2021 ICD-10-CM Diagnosis Code Q90.9

Down syndrome, unspecified

    2016 2017 2018 2019 2020 2021 Billable/Specific Code POA Exempt
  • Q90.9 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2021 edition of ICD-10-CM Q90.9 became effective on October 1, 2020.
  • This is the American ICD-10-CM version of Q90.9 - other international versions of ICD-10 Q90.9 may differ.
Applicable To
  • Trisomy 21 NOS
The following code(s) above Q90.9 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to Q90.9:
  • Q00-Q99
    2021 ICD-10-CM Range Q00-Q99

    Congenital malformations, deformations and chromosomal abnormalities

    Note
    • Codes from this chapter are not for use on maternal records
    Type 2 Excludes
    • inborn errors of metabolism (E70-E88)
    Congenital malformations, deformations and chromosomal abnormalities
  • Q90-Q99
    2021 ICD-10-CM Range Q90-Q99

    Chromosomal abnormalities, not elsewhere classified

    Type 2 Excludes
    • mitochondrial metabolic disorders (E88.4-)
    Chromosomal abnormalities, not elsewhere classified
  • Q90
    ICD-10-CM Diagnosis Code Q90

    Down syndrome

      2016 2017 2018 2019 2020 2021 Non-Billable/Non-Specific Code
    Use Additional
    • code(s) to identify any associated physical conditions and degree of intellectual disabilities (F70-F79)
    Down syndrome
Approximate Synonyms
  • Complete trisomy 21 syndrome
  • Downs syndrome
Clinical Information
  • A chromosomal abnormality consisting of the presence of a third copy of chromosome 21 in somatic cells.
  • A chromosomal dysgenesis syndrome resulting from a triplication or translocation of chromosome 21. Down syndrome occurs in approximately 1:700 live births. Abnormalities are variable from individual to individual and may include mental retardation, retarded growth, flat hypoplastic face with short nose, prominent epicanthic skin folds, small low-set ears with prominent antihelix, fissured and thickened tongue, laxness of joint ligaments, pelvic dysplasia, broad hands and feet, stubby fingers, transverse palmar crease, lenticular opacities and heart disease. Patients with down syndrome have an estimated 10 to 30-fold increased risk for leukemia; most have symptoms of alzheimer's disease by age 40. Also known as trisomy 21 syndrome.
  • A chromosome disorder associated either with an extra chromosome 21 or an effective trisomy for chromosome 21. Clinical manifestations include hypotonia, short stature, brachycephaly, upslanting palpebral fissures, epicanthus, brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, simian crease, and moderate to severe intellectual disability. Cardiac and gastrointestinal malformations, a marked increase in the incidence of leukemia, and the early onset of alzheimer disease are also associated with this condition. Pathologic features include the development of neurofibrillary tangles in neurons and the deposition of amyloid beta-protein, similar to the pathology of alzheimer disease. (menkes, textbook of child neurology, 5th ed, p213)
  • A disorder caused by the presence of an extra chromosome 21 and characterized by mental retardation and distinguishing physical features.
  • Chromosome disorder associated either with an extra chromosome 21 or an effective trisomy for chromosome 21; clinical manifestations include hypotonia, short stature, brachycephaly, upslanting palpebral fissures, epicanthus, brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, simian crease, and moderate to severe mental retardation.
  • Down syndrome is set of mental and physical symptoms that result from having an extra copy of chromosome 21. Even though people with down syndrome may have some physical and mental features in common, symptoms of down syndrome can range from mild to severe. Usually, mental development and physical development are slower in people with down syndrome than in those without it.people with the syndrome may also have other health problems. They may be born with heart disease. They may have dementia. They may have hearing problems and problems with the intestines, eyes, thyroid and skeleton.the chance of having a baby with down syndrome increases as a woman gets older. Down syndrome cannot be cured. However, many people with down syndrome live productive lives well into adulthood. nih: national institute of child health and human development
  • The most frequently occurring mental retardation/multiple anomaly syndrome usually involving more than 100 individual defects. Typical facies with upslanting palpebral fissures is the characteristic feature of this syndrome (hence the offensive designations "mongoloid idiocy" and "mongolism"). A wide range other defects, such as congenital heart diseases, respiratory disorders, and leukemia, may be associated. Down syndrome patients who survive into late adulthood may develop alzheimer syndrome.
Present On Admission
POA Help
"Present On Admission" is defined as present at the time the order for inpatient admission occurs — conditions that develop during an outpatient encounter, including emergency department, observation, or outpatient surgery, are considered POA.
  • Q90.9 is considered exempt from POA reporting.
ICD-10-CM Q90.9 is grouped within Diagnostic Related Group(s) (MS-DRG v38.0):
  • 884 Organic disturbances and intellectual disability

Convert Q90.9 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
  • 2021 (effective 10/1/2020): No change

Diagnosis Index entries containing back-references to Q90.9:
  • Down syndrome Q90.9
  • Syndrome - see also Disease
    • trisomy Q92.9
      ICD-10-CM Diagnosis Code Q92.9

      Trisomy and partial trisomy of autosomes, unspecified

        2016 2017 2018 2019 2020 2021 Billable/Specific Code POA Exempt
    • Down Q90.9 - see also Down syndrome
  • Trisomy (syndrome) Q92.9
    ICD-10-CM Diagnosis Code Q92.9

    Trisomy and partial trisomy of autosomes, unspecified

      2016 2017 2018 2019 2020 2021 Billable/Specific Code POA Exempt
    • 21 (partial) Q90.9

ICD-10-CM Codes Adjacent To Q90.9
Q89.2 Congenital malformations of other endocrine glands
Q89.3 Situs inversus
Q89.4 Conjoined twins
Q89.7 Multiple congenital malformations, not elsewhere classified
Q89.8 Other specified congenital malformations
Q89.9 Congenital malformation, unspecified
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
Q91 Trisomy 18 and Trisomy 13
Q91.0 Trisomy 18, nonmosaicism (meiotic nondisjunction)
Q91.1 Trisomy 18, mosaicism (mitotic nondisjunction)
Q91.2 Trisomy 18, translocation
Q91.3 Trisomy 18, unspecified
Q91.4 Trisomy 13, nonmosaicism (meiotic nondisjunction)
Q91.5 Trisomy 13, mosaicism (mitotic nondisjunction)
Q91.6 Trisomy 13, translocation
Q91.7 Trisomy 13, unspecified
Q92 Other trisomies and partial trisomies of the autosomes, not elsewhere classified

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.