Hematology Flashcards
RBC (m)
4.5-5.5 x 10⁶ / uL (mm³)
RBC (f)
4.0-5.0 x 10⁶ / uL (mm³)
WBC
4.5-11.0 x 10³ / uL (mm³)
HGB (m)
14.0-17.4 g/dL
HGB (f)
12.0-16.0 g/dL
HCT (m)
42-52%
HCT (f)
36-46%
MCV (mean corpuscular volume)
80-100 fL
MCH (mean corpuscular hemoglobin)
28-34 pg
MCHC (mean corpuscular hemoglobin concentration)
32-36 g/dl
PLT
150-400 x 10³ / uL (mm³)
RDW (red cell distribution width)
12-16
MPV (mean platelet volume)
6.8-10.2 fL
Rule of 3
RBCs X 3 = HGB and HGB x 3 = HCT
MCV Calculation
HCT / RBC x 10
MCH Calculation
HGB / RBC x 10
MCHC Calculation
HGB / HCT x 100
WBC Critical Values
< 2.0 x 10³ / uL (mm³)
-or-
> 50.0 x 10³ / uL (mm³)
HGB Critical Values
< 7.0 g/dL
HCT Critical Values
< 21.0%
PLT Critical Values
< 20 x 10³ / uL (mm³)
-or-
> 1000 x 10³ / uL (mm³)
nRBC Threshold
5 / 100 WBC
WBC Flag: H or L
If critical, call floor and document;
Perform a WBC diff
WBC Flag: * and/or R
Consider/investigate the following:
* nRBCs – do diff and if >5 nRBCs/100 WBCs, correct WBC count and diff absolute values
* Large platelets – review smear and note if present
* Clumped platelets – review smear and note if present
* Clots - If none of the above are present, assume sample is clotted and redraw sample
RBC Flag: H or L
No action unless MCHC Flagged H, indicating cold agglutinins
Response to Cold Agglutinin
Warm specimen and rerun
HGB Flag: H or L
If critical, call floor and document;
If MCHC also flagged H, consider the following:
* Lipemia/icterus (indicated by false increase in Hgb without agglutination pattern); perform plasma blank/saline replacement and correct values
* Spherocytes; examine peripheral smear and document
* Cold agglutinins (pattern of low RBC, high MCV and high MCHC); warm sample and rerun
* Instrument malfunction – if none of the above are present; problem solve instrumentation
*super elevated white cells
HGB Flag: Delta Δ
Check surgery and transfusion records (could have gone up or down) and document; if no explanation for change, call floor
HCT Flag: H or L
If critical, call floor and document
HCT Flag: Delta Δ
Check surgery and transfusion records (could have gone up or down) and document; if no explanation for change, call floor
MCV Flag: H or L
Review smear, confirm macrocytes or microcytes, respectively;
If MCHC also flagged H and RBC flagged L, consider cold agglutinins
MCV Flag: Delta Δ
Patient likely misidentified; redraw sample
MCH Flag: H or L
No action necessary
MCHC Flag: H
Consider:
* Lipemia/icterus (indicated by false increase in Hgb without agglutination pattern); perform plasma blank/saline replacement and correct values
* Spherocytes; examine peripheral smear and document
* Cold agglutinins (pattern of low RBC, high MCV and high MCHC); warm sample and rerun
* Instrument malfunction – if none of the above are present; problem solve instrumentation
MCHC Flag: L
May observe smear for presence of hypochromia (not always required)
PLT Flag: H or L
If critical call floor and document;
If < 50 x 10³ / uL or > 1000 x 10³ / uL - Pathology Review
PLT Flag: R, *, Abnormal Histogram
Do platelet estimate on smear; if matches count, report value; if does not match count, perform manual platelet count
WBC Diff Flag: H or L
Perform manual differential;
Pathology review if absolute neutrophils (segs + bands) is less than 1.5 x 10³ / uL
WBC Diff Flag: */R
Perform manual differential
Segs (% and absolute)
40-60%
2.5-6.0 x 10³ / uL
Band (% and absolute)
0-5%
0-500 / uL
Lymphs (% and absolute)
20-40%
1.0-4.0 x 10³ / uL
Eos (% and absolute)
1-3%
50-300 / uL
Monos (% and absolute)
4-8%
200-800 / uL
Myelocytes (% and absolute)
0%
0 / uL
Basos (% and absolute)
0-1%
0-100 / uL
Immature Granulocytes (IG) (% and absolute)
0-1%
0-100 / uL
-cytosis
Elevated count
-cytopenia
Reduced count
Neutrophilia
Elevated neutrophils (either absolute or relative)
Criteria for Pathology Review
- Presence of blasts or lymphoma cells
- Absolute neutropenia (<1.5 x 10³ / uL)
- Platelet count (< 50 x 10³ / uL) or (> 1000 x 10³ / uL)
- Questionable cells/morphology - include description in report
Neutropenia
Reduced neutrophils (either absolute or relative)
Normocytes
RBCs with normal cell volume
Macrocytes
RBCs with increased cell volume
Microcytes
RBCs with decreased cell volume
