Dear Colleagues:
Newborn with 55% blasts in PBL. Flow differential dx is Transient abnormal myelopoiesis (TMD) associated with Down Syndrome and/or Acute megakaryoblastic leukemia (AMKL).
Clinicians want us to r/o or confirm Trisomy 21 AND if +21 is limited to the Blasts only. As per Clinical Geneticist baby has absolutely no Down Syndrome features, and pediatric oncologists say baby has no organomegaly that would be associated with AMKL.
FISH RESULTS:
Interphase (only) form a Direct Harvest: 45% Trisomy 21
Interphase (only) from a 72 hour stimulated culture: 44% Trisomy 21
CHROMOSOME ANALYSIS (50 cell study):
UNSTIMULATED 24 AND 48 hour cultures: 95% Trisomy 21 ( no leukemia associated structural anomalies seen)
STIMULATED 72 hour Cultures:
Only 5% Trisomy 21 and 95% Disomy 21
I am trying to understand the discrepancy between the stimulated and unstimulated chromosome analyses results.
I am also recommending FISH Study on a buccal swab specimen. I have no way of letting the physicians know if the +21 is limited to the blasts cells based on the methodology used.
Like to know your thoughts on this .
Thank you all.
Best,
Ramesh
Hi Ramesh,
Interesting case!
The difference between unstimulated and stimulated blood cells is probably reflecting the difference between a very high B-cell content (blasts with a trisomy 21) in unstimulated cells and an increasing number of T-cells in the stimulated cultures since the phytohemagglutinin present in the medium typically stimulates the T-lymphocytes to grow and not the B-cell population. For that reason you see much less trisomy 21 cells in metaphase cells because they come from dividing T-cells. So this emphasizes that the trisomy 21 is present only in B-cells and not in T-cells. To really exclude a congenital trisomy 21 the buccal swab FISH indeed is a good idea next to a skin biopsy.
Best ,
Dominique
Dr. D. Smeets, clinical laboratory geneticist
Theme Fertility and Pregnancy
Radboud University Medical Centre, Nijmegen
--
You received this message because you are subscribed to the Google Groups "Cytogenetics methods and trouble-shooting Forum" group.
To unsubscribe from this group and stop receiving emails from it, send an email to
cytogenetics-methods-and-t...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/cytogenetics-methods-and-trouble-shooting/MN2PR08MB6271FA5319DB68E29D369376CF700%40MN2PR08MB6271.namprd08.prod.outlook.com.
De informatie in dit bericht is uitsluitend bestemd voor de geadresseerde. Aan dit bericht en de bijlagen kunnen geen rechten worden ontleend. Heeft u deze e-mail onbedoeld ontvangen? Dan verzoeken
wij u het te vernietigen en de afzender te informeren. Openbaar maken, kopiëren en verspreiden van deze e-mail of informatie uit deze e-mail is alleen toegestaan met voorafgaande schriftelijke toestemming van de afzender. Het Radboudumc staat geregistreerd
bij de Kamer van Koophandel in het handelsregister onder nummer 41055629.
The content of this message is intended solely for the addressee. No rights can be derived from this message or its attachments. If you are not the intended recipient, we kindly request you to delete the message and inform the sender. It is strictly prohibited
to disclose, copy or distribute this email or the information inside it, without a written consent from the sender. Radboud university medical center is registered with the Dutch Chamber of Commerce trade register with number 41055629.
Hello:
Thank you. My understanding is that AMKL is a Myeloid Stem Cell-Megakaryocytic in origin and not B-cell lymphoid.
I will keep you all posted when I have the Buccal Swab FISH result.
Best,
Ramesh
From: cytogenetics-methods...@googlegroups.com <cytogenetics-methods...@googlegroups.com>
On Behalf Of Dominiqu...@radboudumc.nl
Sent: Thursday, July 30, 2020 4:34 AM
To: cytogenetics-methods...@googlegroups.com
Subject: RE: Mos +21 in Newborn with 55% Blasts
CAUTION: This email comes from an external source; the attachments and/or links may compromise our secure environment. Do not open or click on suspicious emails. Please click on the “Phish Alert” button on the top right of the Outlook dashboard to report any suspicious emails. |
To view this discussion on the web visit https://groups.google.com/d/msgid/cytogenetics-methods-and-trouble-shooting/dbc09084b31748aa955cc5acef1beec5%40Umcexchp03.umcn.nl.
To view this discussion on the web visit https://groups.google.com/d/msgid/cytogenetics-methods-and-trouble-shooting/dbc09084b31748aa955cc5acef1beec5%40Umcexchp03.umcn.nl.
HI Pat:
Thank you. I understand your points. The blasts have gone down from 55% to 30% now. Unable to find a Lab that offers Buccal Swab FISH Test to rule Tisomy 21. Mayo and Quest both said that they don’t offer this test.
Take care,
Ramesh
From: cytogenetics-methods...@googlegroups.com <cytogenetics-methods...@googlegroups.com>
On Behalf Of Pat Cammarata
Sent: Thursday, July 30, 2020 9:12 AM
To: cytogenetics-methods...@googlegroups.com; Dominiqu...@radboudumc.nl
Subject: RE: Mos +21 in Newborn with 55% Blasts
CAUTION: This email comes from an external source; the attachments and/or links may compromise our secure environment. Do not open or click on suspicious emails. Please click on the “Phish Alert” button on the top right of the Outlook dashboard to report any suspicious emails. |
Good morning,
To view this discussion on the web visit https://groups.google.com/d/msgid/cytogenetics-methods-and-trouble-shooting/1888836831.9629.1596114717871%40connect.xfinity.com.
It is also possible to perform a quick QF-pcr test on DNA isolated from a buccal swab. We do that all the time for prenatal DNA samples. If the trisomy 21 is not constitutional you will not trace it in the swab and the results are available within 24 hours.
Regards,
Dominique
To view this discussion on the web visit https://groups.google.com/d/msgid/cytogenetics-methods-and-trouble-shooting/MN2PR08MB62716D990505AC642481777FCF4D0%40MN2PR08MB6271.namprd08.prod.outlook.com.
Thank you Dominique.
Ramesh
To view this discussion on the web visit https://groups.google.com/d/msgid/cytogenetics-methods-and-trouble-shooting/71024e39dfe844e5a17045b76940081a%40Umcexchp03.umcn.nl.
Hi Sara:
Thank you.
Ramesh
To view this discussion on the web visit https://groups.google.com/d/msgid/cytogenetics-methods-and-trouble-shooting/2112661160.259842.1596644857205%40mail.yahoo.com.