Lecture 10 Flashcards
RBC inclusions
● RBC inclusions are nuclear or cytoplasmic remnants
●Normal mature RBCs have no major
cytoplasmic contents other than
Hemoglobin
All inclusions are abnormal –
‒ Reported as:
■ Occasional
■ Some
■ Many
RBC Inclusions
Visible on a Wright’s-stained smear:
Not Visible on a Wright’s-stained smear:
Visible on a Wright’s-stained smear also while using supervital staining:
● Howell-Jolly Bodies (HJB)
● Pappenheimer Bodies (PPH)
● Basophilic Stippling (BS)
● Cabot rings
Not Visible on a Wright’s-stained smear:
● Heinz Bodies
● Hgb H
● Reticulocytes ** precipitates RNA in wrights stain better with supervital staining (theyll be blue)
found within the red cell cytoplasm so when we see them under a microscope if it goes in and out of focus with the cell its inside it
Howell-Jolly Bodies
- fragment of denatured DNA
- Large, round
- Eccentric position
- Single (occ multiple seen)
- Stains dark blue to purple (dense basophilic staining little dot in RBC
- Rare HJB in normal blood is quickly removed by spleen
- EPO stimulates increased erythropoiesis which results in more HJB which can occur in diseases states
- Form via two mechanisms
Formation – Type 1
* Chromosome becomes detached from or fails to attach to mitotic spindle
* Chromosome left behind as nucleus is extruded
Formation –Type 2
* Abnormal fragmentation of nucleus before expulsion, leaves behind small nuclear fragment. The larger nucleus is expelled and the smaller fragments becomes the HJB
HJB-Associated Conditions
- Abnormal or accelerated erythropoiesis
* Megaloblastic anemia (high turn over where the nucleus development falls behind development of cytoplasm due to b12 or folate deficiency)
* Hemolytic anemias
* Thalassemia
* Myelodysplastic syndrome - Splenic atrophy
* Reduced function leaving HJB behind reduced filtering - Postsplenectomy
* Damaged or diseased spleen removed the body’s filter for abnormal RBC is gone
Pappenheimer Bodies
● Irregular clusters of small, fine and discrete iron granules -look like staph clusters
● Light to dark blue lining around the periphery
● One cluster but may see multiple clusters
-Errors in Hgb formation result in excess iron-filled mitochondria and degenerate ribosomes = damaged organelles
-Vacuole forms around damaged ribosomes and mitochondria forming an autophagosome
-Lysozymes digest vacuole leaving free iron and protein in cytoplasm
-if the vacuole isnt removed by splenic pitting, inclusion(s) remain in cell
-Iron not incorporated into Heme molecule
‒ Remains as Ferritin
‒ Hemosiderin is intracellular storage form of Iron= Pappenheimer bodies
- iron specific stain is used as a confirmatory test for PappenH
‒ Perl’s Prussian Blue
Target of stain called Siderotic granules (or Hemosiderin) - Confirmatory test for PPH
-Positive for iron but if without PPH then negative the RBC stains more red
Associated with any condition(s) of abnormal:
* Hemoglobin production or
* Errors in iron incorporation or leading to iron buildup
‒ Sideroblastic anemia
‒ Hemoglobinopathies (Sickle cell anemia)
‒ Thalassemia
‒ Postsplenectomy
‒ Hematochromatosis
‒ Meglaoblastic anemia
Basophilic Stippling
- Denatured /Precipitated RNA &/or mitochondria remnants
- Dark blue to purple, coarse and heavy punctate granules distributed evenly in cytoplasm (stippling effect)
- clinically significant when heavy if Fine and studded then they can be due to polychromasia or improper slide drying
- in conditions with defective or accelerated Hgb synthesis
Course Stippling
‒ Thalassemias ‒ Lead and other heavy metal poisoning
‒ Pryimidine 5’ nucleotidase deficiency
