CLS Lecture: Hematology #1
Define the terms MCV, MCH, MCHC, and RDW. Demonstrate how to calculate each given the hemoglobin, hematocrit, and RBC count.
1. MCV = mean corpuscular volume (Hct x 10)/RBC 2. MCH = mean cell hemoglobin (Hgb x 10)/RBC 3. MCHC = mean corpuscular hemoglobin content (Hgb/Hct) x 100 4. RDW = red cell distribution width; look at chart and PBS
List the test parameters that comprise a complete blood count (CBC).
CBC i. aka Hemogram + Differential ii. primary screening test provides info on cellular components of blood in circulation iii. hemogram - counts, concentration, population size iv. differential - automated or manual - categorization of WBC subsets v. peripheral blood smear review included at discretion of institution
Identify the breakdown products of hemoglobin and recoup how the body conserves and recycles essential components.
i. normal RBC destruction is by senescence; phagocytized in spleen ii. hgb broken down = heme, iron, glob in - heme ---> amino acid pool, and excreted in urine & feces - iron ---> stored as ferritin or hemosiderin, or as circulating transferrin - globin ---> plasma protein and amino acid pool
Define anemia.
inability of circulating blood to adequately oxygenate tissues for proper metabolic functioning
Define hematopoiesis.
continuous regulated process of blood cell production including: - cell renewal - proliferation - differentiation - maturation
Define cytokines, discuss their characteristics and roles in the differentiation and maturation of hematopoietic progenitor cells.
glycoproteins that regulate proliferation, differentiation, and maturation of hematopoietic precursors - exhibit multiple biological activities (regulation of autoimmune and inflammatory reactions, and hematopoiesis) - interact synergistically with other cytokines - have amplification potential - effective at low concentrations main specific proteins: - EPO (erythropoietin) produced by kidney, much lesser amount in liver - TPO (thrombopoietin) produced mainly in liver
List and describe the theory and techniques of primary lab tests used in the classification of anemia.
i. hemoglobin (cyanmethemoglobin method) - hemolysis reagent - oxidization reagent - cyanisation reagent - laser @ 540nm ---> colorimetric analysis ii. hematocrit iii. RBC indices - MCV, MCH, MCHC, RDW iv. PBS - cell populations - relationships in quantity - size and shape of RBCs - RBC inclusions - RBC inclusions - presence of immature forms - follow-up tests: special staining of hgb, RNA, DNA, granules, denatured or remnants of RBCs v. retic count - absolute count - percentage - corrected = (patient HCT x Retic %)/mean value of reference HCT (45) - RPI (retic production index) = (Pt hct/0.45) x (retic %/2.0) - immature retic fraction (IRF) vi. chemistry tests - iron tests: ferritin, serum iron, TIBC or/and UIBC, % saturation, hemosiderin - bilirubin - haptoglobin - folate and B12 - methemoglobin - porphyrins and porphyrin precursors
Describe a WBC differential count, and the difference between an automated and manual count.
manual = looking at slide and counting 100 cells and tracking the different types using a counter (i.e. 60 neutrophils, 25 lymphocytes, etc.) automated = counts 10,000 WBCs
Describe the general morphologic changes that occur during RBC maturation; include size, morphologic characteristics, and approximate distribution in BM.
*rubri = erythro - rubriblast = proerythroblast/pronormo - prorubricyte = basophilic erythroblast - rubricyte = polychromatophillic erythroblast - metarubricyte = orthochromatophillic erythroblast - reticulocyte = polychromatophillic erythrocyte - mature erythrocyte - 30% of BM is red BM - 70% of BM is yellow BM
Platelets/thrombocytes*
- 2-3 um in diameter - round to oval in shape
Define myoglobin and state it's function.
