ICD-10-CM 2027
ICD-10 code for sequelae parencephalitis
From the official ICD-10-CM alphabetic index entry “Parencephalitis › sequelae”. Page updated September 29, 2026.
About coding sequelae parencephalitis
The ICD-10-CM code for sequelae parencephalitis is G09 (Sequelae of inflammatory diseases of central nervous system).
Code first: condition resulting from (sequela) of inflammatory diseases of central nervous system.
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 091 (Other Disorders of Nervous System with MCC, relative weight 1.7046), DRG 092 (Other Disorders of Nervous System with CC, relative weight 1.0239) and DRG 093 (Other Disorders of Nervous System without CC/MCC, relative weight 0.7783), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
Common questions about sequelae parencephalitis ICD-10 codes
What is the ICD-10 code for sequelae parencephalitis?
- G09 — Sequelae of inflammatory diseases of central nervous system.
Is G09 billable?
- Yes. G09 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can G09 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict G09 as a principal diagnosis.
Is G09 a CC or MCC?
- No. G09 is neither a CC nor an MCC under MS-DRG v44.0.