2021 ICD-10-CM Code A18.4

Tuberculosis of skin and subcutaneous tissue

  1. ICD-10-CM Index
  2. Chapter: A00–B99
  3. Section: A15-A19
  4. Block: A18
  5. A18.4 - Tuberculosis of skin and subcutaneous tissue
Version 2021
Billable Code
MS-DRG Mapping

Valid for Submission

A18.4 is a billable diagnosis code used to specify a medical diagnosis of tuberculosis of skin and subcutaneous tissue. The code A18.4 is valid during the fiscal year 2021 from October 01, 2020 through September 30, 2021 for the submission of HIPAA-covered transactions.

The ICD-10-CM code A18.4 might also be used to specify conditions or terms like acute tuberculous ulcer, bcg-induced lupus vulgaris, bcg-induced scrofuloderma, bcg-induced tuberculide, cutaneous complication of bcg immunization , cutaneous tuberculous gumma, etc.

ICD-10:A18.4
Short Description:Tuberculosis of skin and subcutaneous tissue
Long Description:Tuberculosis of skin and subcutaneous tissue

Code Classification

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 guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code A18.4:


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.

Type 2 Excludes

Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.

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 A18.4 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 A18.4 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code A18.4 its ICD-9 equivalent. The approximate mapping means there is not an exact match between the ICD-10 code and the ICD-9 code and the mapped code is not a precise representation of the original code.

Information for Patients


Skin Infections

What are skin infections?

Your skin is your body's largest organ. It has many different functions, including covering and protecting your body. It helps keep germs out. But sometimes the germs can cause a skin infection. This often happens when there is a break, cut, or wound on your skin. It can also happen when your immune system is weakened, because of another disease or a medical treatment.

Some skin infections cover a small area on the top of your skin. Other infections can go deep into your skin or spread to a larger area.

What causes skin infections?

Skin infections are caused by different kinds of germs. For example,

Who is at risk for skin infections?

You are at a higher risk for a skin infection if you

What are the symptoms of skin infections?

The symptoms depend on the type of infection. Some symptoms that are common to many skin infections include rashes, swelling, redness, pain, pus, and itching.

How are skin infections diagnosed?

To diagnose a skin infection, health care providers will do a physical exam and ask about your symptoms. You may have lab tests, such as a skin culture. This is a test to identify what type of infection you have, using a sample from your skin. Your provider may take the sample by swabbing or scraping your skin, or removing a small piece of skin (biopsy). Sometimes providers use other tests, such as blood tests.

How are skin infections treated?

The treatment depends on the type of infection and how serious it is. Some infections will go away on their own. When you do need treatment, it may include a cream or lotion to put on the skin. Other possible treatments include medicines and a procedure to drain pus.


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Tuberculosis

Also called: TB

Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but they can also damage other parts of the body.

TB spreads through the air when a person with TB of the lungs or throat coughs, sneezes, or talks. If you have been exposed, you should go to your doctor for tests. You are more likely to get TB if you have a weak immune system.

Symptoms of TB in the lungs may include

Skin tests, blood tests, x-rays, and other tests can tell if you have TB. If not treated properly, TB can be deadly. You can usually cure active TB by taking several medicines for a long period of time.

NIH: National Institute of Allergy and Infectious 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)

Previous Code: A18.39

Related Codes

Next Code: A18.5