- heme protein found in skeletal and cardiac muscle - main fxn is to transport oxygen from the muscle cell membrane to the mitochondria - serves as an extra reserve of oxygen to help exercising muscle maintain activity longer - used to diagnose acute myocardial infarction (AMI)
Reactive lymphocytes
- normal cells that have altered as a result of a normal response to stimulus - high in viral infections - extremely variable in size and morphologic features (generally: chromatin is coarsely clumped, nucleus is extremely variable in shape, sometimes increased cytoplasm, cytoplasm stains deep blue/purple)
List causes of anemia.
- nutritional deficiencies - blood loss - increased destruction of RBCs - decreased production of RBCs - infections - toxicity - hereditary or acquired defects
For the functional classification of anemias, state three defects used in categorizing. List anemias caused by functional abnormalities.
- proliferation, maturation, and survival - look at figure 11-4*
Name anatomic sites involved in hematopoiesis, and the physiologic function of each.
1. Bone marrow (medullary) i. major site of blood cell production; 6 months to adult ii. one of the largest organs of the body iii. network of 3-D honeycomb matrix iv. advanced system of vessels regulates flow of particles v. Marrow - Red - active, developing blood cells - Yellow - inactive; fat cells, undiff. mesenchymal and macrophages - contains cells: endothelial, macrophages, lymphs, osteoblasts, osteoclasts, fibroblasts - contains substances: fibronectin, collagen, proteoglycans, etc. 2. Liver (extramedullary, detox) i. major site of blood cell production during 2nd trimester ii. protein synthesis and degradation iii. coagulation factor synthesis iv. carbohydrate and lipid metabolism v. drug and toxin clearance vi. iron recycling and storage vii. hemoglobin degradation viii. when BM can't produce enough cells, liver will make RBCs ---> extramedullary hematopoiesis 3. Spleen (extramedullary) i. largest lymphoid organ ii. indiscriminate filter of circulation - culling = damaged, degraded cells are phagocytized - pitting = macrophages remove inclusions or damaged surface membranes iii. recycles red cells iv. storage site for platelets (30% of total) v. immune defense against bacterial infections vi. splenectomy ---> HJ bodies present, or damaged red cells 4. Lymph nodes (extramedullary) i. lymphatic organs, parallel circulatory system ii. lymph - fluid part of blood, traverse connective tissues, has low protein concentration, no RBCs iii. functions - immune defense against pathogens - lymphocyte proliferation - initiate specific immune response to foreign antigens (germinal center) - filter particular matter, debris, bacteria in lymph 5. Thymus (extramedullary) i. in utero, until birth - stores primitive lymph cells and macrophages, also mesenchymal, reticular, epithelial, dendritic ii. adults - progenitor cells from BM travel to the thymus to mature (obtain CD4 and CD8 surface antigens)
Describe the evolution and formation of blood cells from embryo to fetus to adult stage.
1. Mesoblastic (19 days) - Yolk sac ---> AGM (aorta-gonad-mesonephros) - intravascular sites (in vessels) - produces embryonic Hb (Gowers, Portland) 2. Hepatic (5-7 weeks) - major site is liver - also spleen, kidney, thymus, lymph nodes - clusters of recognizable cells, blasts - Hb: predominatently Hb F, start of Hb A 3. Medullary, adult (Late 4th month) - medullary = inner part of bone - at 6 months, BM takes over as primary site - all cell types involved: in BM, also lymph nodes, spleen, liver, thymus - lymphoid tissues: primarily BM and thymus, also spleen, lymph nodes and other lymph tissues
Describe the composition of blood.
1. Plasma = liquid portion, 55% - water, minerals, nutrients, metabolic waste, hormones, antibodies, enzymes, and proteins (including clotting factors) - Ca2+, Na+, K+, Cl-, Mg+, H+ - main protein is albumin, for osmotic pressure and transport 2. RBCs = 45% 3. WBCs & platelets = ~1% *normal adult has 6L and is 7-8% of total body weight
Describe how to make a manual blood smear (peripheral blood smear, PBS).
