2021 ICD-10-CM Code M00.9

Pyogenic arthritis, unspecified

Version 2021
Billable Code
Unspecified Code
MS-DRG Mapping

Valid for Submission

M00.9 is a billable diagnosis code used to specify a medical diagnosis of pyogenic arthritis, unspecified. The code M00.9 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 M00.9 might also be used to specify conditions or terms like acute bacterial arthritis, acute infective arthritis, acute infective arthritis, acute infective polyarthritis, acute polyarthritis , acute suppurative arthritis, etc.

Unspecified diagnosis codes like M00.9 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.

ICD-10:M00.9
Short Description:Pyogenic arthritis, unspecified
Long Description:Pyogenic arthritis, unspecified

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 M00.9:


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 M00.9 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 M00.9 to ICD-9 Code

The General Equivalency Mapping (GEM) crosswalk indicates an approximate mapping between the ICD-10 code M00.9 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


Infectious Arthritis

Also called: Septic arthritis

Most kinds of arthritis cause pain and swelling in your joints. Joints are places where two bones meet, such as your elbow or knee. Infectious arthritis is an infection in the joint. The infection comes from a bacterial, viral, or fungal infection that spreads from another part of the body. Symptoms of infectious arthritis include

One type of infectious arthritis is reactive arthritis. The reaction is to an infection somewhere else in your body. The joint is usually the knee, ankle, or toe. Sometimes, reactive arthritis is set off by an infection in the bladder, or in the urethra, which carries urine out of the body. In women, an infection in the vagina can cause the reaction. For both men and women, it can start with bacteria passed on during sex. Another form of reactive arthritis starts with eating food or handling something that has bacteria on it.

To diagnose infectious arthritis, your health care provider may do tests of your blood, urine, and joint fluid. Treatment includes medicines and sometimes surgery.


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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)