M04.9 Autoinflammatory syndrome, unspecified

Billable ICD-10-CM code, FY2026.

Applies from M04 Autoinflammatory syndromes

Excludes2 (not included here)

• Crohn's disease (K50.-)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 94 — Systemic Lupus Erythematosus and Other Specified Systemic Connective Tissue 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)

• 710.9 Unspecified diffuse connective tissue disease (approximate)

Code annotations containing back-references to M04.9

Back-references to M04

• Code Also: E85.0 Non-neuropathic heredofamilial amyloidosis ("autoinflammatory syndromes (M04.-)")

Diagnosis Index entries for M04.9

• Disease, diseased › autoinflammatory
• Syndrome › autoinflammatory

Nearby codes

• M04 Autoinflammatory syndromes
• M04.1 Periodic fever syndromes
• M04.2 Cryopyrin-associated periodic syndromes
• M04.8 Other autoinflammatory syndromes
• M04.9 Autoinflammatory syndrome, unspecified (this code)