NURS 6501: Final Exam: Please contact Assignment Samurai for help with NURS 6501: Final Exam or any other assignment. Email: assignmentsamurai@gmail.com   A patient presents with spontaneous bruising and petechiae. Laboratory tests reveal thrombocytopenia and anemia, with blood smears showing fragmented red blood cells. The patient has no history of bleeding disorders. What is the most likely underlying cause of this patient’s signs and symptoms? Group of answer choices

• Disseminated intravascular coagulation (DIC)
• Deficiency of ADAMTS13 enzyme
• von Willebrand Disease
• Hemophilia B

The correct answer is: Deficiency of ADAMTS13 enzyme   Explanation: The patient’s presentation—spontaneous bruising, petechiae, thrombocytopenia, anemia, and fragmented RBCs (schistocytes)—is classic for thrombotic thrombocytopenic purpura (TTP), caused by:

• Severe deficiency of ADAMTS13 enzyme (due to autoantibodies or genetic mutation).
• This leads to uncleaved ultra-large von Willebrand factor (vWF) multimers, causing microthrombi in small vessels.
• Microangiopathic hemolytic anemia (MAHA) occurs due to RBC shearing by fibrin strands.

Why Not the Others?

• Disseminated intravascular coagulation (DIC):
  • Also causes thrombocytopenia + schistocytes, but typically occurs in sepsis, trauma, or malignancy (not spontaneous).
  • Lab findings include prolonged PT/aPTT, low fibrinogen, and elevated D-dimer (unlike TTP).
• von Willebrand Disease (vWD):
  • Causes mucocutaneous bleeding but not thrombocytopenia or schistocytes.
• Hemophilia B:
  • Presents with joint/muscle bleeding (not bruising/petechiae) and prolonged aPTT, but normal platelets and RBC morphology.

Key Diagnostic Test for TTP:

• ADAMTS13 activity <10% confirms TTP.
• Treatment: Plasma exchange (PLEX) is urgent to remove autoantibodies and replenish ADAMTS13.

Thus, ADAMTS13 deficiency (TTP) is the most likely diagnosis.