RBC morphology Flashcards
Primary causes of macrocytic anemia?
Regenerationà folic acid and vit. B12 deficiency.
What can be associated w/ the presence hypochromic red cells?
Increase central palor b/c less hemoglobin à Fe def. anemia
What can polychromasia be indicative of?
That the bone marrow is responding producing immature red cells
in the periphery – ex. From blood loss/ blood destruction
• the blue color results from organelles (ribosomes, mitcochondria)
still present in immature cells.
What shape are llamas red cells?
Oval red cells
What is the term punched out or bowl shape RBC?
Not a true hypochromasia- Red cell tries to fit in a small capillary bed, the shape changes and you see an enlarged “central palor” but there is a thick ring w/in it. – cell membrane doesn’t snap back. No clinical significance.
What are the important erythrocyte shapes?
spiculated red cells (acanthocytes, echinocytes, keratocytes,
fragmented red cells (Schistocytes) and spherocytes.
What is an echinocyte and what causes it?
Numerous short spicules (crenation- can occur b/c of slow drying blood film- in vitro in humid places – look to see if change is uniform
• In vivo- electrolyte imbalance (a cat w/ diarrhea causing electrolyte imbalance w/ almost always see it on a blood film; non specific kidney dz, and rattle snake envenomation (can take up to 18 hrs to see the change, but will go away in about 72 hours
o Rattle snake envenomationà when the RBC is recovering, can the spicules can be removed before the central palor is restoredà can be confused w/ a shistocyte. (looks polychromatophilic)important to know the history!
What is an acanthocyte?
Few unevenly distributed projections due to changes in lipid
concentrations in the RBC membrane. Caused by cats w/ hepatic lipidosis and dogs w/ hemangiosarcoma (check for other signs- polycromasia of other RBC and shistotcytes!!
• Spicules are larger w/ little knobs.
What is a Schistocyte?
RBC fragments. Caused due to intravascular trauma (DIC, vascular tumor) or FE def. anemia.
o If you see a lot of red cell fragmentation- see if animal is thrombocytopenic. – could make you think animal is DIC.
o w/ DIC- fibrin strands act as clotheslines and cause RBC morphology to change
what is a karatocyte?
One or 2 quite long spicules often formed by breaking open of
“blisters”- purse cells. Most common disorder you see this in is Fe def. anemia.
o Don’t see a lot of hypochromisia in cats w/ Fe def. anemia like all other species. If don’t have microcytosis but w/ keratocyte- think of another dx than fe def. anemia.
What is a spherocyte?
• RBC appear small, lack central palor but volume is normal. The
presence of a spherocyte suggest IMHA. Difficult to recognize them
outside of dogs
• You can have imperfect spheres (where the spherocyte is not yet
completely voided of a central palor. Check neighboring cells. Can
miss a dx of IMHA
• Spherocyte forms when macros and complement act on the RBC
membrane and phagocytize a portion of the RBC membrane so no longer a biconcave disk
o Can cause intravascular and extravascular hemolysis.
What is an eccentrocyte?
Shifting of the Hemoglobin to one side of the cell resulting in a clear zone outlined by a membrane. Often cause is oxidative damage w/ ingestion of onion or w/ Heinz body formation
What are leptocytes, codoctyes?
Little dx significance. Target cells, bowl cells, folded cells.
What are stomatocytes?
Mouth like clear area in center of RBC. Few usually insignificant.
Hereditary stomatocytes in alaskan malamutes, miniature schnauzers, and Drentse partrijshond canine breeds
What are examples of structures that can be in or on RBC?
Heinz body formation, basophilic stippling, nucleated RBc and
Howell jolly bodies, parasites, and viral inculsions
