Hemopoesis

Question 1

time it takes to change from reticulocyte to mature RBC

Answer 1

1-2 days

Question 2

function of normal RBC

Answer 2

transport O2 from lungs and CO2 to the lungs,

Question 3

Structure of normal RBC

Answer 3

biconcave discs to enable maximal O2 saturation with large surface area and deformability for passage through small capillaries and splenic sinusoids.

Question 4

Anemia

Answer 4

Def: reduction below normal limits of total circulating red cell mass. determind from Hemoglobin concentration, hemtocrit/packed cell volume. classified by morphological changes and pathophysiological mechanisms. hypochromic, macro,microcytic, spherocytes

Pathogenesis:

• blood loss
• –acute hemorrhage-internal or external, concern is hypovolemia
• –chronic blood loss, rate of loss exceeds RBC regeneration, or when iron stores are depleted
• increased RBC destruction.
• decreasedRBC production.

Clinical Features- asymptomatic when mild.

Symptoms: (related to poor O2 supply to tissues)- weakness, easy fatigability, headaches, fainting, shortness of breath on exertion

Clinical signs: increased pulse, RR, SV, cardiac failure, pallor, nail changes (severe cases)

Question 5

MCV

Answer 5

Mean cell volume is the average volume of RBC, if it is low it means you have microcytic anemia, if it is high you have macrocytic anemia. femtoliters

Question 6

MCH

Answer 6

Mean cell hemoglobin(mean corpuscular hemoglobin) average content of hemoglobin per RBC- picograms)

Question 7

Mean Cell Hemoglobin concentration

Answer 7

average concentration of hemoglobin given volume of packed RBC’s (g/dL). High levels means you have hyper chromic EBV, Low levels means hypochromic

Increased:hereditary spherocytosis.

Question 8

Red Cell distribution width

Answer 8

coefficient of variation of RBC volume, if it is above average percentage that means there is a wide variety o sizes o RBCs

Question 9

Hemolytic anemias

Answer 9

Common Features- Shortened RBC life span, increase in erythropoietin, and erythropoesis, accumulation of Hb breakdown

Classified as intravascular or extravascular, or intrinisc or extrnisic to RBCs

intrinsic RBC defect:

• membrane defect- hereditary pherocytosis
• enzyme defect G6PDD, Paroxysymal nocturnal hemoglobinuria
• hemoglobin defect- sickle cell disease, thalassemias

Extrinsic defect
-immune mediated damage- autoimmune , drugs
non immune damage- mechanical trauma, infections, chemicals
-sequestration, due to hypersplenism.

LAB evidence- normochromic normocytic anemia- polychromasia (increased reticulocytes. hyperplasia with increased spherocytes, increased unconjugated bilirubin and free hemoblobin, increased LDH, decreased haptoglobin, Hemosiderinuria and hemoglobinuria.

Question 10

Intravascular hemolysis

Answer 10

due to mechanical injury of RBC’s eg defective cardiac valves or microvascular thrombi,

complement fixation of antibody coated RBCs

Infections: intracellular parasites, production of toxins.

Question 11

Extravascular hemolysis

Answer 11

RBC’s less deformable, or rendered foreign by immune system, most cases are extravascular.

Question 12

Hereditary spherocytosis(intrinsic hemolytic anemia-membrane abnormality))

Answer 12

abnormla critical proteins in RBC skeleton, caused by mutations. as the RBC’s age they become spheroid, less deformable and destroyed by spleen in 10-20 days, Auto-dom. in 75% cases.

Proteins affected- ankyrin Band 4.2(anchors spectrin on inside) Spectrin(main framework) Band 3(transmembrane protein that anchors spectrin to membrane)

Pathogenesis- reduced membrane stability leads to loss of small fragments during normal shearing stresses. the RBC’s become more spherical and can’t get through spleen.

Clinical features- most commonly mild to moderate chronic hemolytic amemia with 25% asymptomatic, and a minority severely affected from birth.) intercurrent infections like parvovirus 19 can cause aplastic or hemolytic crises.

