2027 ICD-10-CM Diagnosis Code B48.4Penicillosis

ICD-10-CM Codes›A00–B99›B35-B49›B48

ICD-10-CM B48.4
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

B48.4 is a billable ICD-10-CM diagnosis code for penicillosis. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 791, 793, 867 through 869. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 12 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fungal infections.

For Medicare Advantage risk adjustment, B48.4 maps to CMS-HCC Category 6 (Opportunistic Infections) under the V28 model, adding a risk factor of about 0.381 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
B48.4
Billable Status
Yes — Valid for Submission
Code Describes
Penicillosis
Short Description
Penicillosis
Same as the full description in the CMS dataset.
Parent Code
Other mycoses, not elsewhere classified

Code Classification

ChapterA00–B99Certain infectious and parasitic diseases
SectionB35-B49Mycoses
CategoryB48Other mycoses, not elsewhere classified
This CodeB48.4Penicillosis

Medicare Risk Adjustment (HCC)Billing

B48.4 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 6— Opportunistic Infections
Payment HCC · PY 2027 one of 37 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.381
community, non-dual, aged · ranges 0.381–0.833 across segments
Hierarchy
Top of its hierarchy
HCC 6 is not superseded by any other condition category
Prior Model (CMS-HCC V24)
HCC 6
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 6 · ESRD (V21): HCC 6 · ESRD (V24): HCC 6
ESRD V21 weights: 0.052 dialysis, 0.426–0.568 functioning graft · ESRD V24 weights: 0.076 dialysis, 0.364–0.782 functioning graft
Part D (RxHCC)
RxHCC 5 — Opportunistic Infections
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Disseminated infection caused by Talaromyces marneffei
  • Infection caused by Penicillium
  • Infection caused by Penicillium chrysogenum
  • Infection caused by Penicillium citreonigrum
  • Infection caused by Penicillium citrinum
  • Infection caused by Penicillium commune
  • Infection caused by Penicillium crustaceum
  • Infection caused by Penicillium cyclopium
  • Infection caused by Penicillium expansum
  • Infection caused by Penicillium frequentans
  • Infection caused by Penicillium glaucum
  • Infection caused by Penicillium griseofulvum
  • Infection caused by Penicillium islandicum
  • Infection caused by Penicillium mycetomagenum
  • Infection caused by Penicillium oxalicum
  • Infection caused by Penicillium palitans
  • Infection caused by Penicillium puberulum
  • Infection caused by Penicillium purpurogenum
  • Infection caused by Penicillium roqueforte
  • Infection caused by Penicillium rugulosum
  • Infection caused by Penicillium spinulosum
  • Infection caused by Penicillium suberi
  • Infection caused by Penicillium verrucosum
  • Infection caused by Penicillium verruculosum
  • Infection caused by Penicillium viridicatum
  • Infection caused by Talaromyces bacillisporus
  • Infection caused by Talaromyces marneffei

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to B48.4: its own notes plus those printed at block B35-B49 and Chapter 1. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • diseases generally recognized as communicable or transmissible

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Talaromycosis

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Block B35-B49 Mycoses applies to 104 codes
  • hypersensitivity pneumonitis due to organic dust (J67.-)
  • mycosis fungoides (C84.0-)
From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • carrier or suspected carrier of infectious disease (Z22.-)
  • certain localized infections - see body system-related chapters
  • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
  • infectious and parasitic diseases specific to the perinatal period (P35-P39)
  • influenza and other acute respiratory infections (J00-J22)

Use Additional Code

Add a second code, after this one, to fully describe the condition.

From Chapter 1 (A00-B99) Certain infectious and parasitic diseases applies to 1,068 codes
  • code to identify resistance to antimicrobial drugs (Z16.-)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR INF004
Fungal infections
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Fungal Infections

If you have ever had athlete's foot or a yeast infection, you can blame a fungus. A fungus is a primitive organism. Mushrooms, mold and mildew are examples. Fungi live in air, in soil, on plants and in water. Some live in the human body. Only about half of all types of fungi are harmful.

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert B48.4 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
117.3 Aspergillosis
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About B48.4Overview

What is the ICD-10 code for penicillosis?

The ICD-10-CM code for penicillosis is B48.4 (sometimes written as B484). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is B48.4 (Other mycoses, not elsewhere classified) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report penicillosis on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does B48.4 group to?

When penicillosis is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 867, 869, 868, with relative weights from 0.6784 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Is B48.4 a CC or MCC?

CMS lists B48.4 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 12 closely related codes in its exclusion list.

What is the ICD-9 equivalent of B48.4?

Under the General Equivalence Mappings, penicillosis converts to ICD-9-CM 117.3 (aspergillosis). The mapping is approximate, so confirm the match fits the documentation.

What HCC is B48.4?

B48.4 (penicillosis) maps to CMS-HCC Category 6 (Opportunistic Infections), commonly written as HCC 6, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 6 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 5.

Does B48.4 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, B48.4 adds a risk adjustment factor of about 0.381 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.381 to 0.833 depending on the payment segment). HCC 6 sits at the top of its hierarchy, so no other condition category supersedes it. See the full factor table on the HCC 6 category page.