### Date : 2024-06-16 11:19 ### Topic : Ankylosing spondylitis (강직성 척추염) #medicine #orthopedic #rheumatology ---- ### Ankylosing Spondylitis Overview **Ankylosing spondylitis (AS)** is a type of chronic inflammatory arthritis that primarily affects the spine and sacroiliac joints, causing pain and stiffness. Over time, the inflammation can lead to the fusion of the vertebrae, resulting in a loss of flexibility and a hunched-forward posture.  <Photo from: https://my.clevelandclinic.org/health/diseases/ankylosing-spondylitis> ### Pathophysiology Ankylosing spondylitis is an autoimmune disorder where the immune system attacks the body's own tissues, primarily affecting the spine. The exact cause is unknown, but it is believed to involve a combination of genetic and environmental factors. <mark style="background: #BBFABBA6;">The presence of the HLA-B27 gene is strongly associated with AS, although not all people with this gene develop the disease.</mark> ### Clinical Features - **Back Pain and Stiffness:** Chronic pain and stiffness in the lower back and buttocks, especially in the morning or after periods of inactivity. The pain typically improves with exercise and worsens with rest. - **Progressive Spine Stiffness:** Over time, the inflammation can lead to the fusion of the vertebrae (ankylosis), resulting in a loss of spinal mobility and a forward-stooped posture. - **Peripheral Joint Involvement:** Inflammation can also affect other joints, such as the hips, shoulders, and knees. - **Enthesitis:** Enthesitis is the medical term for **inflammation of one or more entheses**, which are sites where tendons and ligaments attach to bones. Enthesitis can cause symptoms such as joint pain and stiffness and problems with mobility. In AS, the Achilles tendon and plantar fascia are commonly affected. - **Extra-Articular Manifestations:** Some patients may experience uveitis (eye inflammation), cardiovascular issues, and lung involvement. ### Diagnosis Diagnosis is based on a combination of clinical features, physical examination, imaging, and laboratory tests: 1. **Clinical History:** Chronic back pain and stiffness, particularly in younger adults (onset typically before 45 years of age). 2. **Physical Examination:** - **Schober Test:** Reduced lumbar spine flexibility. - **Chest Expansion Test:** Reduced chest expansion due to involvement of costovertebral joints. 3. **Imaging:** - **X-rays:** Can show sacroiliitis (inflammation of the sacroiliac joints), vertebral squaring, and syndesmophytes (bony growths between vertebrae). - **MRI:** More sensitive in detecting early inflammation and sacroiliitis before changes are visible on X-rays. 4. **Laboratory Tests:** - **HLA-B27 Testing:** Presence of the HLA-B27 gene. - **Elevated Inflammatory Markers:** Increased ESR (erythrocyte sedimentation rate) and CRP (C-reactive protein). ### Example Case Study **Patient Profile:** - **Name:** Jee Hoon Ju - **Age:** 30 - **Gender:** Male - **Occupation:** Office Worker **Medical History:** - **Symptoms:** Jee Hoon Ju reports chronic lower back pain and stiffness for the past few years, particularly in the mornings and after prolonged periods of inactivity. The pain improves with exercise. He also notes occasional pain in his hips and heels. - **Family History:** His father has a history of similar back pain and was diagnosed with ankylosing spondylitis. **Physical Examination:** - **Schober Test:** Positive, with reduced lumbar spine flexibility. - **Chest Expansion Test:** Reduced chest expansion. **Imaging:** - **X-ray:** Shows bilateral sacroiliitis. - **MRI:** Reveals early signs of inflammation in the sacroiliac joints. **Laboratory Tests:** - **HLA-B27:** Positive. - **Inflammatory Markers:** Elevated ESR and CRP. **Diagnosis:** Based on Jee Hoon Ju’s symptoms, physical examination, imaging, and laboratory test results, he is diagnosed with ankylosing spondylitis. ### Management 1. **Medications:** - **NSAIDs:** First-line treatment to reduce pain and inflammation (e.g., ibuprofen, naproxen). - **TNF Inhibitors:** Biologic drugs like etanercept and infliximab for patients who do not respond to NSAIDs. - **IL-17 Inhibitors:** Another class of biologics like secukinumab. 2. **Physical Therapy:** - Regular exercise and stretching to maintain spinal flexibility and posture. - Strengthening exercises for core muscles. 3. **Lifestyle Modifications:** - Encouraging regular physical activity. - Maintaining good posture. - Avoiding smoking, as it can exacerbate symptoms. 4. **Monitoring and Follow-Up:** - Regular follow-up visits to monitor disease progression and response to treatment. - Assessment for extra-articular manifestations and complications. 5. **Surgery:** - In severe cases with significant joint damage, surgical options like joint replacement may be considered. ### Conclusion Ankylosing spondylitis is a chronic, progressive inflammatory condition primarily affecting the spine. Early diagnosis and a comprehensive management plan, including medication, physical therapy, and lifestyle modifications, are essential to control symptoms, maintain function, and improve quality of life for patients like Jee Hoon Ju. Regular monitoring and treatment adjustments are crucial to managing this lifelong condition.