2027 ICD-10-CM Diagnosis Code G32.81Cerebellar ataxia in diseases classified elsewhere
ICD-10-CM Codes›G00–G99›G30-G32›G32
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 182
- Chronic Condition
G32.81 is a billable ICD-10-CM diagnosis code for cerebellar ataxia in diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 58 through 60. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 175 closely related codes. The code is a manifestation code that cannot be reported as the principal diagnosis. Coders also document this condition as amyotrophic lateral sclerosis plus syndrome. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other nervous system disorders (often hereditary or degenerative).
For Medicare Advantage risk adjustment, G32.81 maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries) under the V28 model, adding a risk factor of about 0.478 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for G32.81.
Medicare Risk Adjustment (HCC)Billing
G32.81 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.
Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Amyotrophic lateral sclerosis plus syndrome
- Amyotrophic lateral sclerosis with spinocerebellar ataxia
- Bird-headed dwarfism with progressive ataxia, insulin-resistant diabetes, goiter, and primary gonadal insufficiency
- Cerebellar ataxia associated with another disorder
- Cerebellar ataxia caused by chemical
- Myelopathy due to nutritional deficiency
- Spinocerebellar ataxia due to vitamin E deficiency
- Substance-induced ataxia
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to G32.81: its own notes plus those printed at G32.8 and Chapter 6. A note printed at a category, block or chapter applies to every code under it.
Excludes1
Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Code First
The underlying condition named in the note is sequenced before this code.
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Referenced in Other NotesGuidance
Instructional notes printed at other codes that name G32.81, its category, or a range that includes it.
Use Additional Code 1
These codes say to use an additional code from the note, and G32.81 is one of the codes named.
- K90.0 Celiac diseasegluten ataxia (G32.81)
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Cerebellar Disorders
When you play the piano or hit a tennis ball you are activating the cerebellum. The cerebellum is the area of the brain that controls coordination and balance. Problems with the cerebellum include:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert G32.81 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About G32.81Overview
What is the ICD-10 code for cerebellar ataxia in diseases classified elsewhere?
The ICD-10-CM code for cerebellar ataxia in diseases classified elsewhere is G32.81 (sometimes written as G3281). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is G32.81 a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report cerebellar ataxia in diseases classified elsewhere on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does G32.81 group to?
On inpatient claims, cerebellar ataxia in diseases classified elsewhere maps to MS-DRG 60, 58, 59, with relative weights from 0.9248 to 1.8430 depending on complications. Higher weights mean higher Medicare reimbursement.
Is G32.81 a CC or MCC?
CMS lists G32.81 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 175 closely related codes in its exclusion list.
Can G32.81 be a principal diagnosis?
No. This is a manifestation code: cerebellar ataxia in diseases classified elsewhere describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.
What HCC is G32.81?
G32.81 (cerebellar ataxia in diseases classified elsewhere) maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries), commonly written as HCC 182, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 72 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.
Does G32.81 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, G32.81 adds a risk adjustment factor of about 0.478 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.270 to 0.478 depending on the payment segment). A more severe related category (HCC 180, HCC 181, HCC 191, and HCC 192) supersedes it when both are reported. See the full factor table on the HCC 182 category page.
