heme exam A

What parameters are measured directly on the automated cell counter?

WBC count, RBC count, Hgb concentration

What parameters are measured by electrical impedance?

WBC and RBC count

electrical impedance

Changing electrical resistance as blood cells pass through a tiny apparatuses to count and size them

What parameters are calculated?

MCH, MCHC, Hct, Absolute differential count

3 sites where bone marrow aspirate can be obtained

Posterior iliac crest, anterior iliac crest, tibia (children)

Difference between bone marrow aspirate and bone marrow from peripheral blood

Bone marrow aspirate has marrow spicules (particles)

When do you reject a bone marrow sample

If the aspirate has no spicyles, it’s a dry tap, there’s contamination, there’s clotting

Blood viscosity is assessed by

hct

The linearity of an analyzer has exceeded, what should be done

Dilute the sample then rerun, then calculate the result by the dilution factor

IgM is detected in the sample, what does it cause and how is it resolved

it causes false decreased RBCs and false elevated MCV &MCHC - incubate and warm sample at 37C for 15-30 minutes then rerun

Plt clumping can cause what? And how is it resolved

False decreased plt count, request a redraw (can use EDTA again but to prevent EDTA induced clumping opt for sodium citrate tube (blue top) instead)

Liberia in the sample causes what? How is it resolved?

It falsely elevates MCHC and Hgb- so clear the plasma with saline treatment

Interpret histograms of white cells

RBC histogram

What is the correct specimen tube for hemogram?

EDTA (lavender/purple top)

If an EDTA tube cannot be used when running a hemogram, what should be used?

Sodium citrate (light blue)

flow cytometry: forward scatter

Light scattered at 0-10 degree angle

Detects size

Flow cytometry: side scatter

Light is scattered at a 90 degree angle Detects

Detects granularity

Molecular hemoglobin types difference between infants, adults, and children

Infants carry up to 80% fetal hemoglobin, which binds tighter to oxygen

Children and adults carry adult hemoglobin (HbA), designed to release oxygen more easily to active tizzues

What criteria makes a specimen unacceptable for CBC analysis?

presence of clots, gross hemolysis, underfilled tubes, short draw, dilution with IV fluids, incorrect collection tubes

what cell is this?

10–14 µm; 3–5 nuclear lobes; pink-tan cytoplasm with fine, violet-pink granules

Neutrophils

12–20 µm (largest WBC); indented or horseshoe-shaped nucleus with lacy chromatin; abundant gray-blue cytoplasm often containing vacuoles. What cell is this?

monocyte

Which cell is known for having water-soluble cytoplasmic granules?

Basophils

12–15 µm; condensed bilobed nucleus; cytoplasm packed with large, uniform, bright reddish-orange granules

Eosinophils

10–14 µm; indented or lobulated nucleus (often obscured); crowded with large, dark purple-black granules that are water soluble. what cell is this?

Basophils

lymphocytes

mediates adaptive immunity

T cells and NK cells (cell-mediated)

B cells (antibody production)

Which cell is most associated with Immediate hypersensitivity reactions?

eosinophils are associated with immediate (type I) hypersensitivity

Type IV (delayed type hypersensitivity is mediated by what cells?

T cells only

B cells are responsible for what hypersensitivity reactions?

Type I, II (Cytotoxic), and III (immune complex mediated)

Peripheral blood cells graph (RR and function)

What is the ESR?

The erythrocyte sedimentation rate measures how fast RBCs settle to the bottom of a test tube to detect active inflammation in the body

This is due to proteins clumping RBCs together, so they sink faster= higher ESR= inflammation

It monitors conditions such as RA, lupus

High vs low reticulocyte count

High: bone marrow working harder to replace RBCs (seen in hemolysis and bleeding)

Low: bone marrow not producing enough retics (iron deficiency or bone marrow failure)

The CBC values most useful in predicting peripheral blood picture is? and how are they interpreted?

MCV, RDW,MCH, MCHC, WBC, and Plt volume= they are all measured through an automated analyzer

M:E ratio definition and normal range

NR: 2.1-4.1

Myeloid to Erythroid ratio

Nonspecific esterases (NSEs_ traget?

monocytic lineage

Specific esterases target?

Granulocytic lineage (negative in monocytic leukemias)

What is the TRAP stain associated with?

Hairy cell leukemia (B-lymphocytes with spiny projections)

would have a positive TRAP test is bright red staining

AML is a positive disease state in what cytochemical stains?

MPO, Sudan black (SBB), Specific esterase (CAE)

ALL (acute lymphoblastic leukemia presents with?)

how is it treated with Gleevec?

>20% lymphoblasts, hypercellular marrow

hepatosplenogmegaly

Gleevec (Imatinib) is used specifically for Philadelphia chromosome positive ALL to inhibit BCR-ABL tyrosine kinase

Gleevec (Imatinib) is used specifically for for

Philadelphia chromosome positive ALL to inhibit BCR-ABL tyrosine kinase

Velcade and Aredia are both used to treat what disease?

Multiple myeloma

ATRA (All Trans Retinoic Acid) is used to treat

Acute Promyelocytic Leukemia (APM/M3 subtype) to force immature promyelocytes to mature to neutrophils so DIC risks can be mitigated

Explain the principle of the osmotic fragility test and correlate it an increased or a decreased osmotic fragility result with the appropriate clinical conditions.

The osmotic fragility test (OFT) measures how easily red blood cells (RBCs) burst when placed in salt solutions with lower salt levels than normal blood

Increased OF: RBC break down faster and at higher than normal salt concentrations; seen in hereditary spherocytosis

Decreased OF: thalassemias and iron deficiency anemia associated, have thin or flatter than usual cells

possible sources of error of the erythrocyte sedimentation rate (ESR).

tilted tube: angled tube accelerates settling and causes false elevated results

incorrect blood to anticoagulant ratio or air bubbles

improper mixing and testing delays (like high temps can falsely elevate ESR)

ESR normal range

15-30 ml per hour

Increased vs decreased ESR clinical significance?

An elevated erythrocyte sedimentation rate (ESR) indicates inflammation in the body

a decreased ESR points to conditions that slow down red blood cell settling, such as polycythemia or extreme changes in cell shape

Troubleshooting Wright’s Stain

too blue: too much staining time, poor washing, too alkaline buffer/stain (need to lower pH of it)

too pink Wright’s stain causes

too little staining time, reduce washing, raise pH to neutral bc the stain is too acidic

Adjusting blood smear thickness

decrease to thin the smear

increase the angle to make the smear thicker

When making a peripheral blood smear for neonates, what do you do?

Neonates have more viscous blood, so decrease the spreader angle (25 to 30 instead of 45 degree)

Describe the condition of PCH; include its etiology, pathophysiology (including specific antibody produced), and characteristic lab results

autoimmune hemolytic anemia where exposure to cold temperatures triggers an immune mediated destruction of RBCs

caused by biphasic immunoglobulin G Ab; the Donath-Landsteiner 9D-L) Ab specifically, a polyclonal IgG directed against the P blood group Ag on RBCs