Version 2024

2024 ICD-10-CM Diagnosis Code Q90

Down syndrome

ICD-10-CM Code:
Q90
ICD-10 Code for:
Down syndrome
Is Billable?
Not Valid for Submission
Code Navigator:

Code Classification

  • Congenital malformations, deformations and chromosomal abnormalities
    (Q00-Q99)
    • Chromosomal abnormalities, not elsewhere classified
      (Q90-Q99)
      • Down syndrome
        (Q90)

Q90 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of down syndrome. The code is not specific and is NOT valid for the year 2024 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Specific Coding Applicable to Down syndrome

Non-specific codes like Q90 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for down syndrome:

  • Use Q90.0 for Trisomy 21, nonmosaicism (meiotic nondisjunction) - BILLABLE CODE

  • Use Q90.1 for Trisomy 21, mosaicism (mitotic nondisjunction) - BILLABLE CODE

  • Use Q90.2 for Trisomy 21, translocation - BILLABLE CODE

  • Use Q90.9 for Down syndrome, unspecified - BILLABLE CODE

Clinical Information

  • Down 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, single transverse palmar 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)

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Code Also

Code Also
A "code also" note instructs that two codes may be required to fully describe a condition, but this note does not provide sequencing direction.
  • associated physical conditions, such as atrioventricular septal defect Q21.2

Use Additional Code

Use Additional Code
The “use additional code” indicates that a secondary code could be used to further specify the patient’s condition. This note is not mandatory and is only used if enough information is available to assign an additional code.
  • codes to identify any associated degree of intellectual disabilities F70 F79

Patient Education


Down Syndrome

What is Down syndrome?

Down syndrome is a condition in which a person has an extra chromosome or an extra piece of a chromosome. This extra copy changes how a baby's body and brain develop. It can cause both mental and physical challenges during their lifetime. Even though people with Down syndrome might act and look similar, each person has different abilities.

What causes Down syndrome?

Chromosomes are tiny "packages" in your cells that contain your genes. Genes carry information, called DNA, that controls what you look like and how your body works. People with Down syndrome have an extra copy of chromosome 21. In some cases, they may have an extra copy of part of the chromosome. Having an extra copy of a chromosome is called trisomy. So sometimes Down syndrome is also called trisomy 21.

Down syndrome is usually not inherited. It happens by chance, as an error when cells are dividing during early development of the fetus. It is not known for sure why Down syndrome occurs or how many different factors play a role.

One factor that increases the risk of having a baby with Down syndrome is the age of the mother. Women ages 35 and older are more likely to have a baby with Down syndrome.

What are the symptoms of Down syndrome?

The symptoms of Down syndrome are different in each person. And people with Down syndrome may have different problems at different times of their lives. They usually have mild to moderate intellectual disabilities. Their development is often delayed. For example, they may start talking later than other children.

Some of the common physical signs of Down syndrome include:

  • A flat face
  • Eyes that slant up
  • A short neck
  • Small hands and feet
  • Poor muscle tone
  • Loose joints

What other problems does Down syndrome cause?

Many people with Down syndrome have the common physical signs and have healthy lives. But some people with Down syndrome might have one or more birth defects or other health problems. Some of the more common ones include:

  • Hearing loss
  • Sleep apnea (a disorder that causes you to repeatedly stop breathing during sleep)
  • Ear infections
  • Eye diseases
  • Congenital heart defects (heart defects that are present at birth)
  • Digestive problems
  • Problems with the upper part of the spine
  • Obesity
  • How is Down syndrome diagnosed?

    Health care providers can check for Down syndrome during pregnancy or after a child is born.

    There are two basic types of tests that help find Down syndrome during pregnancy:

    • Prenatal screening tests can show whether your unborn baby has a higher or lower chance of having Down syndrome. If a screening test shows that your baby could have Down syndrome, you'll need another test to find out for sure.
    • Prenatal diagnostic tests can diagnose or rule out Down syndrome by checking the chromosomes in a sample of cells.

    These tests have a small risk of causing a miscarriage, so they're often done after a screening test shows that an unborn baby could have Down syndrome.

    After a baby is born, the provider may make an initial diagnosis of Down syndrome based on the physical signs of the syndrome. The provider can use a karyotype genetic test to confirm the diagnosis. The test can check for extra chromosomes in a sample of the baby's blood.

    What are the treatments for Down syndrome?

    There is no single, standard treatment for Down syndrome. Treatments are based on each person's physical and intellectual needs, strengths, and limitations.

    Services early in life focus on helping children with Down syndrome develop to their full potential. These services include speech, occupational, and physical therapies. They are typically offered through early intervention programs in each state. Children with Down syndrome may also need extra help or attention in school, although many children are included in regular classes.

    Since people with Down syndrome can have birth defects and other health problems, they will need regular medical care. They may need to have certain extra health screenings to check for problems that happen more often in people with Down syndrome.

    Centers for Disease Control and Prevention


    [Learn More in MedlinePlus]

    Down syndrome

    Down syndrome is a chromosomal condition that is associated with intellectual disability, a characteristic facial appearance, and weak muscle tone (hypotonia) in infancy. All affected individuals experience cognitive delays, but the intellectual disability is usually mild to moderate.

    People with Down syndrome often have a characteristic facial appearance that includes a flattened appearance to the face, outside corners of the eyes that point upward (upslanting palpebral fissures), small ears, a short neck, and a tongue that tends to stick out of the mouth. Affected individuals may have a variety of birth defects. Many people with Down syndrome have small hands and feet and a single crease across the palms of the hands. About half of all affected children are born with a heart defect. Digestive abnormalities, such as a blockage of the intestine, are less common.

    Individuals with Down syndrome have an increased risk of developing several medical conditions. These include gastroesophageal reflux, which is a backflow of acidic stomach contents into the esophagus, and celiac disease, which is an intolerance of a wheat protein called gluten. About 15 percent of people with Down syndrome have an underactive thyroid gland (hypothyroidism). The thyroid gland is a butterfly-shaped organ in the lower neck that produces hormones. Individuals with Down syndrome also have an increased risk of hearing and vision problems. Additionally, a small percentage of children with Down syndrome develop cancer of blood-forming cells (leukemia).

    Delayed development and behavioral problems are often reported in children with Down syndrome. Affected individuals can have growth problems and their speech and language develop later and more slowly than in children without Down syndrome. Additionally, speech may be difficult to understand in individuals with Down syndrome. Behavioral issues can include attention problems, obsessive/compulsive behavior, and stubbornness or tantrums. A small percentage of people with Down syndrome are also diagnosed with developmental conditions called autism spectrum disorders, which affect communication and social interaction.

    People with Down syndrome often experience a gradual decline in thinking ability (cognition) as they age, usually starting around age 50. Down syndrome is also associated with an increased risk of developing Alzheimer's disease, a brain disorder that results in a gradual loss of memory, judgment, and ability to function. Approximately half of adults with Down syndrome develop Alzheimer's disease. Although Alzheimer's disease is usually a disorder that occurs in older adults, people with Down syndrome commonly develop this condition earlier, in their fifties or sixties.


    [Learn More in MedlinePlus]

    Code History

    • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
    • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
    • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
    • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
    • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
    • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
    • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
    • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
    • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.