1. need a blood drop from an anticoagulant tube, i.e. EDTA (can use cap piercer) 2. place drop of blood on first slide close to frosted end 3. use second slide non-frosted edge to slowly move across first slide until you make contact with the drop of blood ---> then quickly push back across 4. want a "thicker slide"? ---> hold push slide at a higher angle (good for low Hgb)
State how a diagnosis of anemia is made.
1. patient history 2. physical exam; signs/symptoms 3. lab findings: hematological & others - HGB, HCT, RBC indices - PBS - retic count - BM smear and biopsy - other tests
"Other" Heme Reference values
Immature reticulocyte fraction (IRF): 0.09-0.31 RDW: 12-14.6 Plt count: 150-400 x 10^9/L MPV: 6.8-10.2 fL CSF: RBCs = 0; WBCs = <5/mcL
RBC Reference values
Male Hb g/dL: 14-17.4 (CRITICAL; 6.6 or 19.9) Hct %: 42-52 (CRTICAL; 18% or 66%) RBC x 10^6/mcL (uL): 4.5-5.5 Female: Hb g/dL: 12-16 (CRITICAL; 6.6 or 19.9) Hct %: 36-46 (CRTICAL; 18% or 66%) RBC x 10^6/mcL (uL): 4.0-5.0 Both: MCV fL: 80-100 MCH pg: 28-34 MCHC: 32-36 Reticulocytes %: 0.5-2.0
Describe what is measured for each test parameter, and list the reference/normal values for each.
Male Hb g/dL: 14-17.4 (CRITICAL; 6.6 or 19.9) Hct %: 42-52 (CRTICAL; 18% or 66%) RBC x 10^6/mcL (uL): 4.5-5.5 Female: Hb g/dL: 12-16 (CRITICAL; 6.6 or 19.9) Hct %: 36-46 (CRTICAL; 18% or 66%) RBC x 10^6/mcL (uL): 4.0-5.0 Both: MCV fL: 80-100 MCH pg: 28-34 MCHC: 32-36 Reticulocytes %: 0.5-2.0 ----------------------------------------------------- Total leukocyte count (x10^9/L): 4.5-11.0 (higher in babies) Segmented neutrophil %: 40-80 (much lower in babies) Absolute (x10^9/L): 1.8-7.0 Band neutrohpil %: 0-5 (much higher in birth) Absolute (x10^9/L): 0-0.7 Lymphocyte %: 25-35 (much higher in babies) Absolute (x10^9/L): 1.0-4.8 Monocyte %: 2-10 Absolute (x10^9/L): 0.1-0.8 Eosinophil %: 0-5 Absolute (x10^9/L): 0.0-0.4 Basophil %: 0-1 Absolute (x10^9/L): 0.0-0.2 ----------------------------------------------------- Immature reticulocyte fraction (IRF): 0.09-0.31 RDW: 12-14.6 Plt count: 150-400 x 10^9/L MPV: 6.8-10.2 fL CSF: RBCs = 0; WBCs = <5/mcL
Monocyte/Macrophage morphology and functions
Monocyte - only in PB - 3-8% of WBCs - recruited to sites of inflammation Macrophage - peritoneal, alveolar, splenic, Kupffer/liver - Reticuloendothelial system: fixed and wandering macrophages throughout body (major locations are liver and lung) ---> functions: antibacterial resistance, tumor resistance, defense against shock, antigen processing, lipid metabolism, protein turnover, iron metabolism
Explain the function of each type of granulocyte and monocyte found in the peripheral blood.
