Q90
Down syndrome
Q90 is a non-billable ICD-10-CM code category for down syndrome. Report a more specific code from it instead. It is part of the FY2027 code set, effective October 1, 2026. The more specific codes under it are Q90.0 Trisomy 21, nonmosaicism (meiotic nondisjunction); Q90.1 Trisomy 21, mosaicism (mitotic nondisjunction); Q90.2 Trisomy 21, translocation and Q90.9 Down syndrome, unspecified. Its coding notes include a Use additional code instruction, a Code also instruction and 2 Excludes2 entries.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
Chapter 17 codes can be used for life. Manifestations that are an inherent part of a specifically coded anomaly are not coded separately. A corrected malformation is reported with a personal history code.
Use additional code
Add the listed code as a secondary code, if known.
- code(s) to identify any associated degree of intellectual disabilities (F70-F79)
Code also
Two codes may be needed to describe the condition. This note gives no sequencing order.
- associated physical condition(s), such as atrioventricular septal defect (Q21.2-)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (2 notes)
- mitochondrial metabolic disorders (E88.4-)
- inborn errors of metabolism (E70-E88)
Notes
Also from chapter/block level (1 note)
- Codes from this chapter are not for use on maternal records