Skip to main content

A06.6 ICD-10-CM Code: Amebic brain abscess

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Coding at a Glance

Tabular directives
2 inclusion terms · 1 Excludes1 · 2 Excludes2

Inpatient Payment Groups (MS-DRG)

Potential MS-DRG participation — not a DRG assignment.

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43, Appendix B.

  • MS-DRG 023 — CRANIOTOMY WITH MAJOR DEVICE IMPLANT OR ACUTE COMPLEX CNS PRINCIPAL DIAGNOSIS WITH MCC OR ANTINEOPLASTIC IMPLANT OR EPILEPSY WITH NEUROSTIMULATOR (MDC 01)
  • MS-DRG 024 — CRANIOTOMY WITH MAJOR DEVICE IMPLANT OR ACUTE COMPLEX CNS PRINCIPAL DIAGNOSIS WITHOUT MCC (MDC 01)
  • MS-DRG 097 — NON-BACTERIAL INFECTION OF NERVOUS SYSTEM EXCEPT VIRAL MENINGITIS WITH MCC (MDC 01)
  • MS-DRG 098 — NON-BACTERIAL INFECTION OF NERVOUS SYSTEM EXCEPT VIRAL MENINGITIS WITH CC (MDC 01)
  • MS-DRG 099 — NON-BACTERIAL INFECTION OF NERVOUS SYSTEM EXCEPT VIRAL MENINGITIS WITHOUT CC/MCC (MDC 01)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for A06.6 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on A06.6 itself; “inherited from” names the category or block whose note applies here.

Includes

Conditions the official ICD-10-CM tabular list includes under this code.

  • infection due to Entamoeba histolytica

Source: inherited from A06

Inclusion Terms

Alternative terms the tabular list files under this code.

  • Amebic abscess of brain (and liver) (and lung)

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Source: inherited from A06

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

Source: inherited from A06

Coder workflow for A06.6

MedCoder structured workflow — derived from this code’s own official record

Before you code A06.6

  1. Check the Excludes1 note: if the documentation supports a condition named there, do not simply proceed with A06.6. Excludes1 conditions are not reported together with this code unless the record shows they are unrelated (Guidelines I.A.12.a).

    See the official tabular notes

Choose the right path

  1. Does the documentation support a condition named in A06.6’s Excludes1 note?
    Yes → Do not simply proceed: review the excluded code. Both are reported only when the record shows the two conditions are unrelated.
    No → Continue.

    ReviewA07

Consider A06.6. Then confirm the code is valid for the date of service in the Verify section.

Documentation check

The provider’s diagnostic statement
Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).
Acuity
Acute or chronic as documented; when both are documented and separate codes exist, both are reported with the acute code first (Guidelines I.B.8).

Official instructions as workflow

  • Excludes1 — check before selecting A06.6(1 note)

    Coding workflow: If the documentation supports a condition named in this note, do not simply proceed with A06.6: the two are not reported together. The one exception is when the record shows the two conditions are unrelated to each other.

    CompareA07

    See the official tabular notes · Guidelines I.A.12.a

  • Excludes2 — not part of A06.6(2 notes)

    Coding workflow: The conditions named in this note are not included in A06.6. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

    CompareB60.1, B60.2

    See the official tabular notes · Guidelines I.A.12.b

Coding decision scenarios

Pattern scenarios for this code’s structure — decision rules, not clinical cases

Documentation: Both the condition A06.6 describes and a condition named in its Excludes1 note are documented for the same encounter.

Coding question: Can both codes be reported?

Path: Review the Excludes1 note and the excluded code, and look for a provider statement on whether the two conditions are related.

Reason: Excludes1 means the two are not coded together; the exception is when the record shows the conditions are unrelated to each other (Guidelines I.A.12.a).

ReviewA07

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Code Overview

Amebic brain abscess is a billable ICD-10-CM diagnosis code (A06.6).

MedCoder summary Summary composed by MedCoder from this code's official ICD-10-CM record. The tabular instructional notes themselves appear verbatim below.

Indexed Clinical Terms (4)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

Verify Before Coding

  • MCC as a secondary diagnosis (FY2026). Can raise the stay's MS-DRG severity tier.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name A06.6 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 14 Excludes1 notes across 2 chapters: B50 — Plasmodium falciparum malaria (via A06.-), B50-B64 — Protozoal diseases (B50-B64) (via A06.-), B51 — Plasmodium vivax malaria (via A06.-), B52 — Plasmodium malariae malaria (via A06.-), B53 — Other specified malaria (via A06.-), B54 — Unspecified malaria (via A06.-), B55 — Leishmaniasis (via A06.-), B56 — African trypanosomiasis (via A06.-), B57 — Chagas' disease (via A06.-), B58 — Toxoplasmosis (via A06.-), B59 — Pneumocystosis (via A06.-), B60 — Other protozoal diseases, not elsewhere classified (via A06.-), B64 — Unspecified protozoal disease (via A06.-), G07 — Intracranial and intraspinal abscess and granuloma in diseases classified elsewhere.

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

Referenced by 6 Excludes2 notes: P35 — Congenital viral diseases (via A06.-), P35-P39 — Infections specific to the perinatal period (P35-P39) (via A06.-), P36 — Bacterial sepsis of newborn (via A06.-), P37 — Other congenital infectious and parasitic diseases (via A06.-), P38 — Omphalitis of newborn (via A06.-), P39 — Other infections specific to the perinatal period (via A06.-).

