G37.9 — Demyelinating disease of central nervous system, unspecified
Is G37.9 billable?
Yes, but G37.9 is an unspecified code. G37.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, G37.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting G37.9 — the more specific alternatives are listed below.
More specific alternatives
- G37.0Diffuse sclerosis of central nervous system
- G37.1Central demyelination of corpus callosum
- G37.2Central pontine myelinolysis
- G37.3Acute transverse myelitis in demyelinating disease of central nervous system
- G37.4Subacute necrotizing myelitis of central nervous system
- G37.5Concentric sclerosis [Balo] of central nervous system
G37.9 at a glance
| Code | G37.9 |
|---|---|
| Description | Demyelinating disease of central nervous system, unspecified |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does G37.9 group to?
G37.9 sits in MDC 01 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 058Multiple Sclerosis and Cerebellar Ataxia with MCCmedical
- 059Multiple Sclerosis and Cerebellar Ataxia with CCmedical
- 060Multiple Sclerosis and Cerebellar Ataxia without CC/MCCmedical
As a secondary diagnosis, G37.9 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is G37.9 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to G37.9. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Degeneration, degenerative › myelin, central nervous system
- Demyelination, demyelinization › central nervous system
- Disease, diseased › demyelinating, demyelinizating
- Sclerosis, sclerotic › brain
- Syndrome › clinically isolated
- Syndrome › demyelinating
Inclusion terms
Alternative wording in documentation that is classified to G37.9.
- Clinically isolated syndromes
Excludes2 — not included here — inherited from Chapter 6
The conditions below are not part of G37.9, but a patient may have both at the same time. When documentation supports it, G37.9 and the excluded code may both 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)
How long has G37.9 existed?
G37.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which codes are confused with G37.9?
ICD-10-CM declares these codes mutually exclusive with G37.9 — exactly one of each pair can be correct for a given encounter.
What other codes are in the G37 family? (7)
- G37.0Diffuse sclerosis of central nervous system
- G37.1Central demyelination of corpus callosum
- G37.2Central pontine myelinolysis
- G37.3Acute transverse myelitis in demyelinating disease of central nervous system
- G37.4Subacute necrotizing myelitis of central nervous system
- G37.5Concentric sclerosis [Balo] of central nervous system
- G37.8Other specified demyelinating diseases of central nervous systemnot billable