The urea solubility test is used to detect deficiencies in which ...

[berenicecastro]

The urea solubility test is used to detect deficiencies in which factor?
 
  a. Fibrinogen
  b. Factor V
  c. Factor XII
  d. Factor XIII

Question 2

In what is a patient with the following coagulation test results most likely deficient?
 
  Test Result Reference Range
  Prothrombin time (PT) 17 seconds 11-15 seconds
  Partial thromboplastin time (PTT) 31 seconds 25-37 seconds
  Thrombin time (TT) 16 seconds 15-21 seconds
 
  a. Fibrinogen
  b. VII
  c. VIII
  d. X

[Alyson.hiatt@yahoo.com]

Answer to Question 1

ANS: D
The plasma from patients with a factor XIII deficiency forms weak clots that dissolve within 2 hours when suspended in a 5M urea solution because the clot has not been cross-linked by XIIIa.

Answer to Question 2

ANS: B
Factor VII deficiency shows a prolonged PT with a normal PTT result. A deficiency of fibrinogen ideally should prolong the PT, PTT, and TT. Factor VIII deficiency prolongs the PTT but not the PT and TT, whereas a factor X deficiency should prolong both the PT and PTT but not the TT.