2027 ICD-10-CM Diagnosis Code Z86.17Personal history of Clostridioides difficile infection

ICD-10-CM Codes›Z00–Z99›Z77-Z99›Z86

ICD-10-CM Z86.17
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Z86.17 is a billable ICD-10-CM diagnosis code for personal history of Clostridioides difficile infection. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 951. The code is not accepted as a principal diagnosis by the Medicare Code Editor and exempt from POA reporting.

Code Identity

ICD-10-CM Code
Z86.17
Billable Status
Yes — Valid for Submission
Code Describes
Personal history of Clostridioides difficile infection
Short Description
Personal history of Clostridioides difficile infection
Same as the full description in the CMS dataset.
Parent Code
Z86.1
Personal history of infectious and parasitic diseases

Code Classification

ChapterZ00–Z99Factors influencing health status and contact with health services
SectionZ77-Z99Persons with potential health hazards related to family and personal history and certain conditions influencing health status
CategoryZ86Personal history of certain other diseases
This CodeZ86.17Personal history of Clostridioides difficile infection

Code EditsBilling

Medicare Code Editor checks that affect claim validity for Z86.17.

Unacceptable principal diagnosis
There are selected codes that describe a circumstance which influences an individual's health status but not a current illness or injury, or codes that are not specific manifestations but may be due to an underlying cause. These codes are considered unacceptable as a principal diagnosis.

Present on Admission (POA)Billing

Z86.17 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99).

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Z86.17: its own notes plus those printed at Z86.1, Z86, block Z77-Z99, and Chapter 21. A note printed at a category, block or chapter applies to every code under it.

Applicable To

Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.

  • Personal history of Clostridium difficile colitis (fulminant) (nonfulminant)
  • Personal history of foodborne intoxication by Clostridium difficile
  • Personal history of Pseudomembraneous colitis

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

On Z86.17 itself
  • enterocolitis due to Clostridium difficile, recurrent (A04.71)
From Z86.1 Personal history of infectious and parasitic diseases applies to 8 codes
  • personal history of infectious diseases specific to a body system
  • sequelae of infectious and parasitic diseases (B90-B94)

Code First

The underlying condition named in the note is sequenced before this code.

From Z86 Personal history of certain other diseases applies to 40 codes
  • any follow-up examination after treatment (Z09)

Code Also

A second code may be needed to fully describe the condition; the note gives no sequencing direction.

From Block Z77-Z99 Persons with potential health hazards related to family and personal history and certain conditions influencing health status applies to 567 codes
  • any follow-up examination (Z08-Z09)

Notes

General instructions on how these codes are used.

From Chapter 21 (Z00-Z99) Factors influencing health status and contact with health services applies to 1,425 codes
  • Z codes represent reasons for encounters. A corresponding procedure code must accompany a Z code if a procedure is performed. Categories Z00-Z99 are provided for occasions when circumstances other than a disease, injury or external cause classifiable to categories A00-Y89 are recorded as 'diagnoses' or 'problems'. This can arise in two main ways:
  • (a) When a person who may or may not be sick encounters the health services for some specific purpose, such as to receive limited care or service for a current condition, to donate an organ or tissue, to receive prophylactic vaccination (immunization), or to discuss a problem which is in itself not a disease or injury.
  • (b) When some circumstance or problem is present which influences the person's health status but is not in itself a current illness or injury.

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name Z86.17, its category, or a range that includes it.

Excludes2 1

These codes carry an Excludes2 note naming Z86.17: its condition is not part of those codes, and both may be reported when the patient has both.

  • Z20 Contact with and (suspected) exposure to communicable diseases
    personal history of infectious and parasitic diseases (Z86.1-) names Z86.1-, which includes this code

Use Additional Code 1

These codes say to use an additional code from the note, and Z86.17 is one of the codes named.

  • Z09 Encounter for follow-up examination after completed treatment for conditions other than malignant neoplasm
    code to identify any applicable history of disease code (Z86.-, Z87.-) names Z86.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Code History & ChangesHistory

New Code Z86.17 was added to the ICD-10-CM code set for FY 2027, effective October 1, 2026.

Replacement Z86.17 replaces the following previously assigned code(s):

  • Z86.19 - Personal history of other infectious and parasitic diseases
FY 2027AddedAdded to the ICD-10-CM code setEffective October 1, 2026.
FY 2027CurrentRevised in the current code setEffective October 1, 2026 through September 30, 2027.

Questions About Z86.17Overview

What is the ICD-10 code for personal history of Clostridioides difficile infection?

The ICD-10-CM code for personal history of Clostridioides difficile infection is Z86.17 (sometimes written as Z8617). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is Z86.17 (Personal history of infectious and parasitic diseases) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report personal history of Clostridioides difficile infection on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does Z86.17 group to?

On inpatient claims, personal history of Clostridioides difficile infection maps to MS-DRG 951 (other Factors Influencing Health Status), which carries a relative weight of 0.5574. Higher weights mean higher Medicare reimbursement.

Can Z86.17 be a principal diagnosis?

No. The Medicare Code Editor rejects this code as a principal diagnosis because personal history of Clostridioides difficile infection describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.

Is Z86.17 exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for personal history of Clostridioides difficile infection on inpatient claims. The code appears in the Persons with potential health hazards related to family and personal history and certain conditions influencing health status (Z77-Z99) range of the CMS exempt list.