Juvenile Spondyloarthritis

Juvenile Spondyloarthritis is a group of childhood inflammatory diseases that cause arthritis before age 16, primarily affecting joints in the lower body, the spine, and sites where tendons attach to bones. While managing this condition can be challenging, with proper treatment and lifestyle adjustments, children can lead active, fulfilling lives.

Table of contents

• What is Juvenile Spondyloarthritis?
• Types of Juvenile Spondyloarthritis
• What Causes This Condition?
• Signs and Symptoms
• Areas of the Body Affected
• Who Gets Juvenile Spondyloarthritis?
• How Is It Diagnosed?
• Treatment Options
• Living Well with Juvenile Spondyloarthritis

What is Juvenile Spondyloarthritis?

Juvenile Spondyloarthritis (JSpA), also known as Juvenile Spondyloarthropathy, is a medical term for a group of childhood rheumatic diseases that cause arthritis (joint inflammation) before the age of 16 and may continue through adult life^[1]. The condition is considered a distinct subtype of juvenile arthritis and represents one of the most common forms of chronic arthritis in childhood^[3].

Juvenile Spondyloarthritis is an umbrella term for a group of inflammatory diseases that primarily involve the spine, joints, and entheses — the places where tendons and ligaments attach to bones^[3]. The term “spondyl” means spine, while “arthritis” refers to joint inflammation. These conditions typically cause pain and inflammation in joints in the lower part of the body, such as the pelvis, hips, knees, and ankles^[1].

This group of diseases is characterized by several common features, including inflammation of the spine (known as sacroiliitis and spondylitis), asymmetric peripheral arthritis, enthesitis, and sometimes painful eye inflammation^[5]. Unlike some other forms of arthritis, these conditions tend to affect boys more frequently than girls and typically have a later onset in childhood^[3].

Types of Juvenile Spondyloarthritis

Juvenile Spondyloarthritis includes several different conditions that share similar features. The juvenile spondyloarthropathies include^[1]:

• Enthesitis-related arthritis (ERA) — the most common form in children, accounting for about 10 to 40 percent of all juvenile arthritis cases^[3]
• Undifferentiated spondyloarthritis — when the condition doesn’t fit clearly into one specific category
• Juvenile ankylosing spondylitis (JAS) — specifically involves the spine and occurs when imaging studies show spinal involvement^[2]
• Psoriatic arthritis — arthritis associated with the skin condition psoriasis, representing about 2 to 10 percent of juvenile arthritis cases^[3]
• Reactive arthritis — arthritis that develops following certain infections
• Arthritis associated with inflammatory bowel disease (also called enteropathic arthritis) — arthritis occurring with conditions like Crohn’s disease or ulcerative colitis

It’s important to understand that these names may overlap from a clinical and therapeutic point of view, and the specific classification can sometimes vary^[6].

What Causes This Condition?

The exact cause of Juvenile Spondyloarthritis is not fully understood. However, researchers know that genetics plays a significant role^[2]. The disease tends to run in families and is strongly associated with a gene called HLA-B27.

About 60 to 90 percent of patients with arthritis affecting the spine will test positive for the HLA-B27 gene^[2]. In fact, about 80 to 90 percent of children with juvenile ankylosing spondylitis have this gene marker^[4]. HLA-B27 is a protein located on the surface of immune cells^[6].

However, having the HLA-B27 gene doesn’t mean someone will definitely develop the condition. Remarkably, only a small fraction of people with HLA-B27 ever develop arthritis^[6]. Researchers believe the disease is triggered when children with the gene are exposed to a virus, bacteria, or other outside factors^[4]. In some cases, the onset of arthritis is preceded by gastrointestinal or urogenital infection, which is known as reactive arthritis^[6].

Juvenile Spondyloarthritis is considered a multifactorial condition, meaning that many factors are involved in causing it. These factors are usually both genetic and environmental, requiring a combination of genes from both parents plus unknown environmental factors to produce the condition^[12].

Signs and Symptoms

The symptoms of Juvenile Spondyloarthritis can vary from child to child and sometimes appear episodic and unpredictable, seeming to come and go without an obvious cause over long periods of time^[1]. Symptoms usually develop slowly over several weeks or months^[4].

