FY2027 ICD-10-CM reference
E00.9: Congenital iodine-deficiency syndrome, unspecified
By the HCC Buddy Coding Team
The official ICD-10-CM descriptor is Congenital iodine-deficiency syndrome, unspecified. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Billable code. Verified against the official FY2027 order file.
FY2027 Tabular instructions
Instructions below include applicable chapter, section and parent-code notes. Each note identifies where it appears in the official source.
Instructional note
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: E00-E89 (chapter, inherited).
Excludes1
transitory endocrine and metabolic disorders specific to newborn (P70-P74)
Source: E00-E89 (chapter, inherited).
Instructional note
code (F70-F79) to identify associated intellectual disabilities.
Source: E00 (category, inherited).
Excludes1
subclinical iodine-deficiency hypothyroidism (E02)
Source: E00 (category, inherited).
Instructional note
Congenital iodine-deficiency hypothyroidism NOS
Source: E00.9 (self, direct).
Instructional note
Endemic cretinism NOS
Source: E00.9 (self, direct).
Compare the FY2027 additions, removals and billable-status changes
What does E00.9 mean in FY2027?
The official ICD-10-CM descriptor is Congenital iodine-deficiency syndrome, unspecified. The FY2027 annual edition starts October 1, 2026. Check the edition that applies to the encounter or inpatient discharge, including any April update.
Is E00.9 billable in FY2027?
The FY2027 order file marks E00.9 as billable. Check the complete Tabular instructions and documentation before assigning it.
Does E00.9 map to an HCC?
E00.9 has no CMS-HCC V28 category in the CMS 2027 Initial ICD-10-CM Mappings (payment year 2027, 2026 dates of service). ESRD, RxHCC, PACE and HHS-HCC mappings are still pending verification for FY2027.
Source: CMS FY2027 ICD-10-CM order file. Read the FY2027 Official Guidelines.
Review the FY2026 April edition