Dysmorphic child Flashcards
Define dysmorphic
abnormal form, usually birth defects and unusual physical features that have origin during embryogenesis
Define syndrome
A particular set of multiple anomalies occurs repeatedly in a consistent pattern and there is known or thought a common underlying causal mechanism
What are the chromosomal causes of dysmorphology
Trisomies: Patau, Edward’s, Down’s
Mutations: Noonan, Fragile X, Pierre-Robin syndrome, achondroplasia
Deletions: Prader-Willi syndrome, Williams syndrome, Cri du chat syndrome (chromosome 5p deletion syndrome, DiGeorge syndrome
Sex-chromosome: Turner’s, Klinefelter’s
Describe Patau syndrome
Trisomy 13
Microcephalic, small eyes
Cleft lip/palate
Polydactyly
Scalp lesions
Kidney defects, spinal defects, infections, intellectual disability, motor disorder
Describe Edward’s syndrome
Trisomy 18
Micrognathia
Low-set ears
Rocker bottom feet
Overlapping of fingers, flexed
Short sternum
Small mouth and chin
Associated with exomphalos/emphalocoele
Describe Down’s syndrome
Trisomy 21
Round face and flat nasal bridge, short neck
Upslanted palpebral fissures
Epicanthic folds (a fold of skin running across the
Inner edge of the palpebral fissure)
Brushfield spots in iris (pigmented spots)
Small mouth and protruding tongue
Small ears
Flat occiput and third fontanelle
Single Palmar creases
Wide Sandal gap between first and second toes
Congenital heart defects
Describe Fragile X syndrome
X-linked recessive disorder
CGG trinucleotide repeat expansion mutation (fragile)
FMR1 gene
Macrocephaly
Long face
Large ears, low-set
Prominent mandible and broad forehead
Macro-orchidism
Learning difficulties, AHD, autism
Joint laxity
Describe Noonan syndrome
Autosomal dominant on Chr 12 with normal karyotype
Mutated RAS/Mitogen Activated Protein Kinase
Webbed neck with trident hair line
Pectus excavatum
Short stature
Pulmonary stenosis and other congenital heart disease
Describe Pierre-Robin syndrome
Micrognathia
Posterior displacement of the tongue (may result in upper airway obstruction)
Cleft palate
Describe achondroplasia
Mutation in FGFR3 gene, autosomal dominant
Short limbs (rhizomelia) with shortened fingers (brachydactyly)
Large face with frontal bossing and narrow foramen magnum
Midface hypoplasia with a flattened nasal bridge
‘Trident’ hands- short stubby fingers with separation between middle and ring fingers
Lumbar lordosis
Describe William’s syndrome
7q11 microdeletion including the elastin gene (Chr7)
Short stature
Learning difficulties
Friendly, extrovert personality
Transient neonatal hypercalcaemia
Supravalvular aortic stenosis
Describe Cri du chat syndrome
Chromosome 5p deletion
Microcephaly and micrognathism
Hypertelorism
Characteristic cry (hence the name) due to larynx and neurological problems
Feeding difficulties and poor weight gain
Learning difficulties
Describe DiGeorge syndrome
22q11.2 microdeletion, autosomal dominant
Associated with the developmental defect of derivatives of the 3rd and 4th pharyngeal pouches- almost always associated with agenesis or hypoplasia of the thymus and PTH gland
Abnormal face (short philtrum, thin upper lip)
Cleft palate
Prominent ears
Micrognathia
High and broad nasal bridge
Occular abnormalities
Narrow downslating palpebral fissures
Long face
Cardiac anomalies - interrupted aortic arch, VSD
Hypoplasia of the thymus gland
Immune dysfunction
Intellectual disability
Autism/ADHD
Developmental delay
Describe Turner’s syndrome
45X (complete or partial absence of X chromosome)
Short stature
Neck webbing or thin neck
Wide carrying angle (cubitus valgus)
Lymphoedema of hands and feet in neonates
Spoon-shaped nails
Pigmented moles
Congenital heart defects (coarctation)
Delayed puberty, infertility (ovarian dysgenesis)
Renal anomalies e.g. horseshoe kidney
Associated with pyloric stenosis
Describe Klinefelter’s syndrome
47 XXY
Gynaecomastia
Tall stature
Otherwise normal appearance and normal IQ
Infertility
Hypogonadism with small testes
