HEMA LEC - Hemolytic Anemias due to Extrinsic/Non-immune defects Flashcards
All cause a normocytic/normochromic anemia caused by trauma to the RBC. All are required disorders that cause intravascular hemolysis with schistocytes and thrombocytopenia.
Hemolytic Anemias due to Extrinsic/Non-immune defects
- Microangiopathic haemolytic anemias (MAHAs) [3]
DIC
TTP
HUS
1.) Systemic clotting is initiated by activation of the coagulation cascade due to toxins or conditions that trigger release of procoagulants (tissue factor). Multiple organ failure can occur due to clotting.
Disseminated Intravascular coagulation (DIC)
2.) Fibrin is deposited in small vessels, causing RBC fragmentation.
Disseminated Intravascular coagulation (DIC)
- ) Occurs most often in children following a gastrointestinal infection (e.g., E. coli)
- ) Clots form, causing renal damage.
Hemolytic uremic syndrome (HUS)
- ) occurs most often in adults.
- ) It is likely due to a deficiency of the enzyme ADAMTS 13 that is responsible for breaking down large von Willebrand factor multimers. When multimers are not broken down, clots form, causing RBC fragmentation and central nervous system impairment.
Thrombotic thrombocytopenic purpura (TTP)
responsible for breaking down large von Willebrand factor multimers
ADAMTS 13
Transient Hemolytic anemia that occurs after forceful contact of the body with hard surfaces (e.g., marathon runners, tennis players).
March hemoglobinuria