What is used to activate protein C in the chromogenic assay used ...

[ericka1]

What is used to activate protein C in the chromogenic assay used to determine its concentration?
 
  a. Partial thromboplastin
  b. A specific snake venom
  c. Kaolin
  d. Heparin

Question 2

A 37-year-old female patient has a PTT of 76 seconds (reference range, 25 to 37 seconds). Her plasma is mixed 1:1 with normal plasma. An immediate PTT performed on the mix is 74 seconds. Which of the following is the most likely diagnosis?
 
  a. Hemophilia A
  b. Factor VIII inhibitor
  c. Intrinsic factor deficiency
  d. Lupus anticoagulant

[bubulittle310@msn.cn]

Answer to Question 1

ANS: B
A specific snake venom is used to activate protein C in its chromogenic assay.

Answer to Question 2

ANS: D
A prolonged PTT that remains prolonged after an immediate repeat of the PTT on the 1:1 mix is seen in patients (either male or female subject) with the lupus anticoagulant. A patient with hemophilia A would most likely be a male subject (female hemophilia A is rare). In addition, the immediate 1:1 mix should correct, as it also would with an intrinsic factor deficiency. The PTT on an immediate 1:1 mix in the presence of a factor VIII inhibitor would also essentially correct.

[ericka1]

TYSM

[scikid]

Thanks for the timely response, appreciate it