2022 ICD-10-CM Code A04.9

Bacterial intestinal infection, unspecified

Version 2021

Valid for Submission

ICD-10:A04.9
Short Description:Bacterial intestinal infection, unspecified
Long Description:Bacterial intestinal infection, unspecified

Code Classification

  • Certain infectious and parasitic diseases (A00–B99)
    • Intestinal infectious diseases (A00-A09)
      • Other bacterial intestinal infections (A04)

A04.9 is a billable diagnosis code used to specify a medical diagnosis of bacterial intestinal infection, unspecified. The code A04.9 is valid during the fiscal year 2022 from October 01, 2021 through September 30, 2022 for the submission of HIPAA-covered transactions.

The ICD-10-CM code A04.9 might also be used to specify conditions or terms like bacterial dysentery, bacterial enteritis, bacterial gastroenteritis, bacterial gastrointestinal infectious disease, bacterial intestinal infectious disease , bacterial overgrowth syndrome, etc.

Unspecified diagnosis codes like A04.9 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.

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code A04.9:


Inclusion Terms

Inclusion Terms
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 Injuries

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for the code A04.9 are found in the index:

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Convert A04.9 to ICD-9 Code

Information for Patients


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 bacteria won't hurt you - less than 1% of the different types make people sick. Many are helpful. Some bacteria 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]

Gastroenteritis

Have you ever had the "stomach flu?" What you probably had was gastroenteritis - not a type of flu at all. Gastroenteritis is an inflammation of the lining of the intestines caused by a virus, bacteria, or parasites. Viral gastroenteritis is the second most common illness in the U.S. The cause is often a norovirus infection. It spreads through contaminated food or water or by contact with an infected person. The best prevention is frequent hand washing.

Symptoms of gastroenteritis include diarrhea, abdominal pain, vomiting, headache, fever, and chills. Most people recover with no treatment.

The most common problem with gastroenteritis is dehydration. This happens if you do not drink enough fluids to replace what you lose through vomiting and diarrhea. Dehydration is most common in babies, young children, older adults, and people with weak immune systems.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


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Code History

  • 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 (First year ICD-10-CM implemented into the HIPAA code set)