2027 ICD-10-CM Diagnosis Code E46Unspecified protein-calorie malnutrition

ICD-10-CM Codes›E00–E89›E40-E46›E46

ICD-10-CM E46
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

E46 is a billable ICD-10-CM diagnosis code for unspecified protein-calorie malnutrition. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 640 through 641, 791, 793. 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 9 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Malnutrition.

E46 no longer risk-adjusts for Medicare Advantage: it mapped to HCC 21 under the retired CMS-HCC V24 model through payment year 2025 but maps to no category in the live V28 model. It still risk-adjusts in the PACE (CMS-HCC V22) category 21, ESRD (V21) category 21, and ESRD (V24) category 21 for payment year 2027.

Code Identity

ICD-10-CM Code
E46
Billable Status
Yes — Valid for Submission
Code Describes
Unspecified protein-calorie malnutrition
Short Description
Unspecified protein-calorie malnutrition
Same as the full description in the CMS dataset.
Chapter
E40-E46
Malnutrition

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE40-E46Malnutrition
CategoryE46Unspecified protein-calorie malnutrition
This CodeE46Unspecified protein-calorie malnutrition

Medicare Risk Adjustment (HCC)Billing

E46 no longer risk-adjusts for Medicare Advantage: it maps to no payment category in the live CMS-HCC V28 model, although it still risk-adjusts in the other CMS models shown below.

CMS-HCC V28 (Medicare Advantage Payment Model)
Not mapped
Dropped in V28 see all codes that no longer risk-adjust
Prior Model (CMS-HCC V24)
HCC 21
V24 retired last contributed to a Medicare Advantage risk score in payment year 2025
Other CMS Models
PACE (CMS-HCC V22): HCC 21 · ESRD (V21): HCC 21 · ESRD (V24): HCC 21
ESRD V21 weights: 0.055 dialysis, 0.252–0.593 functioning graft · ESRD V24 weights: 0.068 dialysis, 0.326–0.963 functioning graft
Part D (RxHCC)
Not mapped
E46 does not risk-adjust in the RxHCC prescription drug model

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.

  • Acute disease or injury-related malnutrition
  • Acute malnutrition in adolescence
  • Acute malnutrition in childhood
  • Acute malnutrition in infancy
  • Cataract due to undernutrition
  • Cataract in systemic disorders
  • Child neglect
  • Chronic disease-related malnutrition
  • Coma due to malnutrition-related diabetes mellitus
  • Deficiency of macronutrients
  • Diabetes mellitus associated with pancreatic disease
  • Diabetic ketoacidosis
  • Disorder due to malnutrition related diabetes mellitus
  • Disorder of eye due to malnutrition related diabetes mellitus
  • Disorder of nervous system due to malnutrition related diabetes mellitus
  • Disorder of vision due to secondary diabetes mellitus
  • Fibrocalculous pancreatic diabetes
  • Generalized redundant skin due to malnutrition
  • Gingival disease due to malnutrition
  • Hair changes due to malnutrition
  • Hypertrichosis in malnutrition
  • Hypoalbuminemia
  • Hypoalbuminemia due to protein calorie malnutrition
  • Hypoproteinemia
  • Inadequate intake of energy
  • Inadequate intake of protein and/or protein derivative
  • Ketoacidosis due to secondary diabetes mellitus
  • Malnutrition
  • Malnutrition due to child maltreatment
  • Malnutrition related diabetes mellitus
  • Malnutrition-dehydration cataract
  • Malnutrition-related diabetes mellitus - fibrocalculous
  • Malnutrition-related diabetes mellitus with ketoacidosis
  • Nutritional hair color change
  • Nutritional maltreatment of child
  • Nutritional myopathy
  • Nutritionally compromised
  • Peripheral circulatory disorder due to malnutrition-related diabetes mellitus
  • Peripheral vascular disease due to secondary diabetes mellitus
  • Peripheral vascular disorder due to diabetes mellitus
  • Pre-existing diabetes mellitus in pregnancy
  • Pre-existing malnutrition-related diabetes mellitus
  • Pre-existing malnutrition-related diabetes mellitus in pregnancy
  • Protein deficiency disease
  • Protein deficiency myopathy
  • Protein-deficient diabetes mellitus
  • Redundant skin
  • Skin changes due to malnutrition
  • Starvation-related malnutrition
  • Undernutrition

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to E46: its own notes plus those printed at block E40-E46 and Chapter 4. A note printed at a category, block or chapter applies to every code under it.

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.

  • Malnutrition NOS
  • Protein-calorie imbalance NOS

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

On E46 itself
  • nutritional deficiency NOS (E63.9)
From Block E40-E46 Malnutrition applies to 8 codes
  • intestinal malabsorption (K90.-)
  • sequelae of protein-calorie malnutrition (E64.0)
From Chapter 4 (E00-E89) Endocrine, nutritional and metabolic diseases applies to 973 codes
  • transitory endocrine and metabolic disorders specific to newborn (P70-P74)

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 E40-E46 Malnutrition applies to 8 codes

Notes

General instructions on how these codes are used.

