dysmorphology Flashcards
what is morphology and what is mainly looked at?
the scientific study of the structure and form of animals or plants or words and phrases and it mainly looks at features in the face
why is it easier to diagnose in children than babies and adults?
features change with age
what is the epidemiology of congenital malformations?
2-3% of births
what is a likely genetic malformation?
when there are multiple malformations - single are usually isolated events, dysmorphic and family history of similar problems
what is the process of dysmorphology?
gestalt - start at top and work way down paying attention to absence which is just as important as presence of features
what is the significance of dysmorphology?
it assists in making a diagnosis - this is guiding for management, recurrence and prognosis
what does the 22q11.2 deletion result in?
DiGeorge Syndrome - very variable in around 1 in 5000 births
what are the presenting symptoms and their frequency in DiGeorge?
cleft palate in 15%, learning difficulties in around 70%, velopharyngeal insufficiency in around 32%, congenital heart defects in around 75%, hypocalcaemia, seizures, immunodeficiency and renal malformation
what is achondroplasia?
it occurs in around 1 in 20000 and it is an autosomal dominant mutation that is often new. The risk increases with paternal age and results in short stature, foramen magnum compression and hydrocephalus and rhizomelic limb shortening
what is exomphalos?
it is a weakness of the baby’s abdominal wall allowing the abdominal contents to protrude into the abdominal cavity
hemihypertrophy?
when one side of the body or part of one side is larger than the other
what are the characteristics of beckwith-weidemann syndrome?
around 1 in 10000 births with a large tongue, ear pits and creases and exomphalos. There is also hemihypertrophy, neonatal hypoglycaemia and increased risk of wilms tumour - nephroblastoma
what is the commonest chromosomal disorder and what are the characteristics?
down syndrome with 1 in 800 live births. It presents with learning difficulties, impaired hearing, hypotonia in neonates, cataracts, congenital heart disease, single palmar crease, hypothyroidism, leukaemia, atlanto-axial instability and alzheimers risk
what is a single palmar crease indicative of?
down syndrome, other syndromes and chromosomal disorders and in normal population 4% unilateral and 1% bilateral
what is kabuki syndrome?
it is a syndrome that occurs in 1 in 30000 and presents with learning difficulties, premature breast development, hearing impairment, cleft palate, persistent fetal finger pads in 96%, poor growth and congenital heart disease in 50%
