ICD-10-CM 2027 diagnosis code
A49.3Mycoplasma infection, unspecified site
A49.3 is a valid, billable ICD-10-CM code for mycoplasma infection, unspecified site. 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 A49.3
A49.3 is the ICD-10-CM diagnosis code for mycoplasma infection, unspecified site. It belongs to category A49 (bacterial infection of unspecified site), block A30-A49 (other bacterial 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 A49, choose A49.3 (Mycoplasma infection, unspecified site) only when documentation doesn't support a more specific option: staphylococcal infection, unspecified site (A49.0), streptococcal infection, unspecified site (A49.1), hemophilus influenzae infection, unspecified site (A49.2), other bacterial infections of unspecified site (A49.8) and bacterial infection, unspecified (A49.9).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC, relative weight 2.1859), DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC, relative weight 1.0235) and DRG 869 (Other Infectious and Parasitic Diseases Diagnoses without CC/MCC, relative weight 0.6787), in MDC 18 (Infectious and Parasitic Diseases, Systemic or Unspecified Sites), 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 041.81 (other specified bacterial infections in conditions classified elsewhere and of unspecified site, mycoplasma).
Notes that apply from higher levels
Instructions written at a parent level also apply to A49.3.
Broader instructions also apply from Chapter 1: Certain infectious and parasitic diseases.
Alphabetic index entries
2 entriesTerms in the official ICD-10-CM index that lead to A49.3.
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 18 · Infectious and Parasitic Diseases, Systemic or Unspecified Sites
ICD-9-CM equivalent
Converter →- 041.81Other specified bacterial infections in conditions classified elsewhere and of unspecified site, mycoplasmaapproximate
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 A49.3
Is A49.3 billable?
- Yes. A49.3 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can A49.3 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict A49.3 as a principal diagnosis.
Is A49.3 a CC or MCC?
- No. A49.3 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does A49.3 group to?
- A49.3 is used in the MS-DRG v44.0 logic for MS-DRG 867 (Other Infectious and Parasitic Diseases Diagnoses with MCC), MS-DRG 868 (Other Infectious and Parasitic Diseases Diagnoses with CC) and MS-DRG 869 (Other Infectious and Parasitic Diseases Diagnoses 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 A49.3?
- The CMS General Equivalence Mappings map A49.3 to ICD-9-CM 041.81.