SP 128: Down Syndrome

• Down syndrome is named after John Langdon Down in 1866, who first systematically described it. After 100 years, people were were able to establish the connection to chromosome 21
• Types of Down Syndrome

  • Trisomy 21
  • Translocation
  • Mosaicism
• Trisomy 21

  • Most common: 95%
  • extra copy of chromosome 21, totaling up to 47 chromosomes instead of 46 due to meiotic non-disjunction
• meiotic non-disjunction is the abnormalities in separating chromosomes in sperm/egg cells
• Mosaicism

  • mixture of 2 types of cells
  • fewer features of DS
  • 1-2% of the cases of DS
• Translocation

  • part of chromosome 21 breaks off during cell division and attaches to other chromosomes, usually 14
  • chromosome is still 46
  • 3-4%
  • only hereditary factor
• Down Syndrome Etiology

  • Cell division error
  • advance maternal age (usually 35 yrs old and up)
  • no behavioral/environmental factors
• DS: Prevalence/Incidence

  • Global: 1 in 10/1000 live births
  • PH: 1 in 800 children
• Physical Symptoms

  • should have a lot of physical symptoms
  • Hypotonia
  • Epicanthal Folds
  • Simian Crease
  • Small oral cavity with large tongue
  • Gap between 1st and 2nd toes
  • Small ears, nose, chin
  • Lack of central fissure in tongue
• Diagnosis

  1. Screening (non-confirmatory)
  2. Prenatal (confirmatory)
  3. Amniocentesis (fluid)
  4. Chronic Villus Sampling (placenta)
  5. miscarriage risk
  6. Postnatal
  7. Physical Symptoms
  8. Blood Karyotyping
• Associated Problems for DS

  • Congenital Heart Disease
  • Intellectual Disorder
  • Vision Problems
  • Hearing
  • Hypothyroidism
  • Obstructive Sleep Apnea
  • Gastrointestinal Problem
  • Blood Disorder
• Congenital Heart Disease

  • 50% incidence
  • common cause for babies with DS up to the first 2 years of their life
  • inability to pump blood efficiently
  • lead to cyanosis
  • echocardiogram by pediatric cardiologist
• Intellectual Disorder

  • Mild to Moderate
  • DS to be the common cause of ID
  • slow earning, poor judgement, short attention span
• Vision Problem

  • Cataract (clouding of eyes): surgery
  • Strabismus (crossed-eye)
  • Nearsightedness: glasses
• Hearing Problem

  • 2/3 of children with DS
  • Sensorineural, Conductive, Otitis media
  • due to narrow auditory canals, cranial nerve difference
• Hypothyroidism

  • decreased production of thyroid hormones
  • results in mental slug, fatigue, weight fluctuation
  • congenital or acquired
  • have thyroid exam at birth, after 6 months, and annually
• Obstructive sleep apnea

  • absence of breathing in sleep
  • to detect CPAP: Continuous Positive Airway Pressure
• Gastrointestinal Problems

  • problem in digesting food due to structural
  • constipation, GERD, Celiac Disease (intolerance to wheat)
• Strengths

  • Social skills
  • engaging, affectionate, pragmatics
  • Receptive skills > expressive skills
• Difficulties

  • delayed expressive vocabulary
  • produce shorter and less complex utterances
  • poor speech intelligibility
  • phonological errors
  • Dysphagia
• Prognosis

  • Average life expectancy
  • 1960s: 10 years old
  • 2007: 46 years old
• • High risk of developing early-onset Alzheimer's disease or dementia in general.
  • by 60 years old, 0-70% of patients with DS develop dementia
• Support Groups

  • Down Syndrome Association of the Philippines (DSAPI)
  • 1991
  • conduct happy walk every year
• Interdisciplinary Team

  • Family
  • Pediatrician, DevPed
  • PT, OT, SP, Teachers
  • Geneticist
  • Audiologist
  • Ophthalmologist
  • Cardiologist
  • Gastroenterologist
  • endocrinologist
  • nutritionist