Detecting and Evaluating Coagulation Inhibitors and Factor Deficiencies

Detecting and Evaluating Coagulation Inhibitors and Factor Deficiencies is organized by MediaLab, Inc.

Course Description:
Prolonged PT and aPTT results are caused by many different conditions. It is important for medical laboratory scientists to be able to distinguish between preanalytic causes, secondary clinical causes, and important and potentially dangerous causes such as coagulation factor deficiencies and circulating coagulation factor inhibitors. Upon completion of this course, you will be able to identify: the common causes associated with prolonged PT and/or aPTT results, when it is appropriate to perform a mixing study, how to perform and interpret mixing studies, how to differentiate between factor deficiencies and factor inhibitors, and further testing that can be done to confirm mixing study results.

Objectives:
• Determine various causes of an elevated prothrombin time or activated partial thromboplastin time result.
• Evaluate situations in which performing a mixing study would be appropriate.
• List the steps involved in a prothrombin time or activated partial thromboplastin time mixing study procedure.
• Correctly analyze and interpret mixing study results to distinguish a factor deficiency from a circulating inhibitor(s).
• Determine which, if any, further coagulation studies would prove helpful after obtaining mixing study results.

Course Outline:
• Introduction to Coagulation Inhibitors and Factor Deficiencies
    • Introduction: Coagulation Inhibitors
    • Coagulation Inhibitors
    • Introduction: Factor Deficiencies
    • Coagulation Inhibitors and Coagulation Screening Tests
• Evaluating prolonged prothrombin time and activated partial thromboplastin time test results
    • Coagulation Factors Monitored By the Prothrombin Time (PT) Test
    • Coagulation Factors Involved in the Activated Partial Thromboplastin Time (aPTT) Test
    • Elevations in PT or aPTT assays
    • Preanalytical Variables That Can Cause Falsely Elevated PT or aPTT Results
    • Summary of Initial Elevations in the PT and aPTT
    • Which of the following may produce a falsely prolonged aPTT test result?
• Performing a mixing study
    • Introduction to Mixing Studies
    • When To Perform a Mixing Study
    • Mixing studies may help to determine the presence of which of the following?
    • Mixing Study Test Principle
    • Mixing Study: Specimen Requirements
    • Performance of a Mixing Study
    • Performance of a Mixing Study, continued
    • Performance of a Mixing Study, continued
    • What is the ratio of patient plasma to pooled normal plasma that is usually used in the performance of a mixing study?
    • What is the minimum percentage of each coagulation factor that must be present in a patient's plasma to produce a normal PT and aPTT test result?
• Analyzing and interpreting mixing study results
    • Analyzing the Mixing Study Results
    • Interpreting the Mixing Study Results
    • Initial PTImmediate Mixing Study PTIncubated Mixing Study PT23 sec. 12 sec. 13 sec.Are the patient's mixing study results corrected or not corrected? ...
    • Analyzing the Mixing Study Results, continued
    • Analyzing the Mixing Study Results, continued
    • Mixing Study Methodology Differences
  • Case Study 1
    • Interpreting the Mixing Study Results: Case Study One
    • Case Study One, continued
    • Case Study One, continued
    • Case Study One, continuedWhich factor level(s) could be deficient?
  • Case Study 2
    • Interpreting the Mixing Study Results: Case Study Two
    • Case Study Two, continuedInitial aPTTImmediate aPTT Mixing StudyIncubated aPTT Mixing StudyReference Range86 sec. 87 sec.88 sec.21-34 sec. Is the aPTT...
  • Case Study 3
    • Interpreting the Mixing Study Results: Case Study Three
    • Case Study Three, continuedInitial aPTTImmediate aPTT Mixing StudyIncubated aPTT Mixing StudyReference Range63 sec. 26 sec.65 sec.21-34 sec.Has the aP...
• Determination of further coagulation studies
    • Further Analyses for Factor Deficiencies
    • Further Analyses for Factor Deficiencies, continued
    • Further Analyses for Factor Deficiencies: Factor Activity Curves
    • Treatment for Factor Deficiencies
    • Lupus Anticoagulant (LA)
    • Further Analyses for Coagulation Inhibitors: Lupus Anticoagulant
    • Further Analyses for Coagulation Inhibitors
    • Treatment for Coagulation Inhibitors
• References
    • References