G11.9
Hereditary ataxia, unspecified
Billable FY2026 2025-10-01 → 2026-09-30
This is the unspecified option. 8 more
specific codes sit alongside it. Worth
checking whether the documentation supports one of them.
Exclusions 11 never code together
G11code
G00-G99chapter
Excludes2
- certain conditions originating in the perinatal period (P04-P96)P04-P96
- certain infectious and parasitic diseases (A00-B99)A00-B99
- complications of pregnancy, childbirth and the puerperium (O00-O9A)O00-O9A
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)Q00-Q99
- endocrine, nutritional and metabolic diseases (E00-E88)E00-E88
- injury, poisoning and certain other consequences of external causes (S00-T88)S00-T88
- neoplasms (C00-D49)C00-D49
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)R00-R94
Excludes2 — not included here, but the patient may have both. Code both when documented.
Instructional notes 4
G11.9code
Inclusion terms
- Hereditary cerebellar ataxia NOS
- Hereditary cerebellar degeneration
- Hereditary cerebellar disease
- Hereditary cerebellar syndrome
Index entries leading here 6
- Ataxia, ataxy, ataxic R27.0
- Paralysis, paralytic (complete) (incomplete) G83.9
- ataxic (hereditary) G11.9
- Syndrome — see also Disease
- cerebellar
- hereditary G11.9
- cerebellar
- Sclerosis, sclerotic
- hereditary
- cerebellar G11.9
- hereditary
- Degeneration, degenerative
- Disease, diseased — see also Syndrome
- spinocerebellar (hereditary) G11.9
Alongside this code 8 same parent — G11
G11.0 Congenital nonprogressive ataxia G11.1 Early-onset cerebellar ataxia category G11.2 Late-onset cerebellar ataxia 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
Additional references
AHA Coding Clinic® Licence required
Official coding advice for this code. Published by the American Hospital Association. Not included in this installation.