Hematology Flashcards
Hematology
-the study of blood and blood-forming elements
Blood: facts
-4-6 liters
-approx. 7-8 % of your body weight
Red blood cells: facts
-approx. 97 % of the formed elements in blood
-erythrocytes: RBCs
Hematology and its branches
-flow cytometry
-coagulation
-urinalysis
-body fluids
-CBC plus differential
Flow cytometry
-used to analyze individual cells for the presence of antigens
-Count cells with a particular immunophenotype
-This is a specialized lab
coagulation
-Think of hemostasis on a scale, if it is tipped in one direction bleeding occurs. If it is tipped in the other direction, thrombosis occurs
-Normal hemostasis is both rapid and localized
urinalysis
-is used to detect and manage a wide range of disorders, such as urinary tract infections, kidney disease, and diabetes
body fluids
-can indicate localized infections or systemic conditions depending on cellular quantities and distributions
CBC and Differential
-complete blood count/differential
-the most common hematology test
-a panel consisting of WBC, RBC, Hgb, HCT, MCH, MCHC, MCV, RDW, PLT, Retic, and Differential
What test do you run using a lavender tube?
-flow cytometry
-CBC/D
- body fluids
-contains EDTA
What test do you run using a light blue tube?
-coagulation
-contains sodium citrate
What test do you run in a syringe?
body fluids
What test do you run in a sterile cup?
-urinalysis
-body fluids
Circulating blood is divided into
45% cells (RBC, WBC, platelets)
55% plasma
Hematopoiesis
-blood cell production, hematopoiesis begins in embryonic development, progresses to the fetal liver, and later occurs in the red bone marrow
-CD34+ pluripotent stem cells give rise to the earliest myeloid and lymphoid precursors
Hemoglobulin molecules
-heme mostly consists of one protoporphyrin ring (4 pyrrole rings are joined to each other with a single iron atom)
-a complete hemoglobulin molecule contains 4 heme groups
-an adult hemoglobin (A) consists of four heme groups and four globulin chains-two alpha chains and two beta chains
Hemoglobin S
-Sickle cell trait will have hemoglobin S and A
-When Glu in an amino acid sequence is substituted with val it becomes a hemoglobin A
-Hemoglobin S is not soluble while A is soluble
Mean corpuscular volume
MCV (fL) = Hct *10/ RBC
-where MCV is the mean corpuscular volume, Hct is the hematocrit, and RBC is red blood cell count
-The reference range is 80-96 fL
Mean corpuscular hemoglobin
MCH (pg) = Hb *10/ RBC
-where Hb is hemoglobin
-reference range is 27-33 pg
Mean corpuscular concentration
MCHC (g/dL) = MCH/MCV *100
-The reference range is 33-36 g/dL
Red cell distribution width
-is a measurement of the degree of anisocytosis present, or the degree of variability in RBC size, in a blood specimen
RDW % = Standard deviation of MCV/ Mean MCV *100
-reference range is 11%-15%
Anisocytosis
-any significant variation in size
-corresponds to an RDW > 14.5 increased
-can be found in leukemia, anemias, dysplasias
normal erythrocytes
-biconcave disc
-MCV: 80-100 dL
-MCH: 28-34 pg
-MCHC: 32-36%
-Lifespan: 120 days
- 7-8 um
Macrocytes
-Larger than normal RBCs (MCV>100)
-associated with B12 or folate deficiencies
Microcytes
-smaller than normal RBCs (MCV <80)
-associated with iron deficiency, thalassemia, and lead poisoning
Hypochromic
-central pallor > 2/3rd of the cell
-less than normal amount of Hgb (MCHC <32)
-associated with iron deficiency
Hyperchromic
-RBCs with decreased or absent central pallor (slightly elevated MCHC)
- associated with hemolytic anemias, burns
polychromasia (reticulocytes)
-premature RBC that contain residual RNA
-blue-gray in color
poikilocytosis
-general term used to describe variation in RBC shape
target cells (codocytes)
-associated with hemoglobinopathies, thalassemias, IDA, and liver disease
spherocytes
