CurrentUnitedHealthcarePolicy N/A

Inappropriate primary ICD-10 diagnosis codes for claims

Defines which ICD-10-CM diagnosis codes are inappropriate to report as the principal/primary diagnosis on UB-04 and CMS-1500 claims for UnitedHealthcare Community Plan Medicaid and describes state-specific exceptions.

Policy Summary

PayerUnitedHealthcare

PolicyInappropriate primary ICD-10 diagnosis codes for claims

Policy CodePolicy N/A

Change TypeState exceptions added/updated

Effective DateN/A

Next Review DateN/A

Key ActionSubmit accurate claims with appropriate diagnosis codes on UB-04 or CMS-1500 (or electronic equivalents) following ICD-10-CM Official Guidelines.

SourceLink

POLICY UPDATE CHANGES

Maryland and Washington D.C. were added to the State Exceptions list.

Multiple state exceptions were updated (Arizona, Idaho, Indiana, Kansas, Kentucky, Missouri, Nebraska, New Jersey, New York, Ohio, Texas).

Hawaii and New Mexico were added to the State Exceptions list.

UB-04 & CMS-1500Claim form types governed

MultipleState-specific deviations

AttachmentsSupplemental list

>10Policy updates

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Inappropriate Primary Diagnosis — Scope and Criteria

Coverage criteria for primary diagnosis coding

Inappropriate Primary ICD-10 Diagnosis Codes List applies to professional and outpatient facility claims; refer to attachments and state-specific exceptions for allowed deviations.

The correct primary/principal ICD-10-CM diagnosis must be submitted in the appropriate claim field (Box 67 on UB-04 or Box 24E on CMS-1500) to be eligible for reimbursement.

Codes included in the Inappropriate Primary ICD-10 Diagnosis Codes List are not allowed as the principal/primary diagnosis on professional and outpatient facility claims unless a documented state-specific exception applies.

When the Inappropriate Primary ICD-10 Diagnosis Codes List is used, follow the ICD-10-CM Official Guidelines for Coding and Reporting for sequencing, manifestation coding, code-first notes, and Excludes1 rules.

ALL of the following

If an inappropriate principal diagnosis is submitted in Box 67 of the UB-04, the entire claim will be denied.
If an inappropriate diagnosis is linked as primary on a CMS-1500 with multiple service lines, only the claim line(s) associated with that primary diagnosis will be denied.

Refer to the policy attachments for the full Inappropriate Primary ICD-10 Diagnosis Codes List and to state-specific attachments for deviations (for example, Rhode Island and Kansas maintain state-specific lists).

Sequencing, Examples, and Special Coding Rules

Examples and special sequencing rulesICD-10

T86	Complications of transplanted organs and tissue (use before coding malignant neoplasm of transplanted organ)
C80.2	Malignant neoplasm without specification of site (used with transplant complication coding)
T51-T65	Toxic effects of substances (assign these before condition codes caused by external agents)
R65	Sepsis, severe sepsis, and septic shock category referenced

Sequela coding (sequencing guidance)

Standard sequencingGenerally requires two codes: the condition or nature of the sequela first, and the sequela code second.

ExceptionsExceptions when the sequela code is followed by a manifestation code, or when the sequela code has been expanded to include the manifestation(s).

Transplant guidanceCode malignant neoplasm of a transplanted organ as a transplant complication: assign T86 (complications of transplanted organs and tissue) first, then C80.2.

External agent causesFor conditions caused by external/toxic agents, assign the agent code (T51-T65) first, then the condition code; in pregnancy, assign the toxic effect code first, then the pregnancy code.

Key Definitions

Manifestation code — definition and sequencing

DefinitionA manifestation code describes the manifestation of an underlying disease and should not be reported as the first-listed or principal diagnosis when it is a manifestation of another condition.

Sequencing ruleWhen a manifestation code is present, the underlying cause should be sequenced first (consult 'code first' notes where applicable).

Official guidanceRefer to the ICD-10-CM Official Guidelines for Coding and Reporting for detailed descriptions and sequencing rules for manifestation codes.

Excludes1 — mutually exclusive codes

Excludes1 definitionAn Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note (mutually exclusive diagnoses).

Impact on primary diagnosis

Billing, Submission, and Denial Guidance for Providers

Prior Authorization

Submit accurate claims with correct diagnosis coding

You are responsible for submitting accurate claims with the correct primary/principal ICD-10-CM diagnosis on the appropriate claim form field (Box 67 on UB-04 or Box 24E on CMS-1500) or their electronic equivalents; follow the ICD-10-CM Official Guidelines for Coding and Reporting when assigning and sequencing diagnosis codes to ensure reimbursement eligibility.

Applies to claims submitted on UB-04, CMS-1500, or electronic equivalents.
Follow ICD-10-CM Official Guidelines for Coding and Reporting for sequencing, manifestation, and Excludes1 guidance.

Denial Risk

Denial behavior differs by claim form

If an inappropriate diagnosis is reported as the primary diagnosis on a CMS-1500 (Box 24E) and multiple claim lines exist, only the line(s) associated with that diagnosis will be denied; however, if an inappropriate principal diagnosis is submitted in Box 67 of the UB-04, the entire claim will be denied.