Anisocytosis
Increased variability in RBC size (RDW > 16)
Acanthocytes
“Spur cells”. Associated with:
- Severe liver disease
- Splenectomy
Schistocytes
RBC Fragments. Includes “bite cells” and “blister cells”. Associated with:
- Hemolytic anemia
- Sever burns
- Renal graft rejection
Echinocytes
“Burr cells”. Associated with:
- Uremia
- Hemolytic anemia
- Neonates
Spherocytes
Spherical RBCs (no biconcave disk shape)
- No central pallor
- Suspect when high MCHC but normal RBC and MCV
Associated with:
- Severe burns
- Some hemolytic anemias
- Hereditary spherocytosis
Codocytes
“Target cells”. Associated with:
- Hemoglobinopathies,
- Thalassemia
- Iron deficiency anemia
- Splenectomy
Drepanocytes
Sickle Cells
Ovalocyte
Oblong RBCs, Length <2x the Width
- Associated with megaloblastic anemia (macro-ovalocytes)
- Can be hereditary
Elliptocyte
Oblong RBCs, Length >2x the Width. Associated with:
- Thalassemia major
- Iron deficiency anemia
- Can be hereditary
Dacryocytes
“Teardrop Cells”
- must ‘point’ in different directions, otherwise suspect artifacting
- Thalassemia
- Myelophthisic anemia
- Extramedullary hematopoiesis
Stomatocytes
“Mouth cells”
- Slit-like central pallor, not circular
- Common artifact of smear if only a few
Associated with:
- Alcoholism
- Liver disease
- RH null phenotype
- Can be hereditary
Rouleaux
“Stacked coins”
- Only call if found in the normal counting area (near the feathers)
Mentzer Index
MCV / RBC
Mentzer Index Interpretation
> 14 = iron deficiency
12-14 = indeterminate
< 12 = thalassemia trait
TAILS Anemias
Microcytic/hypochromic Anemias including:
- Thalassemia
- Anemia of chronic disease
- Iron deficiency
- Lead poisoning
- Sideroblastic anemia (congenital)
Howell-Jolly Bodies
Single eccentric dot, made of DNA. Associated with:
- Splenectomy
- Megaloblastic anemia
- Hemolytic anemia
Basophilic Stippling
Numerous small dots, made of RNA. Associated with:
- Lead poisoning
- Thalassemia
- Abnormal heme synthesis
Pappenheimer Bodies
Clustered eccentric light blue dots, made of iron. Associated with:
- Splenectomy
- Hemolytic anemia
- Sideroblastic anemia
- Megaloblastic anemia
- Hemoglobinopathies
Hypervolemia
Increased total blood volume
Hypovolemia
Decreased total blood volume
Functional Classifications of Anemia
- Survival Defects
- Proliferation defects
- Maturation defects
Morphological Classifications of Anemia
- Microcytic/Hypochromic
- Macrocytic/Normochromic
- Normocytic/Normochromic
Intrinsic vs Extrinsic Survival Defects
Intrinsic - hereditary abnormalities
Extrinsic - external injuries to the RBC
Intravascular Hemolysis
Lysis in vessels
Extravascular Hemolysis
Lysis in tissues (esp. the spleen)
Macrocytic/Normochromic Anemias include
- Megaloblastic anemia (asynchrony)
- Liver disease
- Hemolytic disease that elevates polychromia
Normocytic/Normochromic (non hemolytic) anemia includes
- Blood loss
- Endocrine dysfunction
- Renal disease
- Aplastic anemia
- RBC aplasia
- Myelophthisic anemia
DAT
Direct Antiglobulin Test (antibody to RBCs)
AHT
Anti-human globulin Test (antibody to RBCs)
Hemoglobin Electrophoresis
Cellulose Acetate at pH 8.4
- A (accelerated)
- F (fast)
- S (slow) – same distance as D
- C (crawls) – same distance as A2
Citrate Agar at pH 6.2
- F | D/A2/A | Origin | S | C
Normal Hemoglobin Ratios
97% A
2-3% A2
<1% F
Sickle Cell Anemia Hemoglobin Ratios
85-100% S
5-15% F
Sickle Cell Trait Hemoglobin Ratios
50-60% A
35-45% S
<1% F
Slightly increased A2
Hgb C Disease Hemoglobin Ratios
> 90% C
Slight increase in F
Hgb C Trait Hemoglobin Ratios
60-70% A
30-40% C
Hgb SC Disease Hemoglobin Ratios
50% S
50% C
Slightly increased F
Hgb E Hemoglobin Ratios
90% E
Variants of ß-Thalassemia Major (most to least severe)
ߺ/ ߺ (homozygous)
ß+/ ߺ (heterozygous)
ß+/ ß+ (homozygous)
ߺ gene
completely blocked production of Hgb ß chain
ß+ gene
partially blocked production of Hgb ß chain
ß-Thalassemia Major Hemoglobin Ratios
Up to 90% F
Increased A2
Low A
Hemoglobin H
Tetrads of Beta hemoglobin chains, precipitates into Heinz bodies, high O2 affinity
- Associated with α-Thalassemia
Hemoglobin Barts
Tetrads of Gamma hemoglobin chains, extreme O2 affinity
- Associated with α-Thalassemia Major (Hydrops Fetalis)
- Usually results in stillbirth
