18p- Treatment and Surveillance

ICD-10 = Q99.9 or Q93.89

These recommendations are inclusive of the entire population of people with 18p deletions. Even though about half of this group have deletions of the entire short arm of the chromosome and the other half have individually unique deletion of only a portion of the chromosome arm. Consequently, not everyone with 18p- has exactly the same genes that are hemizygous. The specific hemizygous genes for an individual patient will dictate the probability of particular phenotypes. However, the information in this document includes the global 18p- evaluation and management plan.

18p- An interstitial or terminal deletion of any region of chromosome 18p between the end of the chromosome (at 1bp) and the centromere (at 15.6 Mb). 18p has 66 genes, only a few of which are thought to either lead to haploinsufficiency or are conditionally dosage sensitive. For more information on the genes see: https://wp.uthscsa.edu/chrome-18/research
  • Structural
    • Hernias (inguinal, umbilical)
    • Heart abnormalities
    • Cryptorchidism
    • Sacral agenesis / myelomeningocele
  • Functional
    • Respiratory
    • Feeding problems
    • Hypotonia
  • Biochemical
    • Jaundice
    • Hypoglycemia

Initial evaluations after diagnosis

  • Cerebral MRI-abnormalities – >70%
  • Ophthalmology exam-
    • ptosis-47%
    • vision and optic problems – >38%
  • Audiology evaluation – hearing deficits-22%
  • Thyroid evaluation-thyroid problems-17%
  • Cardiology exam-cardiac defects-45%
  • Orthopedic exam-orthopedic problems 47%
  • Renal ultrasound-hydronephrosis
    or malformations-14%

Referrals to

  • Appropriate sub-specialist as indicated by initial evaluations
  • Genetics Follow -up if not previous to diagnosis
  • 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
  • Ear infections
  • Immunology/Rheumatology
    • Atopic disorders
    • Arthritis
    • Other autoimmune conditions
  • Orthopedics
    • Scoliosis or kyphosis
    • Sacral agenesis
  • Development
    • Milestones
    • Psychmetric data
    • Current Adult Status
  • Neurology
    • Seizure disorder
    • Balance problems
    • Muscle weakness
    • Hypotonia

Annual Screenings

  • Thyroid
  • Vision
  • Hearing

Current Adult Status

Age and Cause of Death

Updated 2020