2027 ICD-10-CM Diagnosis Code A31.2Disseminated mycobacterium avium-intracellulare complex (DMAC)
ICD-10-CM Codes›A00–B99›A30-A49›A31
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Risk Adjusts — HCC 6
- Not Chronic
A31.2 is a billable ICD-10-CM diagnosis code for disseminated mycobacterium avium-intracellulare complex (DMAC). It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 867 through 869, 974 through 976. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 5 closely related codes. Coders also document this condition as disseminated atypical mycobacterial infection. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Bacterial infections.
For Medicare Advantage risk adjustment, A31.2 maps to CMS-HCC Category 6 (Opportunistic Infections) under the V28 model, adding a risk factor of about 0.381 for a community, non-dual, aged beneficiary in payment year 2027.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
A31.2 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 2027.
Source: CMS Payment Year 2027 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.
- Disseminated atypical mycobacterial infection
- Disseminated infection caused by Mycobacterium avium-intracellulare group
- Infection caused by Mycobacterium avium-intracellulare group
- Recurrent infection caused by Mycobacterium
- Recurrent infection caused by Mycobacterium avium complex
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to A31.2: its own notes plus those printed at A31 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- diseases generally recognized as communicable or transmissible
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- MAC sepsis
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- carrier or suspected carrier of infectious disease (Z22.-)
- certain localized infections - see body system-related chapters
- infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
- infectious and parasitic diseases specific to the perinatal period (P35-P39)
- influenza and other acute respiratory infections (J00-J22)
Use Additional Code
Add a second code, after this one, to fully describe the condition.
- code to identify resistance to antimicrobial drugs (Z16.-)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
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.
Patient EducationClinical
Mycobacterial Infections
Mycobacteria are a type of germ. There are many different kinds. The most common one causes tuberculosis. Another one causes leprosy. Still others cause infections that are called atypical mycobacterial infections. They aren't "typical" because they don't cause tuberculosis.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert A31.2 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About A31.2Overview
What is the ICD-10 code for disseminated mycobacterium avium-intracellulare complex (DMAC)?
The ICD-10-CM code for disseminated mycobacterium avium-intracellulare complex (DMAC) is A31.2 (sometimes written as A312). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is A31.2 (Infection due to other mycobacteria) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report disseminated mycobacterium avium-intracellulare complex (DMAC) on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does A31.2 group to?
When disseminated mycobacterium avium-intracellulare complex (DMAC) is the principal diagnosis on an inpatient stay, it groups to MS-DRG 974, 976, 975, 867, 869, 868, with relative weights from 0.6784 to 3.0488 depending on complications. Higher weights mean higher Medicare reimbursement.
Is A31.2 a CC or MCC?
CMS lists A31.2 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 5 closely related codes in its exclusion list.
What is the ICD-9 equivalent of A31.2?
Under the General Equivalence Mappings, disseminated mycobacterium avium-intracellulare complex (DMAC) converts to ICD-9-CM 031.2 (DMAC bacteremia). The mapping is a direct match.
What HCC is A31.2?
A31.2 (disseminated mycobacterium avium-intracellulare complex (DMAC)) maps to CMS-HCC Category 6 (Opportunistic Infections), commonly written as HCC 6, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 6 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 5.
Does A31.2 risk-adjust for Medicare Advantage payment?
Yes. When documented and reported on a Medicare Advantage encounter, A31.2 adds a risk adjustment factor of about 0.381 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.381 to 0.833 depending on the payment segment). HCC 6 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 6 category page.
