Skip to content
HCC Buddy home

FY2027 ICD-10-CM reference

B59: Pneumocystosis

By the HCC Buddy Coding Team

The official ICD-10-CM descriptor is Pneumocystosis. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.

Billable code. Verified against the official FY2027 order file.

Oct to Dec 2026, PY2027

CMS-HCC V28

Mapped
  • HCC 6Opportunistic InfectionsCoefficient 0.381 (CNA, PY2027)

CMS-HCC V24

Not used by CMS

ESRD

Mapped
  • HCC 6Opportunistic InfectionsCoefficient 0.076 (Dialysis CE, PY2027)

RxHCC

Mapped
  • HCC 5Opportunistic InfectionsCoefficient 0.603 (MA-PD CE non-low aged, PY2027)

PACE (CMS-HCC V22 component)

Mapped
  • HCC 6Opportunistic Infections

PACE ESRD (ESRD V21 component)

Mapped
  • HCC 6Opportunistic Infections

PACE RxHCC (2018/2019 component)

Mapped
  • HCC 5Opportunistic Infections

Jan to Sep 2027, PY2028

CMS-HCC V28

Not published by CMS

CMS-HCC V24

Not published by CMS

ESRD

Not published by CMS

RxHCC

Not published by CMS

PACE (CMS-HCC V22 component)

Not published by CMS

PACE ESRD (ESRD V21 component)

Not published by CMS

PACE RxHCC component

Not published by CMS

Oct to Dec 2026, BY2026

HHS-HCC

Pending

Jan to Sep 2027, BY2027

HHS-HCC

Not published by CMS

FY2027 Tabular instructions

Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.

Includes

diseases generally recognized as communicable or transmissible

Source: A00-B99 (chapter, inherited).

Instructional note

code to identify resistance to antimicrobial drugs (Z16.-)

Source: A00-B99 (chapter, inherited).

Excludes2

carrier or suspected carrier of infectious disease (Z22.-)

Source: A00-B99 (chapter, inherited).

Excludes2

certain localized infections - see body system-related chapters

Source: A00-B99 (chapter, inherited).

Excludes2

infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)

Source: A00-B99 (chapter, inherited).

Excludes2

infectious and parasitic diseases specific to the perinatal period (P35-P39)

Source: A00-B99 (chapter, inherited).

Excludes2

influenza and other acute respiratory infections (J00-J22)

Source: A00-B99 (chapter, inherited).

Excludes1

amebiasis (A06.-)

Source: B50-B64 (section, inherited).

Excludes1

other protozoal intestinal diseases (A07.-)

Source: B50-B64 (section, inherited).

Instructional note

Pneumonia due to Pneumocystis carinii

Source: B59 (category, direct).

Instructional note

Pneumonia due to Pneumocystis jirovecii

Source: B59 (category, direct).

Source: CMS FY2027 Tabular List and Alphabetic Index.

Open Tabular instructions and code details

Compare the FY2027 additions, removals and billable-status changes

What does B59 mean in FY2027?

The official ICD-10-CM descriptor is Pneumocystosis. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.

Is B59 billable in FY2027?

The FY2027 order file marks B59 as billable. Check the complete Tabular instructions and documentation before assigning it.

Does B59 map to an HCC?

Oct to Dec 2026, PY2027: CMS-HCC V28 HCC 6 (Opportunistic Infections); CMS-HCC V24: Not used by CMS; ESRD HCC 6 (Opportunistic Infections); RxHCC HCC 5 (Opportunistic Infections). Jan to Sep 2027, PY2028: CMS-HCC V28: Not published by CMS; CMS-HCC V24: Not published by CMS; ESRD: Not published by CMS; RxHCC: Not published by CMS. Oct to Dec 2026, BY2026: HHS-HCC: Pending. Jan to Sep 2027, BY2027: HHS-HCC: Not published by CMS. Base coefficients are reference values, not a member total.

Source: CMS FY2027 ICD-10-CM order file. Payment model: CMS CY 2027 Rate Announcement. Read the FY2027 Official Guidelines.

Review the FY2026 April edition