M08.1 Juvenile ankylosing spondylitis

Billable ICD-10-CM code, FY2026.

Excludes1 (never code together)

• ankylosing spondylitis in adults (M45.0-)

Applies from M08 Juvenile arthritis

Excludes1 (never code together)

• arthropathy in Whipple's disease (M14.8)
• Felty's syndrome (M05.0)
• juvenile dermatomyositis (M33.0-)
• psoriatic juvenile arthropathy (L40.54)

Code also

• any associated underlying condition, such as:
• regional enteritis [Crohn's disease] (K50.-)
• ulcerative colitis (K51.-)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 93 — Rheumatoid Arthritis and Other Specified Inflammatory Rheumatic Disorders
• CMS-HCC V22: HCC 40 — Rheumatoid Arthritis and Inflammatory Connective Tissue Disease
• RxHCC V08: HCC 83 — Rheumatoid Arthritis and Other Inflammatory Polyarthropathy
• ESRD V24: HCC 40

MS-DRG index

Defines the logic of DRG(s) 545-547 in MDC 08.

Approximate ICD-9-CM (GEMs)

• 720.0 Ankylosing spondylitis (approximate)

Code annotations containing back-references to M08.1

Back-references to M08.1

• Type 1 Excludes: M45 Ankylosing spondylitis ("juvenile (ankylosing) spondylitis (M08.1)")

Back-references to M08

• Type 1 Excludes: M05 Rheumatoid arthritis with rheumatoid factor ("juvenile rheumatoid arthritis (M08.-)")

Diagnosis Index entries for M08.1

• Spondylitis (chronic) › ankylosing (chronic) › juvenile
• Spondylitis (chronic) › juvenile ankylosing (chronic)

Nearby codes

• M08.072 Unspecified juvenile rheumatoid arthritis, left ankle and foot
• M08.079 Unspecified juvenile rheumatoid arthritis, unspecified ankle and foot
• M08.08 Unspecified juvenile rheumatoid arthritis, vertebrae
• M08.09 Unspecified juvenile rheumatoid arthritis, multiple sites
• M08.0A Unspecified juvenile rheumatoid arthritis, other specified site
• M08.1 Juvenile ankylosing spondylitis (this code)
• M08.2 Juvenile rheumatoid arthritis with systemic onset
• M08.20 Juvenile rheumatoid arthritis with systemic onset, unspecified site
• M08.21 Juvenile rheumatoid arthritis with systemic onset, shoulder
• M08.211 Juvenile rheumatoid arthritis with systemic onset, right shoulder
• M08.212 Juvenile rheumatoid arthritis with systemic onset, left shoulder