approach to diagnose ankylosing spondylitis.pptx

ankylosing spondylitis

1. ANKYLOSING SPONDILITIS

2. Referred to as Bechterew’s disease or Marie Strümpell disease Chronic seronegative autoimmune spondyloarthropathy characterized by bridging spinal osteophyte formation, enthesitis, sacroiliitis, and uveitis.  Diagnostic criteria  : bilateral sacroiliitis +/- uveitis   HLA-B27 positive (90% positive)  

3. Incidence - affects ~0.2% of Caucasian population Demographics 4:1 male:female Peaks at 17 to 35 years of age juvenile form <16-years-old includes enthesitis   fewer than 10% of HLA-B27 positive patients have symptoms of AS

4. Pathophysiology of Ankylosing Spondylitis 1.Genetic Predisposition (HLA-B27): The exact mechanism by which HLA-B27 contributes to AS is still under investigation, but one theory suggests that HLA-B27 misfolds, triggering an immune response that leads to chronic inflammation. Leading to peptides aggregation in the joint and leads to a degenerative cascade Mediating Cytotoxic T-cell autoimmune reaction against HLA-B27

5. 2. Inflammation of Entheses (Enthesitis): The inflammation begins at the entheses , which are the points where tendons, ligaments, and joint capsules attach to bone. Enthesitis is a hallmark of AS and can occur in the spine, pelvis, and peripheral joints (e.g., Achilles tendon, plantar fascia). Persistent inflammation in these areas leads to local tissue damage, bony erosion, surrounding soft-tissue ossification, and eventually joint ankylosis . preferentially targets sacroiliac joints, spinal apophyseal joints, symphysis pubis

6. 3. Chronic Inflammation and New Bone Formation: The ongoing inflammation in the spine and SI joints leads to osteitis , a bone marrow inflammation. Over time along with ,inflammation of the annulus lead to bridging osteophyte formation ( syndesmophytes ) causing ankylosis (fusion of joints). stiffening and loss of mobility. The vertebrae may fuse together, creating what’s known as a "bamboo spine"