You’ve got less than a month to prepare for the new diagnosis codes. And while you’re committing them to memory, it’s also important to familiarize yourself with the 2025 ICD-10-CM Guidelines. Just as the codes are updated every October 1st, so are the guidelines, which provide instructions on sequencing, submitting secondary codes and other important diagnosis coding strategies.
Check out a few changes that will hit the ICD-10-CM Guidelines before the calendar turns to October.
Lok to E10.A- for Presymptomatic Diabetes
When it comes to diabetes types, many people only think about type 1 and type 2. But the 2025 ICD-10-CM Guidelines now list instructions for reporting presymptomatic type 1 diabetes mellitus, advising coders on how to submit claims for patients with this condition.
“Codes E10.A-, Type 1 diabetes mellitus, presymptomatic, are assigned for early-stage type 1 diabetes that predates the onset of symptoms,” the 2025 Guidelines say.
For instance, if your provider performs autoantibody testing and detects the presence of diabetes-specific autoantibodies, the doctor may diagnose the patient with presymptomatic type 1 diabetes. In these cases, you’ll submit a claim with E10.A- (Type 1 diabetes mellitus, presymptomatic).
These codes are broken down by stage, as follows:
- E10.A0 (Type 1 diabetes mellitus, presymptomatic, unspecified)
- E10.A1 (Type 1 diabetes mellitus, presymptomatic, Stage 1)
- E10.A2 (Type 1 diabetes mellitus, presymptomatic, Stage 2)
It’s important to review the documentation to look for the presymptomatic diabetes stage. If it’s not available, report E10.A0.
Sepsis Following Postprocedural Infection? Check Two Options
The 2025 ICD-10-CM Guidelines offer new advice for practices that see patients for sepsis diagnoses that occur after a postprocedural wound to the surgical site gets infected.
“For sepsis following a postprocedural wound (surgical site) infection, a code from T81.41 to T81.43, Infection following a procedure, T81.49, Infection following a procedure, other surgical site, or a code from O86.00 to O86.03, Infection of obstetric surgical wound, or code O86.09, Infection of obstetric surgical wound, other surgical site, that identifies the site of the infection should be sequenced first, if known,” the guidelines now state. Text added for 2025 has been bolded.
In addition, you’ll add another code to identify the infectious agent. If the patient has severe sepsis, you should add a code from R65.2 with the additional code(s) for any acute organ dysfunction added as well.
Check Z Codes for Chemo, Immunotherapy Visits
When patients come in specifically for immunotherapy, radiation therapy or chemotherapy, it may be challenging to know which ICD-10-CM code to report, but the guidelines make that clear in 2025.
“If a patient admission/encounter is chiefly for the administration of chemotherapy, immunotherapy or external beam radiation therapy,” assign one of the following as the principal (first-listed) diagnosis code:
- Z51.0 (Encounter for antineoplastic radiation therapy)
- Z51.11 (Encounter for antineoplastic chemotherapy)
- Z51.12 (Encounter for antineoplastic immunotherapy)
The word “chiefly” has been added to make clear that the antineoplastic therapy is the patient’s main reason for the visit.
If the patient has multiple types of antineoplastic therapies on that day, you can assign more than one of these codes. As your secondary diagnosis code, report a code describing the patient’s cancer type.
The 2025 ICD-10-CM codes go into effect on October 1 — less than a month away. Prepare now with insider tips from Maya Turner, CPC, CPMA, CPCO, CPC-I during her online training event, 2025 ICD-10-CM Codes: More Easily Meet Oct. 1st Deadline. Register today!
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