syndromes

Question 1

aneuploidies?

Answer 1

trisomy 13, 18, 21.
Turner (45XO)
klinefelters 47 XXY

Question 2

Trisomy 13

• features
• genetics
• test

Answer 2

• Holoprosencephaly, cleft lip/ palate, heart abnormalities, scalp defect
  
  • Non disjunction event (adv. Maternal age), rarely translocation
  • Test: karyotype, microarray, FISH

Question 3

Trisomy 18

• features
• genetics
• test

Answer 3

• Wizened features (small palprebal fissures and microstomia), prominent occiput, overlapping fingers, rockerbottom feet, multiuple malformations
  
  • Clinical presentation: Prenatally with IUGR/maternal serum screening (low oestriol/PAPPA/beta HCG)
  • Genetics: nondisjunction commonly AMA
    Genetic test: karyotype/miucroarray/FISH

Question 4

Trisomy 21

• features
• genetics
• test

Answer 4

• Hypotonia, facial/physical features, grimace when crying,
  ○ Upslanting palpebral fissues, epicanthal folds, low set ears, small brachycephalic head, small open mouth, tongue hanging out.
  ○ CHD 50% (TOF/AVSD/PDA)
  ○ Other features: hypotonia, short neck with excess skin at back of neck
  ○ GI: atresias 12%, TOF, Hirschprung
  ○ Risks: hypothyroidism, coeliac, leukaemia (AML), atlanto-axial instability, OSA
  
  • Clinical presentation: increased nuchal transmission
• Genetics: nondisjunction commonly AMA
  Genetic test: karyotype/miucroarray/FISH

Question 5

Turner

• features
• genetics
• test

Answer 5

• Short stature, coarcation of aortia, primary ovarian failure, Anteverted ears,
  ○ Dysmorphism: heart shaped face, webbed necl, shield chest, widely spaced nipples, nail hypoplasia, reduced carrying angle
  ○ Other fx: CHD: 20-40% (aortic dilataion 3-5%, bicuspid AV, coartc, hypertension, renal anomalies, 50% (horseshoe kidney), gonadfal dysgenesis (streak ovaries)
  ○ Genetics: 45X) (females only, most spont. Abort)
  ○ Genetic test: FISH/karyotype/FISH
  ○ Natural hx: mild LDs with normal IQ, average adult height 143cm), GH frequently used
  ○ Complications: increased risk of autoimmune dx esp hypothyroidism - annual TFTs and coeliac, risk of aotic dissection

Question 6

klinefelter

• features
• genetics
• test

Answer 6

• Tall build, eunichoid body habitus (slightly female shape
  
  • Reduced musculat/hypogonadism/lack of testosterone. Less musculat, small testes, small penis, gynaecomastia, pubertal delay, underdeveloped secondary sexual characteristics