G11.2 Late-onset cerebellar ataxia

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

Applies from G11 Hereditary ataxia

Excludes2 (not included here)

• cerebral palsy (G80.-)
• hereditary and idiopathic neuropathy (G60.-)
• metabolic disorders (E70-E88)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 200 — Friedreich and Other Hereditary Ataxias; Huntington Disease
• CMS-HCC V22: HCC 72 — Spinal Cord Disorders/Injuries
• ESRD V24: HCC 72

MS-DRG index

Defines the logic of DRG(s) 058-060 in MDC 01.

Approximate ICD-9-CM (GEMs)

• 334.2 Primary cerebellar degeneration (approximate)

Medicare Code Edits (MCE v43.1 (April 2026))

• Adult diagnoses (age 15 through 124): Age conflict edit. These diagnoses are clinically expected only in patients age 15 through 124.

Code annotations containing back-references to G11.2

Back-references to G11

• Type 1 Excludes: R26 Abnormalities of gait and mobility ("hereditary ataxia (G11.-)")
• Type 1 Excludes: R27 Other lack of coordination ("hereditary ataxia (G11.-)")

Diagnosis Index entries for G11.2

• Ataxia, ataxy, ataxic › cerebellar (hereditary) › late-onset (Marie's)
• Ataxia, ataxy, ataxic › Marie's (cerebellar) (heredofamilial) (late- onset)
• Ataxia, ataxy, ataxic › Sanger-Brown's (hereditary)
• Marie's › cerebellar ataxia (late-onset)
• Sanger-Brown ataxia

Nearby codes

• G11.0 Congenital nonprogressive ataxia
• G11.1 Early-onset cerebellar ataxia
• G11.10 Early-onset cerebellar ataxia, unspecified
• G11.11 Friedreich ataxia
• G11.19 Other early-onset cerebellar ataxia
• G11.2 Late-onset cerebellar ataxia (this code)
• G11.3 Cerebellar ataxia with defective DNA repair
• G11.4 Hereditary spastic paraplegia
• G11.5 Hypomyelination - hypogonadotropic hypogonadism - hypodontia
• G11.6 Leukodystrophy with vanishing white matter disease
• G11.8 Other hereditary ataxias