Ankylosing spondylitis

This code represents a chronic, inflammatory arthritic condition primarily affecting the spine and sacroiliac joints, leading to progressive stiffness and fusion. It is a systemic rheumatic disease characterized by inflammation of the entheses, the sites where tendons and ligaments attach to bone.

Use this code for patients diagnosed with ankylosing spondylitis, often presenting with chronic back pain, particularly in the morning or after inactivity, and improved with exercise. Documentation should clearly state the diagnosis of ankylosing spondylitis, supported by clinical findings, imaging (e.g., sacroiliitis on X-ray or MRI), and laboratory tests (e.g., HLA-B27 positivity).

• Ensure documentation specifies "ankylosing spondylitis" and not just general spondylitis or back pain.
• Consider sequencing this code as the primary diagnosis when it is the reason for the encounter or treatment.
• Do not confuse with other forms of spondylopathy or inflammatory arthropathies without clear documentation of ankylosing spondylitis.