Proximal 18q- Treatment and Surveillance

ICD-10 = Q99.9 or Q93.89

These recommendations are inclusive of the entire population of people with  Proximal 18q deletions even though each person has a unique deletion. Therefore each person’s deletion could have different genes that are hemizygous. The specific hemizygous genes for an individual patient will dictate the probability of particular phenotypes. Guidance for creating an individualized plan for evaluation and management based on the person’s specific deletion can be found in the next section. However, the information in this document  encompasses the global proximal 18q- evaluation and management plan.

ideogram of chromosome 18 with text describing proximal 18q-. (18q11.2-q21.1) An interstitial deletion within the region between 20,000,000 and 45, 700,000 basepairs;* a region that includes 80 genes. *hg 19 nucleotide scale.
Potential conditions in a neonate
  • Structural
    • Palate abnormality
  • Functional
    • Respiratory
    • Feeding difficulties
    • Central apnea
    • Hypotonia
  • Biochemical
    • Jaundice

Initial evaluations after diagnosis

  • Cardiology evaluation – 50% have cardiac defects
  • Hearing evaluation – 30% with hearing deficits
  • Renal ultrasound – 43% with reflux
  • Vision evaluation – 64% with optic problems
  • MRI- 62% abnormal findings

Referrals to

Appropriate sub-specialist as indicated by initial evaluations

  • Genetics Follow-up
    • Parents genotyped for balanced rearrangements
  • Early intervention/developmental services
  • The Chromosome 18 Registry & Research Society
  • The Chromosome 18 Clinical Research Center

Closely monitor and manage

  • Failure to thrive/ growth failure
    • Weight gain
    • Linear growth
  • Sinus/ ear infections
  • Genitourinary
    • Reflux
  • Gastrointestinal
  • Immunology/Rheumatology
    • Atopic disorders
  • Orthopedics
    • Scoliosis
  • Respiratory issues
  • Neurology
    • Seizure disorder
    • Tremors
    • hypotonia
  • Development
    • Milestones
    • Psychometric data

Annual Screenings

  • Vision
  • Hearing

Current Adult Status

Age and Cause of Death