B59 - Pneumocystosis

Version 2023
ICD-10:B59
Short Description:Pneumocystosis
Long Description:Pneumocystosis
Status: Valid for Submission
Version:ICD-10-CM 2023
Code Classification:
  • Certain infectious and parasitic diseases (A00–B99)
    • Protozoal diseases (B50-B64)
      • Pneumocystosis (B59)

B59 is a billable ICD-10 code used to specify a medical diagnosis of pneumocystosis. The code is valid during the fiscal year 2023 from October 01, 2022 through September 30, 2023 for the submission of HIPAA-covered transactions.

Approximate Synonyms

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

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 this diagnosis code:


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 References

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 this diagnosis code are found in the injuries and diseases index:

Convert to ICD-9 Code

Source ICD-10 CodeTarget ICD-9 Code
B59136.3 - Pneumocystosis

Patient Education


Pneumocystis Infections

Pneumocystis jirovecii is a tiny fungus that lives in the lungs of many people. Most people's immune systems keep the fungus under control. But if you have a weakened immune system, the fungus can make you very sick.

The most common type of infection is pneumocystis pneumonia (PCP). PCP once was the major cause of death for people with HIV/AIDS. But now, it is possible to prevent or treat most cases. The key to surviving PCP is early treatment. The first signs of PCP are fever, dry cough, shortness of breath, and fatigue. If you have a weakened immune system and have these symptoms, see your doctor right away.

To diagnose PCP, doctors use a microscope to look for the fungus in a sample of lung fluid or tissue. Treatment is with antibiotics.

There is no vaccine to prevent PCP. Some people who are at high risk of getting PCP may need to take antibiotics to prevent it.


[Learn More in MedlinePlus]

Code History