Neutrophils - avid phagocytes at site of infection Eosinophils - increases rapidly during allergies and parasitic infection Basophils - rarest of WBCs that contain large histamine-containing granules (seen in high # in CML cases) Lymphocytes - important role in the immune response; 2 types are B cells and T cells Monocytes - largest of all WBCs that become macrophages a. Macrophages - phagocytosis, bacterial killing, antigen presentation
Compare the reference intervals for hemoglobin, hematocrit, RBCs, WBCs; in infants, children, and adults.***
Newborn Hgb: 13.4 - 20.0 gm/dL
WBC Count and Diff Reference values (Adult)
Total leukocyte count (x10^9/L): 4.5-11.0 (higher in babies) Segmented neutrophil %: 40-80 (much lower in babies) Absolute (x10^9/L): 1.8-7.0 Band neutrohpil %: 0-5 (much higher in birth) Absolute (x10^9/L): 0-0.7 Lymphocyte %: 25-35 (much higher in babies) Absolute (x10^9/L): 1.0-4.8 Monocyte %: 2-10 Absolute (x10^9/L): 0.1-0.8 Eosinophil %: 0-5 Absolute (x10^9/L): 0.0-0.4 Basophil %: 0-1 Absolute (x10^9/L): 0.0-0.2
Anisocytosis vs Poikilocytosis
a. Anisocytosis - abnormalities in size i. macrocytosis (increased MCV): - true macrocytosis (vitamin B12 and folate deficiency, erythrocyte maturing factors) - pseudo-macrocytosis (regenerative response of BM in case of blood loss) ii. microcytosis (decreased MCV): - iron deficiency or failure in absorption or utilization of iron (deficiency of vitamin C and B6) ----------------------------------------------------- b. Poikolycytosis - abnormalities in shape i. acanthocytes - seen in: liver disease*, post splenectomy, anorexia nervosa, starvation ii. ovalocytes/elliptocytes - seen in: hereditary, thalassemia, iron deficiency anemia, sickle cell anemia iii. target cells/codocytes - seen in: anemias*, hyposplenism, IDA, thalassemia, jaundice, liver disease, hemoglobinopathies iv. sickle cells/drepanocytes - seen in: genetics, hemolytic anemia, sickle cell disease v. spherocytes - seen in: hereditary, auto-immune hemolytic anemia, direct physical or chemical injury, >37% MCHC ---> common in babies* vi. schistocytes - seen in: DIC* (watch for low platelet count or non-fxn platelets), glomerular disease, thalassemia, hemangiosarcoma, splenic disease, IDA, direct thermal injury, megaloblastic anemia vii. stomatocytes - seen in: regenerative anemias, liver disease, lead poisoning - can appear as an artifact (due to drying) viii. teardrop cells/dacrocytes - seen in: idiopathic myelofibrosis, megaloblastic anemia, thalassemia, pernicious anemia, congenital or acquired dyserythropoiesis ix. echinocytes/crenated RBCs/Burr cells - commonly occurs as an artifact during smear prep - seen in: premature infant, uremia, peptic ulcer, gastric carcinoma, pyruvic kinase deficiency x. helmet cells/bite cells - due to splenic pitting and impalement of RBC on fibrin strands - seen in: microangiopathic hemolytic anemia, DIC
Describe the chemical composition of the red cell membrane in terms of percentage of lipids, proteins. Describe the importance of erythrocyte deformability and permeability.
a. Composition i. 45% lipids and glycolipids ii. 55% proteins and glycoproteins b. Structure i. phospholipid bilayer ii. skeleton structure aids in strength and flexibility (squeeze through vessels) iii. permeable to: water and anions; impermeable to: cations - osmolarity
Describe hemoglobin function in terms of the oxygen dissociation curve, including the terms "shift to the left" and "shift to the right", pH, temperature, 2,3-DPG and PO2.
