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  6. 2024 ICD-10-CM Code G31.9

2024 ICD-10-CM Diagnosis Code G31.9

Degenerative disease of nervous system, unspecified

ICD-10-CM Code:
G31.9
ICD-10 Code for:
Degenerative disease of nervous system, unspecified
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Chronic
Code Navigator:

Code Classification

  • Diseases of the nervous system
    (G00–G99)
    • Other degenerative diseases of the nervous system
      (G30-G32)
      • Other degenerative diseases of nervous system, not elsewhere classified
        (G31)

G31.9 is a billable diagnosis code used to specify a medical diagnosis of degenerative disease of nervous system, unspecified. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

Unspecified diagnosis codes like G31.9 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Acquired cerebral atrophy
  • Autonomic nervous system disorder co-occurrent and due to neurodegenerative disorder
  • Cerebellar degeneration
  • Cerebral atrophy
  • Cerebral degeneration
  • Cerebral degeneration due to Creutzfeldt-Jakob disease
  • Cerebral degeneration due to Parkinson's disease
  • Cerebral degeneration presenting primarily with dementia
  • Chorea due to heredodegenerative disorder
  • Chronic deafness
  • Circumscribed atrophy of brain
  • Degenerative brain disorder
  • Degenerative disease of the central nervous system
  • Epilepsy co-occurrent and due to degenerative brain disorder
  • Frontal lobe degeneration
  • Frontal lobe degeneration with motor neurone disease
  • Frontotemporal degeneration
  • Gemignani syndrome
  • Microphthalmia with brain atrophy syndrome
  • Parkinsonian pyramidal syndrome
  • Parkinsonism due to heredodegenerative disorder
  • Parkinsonism due to heredodegenerative disorder
  • Posterior cortical atrophy syndrome
  • Prieto Badia Mulas syndrome
  • Progressive focal cortical atrophy
  • Secondary cerebellar degeneration

Clinical Classification

Clinical CategoryCCSR Category CodeInpatient Default CCSROutpatient Default CCSR
Neurocognitive disordersNVS011Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.
Other nervous system disorders (often hereditary or degenerative)NVS006N - Not default inpatient assignment for principal diagnosis or first-listed diagnosis.N - Not default outpatient assignment for principal diagnosis or first-listed diagnosis.

Clinical Information

  • CDR1 Gene|CDR1|CDR1|Cerebellar Degeneration-Related Protein-1 (34kD) Gene

    this gene plays a major role in antigens that are specifically expressed in neuronal cells.

  • CDR1 wt Allele|CDR|CDR Gene|CDR1|CDR34|CDR34 Gene|CDR62A|CDR62A Gene|Cerebellar Degeneration-Related Autoantigen 1 Gene|Cerebellar Degeneration-Related Protein (34kD) Gene|Cerebellar Degeneration-Related Protein-1 (34kD) wt Allele|Cerebellar-Degeneration-Related Antigen 1 Gene

    human cdr1 wild-type allele is located within xq27.1-q27.2 and is approximately 1 kb in length. this allele, which encodes cerebellar degeneration-related antigen 1 protein, is involved in immune reactions and neuronal antigen regulation.

  • Cerebellar Degeneration

    degeneration of the cerebellum. it may be an inherited condition, a paraneoplastic syndrome, or secondary to autoimmune disorders.

  • Cerebellar-Degeneration-Related Antigen 1|CDR|CDR1|CDR1 Protein|CDR34|CDR62A|Cerebellar Degeneration-Related Autoantigen 1|Cerebellar Degeneration-Related Autoantigen, 34-kD|Cerebellar Degeneration-Related Protein (34kD)|Cerebellar Degeneration-Related Protein 1|Cerebellar Degeneration-Related Protein 1, 34kDa|Cerebellar Degeneration-Related Protein-1 (34kD)

    cerebellar degeneration-related antigen 1 (262 aa, ~31 kda) is encoded by the human cdr1 gene. this protein is involved in autoimmune diseases.

  • Paraneoplastic Cerebellar Degeneration

    a rare, immune-mediated disorder characterized by cerebellar degeneration due to the presence of an often undetected malignancy (usually carcinoma or lymphoma) in an anatomic site other than the cerebellum. signs and symptoms include progressive ataxia, dysarthria, and nystagmus.

  • Spinocerebellar Ataxia|Spinocerebellar Degeneration

    an inherited disorder characterized by degeneration of the spinal cord and the cerebellum. symptoms may appear at any age and include progressive loss of coordination of gait, hands, speech, and eye movements.

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Convert G31.9 to ICD-9-CM

  • ICD-9-CM Code: 330.9 - Cereb degen in child NOS
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.
  • ICD-9-CM Code: 331.9 - Cereb degeneration NOS
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.