Treatement- splenectomy(anemia corrects but spherocytosis persists.

Diagnosis- family history, evidence of hemolysis, peripheral blood findings and osmotic fragility test, MCHC is INCREASED

Question 13

osmotic Fragility test

Answer 13

add hypotonic salt solutions, this causes RBC’s to swell and lyse prematurely in 65% of HS patients.

Question 14

G6PDD

Answer 14

abnormality in the HEXOSE Monophosphate shunt(glutathione metabolism). Leaves RBC’s prone to oxidative injuries
Hereditary form is most important
G6PD A- about 10% American Blacks)- half life of enzyme activity moderately reduced
G6PD mediterranean- mostly middle eastern- half life of enzyme severly reduced.
G6PD B- most common

Pathogenesis- abnormal enzyme variants are misfolded and susceptible to proteolytic degradation. Since mature RBCs hae no nucleus they don’t form new proteins and the enzyme activity falls and older RBC’s not protected against oxidant stresses. Oxidation of SH groups in globin chains cause preciptation of denatured globins on RBC membrane (Heinz bodies). If membrane damage is severe, intravascular hemolysis occur. Less affected RBC’s get through with only a “bite” and become bite cells and spherocytes. these cells are removed by the spleen.

Etiology:
X-linked
may be due to natural selection.

Clinical featuers

• acute hemolysis- 2-3 days afeter exposure to oxidant stress like infection, drungs, foods, (fava beans.
• neonatal jandice-
• chronic low grade hemolyti anemia lacking known environmental triggers.

Question 15

Hemoglobinopathies

Answer 15

RBC diseases mostly characterized by mutations in globin genes- prodcution of defective hemoglobins- sickle cell disease, Hb C disease.

Question 16

Sickle Cell disease

Answer 16

Homozygotes have almost 100% HbS
Heterozygotes have about 40% HbS referred to as AS
10% of black americans are heterozygotes.

Etiology: point mutation or missense mutation, glutamic acid replaced by valine, in translated region of Beta globin chain (HbS)

Pathogenesis: Deoxygnated HBS molecules aggregate and polymeraize, further deO2 leads to needle sickling, which is initially refersible but after rpeat, becomes irreversible and leads to RBC stickiness

Factors affecting SCD:

• HbA HbF, alpha thalassemia all decreases sickling (alpha due to less hemoglobin.
• HbC, dehydration, lower pH, long exposre of low O2 tenstion, increase sickling.

Clinical features- intra and extravascular hemolysis, moderate to severe anemia, Hyperplastic bone marrow leading to skull bone changes. Hypersplenism in kids leading to autosplenectomy due to fibrosis. More prone to infections by encapsulated bacteria, H. Influenzae and pneumococcus. Hyperbilirubinemia, gallstones. sickle cell crisis

diagnosis- clinical findings, family history, blood smear, use O2 consuming agent like metabisulfite to dinuce sickling, most common is hemoglobin electrophoresis and prenatal diagonsis-dna screening.

Tx- analgesics, rehydration, exchange transfusions, folic acid, penicilllin prophylaxis if you don’t have a spleen, hydroxyurea to increase HbF. Bone marrow transplant.

outcome- 90% survive til 20 50% survive til 50 infection major death cause in under 5 years, organ failure due to vasoocclusive complications in adults.

Association- small vessel thrombosis.

Question 17

—-Sickle Cell Crisis—-

Answer 17

caused by infections, dehydration, cold, hypoxia, acidosis, sichemic events in bones, lungs, brain, retina, kidneys(kids young adults), leg ulcers (adults.

• –Sequestration crises: kids/young adults, rapid pooling of blood in spleen
• –Aplastic crises: acute viral infection by parvovirus 19
• –Hemolytic crises.

Question 18

Thalassemia syndromes

Answer 18

caused by genetic lesions resulting in decreased synthesis of Alpha or Beta globin chains of HbA resulting in low levels of normal Hb

hypocrhomic microcytic RBCs

excess of unimpaired chain leads to aggregates which leads to insoluble inclusions which leads to extravascuar hemolysis.

