ICD-10-CM 2027 diagnosis code
A06.6Amebic brain abscess
A06.6 is a valid, billable ICD-10-CM code for amebic brain abscess. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About A06.6
A06.6 is the ICD-10-CM diagnosis code for amebic brain abscess. It belongs to category A06 (amebiasis), block A00-A09 (intestinal infectious diseases) and chapter 1 (certain infectious and parasitic diseases). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within A06 (amebiasis), A06.6 is specifically for amebic brain abscess. Related codes cover acute amebic dysentery (A06.0), chronic intestinal amebiasis (A06.1), amebic nondysenteric colitis (A06.2), Ameboma of intestine (A06.3), amebic liver abscess (A06.4), amebic lung abscess (A06.5), cutaneous amebiasis (A06.7), amebic infection of other sites (A06.8) and 1 more.
As a secondary diagnosis it is an MCC (major complication or comorbidity), which can move an inpatient stay into the highest-paying "with MCC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 023 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator, relative weight 5.7444), DRG 024 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis without MCC, relative weight 3.9708), DRG 097 (Non-Bacterial Infection of Nervous System Except Viral Meningitis with MCC, relative weight 3.8226), DRG 098 (Non-Bacterial Infection of Nervous System Except Viral Meningitis with CC, relative weight 2.2706) and DRG 099 (Non-Bacterial Infection of Nervous System Except Viral Meningitis without CC/MCC, relative weight 1.5256), 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.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 006.5 (amebic brain abscess).
Coding notes
- Amebic abscess of brain (and liver) (and lung)
Notes that apply from higher levels
Instructions written at a parent level also apply to A06.6.
› From A06 Amebiasis
Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.
Alphabetic index entries
4 entriesTerms in the official ICD-10-CM index that lead to A06.6.
- Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › amebic › brain (and liver or lung abscess)
- Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › brain (any part) (cystic) (otogenic) › amebic (with abscess of any other site)
- Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › liver (cholangitic) (hematogenic) (lymphogenic) (pylephlebitic) (pyogenic) › amebic (due to Entamoeba histolytica) (dysenteric) (tropical) › with › brain abscess (and liver or lung abscess)
- Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic) › lung (miliary) (putrid) › amebic (with liver abscess) › with › brain abscess
Codes whose notes reference A06.6
- G07Excludes1
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 01 · Diseases and Disorders of the Nervous System
MDC 01 · Diseases and Disorders of the Nervous System
ICD-9-CM equivalent
Converter →- 006.5Amebic brain abscessexact
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about A06.6
Is A06.6 billable?
- Yes. A06.6 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A06.6 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A06.6 as a principal diagnosis.
Is A06.6 a CC or MCC?
- A06.6 is an MCC (major complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.
What DRG does A06.6 group to?
- A06.6 is used in the MS-DRG v44.0 logic for MS-DRG 023 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis with MCC or Antineoplastic Implant or Epilepsy with Neurostimulator), MS-DRG 024 (Craniotomy with Major Device Implant or Acute Complex CNS Principal Diagnosis without MCC), MS-DRG 097 (Non-Bacterial Infection of Nervous System Except Viral Meningitis with MCC), MS-DRG 098 (Non-Bacterial Infection of Nervous System Except Viral Meningitis with CC) and MS-DRG 099 (Non-Bacterial Infection of Nervous System Except Viral Meningitis without CC/MCC). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for A06.6?
- The CMS General Equivalence Mappings map A06.6 to ICD-9-CM 006.5.