Ankylosing Spondylitis (AS)

Ankylosing Spondylitis (AS) is a chronic autoimmune inflammatory arthritis that primarily affects the spine and sacroiliac joints (where the spine meets the pelvis). Over time, AS can cause the vertebrae to fuse together, resulting in a rigid or curved spine, known as bamboo spine. The disease can also affect other joints, eyes, and organs, and symptoms tend to appear in young adults, especially men under 40.

Chronic lower back pain especially in the early morning or after rest; Stiffness in the hips, pelvis, or lower spine; Pain improves with movement not with rest; Reduced flexibility in the spine; Fatigue; Inflammation in the eyes (uveitis) causing redness, pain, or blurred vision; Pain in shoulders, ribs, knees, or feet (enthesitis).

Exact cause is unknown, but strongly linked to genetics especially the HLA-B27 gene. Possibly triggered by infections or gut microbiome imbalance. Immune system mistakenly attacks the joints and entheses.

Medical history and physical exam; X-rays or MRI scans to detect inflammation or spinal fusion; HLA-B27 genetic test (positive in 80-90% of AS cases); Blood tests - may show elevated ESR or CRP (inflammation markers).

No cure, but treatment helps reduce symptoms and slow progression: NSAIDs (e.g., naproxen, indomethacin) - first-line treatment; Biologic therapies - TNF inhibitors (e.g., adalimumab) or IL-17 blockers (e.g., secukinumab); Physical therapy to maintain posture and flexibility; Exercise and posture training; Surgery (rare, for severe joint damage or spinal deformity).

Symptoms may worsen slowly over time. With early diagnosis and proper treatment, many people maintain good mobility. Severe cases may lead to spinal fusion, breathing restriction, or loss of mobility. Eye inflammation, heart problems, or GI issues may develop in some people.

Affects approximately 0.1% to 1.4% of the U.S. population. Most common in young men between ages 15 and 40. More common in people with HLA-B27 gene, especially those of Northern European descent.