M35.89 Other specified systemic involvement of connective tissue

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applies from M35 Other systemic involvement of connective tissue

Excludes1 (never code together)

• reactive perforating collagenosis (L87.1)

Risk adjustment (HCC)

• CMS-HCC V22: HCC 40 — Rheumatoid Arthritis and Inflammatory Connective Tissue Disease
• RxHCC V08: HCC 84 — Systemic Lupus Erythematosus and Other Systemic Connective Tissue Disorders
• ESRD V24: HCC 40

MS-DRG index

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

Code annotations containing back-references to M35.89

Back-references to M35

• Type 2 Excludes: I77 Other disorders of arteries and arterioles ("collagen (vascular) diseases (M30-M36)")
• Type 2 Excludes: J82 Pulmonary eosinophilia, not elsewhere classified ("pulmonary eosinophilia due to systemic connective tissue disorders (M30-M36)")
• Code First: J84.170 Interstitial lung disease with progressive fibrotic phenotype in diseases classified elsewhere ("systemic connective tissue disorders (M30-M36)")
• Type 1 Excludes: L94 Other localized connective tissue disorders ("systemic connective tissue disorders (M30-M36)")

Diagnosis Index entries for M35.89

• Collagenosis, collagen disease (nonvascular) (vascular) › specified NEC
• Disease, diseased › collagen NOS (nonvascular) (vascular) › specified NEC
• Disease, diseased › connective tissue, systemic (diffuse) › specified NEC
• Eosinophilia-myalgia syndrome
• Syndrome › eosinophilia-myalgia

Nearby codes

• M35.5 Multifocal fibrosclerosis
• M35.6 Relapsing panniculitis [Weber-Christian]
• M35.7 Hypermobility syndrome
• M35.8 Other specified systemic involvement of connective tissue
• M35.81 Multisystem inflammatory syndrome
• M35.89 Other specified systemic involvement of connective tissue (this code)
• M35.9 Systemic involvement of connective tissue, unspecified