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E46 ICD-10-CM Code: Unspecified protein-calorie malnutrition

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FY 2026 Apr update / Endocrine, nutritional and metabolic diseases (E00-E89) / Malnutrition (E40-E46)

E46

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Unspecified protein-calorie malnutrition

A condition where the body lacks adequate protein and calories, resulting in severe malnutrition and weight loss. The specific cause or type is not documented.

Buddy the Bee presenting code insight

Buddy Insight

Unspecified protein-calorie malnutrition indicates that a patient has documented malnutrition from inadequate protein and calorie intake, but neither the severity (mild, moderate, or severe) nor the type (kwashiorkor vs.

CMS-HCC V28

N/A

—

Not mapped

CMS-HCC V24

HCC 21

RAF 0.455

ACA/HHS

HCC 23

Varies by metal level

ESRD/PACE

HCC 21

RAF 0.068

RXHCC

N/A

—

Not mapped

Code Book Path

Official
E4Malnutrition (E40-E46)
E46Unspecified protein-calorie malnutrition

Inclusion Terms

Official
  • Malnutrition NOS
  • Protein-calorie imbalance NOS

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for E46 in this effective period.

Related Child Codes

Official

ICD-10-CM does not list child codes under E46 for this display context.

Includes

Official

ICD-10-CM does not list Includes notes for E46 in this effective period.

Excludes 1

Official
  • nutritional deficiency NOS (E63.9)

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for E46 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for E46 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for E46 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance
Documentation should include the clinical basis for the malnutrition diagnosis, including body mass index, weight trends, laboratory markers (albumin, prealbumin), physical exam findings, and nutritional screening results.
The provider should be queried to specify severity (mild, moderate, or severe) and type to enable assignment of a more specific code.
The underlying cause and treatment plan should be documented.

MEAT Support

HCC Buddy guidance
Documentation should include the clinical basis for the malnutrition diagnosis, including body mass index, weight trends, laboratory markers (albumin, prealbumin), physical exam findings, and nutritional screening results.
The provider should be queried to specify severity (mild, moderate, or severe) and type to enable assignment of a more specific code.
The underlying cause and treatment plan should be documented.

Audit Caution

HCC Buddy guidance
This is the least specific protein-calorie malnutrition code and should prompt a provider query for severity and type.
Do not assign malnutrition without a provider diagnosis, as coders cannot independently determine malnutrition from lab values alone.
Avoid using this code when documentation clearly supports a more specific malnutrition diagnosis.
In the inpatient setting, ensure malnutrition is reassessed and specified prior to discharge.

Common Mistakes

HCC Buddy guidance
E43 (Unspecified severe protein-calorie malnutrition) specifies severe but not the type.
E44.0 and E44.1 specify moderate and mild severity respectively.
E40-E42 specify both severity and type.
R64 (Cachexia) describes disease-related wasting and is not a malnutrition code.

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is E46 an HCC code?

Yes. E46 maps to Protein-Calorie Malnutrition under the V24 model but is not retained in V28.

Code
E46
Description
Unspecified protein-calorie malnutrition
HCC (V28)
No CMS-HCC V28 mapping
RAF
—
Billable
Yes
Payment year
2026

HCC Category Mapping

V24HCC 21, Protein-Calorie Malnutrition
0.455
ESRDHCC 21, Protein-Calorie Malnutrition
0.068

Each model's RAF is its CMS base weight for that model's standard population, so weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. 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.

Work E46 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for E46

For E46 to 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 E46 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

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What This Code Means

E46 is the ICD-10-CM diagnosis code for unspecified protein-calorie malnutrition. A condition where the body lacks adequate protein and calories, resulting in severe malnutrition and weight loss. The specific cause or type is not documented. E46 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, E46 maps to Protein-Calorie Malnutrition (HCC 21) with a community, non-dual, aged base RAF weight of 0.455. 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.

Unspecified protein-calorie malnutrition, PCM without severity detail. Query the provider to move to E43, E44.0, or E44.1. Because E46 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 E46 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • •Unspecified protein-calorie malnutrition, PCM without severity detail. Query the provider to move to E43, E44.0, or E44.1.
  • •Severity is almost always documentable with a nutritional assessment, unspecified PCM is a query target.
  • •E46 does not map to a V28 payment HCC. Protein-calorie malnutrition is not risk-adjusted in V28; code it accurately for clinical completeness only.

Clinical Significance

Unspecified protein-calorie malnutrition indicates that a patient has documented malnutrition from inadequate protein and calorie intake, but neither the severity (mild, moderate, or severe) nor the type (kwashiorkor vs. marasmus) has been specified. This code signals a documentation opportunity to obtain greater specificity from the provider, which improves clinical care and audit defensibility.

Documentation Requirements

  • ✓Documentation should include the clinical basis for the malnutrition diagnosis, including body mass index, weight trends, laboratory markers (albumin, prealbumin), physical exam findings, and nutritional screening results.
  • ✓The provider should be queried to specify severity (mild, moderate, or severe) and type to enable assignment of a more specific code.
  • ✓The underlying cause and treatment plan should be documented.

Excludes 1, Do NOT code together

  • nutritional deficiency NOS (E63.9)

Commonly Confused Codes

  • •E43 (Unspecified severe protein-calorie malnutrition) specifies severe but not the type.
  • •E44.0 and E44.1 specify moderate and mild severity respectively.
  • •E40-E42 specify both severity and type.
  • •R64 (Cachexia) describes disease-related wasting and is not a malnutrition code.
  • •R63.4 (Abnormal weight loss) is a symptom code.
  • •Z68.x (Body mass index) codes should be added when applicable.

Code Hierarchy

└E46Unspecified protein-calorie malnutrition
└E46Unspecified protein-calorie malnutrition

Because E46 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

More on E46

Related condition guides

Referenced in blog posts

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