Medical Staff Fact Sheet

Genetics & Etiology

Partial deletion of the short arm of chromosome 5 (5p15.2–15.3)
Deletion size typically 5–40 Mb; larger deletions = more severe presentation
~85% de novo; ~15% inherited from parent with balanced translocation
Prevalence: 1 in 15,000–50,000 live births; ~50–60 cases/year in the US
No racial or ethnic predisposition; slight female predominance
Confirmed by chromosomal microarray (CMA) or FISH

Core Clinical Features

High-pitched cat-like cry in infancy (caused by laryngeal hypoplasia)
Intellectual disability — mild to severe depending on deletion size
Hypotonia — often significant in infancy; improves with age
Microcephaly (postnatal onset)
Distinctive facial features: widely-spaced eyes, low-set ears, micrognathia
Growth retardation — short stature common
Behavioral features: hyperactivity, self-injurious behavior, stereotypies

Associated System Findings

Cardiac

CHD in ~15–20% (VSD most common)
ASD, PDA, tetralogy of Fallot
Echo recommended at diagnosis

Neurological

Hypotonia — universal
Seizures in ~10–15%
MRI: cerebellar hypoplasia, thin CC
EEG if seizure suspected

GI / Feeding

Feeding difficulties common in infancy
GERD frequently reported
G-tube may be present
Constipation (chronic)

Ophthalmologic

Strabismus (~33%)
Myopia
Annual vision screening recommended

Hearing

Recurrent otitis media
Conductive hearing loss
Sensorineural hearing loss (less common)
ABR in infancy recommended

Orthopedic

Scoliosis (progressive)
Hip dysplasia
Flat feet, joint hypermobility
Annual spine assessment

Recommended Screening (Ongoing)

Annual pediatric cardiology if CHD present
Audiology every 1–2 years
Ophthalmology annually
Spine X-ray annually from age 5
Thyroid function (TSH) — every 2–3 years
Dental: increased risk of malocclusion; 6-month intervals
Sleep study if sleep apnea suspected
Neurology referral if seizures or regression noted

Anesthesia & Procedural Notes

Airway may be difficult — laryngeal hypoplasia, micrognathia
Hypotonia increases aspiration risk — NPO guidelines strictly
Cardiac status must be established before GA
May be sensitive to sedation; consider reduced dosing
Higher anxiety with unfamiliar environments — allow caregiver presence as long as possible
Non-verbal patients cannot self-report pain — rely on caregiver and validated pain scales (FLACC, NCCPC)

Communication in the Clinical Setting

AAC Device Sign Language (ASL) Picture Exchange (PECS) Pointing / Eye Gaze Verbal Approximations Yes/No Signals

Ask caregivers: "How does [name] communicate? What are their yes and no signals? Are there words or sounds that mean something specific?" Always address the patient directly — even non-verbal patients understand more than they can express. Keep environment calm; avoid loud sudden noises.

Genetics Referral & Variant Classification

Key Diagnostic Information

Item	Detail
Gene / Locus	5p15.2 (CTNND2, TERT) and 5p15.3 (SEMA5A) — critical regions for specific features
Preferred Test	Chromosomal Microarray (CMA) — detects size and extent of deletion
Parental Testing	Karyotype both parents to rule out balanced translocation (affects recurrence risk)
Recurrence Risk	De novo: <1% recurrence. Parental translocation: up to 50% depending on carrier
Prenatal Diagnosis	Available via CVS or amniocentesis in subsequent pregnancies

Medical Staff Fact Sheet — 5p- Syndrome (Cri du Chat)