These codes’ tabular lists name this diagnosis as distinct — both may be reported when both are documented.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: MCC — Major Complication or Comorbidity. Reported as a secondary diagnosis, this code raises the stay's MS-DRG severity tier — except when the principal diagnosis is one of 2 clinically related codes on its CMS exclusion list.

Named in the grouper logic of 5 MS-DRGs: DRG 023 (MDC 01), DRG 024 (MDC 01), DRG 097 (MDC 01), DRG 098 (MDC 01), DRG 099 (MDC 01).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):NVS014 — CNS abscess (default); INF009 — Parasitic, other specified and unspecified infections.

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same clinical process (MS-DRG)

Acts as MCC — raises the severity of other admissions. CMS groups these diagnoses into one MS-DRG principal-diagnosis exclusion process — a CC/MCC on this list never raises severity when the principal diagnosis is also on it.

G06.0 — Intracranial abscess and granuloma

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical categories (CNS abscess, Parasitic, other specified and unspecified infections).

A06.0 — Acute amebic dysentery, A06.1 — Chronic intestinal amebiasis, A06.2 — Amebic nondysenteric colitis, A06.3 — Ameboma of intestine, A06.4 — Amebic liver abscess, A06.5 — Amebic lung abscess, A06.7 — Cutaneous amebiasis, A06.81 — Amebic cystitis, A06.82 — Other amebic genitourinary infections, A06.89 — Other amebic infections, A06.9 — Amebiasis, unspecified, A07.0 — Balantidiasis, A07.1 — Giardiasis [lambliasis], A07.2 — Cryptosporidiosis, A07.3 — Isosporiasis, A07.4 — Cyclosporiasis, A07.8 — Other specified protozoal intestinal diseases, A07.9 — Protozoal intestinal disease, unspecified, A09 — Infectious gastroenteritis and colitis, unspecified, A17.81 — Tuberculoma of brain and spinal cord, +242 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main term “Abscess”; these codes share that main term but sit in a different category of the Tabular List.

A01.09 — Typhoid fever with other complications (post-typhoid), A17.81 — Tuberculoma of brain and spinal cord (brain, tuberculous), A18.01 — Tuberculosis of spine (spine), A18.2 — Tuberculous peripheral lymphadenopathy (scrofulous), A18.31 — Tuberculous peritonitis (peritoneum, peritoneal, tuberculous), A48.0 — Gas gangrene (anerobic), A50.59 — Other late congenital syphilis, symptomatic (Dubois), A54.1 — Gonococcal infection of lower genitourinary tract with periurethral and accessory gland abscess (penis, gonococcal), A54.22 — Gonococcal prostatitis (prostate, gonococcal), A54.82 — Gonococcal brain abscess (brain, gonococcal), A57 — Chancroid (phagedenic NOS, chancroid), B43.1 — Pheomycotic brain abscess (brain, pheomycotic), B43.2 — Subcutaneous pheomycotic abscess and cyst (subcutaneous, pheomycotic), B65.1 — Schistosomiasis due to Schistosoma mansoni [intestinal schistosomiasis] (bilharziasis), D73.3 — Abscess of spleen (spleen), E06.0 — Acute thyroiditis (thyroid), E23.6 — Other disorders of pituitary gland (pituitary), E27.8 — Other specified disorders of adrenal gland (adrenal), E32.1 — Abscess of thymus (thymus), G06.0 — Intracranial abscess and granuloma (brain), +155 more

Lab tests where this diagnosis supports Medicare coverage (NCD)

Medicare's National Coverage Determination (NCD) program lists this diagnosis as medical justification for these lab tests.

Fecal Occult Blood Test (FOBT), Gamma-glutamyl Transferase (GGT) Test, Iron Panel

Contextual Map

Every relationship of A06.6 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run A06.6 with these 14 related codes in Claim Check

Hierarchy

Referenced by Excludes1 notes (14)

Referenced by Excludes2 notes

Clinical classification (CCSR)

MS-DRG Grouper

MDC crossing

  • MDC 01 — Diseases and Disorders of the Nervous System[MDC crossing]: “Diseases and Disorders of the Nervous System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 8,892 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026

Index entries

  • Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic), amebic, brain (and liver or lung abscess)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic), brain (any part) (cystic) (otogenic), amebic (with abscess of any other site)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • 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)[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
  • Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic), lung (miliary) (putrid), amebic (with liver abscess), with, brain abscess[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026

Nearest codes (13)

Change history

  • FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data
CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page
Claim edits Official source data
CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page
Inpatient payment groups Official source data
CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page
Change history and date-of-service validity Official source data
CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page
Comparisons, relationships and the contextual map MedCoder structured relationship
Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears
Summary and FAQ answers MedCoder explanation
Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Change history

  • FY2016 — October 1, 2015
    In the code set at ICD-10-CM adoption
    Amebic brain abscess

No changes since FY2016 — additions, deletions, description changes and billable-status changes are tracked through FY2027 (effective October 1, 2026), and none are recorded for this code. Note changes are tracked from FY2027 only.

Nearest Codes in This Family

Official ICD-10-CM classifications closest to A06.6 in its code family, with their registry titles.

View all codes in the A06 family