Common symptoms include^[4][10]:

• Pain, swelling, redness, and warmth in joints, particularly in the toes, heels, ankles, buttocks, knees, rib cage, upper spine, shoulders, and neck
• Back pain during the night or early morning
• Pain in the low back and buttocks
• Stiffness in the morning or after long periods of inactivity
• Pain and tenderness where tendons or ligaments attach to bones (enthesitis)
• Fatigue and lethargy
• Mild fever
• Loss of appetite and weight loss
• Stooped posture, which may develop as a response to back pain
• Shortness of breath if the rib cage is affected

Pain from enthesitis commonly occurs at specific sites^[2]:

• The heel
• Top and bottom of the kneecap (patella)
• Ball of the foot
• Bottom of the foot at the heel
• Mid-foot zone

At first, symptoms may mirror enthesitis-related arthritis, with pain felt in the hips, knees, or heels first, followed by pain in the low back and buttocks^[4].

Areas of the Body Affected

Juvenile Spondyloarthritis typically causes pain and inflammation in the joints in the lower part of the body, such as the pelvis, hips, knees, and ankles^[1]. However, other areas of the body can also be affected.

Spine and Back: The condition can cause inflammation of the spine and the sacroiliac joint (where the pelvis and spine meet)^[4]. Over time, the joints and bones of the spine may grow together, or fuse, causing the spine to become stiff and hard to move^[4].

Large Joints: When arthritis affects large joints such as the hip or spine, the swelling can be hard to see or not visible at all on physical examination. This means imaging such as ultrasound, CT scan, or MRI is needed to properly evaluate the joint^[2].

Eyes: Eye involvement is common and can cause dryness, pain, redness, sensitivity to light, and trouble seeing due to chronic eye inflammation called uveitis or iritis^[4].

Digestive Tract: Chronic inflammation may lead to inflammatory bowel disease, causing abdominal pain and diarrhea^[4]. Many children with juvenile ankylosing spondylitis also have intestinal inflammation or inflammatory bowel disease^[10].

Rib Cage: The rib cage may also fuse, making it hard to breathe^[4].

Skin and Bowels: Other areas such as the skin and bowels can be affected as well^[1].

Who Gets Juvenile Spondyloarthritis?

Juvenile Spondyloarthritis is characterized by male predominance and later onset in childhood^[3]. The condition affects boys and men two to three times more often than girls and women^[4][12].

In children, the average age of diagnosis is 10 to 13 years of age^[2], though it can start in the teens and twenties^[12]. In most cases, the first symptoms appear around the age of 6 years^[6].

Juvenile Spondyloarthritis affects people all around the world^[2]. While the exact number of people with the condition is not fully known, it occurs in about 5 to 9 out of 1,000 people^[2]. Juvenile arthritis is one of the most common rheumatologic diseases among children, with prevalence estimates ranging from 1 to 4 per 1,000 children, similar to that of Type I diabetes^[5].

Depending on the region of the world, Juvenile Spondyloarthritis can account for about 30 percent of children with chronic arthritis^[6]. A great proportion of patients — up to 85 percent — with juvenile spondyloarthritis are positive for the HLA-B27 gene^[6].

How Is It Diagnosed?

Diagnosing Juvenile Spondyloarthritis can be challenging because spine involvement may not occur until years after other symptoms begin^[4]. However, it’s important to see a doctor as soon as joint pain begins.

A primary care doctor may be the first person you see, but they may refer you to a doctor who specializes in treating inflammatory arthritis, called a rheumatologist^[4]. There is no single test to diagnose Juvenile Spondyloarthritis^[4].

The diagnosis process typically includes:

Medical History: The doctor will ask about symptoms, when they started, if they come and go, and whether there is a family history of similar conditions^[4].

Physical Examination: The healthcare provider will perform a physical exam to check for joint swelling, tenderness, and mobility issues^[4].

