Are You Ready for the New Diagnosis Codes?

The ICD-10-CM codes and guidelines for the 2025 fiscal year (FY) have been released. The new codes will become effective on Oct. 1, 2024.

The ICD-10-CM guidelines have minor updates, and include the following:

• Chapter 2.s – Breast Implant Associated Anaplastic Large Cell Lymphoma had a revision reading “C84.7B, anaplastic large cell lymphoma, ALK-negative, in remission, for BIA-ALCL in remission.”
• Chapter 2.t – Secondary malignant neoplasm of lymphoid tissue has been updated to note that categories of C81-C85 with a final character identifying “extranodal and solid organ sites” should be assigned, rather than a code for the secondary neoplasm of the affected solid organ.
• Chapter 4.a.1.a – a guideline for pre-symptomatic Type 1 diabetes mellitus has been added.
• Chapter 18.i has been updated to include the code range for acute strokes (I60-I63).
• Chapter 21.c has an update to the categories of Z codes, to include the status of Z17 description, which was expanded to include “and other hormones and factors.”

The FY 2025 diagnosis code release resulted in a total of 74,260 codes. There are 252 additions, 36 deletions, and 13 revisions. The new codes include the following:

• Multiple lymphoma, in remission codes;
• Presymptomatic Type 1 diabetes mellitus;
• Hypoglycemic levels;
• Carcinoid syndrome;
• Obesity classes;
• Expansion of anorexia nervosa, bulimia nervosa, and binge eating;
• KCNQ2 epilepsy;
• Degenerative myopia;
• Internal and external nasal collapse;
• Expansion of anal and rectal fistula;
• Expansion of intervertebral disc degeneration (to include associated symptoms); and
• Expansion of synovitis and tenosynovitis, to include anatomic site.

The Table of Drugs and Chemicals has been updated to include immune checkpoint inhibitors. This chapter also includes dehiscence of gastrointestinal tract, internal operation wound, and deep operation wound.

The Z codes include progesterone receptor status as well as expanded personal history of colonic polyps, which includes type. This chapter includes receptor status of other hormones and sepsis aftercare. The Social Determinants of Health (SDoH) section has been expanded to include insufficient social insurance and welfare support.

I am excited to see the expansion of the obesity codes, to include the obesity classes, which are frequently documented in medical records. The expansion of diabetes to include pre-diabetes Type 1 is interesting. This update also confirms that the SDoH are here to stay, and this data will continue to be important to capture. The biggest guideline change is the addition of guidelines for pre-symptomatic, Type 1 diabetes mellitus.

This code and guideline update will be further discussed during the ICD10monitor  August webinars.

Resources:

https://www.cms.gov/medicare/coding-billing/icd-10-codes/2025-icd-10-cm