a. Definition - affinity of hemoglobin for oxygen is related to the partial pressure of oxygen (PO2) - P50 value: defined as the amount of oxygen needed to saturate 50% of hemoglobin - also affected by blood pH and 2-3 BPG (biphosphoglycerate; from glycolysis, affects acid-base balance in body) b. Shifts i. "shift to the left" - oxygen held on to more/longer - decreased H+ (INCREASED pH) - decreased CO2 - decreased temperature - decreased 2-3 BPG - decreased PO2 ii. "shift to the right" - oxygen held on to less/shorter - increased H+ (DECREASED pH) - increased CO2 - increased temperature - increased 2-3 BPG - increased PO2 altitude = shift to the left exercise = shift to the right
Describe the forms of iron, how the body absorbs and transports iron, its physiological role, and the importance of ferritin, hemosiderin, hepcidin, and transport proteins.
a. Forms of iron i. Ferrous (Fe2+) - absorbed form ii. Ferric (Fe3+) - transport and storage form - delivered to cells having receptor sites: gut mucosal cells, liver cells, reticuloendothelial system cells b. Absorption i. ~10% absorbed in duodenum and jejunem ii. absorption is tightly regulated iii. absorption controls total body iron content iv. once absorbed, there is no mechanism to excrete excess iron v. two types: heme (meats, especially organs) and non-heme (spinach, beats, beans, almonds, bran flakes) ---> dietary intake is 10-20 mg/day c. Transportation i. absorbed iron is transported in the blood bound to transferrin ii. ~1% of total body iron is bound to transferrin iii. transferrin carries & releases iron to bone marrow ---> hemoglobin d. Function i. oxygen transport and storage: essential for heme, myoglobin, and hemoglobin ii. component of some enzymes involved in cellular oxidative mechanisms iii. cell growth and proliferation ----------------------------------------------------- e. Ferritin, Hemosiderin, Hepcidin, Transport proteins i. Ferritin - major form of storage iron - soluble molecule - protein shell surrounding iron core - stored as ferric iron - serum levels parallel storage levels -- i.e. used to determine storage iron - BM, liver, spleen: 10-20% stored ii. Hemosiderin - second storage form of iron, less readily available - partially deproteinized ferritin - not water soluble (not measured in blood) - found in cells of liver, spleen, and BM, but in macrophages - can seen as aggregates and granules in tissue with Prussian blue stain iii.. Hepcidin - master regulating hormone of iron metabolism - synthesized in liver - has inverse relationship to erythropoiesis - modulated by: iron stores, erythropoiesis, hypoxia, inflammation/infection - good lab test, not yet developed iv. Transport proteins - Apotransferrin: protein in the plasma that moves iron from one organ to another - Transferrin: amount = TIBC (total iron binding capacity); glycoprotein formed in liver; picks up free ferric iron from GI tract and delivers it to specific receptor sites
Describe the steps of heme and globin synthesis, and where in the body production takes place.
a. Heme synthesis - heme = protoporphyrin IX ring that carries a central ferrous iron (Fe2+) - major sites: bone marrow and liver - stages of pronormoblast ---> polychromatophil - look at figure* b. Globin synthesis - occur on polyribosomes in the cytoplasm of developing erythroblasts - globin production dependent on gestational and postnatal age
Discuss disorders of iron, hemoglobin, and porphyrins.
a. Lab evaluation of iron metabolism i. Hgb, Hematocrit, Red cell count + indices ii. transferrin (carry) iii. ferritin (storage) iv. iron panel - total serum iron - TIBC (normal = 1/3 of iron bound to transferrin) - percent iron saturation/transferrin saturation b. Lead poisoning i. in the blood, 94% transferred to RBC-bound hgb ii. at half-life, lead is distributed to soft tissues (i.e. kidneys, liver, brain) ---> final storage in soft tissue (5%) and bone (95%) iii. half-life in whole blood = 2-3 weeks iv. interferes with porphyrin synthesis - ALA dehydratase ---> incr ALA (urine) - enzyme ferrochelatase ---> incr iron and protoporphyrin (blood) v. causes anemia, impaired mental development, and peripheral neuropathy vi. measured in whole blood (found in circulating RBC) and urine (76% excreted in urine) c. Abnormal Hgbs i. Methemoglobin, Sulfhemoglobin, Carboxyhemoglobin ii. Glycosylated Hgb (Hgb A1c) - level to determine diabetes - glucose in blood for long period of time ---> binds to Hgb d. Porphyria - the porphyrins closer to heme synthesis = skin issues - the porphyrins farther away from heme synthesis = neurological issues
For the morphologic classification of anemias, state the relationship to red blood indices and retic count, and describe the appearance of the PBS in various anemias.
