G00.0

Hemophilus meningitis

FY2027Chapter 6: Diseases of the nervous system/G00–G09 Inflammatory diseases of the central nervous system

BillableComplete code, valid to report

G00.0 (also written G000) is a billable ICD-10-CM diagnosis code for hemophilus meningitis. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 6 codes in category G00 (Bacterial meningitis, not elsewhere classified). The Alphabetic Index lists it under 7 entries. Its coding notes include 2 Excludes1 entries and 8 Excludes2 entries.

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Inherited from G00 Bacterial meningitis, not elsewhere classified
  • bacterial meningoencephalitis (G04.2)
  • bacterial meningomyelitis (G04.2)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (8 notes)
Inherited from Chapter 6 Diseases of the nervous system
  • 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)

Care settings

How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.

Home Health Primary

Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the Neuro Rehabilitation clinical group.

Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026

IRF 60% Rule

On the CMS list of diagnoses used to determine presumptive compliance with the IRF 60 percent rule.

Source: CMS IRF Presumptive Compliance-3, FY 2027 IRF PPS final rule files, effective for discharges on or after October 1, 2026

Hospital MCC

Counts as a major complication or comorbidity (MCC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 106 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.

Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix C

Includes

Further defines or gives examples of the content of the category.

Inherited from G00 Bacterial meningitis, not elsewhere classified
  • bacterial arachnoiditis
  • bacterial leptomeningitis
  • bacterial meningitis
  • bacterial pachymeningitis

Inclusion terms

Conditions classified to this code.

This code
  • Meningitis due to Hemophilus influenzae

Alphabetic Index terms

Terms the official Alphabetic Index lists for this code. 7 entries