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  6. 2024 ICD-10-CM Code A49

2024 ICD-10-CM Diagnosis Code A49

Bacterial infection of unspecified site

ICD-10-CM Code:
A49
ICD-10 Code for:
Bacterial infection of unspecified site
Is Billable?
Not Valid for Submission
Code Navigator:

Code Classification

  • Certain infectious and parasitic diseases
    (A00–B99)
    • Other bacterial diseases
      (A30-A49)
      • Bacterial infection of unspecified site
        (A49)

A49 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of bacterial infection of unspecified site. The code is not specific and is NOT valid for the year 2024 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Unspecified diagnosis codes like A49 are acceptable when clinical information is unknown or not available about a particular condition. Although a more specific code is preferable, unspecified codes should be used when such codes most accurately reflect what is known about a patient's condition. Specific diagnosis codes should not be used if not supported by the patient's medical record.

Specific Coding Applicable to Bacterial infection of unspecified site

Non-specific codes like A49 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for bacterial infection of unspecified site:

  • A49.0 for Staphylococcal infection, unspecified site - NON-BILLABLE CODE

  • Use A49.01 for Methicillin susceptible Staphylococcus aureus infection, unspecified site - BILLABLE CODE

  • Use A49.02 for Methicillin resistant Staphylococcus aureus infection, unspecified site - BILLABLE CODE

  • Use A49.1 for Streptococcal infection, unspecified site - BILLABLE CODE

  • Use A49.2 for Hemophilus influenzae infection, unspecified site - BILLABLE CODE

  • Use A49.3 for Mycoplasma infection, unspecified site - BILLABLE CODE

  • Use A49.8 for Other bacterial infections of unspecified site - BILLABLE CODE

  • Use A49.9 for Bacterial infection, unspecified - BILLABLE CODE

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Type 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
  • bacterial agents as the cause of diseases classified elsewhere B95 B96
  • chlamydial infection NOS A74.9
  • meningococcal infection NOS A39.9
  • rickettsial infection NOS A79.9
  • spirochetal infection NOS A69.9

Patient Education


Bacterial Infections

Bacteria are living things that have only one cell. Under a microscope, they look like balls, rods, or spirals. They are so small that a line of 1,000 could fit across a pencil eraser. Most types of don't make you sick. Many types are helpful. Some of them help to digest food, destroy disease-causing cells, and give the body needed vitamins. Bacteria are also used in making healthy foods like yogurt and cheese.

But infectious bacteria can make you ill. They reproduce quickly in your body. Many give off chemicals called toxins, which can damage tissue and make you sick. Examples of bacteria that cause infections include Streptococcus, Staphylococcus, and E. coli.

Antibiotics are the usual treatment. When you take antibiotics, follow the directions carefully. Each time you take antibiotics, you increase the chances that bacteria in your body will learn to resist them causing antibiotic resistance. Later, you could get or spread an infection that those antibiotics cannot cure.

NIH: National Institute of Allergy and Infectious Diseases


[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.