Skip to content

B40.2

Billable

Pulmonary blastomycosis, unspecified

Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)

Is B40.2 an HCC code?

Yes. B40.2 maps to Pneumococcal Pneumonia, Empyema, Lung Abscess under the V24 model but is not retained in V28.

HCC Category Mapping

V24HCC 115Pneumococcal Pneumonia, Empyema, Lung Abscess
0.130
ESRDHCC 115Pneumococcal Pneumonia/Empyema/Lung Abscess
0.030

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

MEAT Criteria for B40.2

For B40.2to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically — it has to be re-documented and supported each calendar year.

  • MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
  • EEvaluate: test results, medication response, or physical findings reviewed by the provider
  • AAssess: explicit mention in the assessment or plan with acknowledgment of status
  • TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed B40.2 during that encounter — not just copy-forwarded from a problem list.

What This Code Means

B40.2 is the ICD-10-CM diagnosis code for pulmonary blastomycosis, unspecified. A fungal infection affecting the lungs caused by Blastomyces, a fungus found in soil and decaying wood, typically acquired through inhalation. B40.2 sits in the ICD-10-CM chapter for certain infectious and parasitic diseases (a00-b99), within the section covering mycoses (b35-b49).

Under the older CMS-HCC V24 model, B40.2 maps to Pneumococcal Pneumonia, Empyema, Lung Abscess (HCC 115) with a community, non-dual, aged base RAF weight of 0.130. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

Specify the type of pulmonary involvement if documented (acute, chronic, or progressive). Because B40.2 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for B40.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • Specify the type of pulmonary involvement if documented (acute, chronic, or progressive)
  • Distinguish from other forms of blastomycosis affecting different body systems

Clinical Significance

Pulmonary blastomycosis, unspecified, captures confirmed pulmonary Blastomyces infection when the documentation does not specify acute or chronic course. This code signals an opportunity for provider query to improve documentation specificity and coding accuracy.

Documentation Requirements

  • Confirmed Blastomyces infection via culture, antigen, or histopathology
  • Documented pulmonary involvement through imaging or respiratory symptoms
  • Provider query attempted regarding acute versus chronic course
  • Treatment regimen documented (itraconazole for mild-moderate, amphotericin B for severe)
  • Epidemiologic exposure history

Commonly Confused Codes

  • B40.0 (Acute pulmonary blastomycosis) - use when acute onset is clearly documented
  • B40.1 (Chronic pulmonary blastomycosis) - use when chronic progressive course is documented
  • B40.3 (Cutaneous blastomycosis) - skin involvement is coded separately from pulmonary disease

Code Hierarchy

B40BlastomycosisB40.2Pulmonary blastomycosis, unspecified
B40.2Pulmonary blastomycosis, unspecified

Open B40.2 in the Interactive Encoder

See full code details, AI coding tips, HCC mappings, and related codes in our interactive encoder. Start your 14-day Pro trial — no credit card required.