Q90.9 Down syndrome, unspecified

Billable ICD-10-CM code, FY2026. Exempt from present-on-admission (POA) reporting.

Applicable to

• Trisomy 21 NOS

Applies from Q90 Down syndrome

Use additional code

• code(s) to identify any associated degree of intellectual disabilities (F70-F79)

Code also

• associated physical condition(s), such as atrioventricular septal defect (Q21.2-)

MS-DRG index

Defines the logic of DRG(s) 884 in MDC 19.

Approximate ICD-9-CM (GEMs)

• 758.0 Down's syndrome (approximate)

Code annotations containing back-references to Q90.9

Back-references to Q90

• Code First: D84.81 Immunodeficiency due to conditions classified elsewhere ("chromosomal abnormalities (Q90-Q99)")
• Type 1 Excludes: E25 Adrenogenital disorders ("chromosomal abnormalities (Q90-Q99)")
• Type 1 Excludes: Q92 Other trisomies and partial trisomies of the autosomes, not elsewhere classified ("trisomies of chromosomes 13, 18, 21 (Q90-Q91)")
• Type 1 Excludes: Z15 Genetic susceptibility to disease ("chromosomal anomalies (Q90-Q99)")

Diagnosis Index entries for Q90.9

• Down syndrome
• Syndrome › Down
• Syndrome › trisomy › 21
• Trisomy (syndrome) › 21 (partial)

Nearby codes

• Q90 Down syndrome
• Q90.0 Trisomy 21, nonmosaicism (meiotic nondisjunction)
• Q90.1 Trisomy 21, mosaicism (mitotic nondisjunction)
• Q90.2 Trisomy 21, translocation
• Q90.9 Down syndrome, unspecified (this code)