From Chapter 4 (E00-E89) Endocrine, nutritional and metabolic diseases applies to 973 codes
  • All neoplasms, whether functionally active or not, are classified in Chapter 2. Appropriate codes in this chapter (i.e. E05.8, E07.0, E16-E31, E34.-) may be used as additional codes to indicate either functional activity by neoplasms and ectopic endocrine tissue or hyperfunction and hypofunction of endocrine glands associated with neoplasms and other conditions classified elsewhere.

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

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name E46, its category, or a range that includes it.

Applicable To 1

These notes mention E46.

  • P00.4 Newborn affected by maternal nutritional disorders
    Newborn affected by maternal disorders classifiable to E40-E64 names E40-E64, which includes this code

Excludes1 2

These codes carry an Excludes1 note naming E46: they are not reported together with it, unless the two conditions are unrelated.

  • R63.6 Underweight
    malnutrition (E40-E46) names E40-E46, which includes this code
  • Z72.4 Inappropriate diet and eating habits
    malnutrition and other nutritional deficiencies (E40-E64) names E40-E64, which includes this code

Excludes2 2

These codes carry an Excludes2 note naming E46: its condition is not part of those codes, and both may be reported when the patient has both.

  • R60.1 Generalized edema
    nutritional edema (E40-E46) names E40-E46, which includes this code
  • Z59.4 Lack of adequate food
    malnutrition (E40-E46) names E40-E46, which includes this code

Code First 3

These codes say to code first a condition named in the note, and E46 is one of the conditions named.

  • E08 Diabetes mellitus due to underlying condition
    malnutrition (E40-E46) names E40-E46, which includes this code
  • G63 Polyneuropathy in diseases classified elsewhere
    nutritional deficiency (E40-E64) names E40-E64, which includes this code
  • H28 Cataract in diseases classified elsewhere
    protein-calorie malnutrition (E40-E46) names E40-E46, which includes this code

Code Also 2

These codes say E46 may also be needed to fully describe the condition. The note gives no sequencing direction.

  • R63.31 Pediatric feeding disorder, acute
    malnutrition (E40-E46) names E40-E46, which includes this code
  • R63.32 Pediatric feeding disorder, chronic
    malnutrition (E40-E46) names E40-E46, which includes this code

Notes 1

These notes mention E46.

  • E64 Sequelae of malnutrition and other nutritional deficiencies
    This category is to be used to indicate conditions in categories E43, E44, E46, E50-E63 as the cause of sequelae, which are themselves classified elsewhere. The 'sequelae' include conditions specified as such; they also include the late effects of diseases classifiable to the above categories if the disease itself is no longer present

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 END008
Malnutrition
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Malnutrition

    an imbalanced nutritional status resulting from insufficient intake of nutrients to meet normal physiological requirement.

Patient EducationClinical

Malnutrition

Malnutrition means that your body isn't getting enough calories or the right balance of nutrients to stay healthy. This can happen if you don't get enough protein, carbohydrates, and fats, eat too much unhealthy food, or don't get the vitamins and minerals your body needs.

The full article covers:

  • What is malnutrition?
  • What are the types of malnutrition?
  • What causes malnutrition?
  • Who is at risk for developing malnutrition?
  • What are the symptoms of malnutrition?
  • How is malnutrition diagnosed?
  • What are the treatments for malnutrition?
  • Can malnutrition be prevented?

Read the full article at MedlinePlus

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

Convert E46 to ICD-9-CMHistory

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

ICD-9-CM
263.8 Protein-cal malnutr NEC
Approximate The match is approximate rather than exact.
ICD-9-CM
263.9 Protein-cal malnutr NOS
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 E46Overview

What is the ICD-10 code for unspecified protein-calorie malnutrition?

The ICD-10-CM code for unspecified protein-calorie malnutrition is E46. It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is E46 (Unspecified protein-calorie malnutrition) a billable code?

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

What MS-DRG does E46 group to?

When unspecified protein-calorie malnutrition is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 641, 640, with relative weights from 0.7864 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Is E46 a CC or MCC?

CMS lists E46 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 9 closely related codes in its exclusion list.

Can E46 be reported with E63.9?

Not as a rule. The Excludes1 note on E46 lists "nutritional deficiency NOS (E63.9)". An Excludes1 note means the excluded code is never reported together with this one; the only exception is when the two conditions are unrelated to each other (Official Guidelines, Section I.A.12.a).

Does E46 risk-adjust for Medicare Advantage payment?

Not for Medicare Advantage. E46 mapped to HCC 21 in the retired CMS-HCC V24 model, which last determined payment in 2025, but it maps to no category in the live V28 model; see all codes that no longer risk-adjust. It still risk-adjusts in the PACE (CMS-HCC V22) category 21 (Protein-Calorie Malnutrition), ESRD (V21) category 21 (Protein-Calorie Malnutrition), and ESRD (V24) category 21 (Protein-Calorie Malnutrition).