2026 ICD-10-CM Diagnosis Code G09Sequelae of inflammatory diseases of central nervous system
ICD-10-CM Codes›G00–G99›G00-G09›G09
- Billable — Valid for Submission
- Not Chronic
G09 is a billable ICD-10-CM diagnosis code for sequelae of inflammatory diseases of central nervous system. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 91 through 93. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Sequela of specified nervous system conditions.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Hydrocephalus due to and following meningitis
- Hydrocephalus following infectious disease
- Late effects of intracranial abscess or pyogenic infection
- Late effects of pyogenic intracranial abscess
- Obstructive hydrocephalus
- Obstructive hydrocephalus due to and following meningitis
- Postinfectious hydrocephalus
- Secondary tic disorder
- Sequela of infectious meningitis
- Sequelae of inflammatory diseases of the central nervous system
- Sequelae of meningitis
- Tic disorder due to post-encephalitic syndrome
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Code First
- condition resulting from (sequela) of inflammatory diseases of central nervous system
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) L02.91
Parencephalitis See Also: Encephalitis;
sequelae G09
Sequelae (of) See Also: condition;
Suppuration, suppurative See Also: condition;
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Brain Diseases
Your brain is the control center of your body. It controls your thoughts, memory, speech, and movement. It regulates the function of many organs. It's part of your nervous system, which also includes your spinal cord and peripheral nerves. The nervous system sends signals between your brain and the rest of the body.
Read the full article at MedlinePlus
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Convert G09 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About G09Overview
What is the ICD-10 code for sequelae of inflammatory diseases of central nervous system?
The ICD-10-CM code for sequelae of inflammatory diseases of central nervous system is G09. It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is G09 (Sequelae of inflammatory diseases of central nervous system) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report sequelae of inflammatory diseases of central nervous system on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does G09 group to?
When sequelae of inflammatory diseases of central nervous system is the principal diagnosis on an inpatient stay, it groups to MS-DRG 91, 92, 93, with relative weights from 0.7963 to 1.7562 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of G09?
Under the General Equivalence Mappings, sequelae of inflammatory diseases of central nervous system converts to ICD-9-CM 326 (late eff cns abscess). The mapping is approximate, so confirm the match fits the documentation.
