Polyglandular dysfunction (E31) ICD-10-CM
The E31 code range covers polyglandular dysfunction with 10 ICD-10-CM diagnosis codes. 8 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Codes in the E31 Range 10 codes · 8 billable
- E31 Polyglandular dysfunctionNon-billable
- E31.0 Autoimmune polyglandular failure
- E31.1 Polyglandular hyperfunction
- E31.2 Multiple endocrine neoplasia [MEN] syndromesNon-billable
- E31.20 Multiple endocrine neoplasia [MEN] syndrome, unspecified
- E31.21 Multiple endocrine neoplasia [MEN] type I
- E31.22 Multiple endocrine neoplasia [MEN] type IIA
- E31.23 Multiple endocrine neoplasia [MEN] type IIB
- E31.8 Other polyglandular dysfunction
- E31.9 Polyglandular dysfunction, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the E31 range.
Multiple Endocrine Neoplasia Type 1
A form of multiple endocrine neoplasia that is characterized by the combined occurrence of tumors in the PARATHYROID GLANDS, the PITUITARY GLAND, and the PANCREATIC ISLETS. The resulting clinical signs include HYPERPARATHYROIDISM; HYPERCALCEMIA; HYPERPROLACTINEMIA; CUSHING DISEASE; GASTRINOMA; and ZOLLINGER-ELLISON SYNDROME. This disease is due to loss-of-function of the MEN1 gene, a tumor suppressor gene (GENES, TUMOR SUPPRESSOR) on CHROMOSOME 11 (Locus: 11q13).
Multiple Endocrine Neoplasia Type 2a
A form of multiple endocrine neoplasia characterized by the presence of medullary carcinoma (CARCINOMA, MEDULLARY) of the THYROID GLAND, and usually with the co-occurrence of PHEOCHROMOCYTOMA, producing CALCITONIN and ADRENALINE, respectively. Less frequently, it can occur with hyperplasia or adenoma of the PARATHYROID GLANDS. This disease is due to gain-of-function mutations of the MEN2 gene on CHROMOSOME 10 (Locus: 10q11.2), also known as the RET proto-oncogene that encodes a RECEPTOR PROTEIN-TYROSINE KINASE. It is an autosomal dominant inherited disease.
Multiple Endocrine Neoplasia Type 2b
Similar to MEN2A, it is also caused by mutations of the MEN2 gene, also known as the RET proto-oncogene. Its clinical symptoms include medullary carcinoma (CARCINOMA, MEDULLARY) of THYROID GLAND and PHEOCHROMOCYTOMA of ADRENAL MEDULLA (50%). Unlike MEN2a, MEN2b does not involve PARATHYROID NEOPLASMS. It can be distinguished from MEN2A by its neural abnormalities such as mucosal NEUROMAS on EYELIDS; LIP; and TONGUE, and ganglioneuromatosis of GASTROINTESTINAL TRACT leading to MEGACOLON. It is an autosomal dominant inherited disease.
About the E31 Code Range
E31 codes cover various types of polyglandular dysfunction, which involve disorders affecting multiple endocrine glands. These ICD-10 codes are used for diagnosing and classifying conditions where several glands either fail, are overactive, or develop tumors simultaneously.
The ICD-10 code E31 includes specific categories like autoimmune polyglandular failure (E31.0), also known as polyglandular autoimmune syndrome type 1 and associated with diseases such as Addison's disease and autoimmune hypoparathyroidism. It also includes polyglandular hyperfunction (E31.1), diagnosing excess hormone activity from multiple glands. The multiple endocrine neoplasia (MEN) syndromes (E31.2-E31.23) codes apply to inherited tumor syndromes affecting multiple endocrine glands, with subtypes MEN type 1, 2A, and 2B recognized, often referred to as polyglandular activity in multiple endocrine adenomatosis. Other less common or unspecified polyglandular dysfunctions are captured under codes E31.8 and E31.9. These codes allow healthcare providers and coders to accurately document complex endocrine disorders involving multiple glands.
Questions About This Page
How many billable codes are in the E31 range?
Of the 10 codes in this range, 8 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the E31 range classify?
The range classifies polyglandular dysfunction. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