Fine stippling
‒ Liver disease ‒ Dyserythropoiesis Variable
‒ Megaloblastic anemias
Cabot Rings
- Rarely seen:
‒ Remnants of mitotic spindle
‒ Dark blue to purple or red
‒ Appear as a loop, ring or figure-eight, and may look like beads on a string - Associated with Megaloblastic anemia and Myelodsyplastic syndro
Heinz Bodies
Denatured Hemoglobin
* Found in mature RBCs
* Round, dark blue to purple granules after supravital stains - New Meth Blue composed of denatured precipitated hemoglobin
-found in periphery of RBC inner membrane
Heinz bodies consists of either:
1. Normal Hgb is denatured by oxidative stress
2. Abnormal, Hgb that has been precipitated
Associated with:
‒ G6PD deficiency
‒ Abnormal or unstable Hemoglobin
‒ Oxidant drugs/chemicals
‒ Some Hemoglobinopathies
BITE CELLS: because you cant see Heinz bodies on wright stain so you look for indicators like they are there
● If Bite cells are seen on a Wright’s PBF, then a Supravital stain is done to demonstrate Heinz bodies
Hemoglobin H
Precipitated Hemoglobin β chain tetramers
* Seen in Hemoglobin H disease
‒ Deletion of 3α-globin genes leads to formation of β chain tetramers= Hgb H
‒ Hgb H susceptible to oxidation forming precipitates of denatured Hgb
- Small, dark blue-purple granules
- Gives ‘golf ball’ or ‘raspberry’ appearance to RBCs Like a small baso
- Associated with: ‒ Hgb H Disease (α Thalassemia)
Reticulocytes
Follow up or ‘reflex’ test to
Increased Poly:
● Reticulocyte count
‒ Gives % Retic
‒ More accurate than assessing PBF
Manual- Supravital staining and manual counting
Automated methods- Immature
Reticulocyte Fraction (IRF) – use of
fluorescent/supravital dyes that stain nucleic acid in Retics before they are counted using fluorescence or absorbance and light scatter
Nucleated Red Blood Cell
- Orthochromic normoblast
‒ Can see earlier forms as well (severe disease)
● Round pyknotic nucleus
● Cytoplasm looks like a polychromatic RBC or mature RBC
● NOT a small Lymph
● NOT a ‘giant’ HJB
not normally seen in the peripheral blood and usually indicate bone marrow compensation to severe red cell destruction or loss.
-Reported as Occasional, Some or Many under Comments
-if there are more than 10 NRBC per 100 WBC then the count should be corrected
-all stages are all reported at NRBC
RBC Morphology- Organisms
Intra- and extra-cellular organisms:
● Any organism is reportable.
● Examine red cells for intra-cellular organisms (e.g. malarial parasites) and scan the areas between red cells for other stages or species.
● Report under COMMENTS as Occasional, Some or Many Intra- or Extra-cellular organisms seen. Report the species if possible.
Spleen
- Functions as body’s filter for circulating blood:
‒Culling
* Removes senescent or abnormal RBCs from circulation via
phagocytosis by macrophages
‒Pitting
* Remove inclusions/damaged RBCs (membranes) from circulation without destroying the cell, via movement through narrow passages of spleen and involves splenic macrophages
‒Platelet storage
* ~1/3 of total platelet count is sequestered in the spleen
* Not essential – often removed after injury (ruptured spleen) or to treat Hemolytic anemia(s)
Postsplenectomy Changes
CBC Results:
* WBC increase temporarily
* Platelet increased
‒ Increase begins 1-10 days post-splenectomy
‒ Peaks 1-3 weeks later
‒ Thrombocytosis may subside over weeks to months
Peripheral Blood Film:
* Poikilocytosis
‒ Abnormal cells usually removed by spleen are now ‘seen’
* Inclusions
‒ HJ Bodies
‒ Pappenheimers
‒ Rare NRBC
Risk of overwhelming Infection due to encapsulated organisms like Streptococcus pneumoniae
