E43
BillableUnspecified severe protein-calorie malnutrition
Last updated: FY2026 ICD-10-CM (Oct 1, 2025 – Sep 30, 2026) | CMS-HCC V28 (100% phase-in, PY2026)
Is E43 an HCC code?
Yes. E43 maps to Protein-Calorie Malnutrition under the V24 model but is not retained in V28.
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 E43
For E43to 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 E43 during that encounter — not just copy-forwarded from a problem list.
What This Code Means
E43 is the ICD-10-CM diagnosis code for unspecified severe protein-calorie malnutrition. Severe malnutrition due to inadequate protein and calories when the specific type (kwashiorkor vs. marasmus) cannot be determined. E43 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering malnutrition (e40-e46).
Under the older CMS-HCC V24 model, E43 maps to Protein-Calorie Malnutrition (HCC 21) with a community, non-dual, aged base RAF weight of 0.545. 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.
Use this code when documentation doesn't clearly distinguish between kwashiorkor and marasmus. Because E43 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 E43 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
Clinical Significance
Unspecified severe protein-calorie malnutrition indicates that a patient has documented severe malnutrition but the clinical picture does not clearly distinguish between kwashiorkor and marasmus, or the provider has not specified the type. This still represents a life-threatening nutritional state requiring urgent medical intervention and careful refeeding to avoid refeeding syndrome.
Documentation Requirements
- ✓Documentation should include evidence of severe malnutrition such as body mass index below 16, severe muscle wasting, laboratory markers (albumin below 2.5 g/dL, prealbumin below 5 mg/dL), and functional impairment.
- ✓The provider should attempt to specify whether edema is present (suggesting kwashiorkor) or absent (suggesting marasmus) for more specific coding.
- ✓Underlying cause and treatment plan must be documented.
Commonly Confused Codes
- •E40 (Kwashiorkor), E41 (Nutritional marasmus), and E42 (Marasmic kwashiorkor) are preferred when the type can be determined.
- •E44.0 (Moderate protein-calorie malnutrition) and E44.1 (Mild protein-calorie malnutrition) indicate less severe forms.
- •E46 (Unspecified protein-calorie malnutrition) does not specify severity.
- •Query the provider to determine if E40-E42 can be assigned instead.