trisonomy

Down syndrome

The most common chromosomal anomaly, occurring in about 1 in 700 to 800 births, primarily caused by trisomy of chromosome 21.

Trisomy 21

A chromosomal anomaly resulting in three full copies of chromosome 21, also known as Down syndrome.

Langdon Down

The individual who first described Down syndrome in 1866.

Gene-dosage effect

A hypothesis suggesting that the overexpression of genes on chromosome 21 contributes to the phenotypic abnormalities in Down syndrome.

Down syndrome critical region (DSCR)

The 21q22.1-q22.3 region that appears to contain the gene or genes responsible for congenital heart disease associated with Down syndrome.

Mosaicism

A condition in which some cells have an extra chromosome 21 while others have a normal karyotype, leading to phenotypic variability.

Atlantoaxial hypermobility

Increased range of motion at the first two cervical vertebrae, often associated with Down syndrome.

Epicanthal folds

Skin folds of the upper eyelid that cover the inner corner of the eye, commonly seen in individuals with Down syndrome.

Nuchal translucency (NT) scan

A prenatal screening test that assesses fluid in the fetal neck, used to evaluate the risk of genetic syndromes including Down syndrome.

Amniocentesis

An invasive prenatal diagnostic procedure performed at 14-16 weeks of gestation with a high accuracy in detecting chromosomal disorders.

Chorionic villus sampling (CVS)

A prenatal diagnostic test performed at 10-13 weeks of gestation to detect chromosomal anomalies.

Hypothyroidism

A condition of thyroid hormone deficiency commonly associated with Down syndrome.

Self-care deficit

A nursing diagnosis related to the impaired ability to perform activities of daily living in individuals with Down syndrome.

Delayed growth and development

A nursing diagnosis indicating the slower than expected development of physical and cognitive skills in children with Down syndrome.

Protruding tongue

A characteristic craniofacial finding in Down syndrome where the tongue appears thick and sticks out of the mouth.

Brushfield spots

Speckling of the iris often observed in individuals with Down syndrome.

Congenital heart disease

Heart defects that present at birth, commonly seen in individuals with Down syndrome.

Celiac disease

A GI manifestation that can occur in about 5% of patients with Down syndrome.

Digitalis

A medication used for cardiac management in individuals with Down syndrome.

Buccal smear

A diagnostic test performed on sexually active women with Down syndrome to screen for cervical cancer.

Hypersensitivity to pilocarpine

An exaggerated response to the drug, observed in patients with Down syndrome due to decreased buffering of physiologic reactions.

Papanicolaou (Pap) smear

A screening test for cervical cancer recommended for women with Down syndrome starting at the age of first intercourse.

Fluorescence in situ hybridization (FISH)

A rapid diagnostic method used to detect trisomy 21 in prenatal and neonatal testing.

Mild to moderate intellectual disability

The common cognitive impairment associated with Down syndrome.

Increased insulin resistance

A metabolic change seen in patients with Down syndrome leading to a predisposition to obesity.

Transient myeloproliferative disorder

A type of leukemia that children with Down syndrome are predisposed to develop.

Physical assessment

A systematic approach to evaluate the physical health of a child with Down syndrome.

Developmental milestones

Key activities and skills that children typically achieve, which may be delayed in those with Down syndrome.

Flu vaccination

Immunization recommended for children with Down syndrome who have chronic cardiac and respiratory diseases.

Thyroid hormone replacement

Medications given to patients with Down syndrome to manage hypothyroidism.

Parental education

Providing information and support to parents of children with Down syndrome to help them understand and care for their child.

Autism spectrum disorder

A condition that may co-occur with Down syndrome, requiring careful assessment and support.

Genetic counseling

A process to help families understand the genetic aspects and risks related to Down syndrome.

Social skills development

An important area of focus for children with Down syndrome to encourage appropriate interactions and communication.

Cervical spine stabilization

Surgical intervention may be needed in Down syndrome to prevent or address atlantoaxial subluxation.

Failure to thrive

A potential issue in infants with Down syndrome, often related to feeding difficulties.