Lecture 11 RBC Morph Flashcards
(27 cards)
poikilocytosis
a variation in RBC shape, not a very specific term
spherocytes
- rbc that are small, round, dense, no central pallor
- appear hypochromic but not more Hgb
- increase MCHC if moderate to marked spherocyte present
- MCV not affected
- irreversible
causes: abnormality of the RBC membrane (genetic), autoimmune disease
artefact: feathered end of the smear
possible conditions associated with spherocytes
- hereditary spherocytosis
- immune hemolytic anemia
- severe burns
- MAHA
echinocytes
- RBC w/ short, even blunt projections evenly spaced over entire surface, obvious central pallor
- reversible, cell is normochromic just spikey
- AKA Burr Cells
Causes: change in tonicity of intravascular fluid ([] of solutes in vessels]) –> RBC in hypertonic –> shrink!
Artefact: crenated cells
- thick smear, old blood (4 hours), short draw (EDTA), slow drying of smear, humid
possible associated conditions with echinocytes
- uremia
- pyruvate kinase deficiency
- liver disease
acanthocytes
-few irregular & uneven projections + varying lengths
- smaller dense RBC w/ no pallor
- AKA Spur Cell
Causes:
- changes in lipid membrane
- severe liver disease
- abetalipoproteinemia
- McLeod syndrome
how can spherocytes form?
Intrinsic Abnormalities:
- deficiency of spectrin, ankyrin –> microvesicle forms and membrane loss –> forms bc surface area decreases –> HEREDITARY spherocyto.
Immune Hemolysis:
- Ab attach to red cell (complement if enough IgG), Fc receptor binds to Ab, Ag-Ab complex forms and RBC membrane fragments, leaving microspherocyte
microspherocyte
- very small RBC (tiny!!)
- due to severe burns
- microangiopathic hemolytic anemias (MAHA)
- also see w/fragmented cells
Elliptocytes/ Ovalocytes
- RBC shaped as pencils
- E: cigar shaped
- O: egg shaped
Cause:
- mechanical weakness of membrane skeleton
- membrane protein abnormalities (spectrin)
Conditions:
- hereditary elliptocytosis
- thalassemia major
- IDA
- megaloblastic anemias (oval macrocytes)
Tear Drop Cells
- pear shaped with one long spicule (blunt or round tip)
- AKA dacryocytes
Cause:
- RBC inclusion & pitting action of spleen
- patients w/ abnormal spleen or BM vasculature
- macrocytic disorders (pernicious anemia) navigating normal spleen or BM
Conditions:
- primary myelofibrosis
- megaloblastic anemias
- thalessemia
Target Cells
- bullseye appearance of Hgb
- codocytes/leptocytes
Causes:
- abnormal membrane lipid composition (high lipid diet) that increase surface membrane to volume ratio altering membrane
- decrease [] of hgb in RBC (abnormal Hgb)
- HAPPENS OUTSIDE OF PT
Conditions:
- hemoglobinopathies
- thalassemia
- liver disease
Stomatocytes
- central pallor that resembles mouth
- uniconcave but normochromic
- hydrocyte
Causes:
- membrane protein defect (abnormal cation permeability)
- changes in environment
Conditions:
- hereditary stomatocytosis
- alcoholism
- liver disease
- Rh null phenotype
Sickle Cells
- pointed projections, rigid & inflexible
- drepanocytes
2 forms:
Holly Leaf –> oat/boat shape, reversible, most sickle cells
Crescent –> started as HL, irreversible, due to repeated sickling episodes
Causes:
- abnormal Hgb S (single AA sub)
- low O2 or pH, Hgb S will polymerize and form shapes that deform RBC
Conditions:
- Homo Hgb S disease
- Hgb C-Harlem
Fragmented Cells
- RBC w/ membrane damage
- it is a type of category of morphologies
Schistocytes
- RBC w/ pieces of membrane missing forming a fragment with no central pallor
Conditions:
- microangiopathic hemolytic anemia
- severe burns
- renal graft rejection
Blister Cells
- RBC in the shape of a purse
Causes:
- formed by pitting action of spleen to remove inclusion
Conditions:
- oxidative hemolysis of G6PD deficiency
- less commonly in MAHA
Hemoglobin Crystals
Hgb C
- inherited AA substitutions of BETA chains = mutated beta chains = Hgb C
- dark red, hexagonal shape
Hgb SC
- inherited AA sub of BETA chains = mutated beta chains = Hgb C and Hgb S
- 1-2 finger like projections, cell may be folded
Hgb H
- AA sub of ALPHA chains = less alpha chains = Hgb H
- multiple evenly dispersed granules
RBC Inclusions
- elements or small bodies within the RBC
- spleen is slacking
- some can be seen with wright stain and some supra-vital
Heinz Bodies
- RBC with denatured Hgb present
- precipitated abnormal/defective Hgb
- must use supravital stain to detect
Conditions:
- unstable Hgb
- some hemoglobinopathies
- some erythrocyte enzyme deficiencies (G6PD)
Basophilic Stippling
- stippling (numerous blue inclusions) throughout cell
- fragments of RNA
- see in mature RBCs and polychromatic cells
Conditions:
- lead intoxication
- thalassemia
- abnormal heme synthesis
Howell-Jolly Bodies
- RBC w/ small smooth round dark purple spheres
- fragments of DNA or chromosome
- remnants of nuclear DNA before expulsion
- seen in NRBCs/ RBC
- usually single inclusion but may be more
Conditions:
-splenectomy/hyposplenism
- megaloblastic anemia
- hemolytic anemia
Pappenheimer Bodies
- small dark purple inclusions
- usually irregular - varing in sizes, usually creating a cluster
- aggregates of iron & protein
- mature RBC w/ PB –> siderocytes
- if suspected, use iron stain (prussian blue)
Conditions:
- sideroblastic anemia
Conditions:
-splenectomy/hyposplenism
- megaloblastic anemia
- hemolytic anemia
Cabot Rings
- delicate thread like structures present
- nuclear remnants (mitotic spindle)
- VERY RARE, dont confuse/ malaria
Conditions:
- myelodysplastic syndrome
- megaloblastic anemia
Parasites
Malaria
- plasmodium
- single celled protozoan
- ring ish shape
Microfilariae
- filarial worms
