuals with SpA. However, doctors may perform surgery on those with broken bones or deformities of the neck that leave the person unable to straighten their neck.
Regular physical activity helps to improve or maintain mobility.
A qualified physical therapist can design a suitable program of exercises and stretches for those with SpA.
SpA can have an emotional impact as well as a physical one.
People with the condition may find it useful to attend psychological counseling or to take part in a support group for people with chronic conditions.
As the cause of SpA is not clear and is likely to have a genetic component, preventing its onset is difficult.
However, early diagnosis and intervention can limit the progression of the disease and its symptoms. Listed below are some factors to consider:
Leading a healthful lifestyle can go a long way to easing the symptoms of SpA. Important lifestyle factors include:
Eating a healthful, balanced diet is important for overall health and maintaining a healthy body weight. Being overweight puts additional stress on the joints.
Foods to eat include:
- whole grains
- nuts and seeds
- lean protein, such as beans, lentils, and lean meats
- fatty fish
Regular physical activity is important in the management of SpA. It helps to relieve pain and stiffness and can help a person stay active and mobile.
Low-impact exercises, such as walking, swimming, and using an elliptical trainer, are best for people with SpA. They put less pressure on the joints than high-impact activities.
Smoking contributes to inflammation and can make the symptoms of SpA worse.
SpA is a progressive disease with no known cure.
Nevertheless, once a person takes steps to manage the condition and limit its progression, the outlook for the majority of people with SpA is good.
They can go on to live full lives with a low risk of further complications.