a. MCV ---> <80 = micro-, 80-100 = normo-, >100 = macro-cytic b. MCHC ---> <32 = hypo-, 32-36 = normo-, >36 = hyper-chromic c. RDW ---> 11-14.6%... >14.6% = anisocytotic d. Retic count ---> >2 RPI = BM working harder = survival defect; <2 RPI = BM not functioning properly = nuclear maturation defect
Compare methods used in categorizing anemia -- morphologic vs. functional.
a. Morphologic i. macrocytic, normochromic - e.g. hemolytic, nuclear maturation defects (B12, folate), non-megaloblastic (alcoholism) ii. normocytic, normochromic (most common) - e.g. hypoproliferative, survival defects iii. microcytic, hypochromic (defective hemoglobin synthesis) - e.g. iron-deficiency, thalassemia b. Functional - proliferation: decreased proliferation, maturation, release - maturation: disruption of nuclear or cytoplasmic development - survival: premature loss of circulating erythrocytes look at figures 11-3, 11-4*
List criteria used in evaluating patient history, physical exam/signs, lab findings. List appropriate reflex tests.
a. Patient history i. dietary habits ii. medications (including herbal supplements) iii. exposure to chemicals & toxins iv. symptoms and duration v. previous abnormal blood tests vi. family history of abnormal blood tests b. Physical exam/signs i. general - pallor - hypotension - heart abnormality - organomegaly - hemostatic weakness ii. specific - koilonychia ---> iron deficiency - smooth tongue ---> megalobalstic (B12, folate test) - jaundice ---> hemolytic - bone deformities ---> hemoglobinopathies (electrophoresis test) - neurological ---> pernicious c. Lab findings - usually low hgb and hematocrit or RBC count - moderate: hgb 7-10 gm/dL - severe: hgb <7 gm/dL - occasional: normal H&H with physical symptoms (e.g. altitude, smoker, low blood volume) d. Reflex tests i. secondary tests
Distinguish between normal and abnormal RBC morphology: RBC inclusions, abnormal distribution, abnormal hemoglobin content
a. RBC inclusions i. Howell-Jolly bodies - nuclear remnants, small round bodies of DNA, usually single - seen in: post-splenectomy, hemolytic anemia, pernicious anemia ii. Pappenheimer bodies - composed of hemosiderin; iron inclusions - seen in: sideroblastic erythropoiesis, myelodysplastic syndrome, hemolytic anemia, splenectomy iii. Basophilic stippling - irregular basophilic granules in RBCs - deep blue in Wright's stain - fine stippling seen in polychromatophilia and increased red cells production - seen in: lead & heavy metal poisoning, unstable Hb, infection, liver disease iv. Heinz bodies - seen in Supravital stains, not Romanowsky stain - purple, blue, large, single or multiple inclusions - denatured hemoglobin - seen in: post-splenctomy, G6PD deficiency, toxins, unstable Hb ----------------------------------------------------- b. Abnormal distribution i. agglutinated RBCs - high MCHC - seen in cold antibody syndrome (antigen-antibody reaction) ---> warm specimen ---> MCHC not corrected? ---> true cold Ab - seen in: paroxysmal cold hemoglobinuria (PCH) ii. rouleaux - look in thin smear for true rouleaux (not artifact) - seen in: patients with high or abnormal types of globulins, such as multiple myeloma & Waldenstrom's macroglobulinemia, or after receiving dextran as plasma expander ----------------------------------------------------- c. Abnormal hemoglobin content i. hypochromia - MCHC <32% - seen in: IDA, thalassemia, hemoglobinopathies, sideroblastic anemia ii. hyperchromia - MCHC >36% - seen in: macrocytes present, abnormally rounded cells (i.e. spherocytes) iii. polychromasia/polychromatophilia - use supravital stains - premature release from BM - blue-gray coloration due to RNA presence - reticulocyte count should reflect polychromasia present - usually sign of BM stress
Differentiate between absolute and relative values.
