E06.5 Other chronic thyroiditis

The ICD-10-CM code for Other chronic thyroiditis is E06.5 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Chapter

4: Endocrine, nutritional and metabolic diseases (E00-E89)

Section

E00-E07: Disorders of thyroid gland (E00-E07)

Category E06

8 codes (7 billable)

FY2026 Status

Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to E06.5:

• Ligneous thyroiditis
• Struma › Riedel's
• Thyroiditis › woody
• Thyroiditis › chronic (nonspecific) (sclerosing)
• Riedel's › struma, thyroiditis or disease
• Thyroiditis › fibrous (chronic)
• Thyroiditis › ligneous
• Thyroiditis › Riedel's

Inclusion Terms

• Chronic fibrous thyroiditis
• Chronic thyroiditis NOS
• Ligneous thyroiditis
• Riedel thyroiditis

U.S. Hospital Utilization

• An estimated 310 U.S. inpatient stays in 2023 included E06.5 among the documented diagnoses.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

Diabetes mellitus (TOC entry)

a. Diabetes mellitus ................................................................................................................... 39

Obesity (TOC entry)

b. Obesity .................................................................................................................................. 42

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

• CMS — ICD-10-CM Official Code Set and Guidelines, FY2026
• CDC/NCHS — ICD-10-CM Files and Browser Tool
• AHRQ — HCUP National Inpatient Sample, Frequencies by Diagnosis Code (2016–2023)