USMLE forum
 
Archives
Step 1
Step 2 CK
Step 2 CS
Matching & Residency
Step 3
 
Forum
 
 
  <<   < *  Step 1  *  2004 Archives  *   >   >>  

* is tt same as bt
 #4333  
  - 05/27/04 00:39
 
  mumbai

A 5-year-old boy is being evaluated for recurrent epistaxis and other abnormal bleeding episodes, including excessive bleeding from the umbilical cord at birth. Laboratory studies reveal the following: decreased hemoglobin (with microcytic hypochromic red cell indices), normal platelet count, markedly prolonged prothrombin time (PT) and partial thromboplastin time (PTT), and unmeasurable thrombin time (TT). Platelet aggregation studies reveal a normal platelet response to ristocetin, but with other substances (including collagen, ADP, and epinephrine), this patient?s platelets exhibit a primary wave defect. Based on these findings, which of the following is the most likely diagnosis?


Answer Choices : Correct answer : Your answer
A. Afibrinogenemia
B. Bernard-Soulier syndrome
C. Glanzmann?s thrombasthenia
D. Gray platelet syndrome
E. Wiskott-Aldrich syndrome

 
Report Abuse

* Re: is tt same as bt
#15828
   - 05/27/04 11:59
 
  mumbai

any suggestion
 
Report Abuse

* Re: is tt same as bt
#15829
   - 05/27/04 12:16
 
  amruta

no tt and bt are two different things. I am not sure what the answer is on this one, but D,E can be ruled out as there is no problem with the paltelets....the problem lies with the coagulation factors as evidenced by the increased pt and ptt.

Also bernard soulier can be ruled out as they tend to have decreased platelet counts.

A is due to a deficiency in fibrin...so this is an unlikely answer.
I don't know for sure.....maybe this info i porvide can help you decide. Sorry.
 
Report Abuse

* Re: is tt same as bt
#15830
   - 05/27/04 12:31
 
  amruta

disreagrd what I wrote. I don't have my concepts clear and need to reread this chapter. Sorry if I confused you.
 
Report Abuse

* Re: is tt same as bt
#15831
   - 05/27/04 12:35
 
  cheerkut

consider
clotting in 3 steps

step1 ----formation of thromboplastin
via activation of intrinsic pathway
tested with APTT
factors involved 8,9,11,12
normal 25 to 40 sec
step 2---- formation of thrombin from prothrombin
via factors 5,7.
tested with PT
normal 12 to 14sec
step 3----formation of fibrin from fibrinogen
tested with TT
normal 15 to 20 sec

bleeding time measures both the vascular and the platelet factors involved in clotting
hence BT is 4 to 8 minutes.

 
Report Abuse

* Re: is tt same as bt
#15832
   - 05/27/04 14:23
 
  mash

afibrinogenemia
 
Report Abuse

* Re: is tt same as bt
#15833
   - 05/27/04 18:52
 
  doc

afibrinogenemia....for sure....factor 13 def..!!
 
Report Abuse

* Re: is tt same as bt
#15834
   - 05/28/04 10:48
 
  mumbai

doc can u explain it pls
 
Report Abuse

* Re:is tt same as bt
#212220
  billll - 11/07/05 09:42
 
  agree?  
Report Abuse

* Re:is tt same as bt
#212221
  billll - 11/07/05 09:45
 
  I feel this is Glanzmann... any discussions?  
Report Abuse

* Re:is tt same as bt
#212312
  hkv - 11/07/05 11:56
 
  bernard is ruled out as the Platelet aggregation studies reveal a normal platelet response to ristocetin...

glanzmann, defect in platelet aggregation... must be the answer.
 
Report Abuse

          Page 1 of 2     [Next >]     [Last >>]

[<<First]   [<Prev]  ... Message ...  [Next >]   [Last >>]
 

 

 

Google
  Web USMLEforum.com
 

Step 1 Step 2 CK Step 2 CS Matching & Residency Step 3
USMLE Forum ArchivesUSMLE LinksUSMLE Forum Home