a. Relative value - the percentages reported in an automated or manual diff count; relative values will always add up to 100% b. Absolute value - the actual # of each cell type in the total WBC count reported as 10^3/uL; absolute value will always add up to total WBC count
Define and label the structural components of normal hemoglobin and the primary function of hemoglobin.
a. Structure - a globular protein that consists of 4 globin chains - each with a heme moiety attached - makes up 95% of cytoplasmic content of RBCs - molecular weight = ~64 kdaltons - RBC membranes protects Hb from: denaturation and loss in kidneys - free Hb has a short half-life b. Function - oxygen transport: O2 to organs and tissues, CO2 to lungs - contributes to acid-base balance
Explain porphyrin synthesis, the incorporation of the iron molecule, and control mechanisms.
a. Synthesis i. building blocks for heme ii. BM and liver are the main sites iii. occurs in mitochondria and cytoplasm of cell b. Incorporation of iron i. cyclic compounds called tetra pyrroles ii. linked by four pyrrole rings bonded by methane bridges iii. able to bind metals due to nitrogen atoms c. Control i. enzyme ALA synthase; found in liver ii. negative feedback mechanism iii. rate of heme synthesis is flexible and can change rapidly in response to external stimuli
Describe the rationale used in initiating treatment options for anemia conditions, list lab findings that indicate effective response to treatment of anemia.
a. Treat based off the cause of the anemia! - differentiate primary vs. secondary - presentation does not always correlate w/ cause - often best to exhaust testing for "cause" before initiating supporting therapy, as it may mask underlying problem - remember: efficient production of RBCs relies on many factors b. Effective response to treatment - retic count decrease or increase / returns to normal value (RPI = 2)
State options used in the auto-verification of results.
a. definition - results falling within expected ranges that also meet institutional criteria area auto verified and may transmit directly without intervention or final confirmation by a licensed lab professional b. CLS role i. LISs produce alerts of results exceeding auto verification ranges ii. report (verify/confirm) results exceeding auto verification ranges iii. recommend subsequent testing
Discuss the porphyria diseases; their causes, physical symptoms, and lab tests used to differentiate them.
a. definition: disorder of porphyrin metabolism; enzyme deficiencies resulting in overproduction of heme precursors in BM or liver i. inherited ii. acquired - lead, alcohol, other toxins, iron deficiency, renal or liver malfunctions iii. classification based on: - specific enzyme deficiency - hepatic vs erythropoietic - cutaneous vs neurologic - inherited or acquired b. symptoms i. port wine colored urine ii. cutaneous photosensitivity iii. itchy skin (photodermitidis) iv. hyperpigmentation v. inflammatory rxn occurs on exposure to UV light vi. neurologic abnormalities c. AIP vs. PCT; look at figure* i. AIP = acute intermittent porphyria - deficiency in porphobilinogen (PBG) deaminase - PBG, uroporphyrin, and 5-ALA accumulates in plasma and urine ii. PCT = porphyria cutanea tarda - deficiency in uroporphyrinogen decarboxylase (UROD) - uroporphyrinogen exreted in urine d. Lab tests i. screening tests - urinary PBG - urinary aminolevulinic acid (ALA) - urinary porphyrins ii. quanitative assays - URO - PROTO - COPRO iii. sample collection ---> blood and/or urine, protect from light
Define hemolysis, and differentiate intravascular and extravascular red cell destruction.
