ICD-10-CM 2027 diagnosis code
Z86.17Personal history of Clostridioides difficile infection
Z86.17 is a valid, billable ICD-10-CM code for personal history of clostridioides difficile infection. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS, effective October 1, 2026. Updated September 29, 2026. About our data
About Z86.17
Z86.17 is the ICD-10-CM diagnosis code for personal history of Clostridioides difficile infection. It belongs to category Z86 (personal history of certain other diseases), block Z77-Z99 (persons with potential health hazards related to family and personal history and certain conditions influencing health status) and chapter 21 (factors influencing health status and contact with health services). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within Z86.1 (personal history of infectious and parasitic diseases), Z86.17 is specifically for personal history of Clostridioides difficile infection. Related codes cover tuberculosis (Z86.11), poliomyelitis (Z86.12), malaria (Z86.13), Methicillin resistant Staphylococcus aureus infection (Z86.14), latent tuberculosis infection (Z86.15), COVID-19 (Z86.16) and other infectious and parasitic diseases (Z86.19).
Don't report Z86.17 together with the conditions in its Excludes1 note: enterocolitis due to Clostridium difficile, recurrent (A04.71).
Code first: any follow-up examination after treatment (Z09).
It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.
In MS-DRG v44.0, it is part of the grouping logic for DRG 951 (Other Factors Influencing Health Status, relative weight 0.5577), in MDC 23 (Factors Influencing Health Status and Other Contacts with Health Services), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
It is exempt from present-on-admission (POA) reporting, so no POA indicator is required.
It was added in FY2027, effective October 1, 2026.
Coding notes
- Personal history of Clostridium difficile colitis (fulminant) (nonfulminant)
- Personal history of foodborne intoxication by Clostridium difficile
- Personal history of Pseudomembraneous colitis
- enterocolitis due to Clostridium difficile, recurrent (A04.71)
Notes that apply from higher levels
Instructions written at a parent level also apply to Z86.17.
› From Z86 Personal history of certain other diseases
- any follow-up examination after treatment (Z09)
Broader instructions also apply from Z77-Z99 Persons with potential health hazards related to family and personal history and certain conditions influencing health status and Chapter 21: Factors influencing health status and contact with health services.
Alphabetic index entries
5 entriesTerms in the official ICD-10-CM index that lead to Z86.17.
- History › personal (of) › Clostridium difficile › colitis (fulminant) (nonfulminant)
- History › personal (of) › Clostridium difficile › difficile infection
- History › personal (of) › Clostridium difficile › foodborne intoxication
- History › personal (of) › infection NEC › Clostridioides (Clostridium) difficile (colitis) (infection)
- History › personal (of) › malignant neoplasm (of) › Pseudomembraneous colitis
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 23 · Factors Influencing Health Status and Other Contacts with Health Services
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2027 (effective 10/1/2026): Added
Common questions about Z86.17
Is Z86.17 billable?
- Yes. Z86.17 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can Z86.17 be used as a principal diagnosis?
- No. It is not acceptable as the principal diagnosis for an inpatient stay; it may be reported as a secondary diagnosis.
Is Z86.17 a CC or MCC?
- No. Z86.17 is neither a CC nor an MCC under MS-DRG v44.0.
What DRG does Z86.17 group to?
- Z86.17 is used in the MS-DRG v44.0 logic for MS-DRG 951 (Other Factors Influencing Health Status). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
Did Z86.17 change for 2027?
- Yes. For FY2027 (effective October 1, 2026) it was added to the code set.