2026 ICD-10-CM Diagnosis Code E52Niacin deficiency [pellagra]

ICD-10-CM Codes›E00–E89›E50-E64›E52

ICD-10-CM E52
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E52 is a billable ICD-10-CM diagnosis code for niacin deficiency [pellagra]. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 640 through 641. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nutritional deficiencies.

Code Identity

ICD-10-CM Code
E52
Billable Status
Yes — Valid for Submission
Code Describes
Niacin deficiency [pellagra]
Chapter
E50-E64
Other nutritional deficiencies

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE50-E64Other nutritional deficiencies
CategoryE52Niacin deficiency [pellagra]
This CodeE52Niacin deficiency [pellagra]

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Alcoholic pellagra
  • Deficiency of isocitrate dehydrogenase
  • Dementia due to niacin deficiency
  • Dementia due to nutritional deficiency
  • Dementia due to pellagra
  • Inadequate intake of niacin
  • Niacin deficiency
  • Pellagra
  • Pellagra caused by drug
  • Pellagra neuropathy
  • Polyneuropathy in pellagra
  • Thiamine and niacin deficiency

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Niacin (-tryptophan) deficiency
  • Nicotinamide deficiency
  • Pellagra (alcoholic)

Type 1 Excludes

  • sequelae of niacin deficiency E64.8

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Acid
      • deficiency
        • amide nicotinic
    • Acid
      • deficiency
        • nicotinic
    • Alcohol, alcoholic, alcohol-induced
      • pellagra
    • Avitaminosis(multiple)
      • B
        • with
          • pellagra
    • Avitaminosis(multiple)
      • nicotinic acid
    • Cheilosis(angular)
      • with pellagra
    • Deficiency, deficient
      • niacin (amide) (-tryptophan)
    • Deficiency, deficient
      • nicotinamide
    • Deficiency, deficient
      • nicotinic acid
    • Deficiency, deficient
      • vitamin (multiple) NOS
        • B (complex) NOS
          • with
            • pellagra
    • Deficiency, deficient
      • vitamin (multiple) NOS
        • nicotinic
    • Deficiency, deficient
      • vitamin (multiple) NOS
        • PP (pellagra-preventing)
    • Dementia(degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety)
      • in (due to)
        • niacin deficiency
    • Dementia(degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety)
      • in (due to)
        • niacin deficiency
          • with behavioral disturbance
    • Dementia(degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety)
      • in (due to)
        • pellagra
    • Dementia(degenerative (primary)) (persisting) (unspecified severity) (without behavioral disturbance, psychotic disturbance, mood disturbance, and anxiety)
      • in (due to)
        • pellagra
          • with behavioral disturbance
    • Dermatitis(eczematous)
      • pellagrous
    • Encephalopathy(acute)
      • pellagrous
    • Erythema, erythematous(infectional) (inflammation)
      • endemic
    • Gingivitis
      • pellagrous
    • Glossitis(chronic superficial) (gangrenous) (Moeller's)
      • pellagrous
    • Niacin(amide) deficiency
    • Nicotinic acid deficiency
    • Pellagra(alcoholic)
    • Pellagra(alcoholic)
      • with
        • polyneuropathy
    • Polioencephalopathy, superior hemorrhagic
      • with
        • pellagra
    • Polyneuropathy(peripheral)
      • in (due to)
        • pellagra
    • Syndrome
      • pellagroid

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR END007
Nutritional deficiencies
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Pellagra

    a disease due to deficiency of niacin, a b-complex vitamin, or its precursor tryptophan. it is characterized by scaly dermatitis which is often associated with diarrhea and dementia (the three d's).

Patient EducationClinical

B Vitamins

The B vitamins are:

Read the full article at MedlinePlus

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

Convert E52 to ICD-9-CMHistory

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

ICD-9-CM
265.2 Pellagra
Exact Match The mapping is direct, with no qualifiers.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About E52Overview

Is E52 (Niacin deficiency [pellagra]) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report niacin deficiency [pellagra] on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does E52 group to?

When niacin deficiency [pellagra] is the principal diagnosis on an inpatient stay, it groups to MS-DRG 640, 641, with relative weights from 0.7782 to 1.3356 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of E52?

Under the General Equivalence Mappings, niacin deficiency [pellagra] converts to ICD-9-CM 265.2 (pellagra). The mapping is a direct match.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.