Spondylitis, also called spondyloarthritis, is an autoimmune and autoinflammatory disease that causes arthritis, back pain, and other symptoms throughout the body. Spondylitis encompasses several types of spondyloarthropathies (long-term diseases of the joints), including ankylosing spondylitis (AS), reactive arthritis, and psoriatic spondylitis — also called psoriatic arthritis (PsA).

Some types of spondylitis are defined by what other related conditions a person has. Spondylitis commonly has many extra-articular manifestations, meaning they affect different parts of the body besides the joints. The underlying processes behind spondylitis, such as HLA-B27 gene mutations, differ from those of other types of autoimmune diseases, such as rheumatoid arthritis (RA). However, these processes share the same end result: chronic systemic inflammation.

Although spondylitis does not frequently occur alongside autoimmune disorders, such as lupus and rheumatoid arthritis, it can occur alongside some, including psoriasis and inflammatory bowel disease (IBD). If you or a loved one have been diagnosed with spondylitis, it’s important to understand which conditions may be connected to the spondylitis.

Conditions Related To Specific Types of Spondylitis

There are two types of spondylitis, defined both by the type of arthritis symptoms that they cause and the presence of other autoimmune diseases. Enteropathic arthritis is associated with IBD and psoriatic arthritis is associated with psoriasis.

Inflammatory Bowel Disease

Inflammatory bowel disease, which includes Crohn’s disease and ulcerative colitis, is an autoimmune disease seen in people diagnosed with enteropathic arthritis. IBD can affect the entire intestinal tract and can cause severe pain and disability, significantly increase risk of colorectal cancer, and cause life-threatening complications.

Psoriasis

Psoriasis is a common autoimmune disease that can cause raised, scaly patches on the skin due to systemic inflammation. PsA is a condition that is associated with psoriasis and peripheral arthritis affecting the joints of the extremities.

Musculoskeletal Conditions Related to Spondylitis

Spondylitis primarily affects the spine and pelvis. Spinal involvement with spondylitis usually begins as sacroiliitis, inflammation of the sacroiliac joint that joins the spine and pelvis. However, spondylitis can cause joint pain throughout the body. The condition can also be connected with other diseases that affect the bones and muscles.

Curvature of the Spine

Common complications of ankylosing spondylitis include fusion of the vertebra in the spine and scoliosis (sideways curvature of the spine), but spondylitis can also cause other spinal deformities. Advanced or untreated AS can result in kyphosis, a forward curvature of the upper spine that causes a hunched-over appearance.

Osteoporosis

Osteoporosis is a common complication of spondylitis and other autoimmune and chronic inflammatory disorders. Osteoporosis is a loss of bone density that leads to brittle bones and an increased risk of fractures. One study found that more than 20 percent of people over the age of 50 with AS had developed osteoporosis, and more than 40 percent had developed osteopenia, an early stage of bone mineral-density loss. Long-term corticosteroid treatment can also contribute to osteopenia and osteoporosis.

Costochondritis

Spondylitis can also be connected to costochondritis, inflammation of the cartilage where the ribs meet the breastbone. This can cause temporary, but intense, chest pain that can be mistaken for heart pain due to angina (chest pain) or a heart attack.

Enthesitis

Enthesitis is inflammation at the entheses, the places where tendons connect to bone. The condition can lead to pain and the pathologic formation of new bone, such as bone spurs. Enthesitis frequently affects the heels at the Achilles tendon and can cause plantar fasciitis — inflammation of the dense band of tissue of the sole of the foot, causing heel or arch pain.

Heart Conditions

Spondylitis can increase the risk of several types of heart disease due to inflammation and long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs). Up to 10 percent of people with AS also have a heart condition, according to the Spondylitis Association of America.

Coronary Artery Disease

Coronary artery disease (CAD) causes loss of blood flow to the heart muscle, resulting in angina and heart attack. Spondylitis significantly increases the risk of CAD and associated diseases like high blood pressure and atherosclerosis — the thickening and stiffening of the arteries.

Aortitis

Aortitis is inflammation of the aorta, the large artery which exits the heart carrying oxygenated blood to the body. Aortitis can cause aortic insufficiency, high blood pressure, and, over time, aortic valve regurgitation, where blood “leaks” back into the heart from the aorta.

Arrhythmias

Spondylitis can be connected to conduction disorders and arrhythmia, abnormal heart rhythm. Conduction disturbances prevent the normal flow of electrical impulses in the heart, leading to a heart rate that is too fast (tachycardia) or too slow (bradycardia). It can also result in disorganized heart contractions, such as atrial fibrillation. These arrhythmias can be severe and life-threatening.

Cardiomyopathy

Cardiomyopathy, inflammation of the heart muscle, can occur with spondylitis. Cardiomyopathy weakens the heart muscle, leading to an enlarged heart and heart failure, a severe and debilitating condition that can cause cardiac arrest.

Eye Conditions Related to Spondylitis

Spondylitis and other autoimmune diseases, such as rheumatoid arthritis, can cause eye inflammation. Spondylitis is associated with uveitis, inflammation of the uvea, and iritis, inflammation of the iris. These can lead to pain and vision changes, as well as more serious conditions like glaucoma.

Fatigue

Spondylitis and other inflammatory disorders can cause generalized symptoms that affect the whole body. Chronic fatigue, tiredness that is not relieved with rest, is a common comorbidity with spondylitis that can be debilitating.

Lung Complications

Advanced ankylosing spondylitis can cause curvature of the spine and fusions of vertebrae that affect breathing and lung function. This dramatically limited movement of the chest wall can result in lung disease such as pulmonary fibrosis and an increased risk of lung infections.

Nerve Complications

Axial spondyloarthritis, spondylitis that affects the spine, can have serious complications that involve the spinal cord. Cauda equina syndrome (CES) is a very serious condition where the nerve roots that extend from the end of the spinal cord through the lumbar spine and sacrum can become damaged.

Cauda equina syndrome can cause pain, numbness, and weakness from the lower back to the lower extremities. It can also involve other organs, leading to urinary retention, urinary and fecal incontinence, and sexual dysfunction. Treatment for CES may require immediate surgery to try to prevent permanent nerve damage.

Effect of Complications and Comorbidities

The vast array of possible complications and comorbidities of spondylitis can paint a frustrating picture of life with this chronic disease, but the prognosis for most cases of spondylitis is not as bad as it sounds. Most people do not develop life-threatening complications from spondylitis, and early diagnosis and treatment can prevent or limit many of these complications.

The life expectancy for individuals with spondylitis is typically normal, except in severe or advanced cases, such as ankylosing spondylitis with spinal changes visible in X-ray images. It is important to know the possible complications and comorbidities of chronic illness so that you and your health care provider can be on the lookout for symptoms and decrease risk factors for complications.

Condition Guide

• What Is Spondylitis?
• Spondylitis Types
• Spondylitis — The Path to Diagnosis
• What Causes Spondylitis?
• Spondylitis Treatment
• Spondylitis vs. Spondylosis: Are They One and the Same?