a. definition: premature destruction (before 120 days) of erythrocytes b. intravascular - within the circulation - i.e. physical damage (like burns), toxicity, infections, autoimmune response to bad transfusion c. extravascular - in tissues of spleen, liver, BM by phagocytes d. intrinsic vs. extrinsic - intrinsic to RBC = inherited; extravascular site of hemolysis - extrinsic to RBC = acquired; intravascular or extravascular sites see tables 11-11, 11-12*
Describe how to evaluate and read a peripheral blood smear macroscopically and microscopically using various microscope objectives and settings.
a. macroscopically i. want the blood smear to have a feathered edge b. microscopically i. want to view near the zone of morphology (area before the tail end) ii. significant agglutination + rouleaux = probably in too thick of an area
Differentiate distinguishing morphology for stages of developing blood granulocytes.
a1. Lymphoblast - small blast, no granules, high N:C, prominent nucleoli, dense chromatin a2. Myeloblast - large nucleus, few azurophilic granules, lower N:C, nucleoli, fine chromatin b. Promyelocyte - largest in myeloid series (12-25 um), nucleoli, blue cytoplasm, reddish purple (azurophilic) granules, oval nucleus (slightly indented) c. Myelocyte - 12-18 um, round/oval nucleus, no nucleoli, 2:1 N:C, blue-pink cytoplasm, primary and secondary granules (Basophilic = dark blue, Neutrophilic = violet, Eosinophilic = orange-red) d. Metamyelocyte - 10-18 um, indented/kidney-shaped nucleus, compact chromatin at both poles, 1:2 N:C, cytoplasm and granules similar to myelocyte but with less granules e. Band cells - last immature stage for NEUTROPHILS, sometimes seen in circulation (particularly in states of chronic infection)
Explain mechanisms that regulate and modulate granulopoiesis.*
based off stem cells; i.e. healthy BM vs. cancer patient
Compare and contrast the composition and effect of oxygen binding of the dyshemoglobins: methemoglobin, sulfhemoglobin, and carboxyhemoglobin.
dysfunctional hemoglobins that are unable to transport oxygen normally - accumulation ---> toxicity - most often required: post-exposure to certain drugs or environmental conditions, sometimes hereditary (i.e. metHb) - detections: max absorption at various wavelengths 1. Methemoglobin - iron of the hemoglobin molecule is oxidized to the ferric state (Fe3+) which can't bind oxygen - ~3% normal value, <10% asymptomatic, >30% cyanotic, >50% coma/death - identify: chocolate brown blood, absorption peak @ 630nm - treatment: methylene blue (reduces Fe3+ to Fe2+) - hereditary = enzyme mutation of metHb reductase path or abnormal globin - acquired = post exposure, toxic methemoglobinuria 2. Sulfhemoglobin - formed by irreversible oxidation of hemoglobin by drugs or environmental exposure ---> sulfur atom added to pyrrole ring, 1/100 oxygen affinity - ~2% normal value, ~4% cyanotic - identify: green pigment blood, absorption peak @ 620nm - treatment: remove offensive agent (i.e. UTI sulfur drugs) 3. Carboxyhemoglobin - oxygen molecules bound to heme have been replaced by carbon monoxide (CO), 200x greater affinity than oxygen - ~2% normal value, 20-30% toxic, 40% coma/death - identify: blood/skin cherry red, absorption @ 540nm - treatment: give 100% oxygen - exogenous = automobile exhaust, tobacco smoke, industrial pollutants
Define extramedullary hematopoiesis and the anatomic sites where this may occur.
occurs in liver (primarily during 2nd trimester), spleen, lymph nodes, thymus *when BM can't produce enough cells, liver will make RBCs
Name the 6 types of polypeptide (globin) chains produced by humans.
six different globin chains: alpha, beta, gamma, delta, epsilon, zeta
