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v1.0.0
ICD-10 Guide
ICD-10 CodesQ91.3

Q91.3

Billable

Trisomy 18, unspecified

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/11/2025

Code Description

ICD-10 Q91.3 is a billable code used to indicate a diagnosis of trisomy 18, unspecified.

Key Diagnostic Point:

Trisomy 18, also known as Edwards syndrome, is a chromosomal abnormality characterized by the presence of an extra 18th chromosome. This condition leads to severe developmental delays and a range of congenital malformations. Infants with Trisomy 18 often present with low birth weight, a small head (microcephaly), a prominent back of the head, and a clenched fist with overlapping fingers. Other common features include heart defects, kidney abnormalities, and gastrointestinal issues. The prognosis for infants with Trisomy 18 is generally poor, with many not surviving past their first year of life. Diagnosis is typically made through prenatal screening and confirmed via genetic testing. The condition is associated with advanced maternal age and is not inherited in most cases. Management focuses on supportive care and addressing specific medical issues as they arise.

Code Complexity Analysis

Complexity Rating: High

High Complexity

Complexity Factors

  • Variability in clinical presentation and severity of symptoms
  • Need for precise documentation of associated congenital anomalies
  • Differentiation from other chromosomal abnormalities
  • Potential for co-morbid conditions requiring additional coding

Audit Risk Factors

  • Inadequate documentation of clinical findings
  • Failure to capture associated congenital anomalies
  • Misclassification of the condition due to similarity with other trisomies
  • Lack of genetic testing documentation

Specialty Focus

Medical Specialties

Pediatrics

Documentation Requirements

Detailed clinical notes on growth, development, and any interventions provided.

Common Clinical Scenarios

Management of feeding difficulties, cardiac issues, and developmental assessments.

Billing Considerations

Ensure all congenital anomalies are documented to support coding and billing.

Genetics

Documentation Requirements

Genetic testing results, family history, and counseling notes.

Common Clinical Scenarios

Prenatal counseling, postnatal genetic testing, and family planning discussions.

Billing Considerations

Accurate coding requires thorough documentation of genetic findings and implications.

Coding Guidelines

Inclusion Criteria

Use Q91.3 When
  • Follow ICD
  • CM guidelines for coding congenital conditions, ensuring specificity in documentation and adherence to coding conventions for chromosomal abnormalities

Exclusion Criteria

Do NOT use Q91.3 When
No specific exclusions found.

Related ICD-10 Codes

Related CPT Codes

81228CPT Code

Chromosomal analysis, karyotype

Clinical Scenario

Used for confirming diagnosis of Trisomy 18 through genetic testing.

Documentation Requirements

Document the reason for testing and results.

Specialty Considerations

Genetic specialists should ensure comprehensive documentation of findings.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of congenital conditions, improving the accuracy of data collection and reimbursement processes.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of congenital conditions, improving the accuracy of data collection and reimbursement processes.

Reimbursement & Billing Impact

reimbursement processes.

Resources

Clinical References

  • •
    CDC - Trisomy 18 Information

Coding & Billing References

  • •
    CDC - Trisomy 18 Information

Frequently Asked Questions

What are the common features of Trisomy 18?

Common features include low birth weight, microcephaly, clenched fists, and multiple congenital anomalies affecting the heart, kidneys, and gastrointestinal tract.