3.22 STROM Mechanisms for Hemolytic Anemias

Question 1

Malaria

Answer 1

• Disease of poor

- usually diagnosed by review of the ps in the right context, someone who has recently traveled

Question 2

Babesia

Answer 2

• Transmitted by ticks and is endemic in the northeastern US

- much milder course than malaria

Question 3

C. Perfringens

Answer 3

Component of normal skin flora which can secrete toxin that results in hemolysis

• Can also cause tissue destructive form sepsis called GAS GANGRENE
• Hemolytic anemia is usually severe and fatal when it occurs
• Lab may think ps is a bad specimen

Question 4

Autoimmune

Answer 4

• Abs specific for red cell surface antigens
• Macros in RES can clear
• Sometime macros just take a bite out
• Microspheres: decreases MCHC, usually easy to see in ps
• Can also have complement fixation-MAC complex
• Can see nucleated RBCs with any hemolytic anemia if it is severe enough b/c BM is pushing cells out fast to try and compensate

Question 5

Red Cell aggulation

Answer 5

Can usually be dissociated by warming the specimen

• will cause an inaccurate, low RBC and therefore an incorrect, low HCT
• Can be caused by Cold Abs in specimens

Question 6

Warm vs Cold abs

Answer 6

-Warm autoimmuno hemolytic anemia is often seen in association with malignancies (not specific) and generally carry a poorer prognosis
Col agglutinins are occasionally seen in association with malignancies, but are more commonly a complication of infectious diseases or of a broader systemic autoimmune condition like SLE

Question 7

VWF auto-hemolytic anemia

Answer 7

• If cables are too long, too much platelet adherence takes place, resulting in thromboses in small and medium sized vessels
• microangiopathic hemolysis
• Red cell lysis resulting from cords of fibrin strung across the small vessels, slicing RBCs into bits as they come flyingby
• AdamTS13 is enzyme responsible for trimming vWF
• abs made for the protease can lead to TTP
• Schistocytes