2026 ICD-10-CM Diagnosis Code E31.9Polyglandular dysfunction, unspecified

ICD-10-CM Codes›E00–E89›E20-E35›E31

ICD-10-CM E31.9
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

E31.9 is a billable ICD-10-CM diagnosis code for polyglandular dysfunction, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 643 through 645. Coders also document this condition as polyglandular dysfunction. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified endocrine disorders.

Code Identity

ICD-10-CM Code
E31.9
Billable Status
Yes — Valid for Submission
Code Describes
Polyglandular dysfunction, unspecified
Short Description
Polyglandular dysfunction, unspecified
Same as the full description in the CMS dataset.
Parent Code
E31
Polyglandular dysfunction

Code Classification

ChapterE00–E89Endocrine, nutritional and metabolic diseases
SectionE20-E35Disorders of other endocrine glands
CategoryE31Polyglandular dysfunction
This CodeE31.9Polyglandular dysfunction, unspecified

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Polyglandular dysfunction
  • Polyglandular dysfunction AND/OR related disorders

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.

    • Disturbance(s)
      • polyglandular
    • Dyscrasia
      • polyglandular, pluriglandular
    • Dysfunction
      • polyglandular
    • Endocrinopathy, pluriglandular
    • Polyglandular
      • dyscrasia
    • Polyglandular
      • dysfunction

Clinical ClassificationClinical

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

CCSR END015
Other specified and unspecified endocrine disorders
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Endocrine Diseases

Your endocrine system includes eight major glands throughout your body. These glands make hormones. Hormones are chemical messengers. They travel through your bloodstream to tissues or organs. Hormones work slowly and affect body processes from head to toe. These include:

Read the full article at MedlinePlus

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

Convert E31.9 to ICD-9-CMHistory

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

ICD-9-CM
258.9 Polyglandul dysfunc NOS
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 E31.9Overview

Is E31.9 (Polyglandular dysfunction) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report polyglandular dysfunction, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What MS-DRG does E31.9 group to?

When polyglandular dysfunction, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 643, 644, 645, with relative weights from 0.7683 to 1.6461 depending on complications. Higher weights mean higher Medicare reimbursement.

What is the ICD-9 equivalent of E31.9?

Under the General Equivalence Mappings, polyglandular dysfunction, unspecified converts to ICD-9-CM 258.9 (polyglandul dysfunc NOS). The mapping is a direct match.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.