2023 ICD-10-CM Diagnosis Code A31.9

Mycobacterial infection, unspecified

    2016 2017 2018 2019 2020 2021 2022 2023 Billable/Specific Code
  • A31.9 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2023 edition of ICD-10-CM A31.9 became effective on October 1, 2022.
  • This is the American ICD-10-CM version of A31.9 - other international versions of ICD-10 A31.9 may differ.
Applicable To
  • Atypical mycobacterial infection NOS
  • Mycobacteriosis NOS
The following code(s) above A31.9 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to A31.9:
  • A00-B99
    2023 ICD-10-CM Range A00-B99

    Certain infectious and parasitic diseases

    • diseases generally recognized as communicable or transmissible
    Type 1 Excludes
    • certain localized infections - see body system-related chapters
    Type 2 Excludes
    • carrier or suspected carrier of infectious disease (Z22.-)
    • 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 to identify resistance to antimicrobial drugs (Z16.-)
    Certain infectious and parasitic diseases
  • A31
    ICD-10-CM Diagnosis Code A31

    Infection due to other mycobacteria

      2016 2017 2018 2019 2020 2021 2022 2023 Non-Billable/Non-Specific Code
    Type 2 Excludes
    Infection due to other mycobacteria
Approximate Synonyms
  • Atypical mycobacterial infection
  • Atypical mycobacterial infection of hand
  • Bilateral mycobacterial keratitis
  • Keratitis, mycobacteria
  • Left mycobacterial keratitis
  • Mycobacteria, hand, atypical
  • Mycobacterial infection
  • Mycobacterial infection, atypical
  • Mycobacterial keratitis
  • Mycobacteriosis
  • Right mycobacterial keratitis
Clinical Information
  • Infections with bacteria of the genus mycobacterium.
  • Infections with nontuberculous mycobacteria (atypical mycobacteria): m. Kansasii, m. Marinum, m. Scrofulaceum, m. Flavescens, m. Gordonae, m. Obuense, m. Gilvum, m. Duvali, m. Szulgai, m. Intracellulare (see mycobacterium avium complex;), m. Xenopi (littorale), m. Ulcerans, m. Buruli, m. Terrae, m. Fortuitum (minetti, giae), m. Chelonae.
  • 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. But they can still harm people, especially people with other problems that affect their immunity, such as aids.sometimes you can have these infections with no symptoms at all. At other times, they can cause lung symptoms similar to tuberculosis:
    • cough
    • weight loss
    • coughing up blood or mucus
    • weakness or fatigue
    • fever and chills
    • night sweats
    • lack of appetite and weight loss
    medicines can treat these infections, but often more than one is needed to cure the infection.
ICD-10-CM A31.9 is grouped within Diagnostic Related Group(s) (MS-DRG v40.0):
  • 867 Other infectious and parasitic diseases diagnoses with mcc
  • 868 Other infectious and parasitic diseases diagnoses with cc
  • 869 Other infectious and parasitic diseases diagnoses without cc/mcc
  • 974 Hiv with major related condition with mcc
  • 975 Hiv with major related condition with cc
  • 976 Hiv with major related condition without cc/mcc

Convert A31.9 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
  • 2021 (effective 10/1/2020): No change
  • 2022 (effective 10/1/2021): No change
  • 2023 (effective 10/1/2022): No change

Diagnosis Index entries containing back-references to A31.9:
  • Disease, diseased - see also Syndrome
    • photochromogenic (acid-fast bacilli) (pulmonary) A31.0
      ICD-10-CM Diagnosis Code A31.0

      Pulmonary mycobacterial infection

        2016 2017 2018 2019 2020 2021 2022 2023 Billable/Specific Code
      Applicable To
      • Infection due to Mycobacterium avium
      • Infection due to Mycobacterium intracellulare [Battey bacillus]
      • Infection due to Mycobacterium kansasii
      • nonpulmonary A31.9
  • Mycobacterium, mycobacterial (infection) A31.9

ICD-10-CM Codes Adjacent To A31.9
A30.3 Borderline leprosy
A30.4 Borderline lepromatous leprosy
A30.5 Lepromatous leprosy
A30.8 Other forms of leprosy
A30.9 Leprosy, unspecified
A31 Infection due to other mycobacteria
A31.0 Pulmonary mycobacterial infection
A31.1 Cutaneous mycobacterial infection
A31.2 Disseminated mycobacterium avium-intracellulare complex (DMAC)
A31.8 Other mycobacterial infections
A31.9 Mycobacterial infection, unspecified
A32 Listeriosis
A32.0 Cutaneous listeriosis
A32.1 Listerial meningitis and meningoencephalitis
A32.11 Listerial meningitis
A32.12 Listerial meningoencephalitis
A32.7 Listerial sepsis
A32.8 Other forms of listeriosis
A32.81 Oculoglandular listeriosis
A32.82 Listerial endocarditis
A32.89 Other forms of listeriosis

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.