Laboratory Tests: Various blood tests may be ordered to rule out other causes of joint pain. These may include^[10][12]:

• Testing for the HLA-B27 gene marker
• Erythrocyte sedimentation rate (ESR or sed rate) to measure inflammation
• General blood tests

Imaging Studies: Because swelling in large joints and the spine can be hard to see on physical examination, imaging tests are often needed. These may include^[2][10]:

• X-rays to show changes in the spine and joints (though changes may not show up in early stages)
• MRI (Magnetic Resonance Imaging) to create more detailed images
• Ultrasound
• CT scan

Treatment Options

A common treatment regimen for Juvenile Spondyloarthritis involves medication, exercise, physical therapy, good posture practices, and other options such as applying heat or cold to help relax muscles and reduce joint pain^[11].

Medications: Several types of medications may be used to manage symptoms and slow disease progression. These include^[9][11]:

• Nonsteroidal anti-inflammatory drugs (NSAIDs) to reduce pain and inflammation
• Corticosteroids for short-term use to control inflammation
• Disease-modifying antirheumatic drugs (DMARDs) to slow disease progression
• Biologic medications, particularly TNF inhibitors, which may be introduced depending on disease activity and prognostic factors

The concept of a disease continuum suggests that medications shown to be safe and effective in treating adult spondyloarthritis may also be beneficial for children^[9].

Physical Therapy and Exercise: Physical therapy and regular exercise are essential components of treatment^[11]. Exercise helps maintain proper posture, preserve spine flexibility, and relieve pain. Swimming and other exercises that extend the back, such as Pilates, yoga, and tai chi, are particularly beneficial.

Posture Management: Maintaining good posture is crucial. Recommendations include sleeping on a firm mattress or with a thin (or no) pillow under the head, and practicing standing against a wall with heels, bottom, shoulders, and head touching the wall^[11].

In severe cases, posture-correcting surgery may be an option^[11]. Depending on the specific type of spondyloarthritis, treatment may need to be adjusted. For example, in psoriatic arthritis, both the skin component and joint component must be treated, while in enteropathic arthritis, medications may need to be adjusted so the gastrointestinal component is also treated and not made worse^[11].

Living Well with Juvenile Spondyloarthritis

Managing Juvenile Spondyloarthritis requires more than just medical treatment. Lifestyle adjustments and self-care strategies play a crucial role in helping children and adolescents live healthy, active lives.

Stay Active: Regular exercise is essential for everyone with spondyloarthritis. It helps preserve posture, spine flexibility, and can relieve pain. Children should engage in activities they enjoy, including cardio exercise and strength training, not just stretching.

Healthy Diet: While there’s no one specific diet for Juvenile Spondyloarthritis, many people find that sticking with a healthy diet helps them feel better. Choose fresh vegetables, fruit, and whole grains while limiting red meat, sugar, soda, and junk foods.

Quality Sleep: Back pain may wake children up in the middle of the night, and lack of sleep can make them more sensitive to pain. Take medications as directed, avoid caffeine late in the day, limit screen time before bed, and exercise during the day to promote better sleep.

Stress Management: Living with a chronic disease is stressful. Finding healthy ways to manage stress that work for the child and family is important. This might include meditation, yoga, walks in nature, or spending time with pets.

Family Support: When a child is first diagnosed with Juvenile Spondyloarthritis, it’s important to ensure they understand they are not alone^[15]. Approaching the diagnosis as a team and providing emotional support while staying focused on the benefits of treatment helps develop confidence in managing the disease.

Maintaining Routine: Maintaining a daily routine, providing emotional support, and implementing self-care to stay balanced are all key elements to help children with this rheumatic disease live a healthy lifestyle^[15].

School Accommodations: Resources are available to help ensure children have everything they need, including any needed accommodations, to thrive in school^[1].

It’s important to note that compared to other categories of juvenile arthritis, children with Juvenile Spondyloarthritis have more frequent and higher intensity pain as well as poorer health status^[5]. These children are also less likely to achieve and sustain disease remission than those with other categories of juvenile arthritis, with less than 20 percent achieving remission within five years of diagnosis^[5]. However, with proper treatment and management, many children can lead fulfilling lives.

Juvenile Spondyloarthropathy, JSpA

• Spine
• Sacroiliac joint
• Pelvis
• Hips
• Knees
• Ankles
• Heels
• Entheses (tendon and ligament attachment sites)
• Eyes
• Digestive tract
• Rib cage