cleft palate, microcephaly, and midface hypoplasia

[khushboo]

A 16-year-old boy is seen for the first time by a physician, who notes the patient was born with a cleft palate, microcephaly, and midface hypoplasia. A heart murmur was detected at 2 months of age. The patient had been treated many times for recurrent otitis media but had not had regular medical care. The physician noted a long face that appeared hypotonic with narrow palpebral fissures, puffy eyelids, a squared nasal root, and a narrow alar base with thin alae nasi. The mother demonstrated a similar but less severe constellation of features. Because a diagnosis was missing from the patient's chart, the physician ordered fluorescent in situ hybridization (FISH) analysis for both the mother and the patient. An abnormality is most likely to be found in what chromosome location?

A. 4p
B. 7q11
C. 15q11-12
D. 17p11.2
E. 22q11.2

[ashishkabir]

E - 22q11.2 this is
diGeorge syndrome / Velocardiofacial syndrome

[ashishkabir]

Can someone help with the others - many of them I had to look up but here is what I think...

a is Wolf-Hirschhorn Syndrome - which I'd never heard of before -
http://emedicine.medscape.com/article/950480-overview

b is Either - (confused about this one - I know we're supposed to know Williams)
Shwachman-Diamond Syndrome - the name sounded familiar but I'm not sure if we're supposed to know about it -
http://emedicine.medscape.com/article/958476-overview

OR

Williams Syndrome:
http://en.wikipedia.org/wiki/Williams_syndrome


c is Angelman or Prader willi - this one we associate with imprinting.


d is Hereditary Neuropathy with Liability to Pressure Palsy - which I'd never heard of before either:
http://ghr.nlm.nih.gov/condition/her...essure-palsies

[khushboo]

Option E (22q11.2) is correct. The symptoms described are consistent with velocardiofacial syndrome, part of the 22q11 syndrome (DiGeorge, Sedlackova, and velocardiofacial syndromes) caused by a three-megabase microdeletion at chromosome 22q11.

Option A (4p) is incorrect. Wolf-Hirschhorn syndrome is caused by deletion of 4p.

Option B (7q11) is incorrect. Williams syndrome is caused by microdeletion at 7q11.

Option C (15q11-12) is incorrect. Individuals with Prader-Willi syndrome and those with Angelman syndrome often have microdeletions at 15q11-12.

Option D (17p11.2) is incorrect. Individuals with Smith-Magenis syndrome have microdeletion at 17p11.2.

[ashishkabir]

Thanks Khushboo - if it wasn't for the fact that I knew the answer to this one I'd be completely lost if I was trying to guess.

[khushboo]

well i was not able to make out that its DiGeorge syndrome...

[ashishkabir]

Originally Posted by khushboo

well i was not able to make out that its DiGeorge syndrome...

That's okay I think - there's more than a couple of other things you know that I don't know

[Haisook]

Originally Posted by khushboo

well i was not able to make out that its DiGeorge syndrome...

Neither did I! I think DiGeorge comes to mind only when one hears about a thymus/immunity problem and hypocalcemia. I think it's useful to associate "Velocardiofacial syndrome" with this disease. It will help remind us of the other abnormalities found.

[step1an]

This mnemonic will be helpful....

DiGeorge syndrome = CATCH 22
Cardiac Abnormality (mostly tetralogy of Fallot)
Abnormal facies
Thymic aplasia
Cleft palate
Hypocalcemia.
22q11 chromosome deletion

[step1an]

Also found another ....


For Di George syndrome everything is 2 'di'

chromosome 22

2 organs -thymus and parathyroid

2 abnormalities -aplasia or hypoplasia

2 pouches -3 & 4

bifid uvula

2 facies -falt face like alcohol & fish like mouth-2 f's

2 systems involved -cardiovascular(ASD, VSD), ESOPHAGEAL ATRESIA

2 infections -viral &viral

2 ig -IgA ,IgE

DIAGNOSIS BY 2 H/P & PCR

Rx 2

- thymic transplant and bone marrow transplant

Not sure about all of the points mentioned. Plz point out if u find any mistakes...

[ashishkabir]

Yeah - I think the old Kaplan qbank used to use this sometimes - give you this facial description and then ask you what kind of hormone imbalance you'd see. Still - the other options in this question confused me for a bit too.

Thanks for the mnemonics - this question has the best description of a facial abnormality I've seen for anything in a long time... it takes like a minute just to decipher and imagine what they are talking about