2026 ICD-10-CM Diagnosis Code A06.5Amebic lung abscess
ICD-10-CM Codes›A00–B99›A00-A09›A06
- Billable — Valid for Submission
- MCC — Major Complication or Comorbidity
- Risk Adjusts — HCC 283
- Not Chronic
A06.5 is a billable ICD-10-CM diagnosis code for amebic lung abscess. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 177 through 179. 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 4 closely related codes. Coders also document this condition as abscess caused by Entamoeba histolytica. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified lower respiratory disease; and Parasitic, other specified and unspecified infections.
For Medicare Advantage risk adjustment, A06.5 maps to CMS-HCC Category 283 (Empyema, Lung Abscess) under the V28 model, adding a risk factor of about 0.204 for a community, non-dual, aged beneficiary in payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
A06.5 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2026.
Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abscess caused by Entamoeba histolytica
- Abscess of lung
- Amebic lung abscess
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Inclusion Terms
- Amebic abscess of lung (and liver)
These terms are the conditions for which that code is to be used. The terms may be synonyms of the code title, or, in the case of "other specified" codes, the terms are a list of the various conditions assigned to that code. The inclusion terms are not necessarily exhaustive. Additional terms found only in the Alphabetic Index may also be assigned to a code.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Amebiasis
infection with any of various amebae. it is an asymptomatic carrier state in most individuals, but diseases ranging from chronic, mild diarrhea to fulminant dysentery may occur.Dysentery, Amebic
dysentery caused by intestinal amebic infection, chiefly with entamoeba histolytica. this condition may be associated with amebic infection of the liver and other distant sites.Liver Abscess, Amebic
single or multiple areas of pus due to infection by any ameboid protozoa (amebiasis). a common form is caused by the ingestion of entamoeba histolytica.Amebiasis|Amoebiasis|Amoebiasis
a parasitic infection of the colon by entamoeba histolytica. signs and symptoms include cramping, diarrhea, bloody stools and fever. it can be treated with antibiotics.Amebiasis
a parasitic infectious disorder caused by amoebas. the parasite may cause colitis which is manifested with bloody diarrhea, abdominal pain, nausea and fever. in rare cases it may spread to the liver, brain and lungs.
Patient EducationClinical
Abscess
An abscess is a pocket of pus. You can get an abscess almost anywhere in your body. When an area of your body becomes infected, your body's immune system tries to fight the infection. White blood cells go to the infected area, collect within the damaged tissue, and cause inflammation. During this process, pus forms.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert A06.5 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About A06.5Overview
What is the ICD-10 code for amebic lung abscess?
The ICD-10-CM code for amebic lung abscess is A06.5 (sometimes written as A065). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is A06.5 (Amebiasis) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report amebic lung abscess on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does A06.5 group to?
When amebic lung abscess is the principal diagnosis on an inpatient stay, it groups to MS-DRG 177, 178, 179, with relative weights from 0.7550 to 1.5627 depending on complications. Higher weights mean higher Medicare reimbursement.
Is A06.5 a CC or MCC?
CMS lists A06.5 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 4 closely related codes in its exclusion list.
What is the ICD-9 equivalent of A06.5?
Under the General Equivalence Mappings, amebic lung abscess converts to ICD-9-CM 006.4 (amebic lung abscess). The mapping is a direct match.
What HCC is A06.5?
A06.5 (amebic lung abscess) maps to CMS-HCC Category 283 (Empyema, Lung Abscess), commonly written as HCC 283, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2026. It mapped to HCC 115 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. It does not map to any RxHCC in the Part D prescription drug model.
Does A06.5 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, A06.5 adds a risk adjustment factor of about 0.204 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.000 to 0.204 depending on the payment segment). A more severe related category (HCC 282) supersedes it when both are reported. See the full factor table on the HCC 283 category page.