-decreased surface: volume ratio resulting in no central pallor
-associated with hereditary spherocytosis, autoimmune hemolytic anemia, severe burns
stomatocytes
-can be an artificial or artifact of chemical reagents, commonly an artifact of albumin
-associated with hereditary stomatocytosis (rare)
ovalocytes
-egg-shaped, vary in Hgb content
- often in conjunction with macrocytes (macroovalocytes)
-associated with myelodysplastic syndromes (MDS). B12, or folate deficiencies
elliptocytes
-lack of central pallor
-associated with hereditary elliptocytosis, iron deficiency, and idiopathic myelofibrosis
Burr Cells (Echinocytes)
-many small undulations evenly space around the RBC surface
-often an artifact of contamination
-associated with uremia, peptic ulcers, heparin therapy, liver disease
Acanthocytes (spur cells)
-often hyperchromic
-few (3-5) blunt spicules of uneven length
-associated with congenital abetalipoproteinemia or acquired with severe hepatic disease
teardrop (dacrocytes)
-associated with idiopathic myelofibrosis can be seen in thalassemia, iron deficiency, and in any disorder with RBC inclusions
Schistocytes (fragments/ bite cells)
-results of trauma to the RBC membrane
Sickle cells (drepanoncytes)
-triggered by low O2 tension
-Pt can be homozygous or heterozygous for Hgb S
-Dense elliptocytes are often in conjunction with SS
Nucleated RBCs (NRBCs)
-immature RBC that has not yet ejected the nucleus
-normal finding for bone marrow, abnormal in peripheral blood
-indicates extreme RBC regeneration or myeloproliferative disorder
Howell-Jolly Bodies
-DNA remnants
-can be associated with absent or non-functioning spleen
Basophilic stipling
-RNA and mitochondrial remnants
-can be found in any condition with defective or accelerated heme synthesis: alcoholism, thalassemias, megaloblastic anemias, and lead poisoning
Pappenheimer bodies (Siderotic granules)
-composed of non-heme iron, resulting from excess iron in the body
-small irregular inclusions along the periphery of RBCs and usually appear in clusters
-Wright stain - pappenheimer bodies
Prussian blue stain - siderotic granules
Heinz bodies
-denatured or precipitated Hgb
-cannot be seen on wrights stain (only via crystal violet or brilliant cresyl blue)
-associated with thalassemia, G6PD, or RBC injury due to chemicals
Cabot rings
-rare
-may be found in megaloblastic anemias, erythropoiesis and homozygous thalassemia
RBC inclusions
-Hemoglobin CC crystals (bars of gold)
-Hemoglobin SC crystals (SC Crystals)
Protozoan inclusions
-malaria
-babesia
water artifacts
-non-pathological
-slide was not completely dry when staining
albuminized slides (artifacts)
-stomatocytes
-Never do RBC morphology on an albuminized slide
stain precipitation (artifacts)
-appears as dark granules on top of and next to RBCs
-can mimic bacteria
Anemia
-not a specific disease, but a condition in which there is a decrease in the competence of blood to carry oxygen to tissues, thereby causing tissue hypoxia.
-in clinical medicine refers to a decrease in the normal concentration of hemoglobin and or erythrocytes
Anemia symptoms
-fatigue, shortness of breath, faintness, heart palpitation, headache
-severity depends on the hemoglobin concentration
laboratory diagnostic criteria for anemia include
-decreased HGB
-decreased HCT
-decreased RBC
-erythrocyte indices used in morphological classification of anemia
reticulocyte count
indicates the degree of effective bone marrow erythropoietic activity and is one of the most useful lab tests in monitoring anemia in response to therapy
How can anemia be classified?
-according to either the appearance of the RBCs (morphologic classification) or the physiologic cause of anemia (etiology or pathogenic)
Microcytic hypochromic
-associated with defective Hgb synthesis. Serum Iron studies and Hgb electrophoresis are usually adequate tests
