ICD-10-CM Q99: Other chromosome abnormalities, not elsewhere classified

ICD-10-CM Diagnosis Code (2025)

Official Description for Q99

Other chromosome abnormalities, not elsewhere classified

Coding Notes & Guidelines for Q99

Inclusion Terms

Chimera 46, XX/46, XY true hermaphrodite

Inclusion Terms
  • 46, XX with streak gonads
  • 46, XY with streak gonads
  • Pure gonadal dysgenesis
Inclusion Terms

Fragile X syndrome

Child Codes (More Specific Codes for Q99):

Q99.0 - Chimera 46, XX/46, XY Q99.1 - 46, XX true hermaphrodite Q99.2 - Fragile X chromosome Q99.8 - Other specified chromosome abnormalities Q99.9 - Chromosomal abnormality, unspecified

About ICD-10-CM Code Q99 (Other chromosome abnormalities)

ICD-10-CM code Q99 is a billable or specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. The 2025 edition of ICD-10-CM Q99 became effective on October 1, 2024.

This page provides detailed information about Q99 - Other chromosome abnormalities, not elsewhere classified. It includes common terminology, coding guidelines such as "Includes," "Excludes1," and "Excludes2" notes, and information on required 7th characters. Utilizing this information correctly is essential for accurate medical coding and claims submission for conditions like Other chromosome abnormalities related to not elsewhere classified.