Z48.24
BillableEncounter for aftercare following lung transplant
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is Z48.24 an HCC code?
Yes. Z48.24 maps to Lung Transplant Status/Complications under the CMS-HCC V28 risk adjustment model (and Major Organ Transplant or Replacement Status under V24).
HCC Category Mapping
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 Z48.24
For Z48.24to 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 Z48.24 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
Z48.24 is the ICD-10-CM diagnosis code for encounter for aftercare following lung transplant. A follow-up visit for ongoing care and monitoring after receiving a lung transplant. Z48.24 sits in the ICD-10-CM chapter for factors influencing health status and contact with health services (z00-z99), within the section covering encounters for other specific health care (z40-z53).
Under the CMS-HCC V28 risk adjustment model, Z48.24 maps to Lung Transplant Status/Complications (HCC 276) with a community, non-dual, aged base RAF weight of 0.193. Under the older CMS-HCC V24 model, Z48.24 maps to Major Organ Transplant or Replacement Status (HCC 186) with a community, non-dual, aged base RAF weight of 0.910. 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.
Appropriate for routine surveillance and pulmonary function testing. Because Z48.24 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 Z48.24 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Appropriate for routine surveillance and pulmonary function testing
- •Distinguish from acute rejection or infection codes if those conditions are present
Clinical Significance
This code indicates ongoing post-transplant care for lung transplant recipients, representing patients with the highest complexity medical needs requiring intensive monitoring and specialized management. Lung transplant aftercare involves immunosuppression management, rejection surveillance, and monitoring for complications.
Documentation Requirements
- ✓Clear documentation of lung transplant history
- ✓Specific mention of aftercare or follow-up purpose
- ✓Post-transplant monitoring activities performed
- ✓Assessment of transplant function (pulmonary function tests, imaging)
- ✓Immunosuppressive medication management
- ✓Provider specialty (transplant team, pulmonology)
- ✓Time interval since transplantation
- ✓Any rejection episodes or complications noted
Commonly Confused Codes
- •Z94.2 — Use for lung transplant status without active aftercare encounter
- •Z48.21 — Use for heart transplant aftercare instead of lung
- •Z48.22 — Use for kidney transplant aftercare instead of lung
- •T86.810 — Use when documenting lung transplant complications/rejection
- •J44.1 — Use for COPD exacerbation, not transplant aftercare