2026 ICD-10-CM Diagnosis Code G01Meningitis in bacterial diseases classified elsewhere
ICD-10-CM Codes›G00–G99›G00-G09›G01
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Not Chronic
G01 is a billable ICD-10-CM diagnosis code for meningitis in bacterial diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 23 through 24, 94 through 96, 791, 793. As a secondary diagnosis, it counts as a major complication or comorbidity (MCC) and places an inpatient stay in the highest severity level of its MS-DRG family. It does not count, however, when the principal diagnosis is one of 106 closely related codes. The code is a manifestation code that cannot be reported as the principal diagnosis. Coders also document this condition as meningitis caused by Nocardia. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections and Meningitis.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for G01.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Meningitis caused by Nocardia
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Code First
- underlying disease
Type 1 Excludes
- meningitis (in):
- gonococcal A54.81
- leptospirosis A27.81
- listeriosis A32.11
- Lyme disease A69.21
- meningococcal A39.0
- neurosyphilis A52.13
- tuberculosis A17.0
- meningoencephalitis and meningomyelitis in bacterial diseases classified elsewhere G05
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.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Patient EducationClinical
Meningitis
Meningitis is inflammation of the thin tissue that surrounds the brain and spinal cord, called the meninges. There are several types of meningitis. The most common is viral meningitis. You get it when a virus enters the body through the nose or mouth and travels to the brain. Bacterial meningitis is rare but can be deadly.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert G01 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About G01Overview
What is the ICD-10 code for meningitis in bacterial diseases classified elsewhere?
The ICD-10-CM code for meningitis in bacterial diseases classified elsewhere is G01. It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is G01 (Meningitis in bacterial diseases classified elsewhere) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report meningitis in bacterial diseases classified elsewhere on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does G01 group to?
On inpatient claims, meningitis in bacterial diseases classified elsewhere maps to MS-DRG 23, 24, 94, 95, 96, 791, 793, with relative weights from 2.5792 to 5.7303 depending on complications. Higher weights mean higher Medicare reimbursement.
Is G01 a CC or MCC?
CMS lists G01 as an MCC (major complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it places the inpatient stay in the highest-weighted DRG of its severity family. It does not count when the principal diagnosis is one of the 106 closely related codes in its exclusion list.
Can G01 be a principal diagnosis?
No. This is a manifestation code: meningitis in bacterial diseases classified elsewhere describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.