Question 19

Beta Thalassemias

Answer 19

diminished Beta globin chians with unimpaired Alpha chain production
Beta+ thalassemia- reduced Beta chains produced- mutation in promoter region of gene
Beta0= no beta chains produced- mutations in splicing or chain temination, frame shift of stop codon mutation.
HYPOCHROMATIC MICROCYTIC anemia

Pathogenesis- reduced survival of RBC’s and RBC precursors, due to cell membrane damage by preciptated alpha cahins. 75% of precursor RBC normoblasts die in hyperplastic bone marrow(inneffective erythropoiesis.
-extramedullary hematopoiesis, if severe,
excessive absortpion of dietary iron.

Clinical syndromes.

• -Beta Major B+/B+ B+/B0, B0/B0- severe transfustion dependant
• -Beta minor/trait: B+/B, B0/B: mild asymptomatic anemia
• -Beta intermedia=milder ariants of 1 severe variants of 2 or 1 combined with alpha thalassemia.

Course: growth retardation and death unless regular blood transfusions.

Treatment: iron chelators given to prevent overload and cardiac failure(important cause of death
Bone marrow transplantation is potentially curative in major, otherwise survial only to 3rd decade.

Diagnosis- Low Hb,VERY Low MCV RDW normal,

Question 20

Beta thalassemia Major

Answer 20

Mediterranean, parts o Africa, S.E. Asia and immigrants from these areas.
presents 6-9 months after birth when HbF falls, Hb levels 3-6 g/dl
HbF remains elevated and may become major Hb
HbA2 may be normal low or high.

Clinchopathological features:
Expansion of hematopoietic marrow which leads to prominent facial bones, erosion of bony cortex and new bone formation, huge spleen and liver due to EXTRAvascular hemolysis and extramedullary hematopoiessi, Hemosiderosis and secondary hemochromatosis due to iron overolad. (affects heart liver and pancreas)

Question 21

Beta Thalassemia Minor

Answer 21

Usually asymptomatic with mild HYPOCHROMIC MICROCYTIC anemia hemoblogin EPH will show increase in HbA2 and normal or increased HbF. need to recognize to avoid treating as iron deficiency anemia and to provide genetic counseling.

Question 22

Alpha Thalassemia

Answer 22

1 deleted gene- silent carrier
2 genes deleted- thalassemia trait (a/a -/-= SE Asian, a/- a/- = african) Only SE Asian can produce offspring with severe Alpha thalassemia
3 genes deleted- Hemoglobin H disease
4 genes deleted- Hydrops fatalis.

Question 23

Hemoglobin H disease

Answer 23

HbH fromed from tetramers of excess Beta chains, has high affinity for O2 leading to severe tissue hypoxia, HbH is also prone to oxidationwhich will lead to precipitaed inclusions in older RBCS and extravascular heymolysis, moderate anemia.

Question 24

Hydrops fetalis

Answer 24

Hb Barts,
tetramers of excess gamma chains,
high O2 affinity, no O2 reaches the tissues,
leads to death unless given intrauterine transfusion,
fetus is pale, edematous, and enlarged liver/spleen.

Question 25

Paroxysmal Nocturnal Hemoglobinuria (PNH)

Answer 25

Aquired clonal stem cell disorder. Associated with periodic hemolysis. Mutations in x-lnked PIGA gene

Pathgenesis: PIGA forms GPI which anchors proteins to cell surfaces. normally 3 GPI linked proteins inhibit complement activation on blood cells. Absence of CD55/59 C8 binding protein causes susceptibilty to hemolysis. many normal people harbor small clones with PIGA but don’t pesent. these clones need to gain a selective advantage. Find the mutation in all the cells but really only RBC and platelets cause problems,

clincal features: happens more at night than day because you get a littl emore acidic at night but doesn’t happen for most people. INTRAVASCULAR hemolysis: low grade, mild to moderate anemia, Thrombosis due to platelet dysfunction which causes a prothrombotic state.

Course- some will develop aplastic anemia and autoimune problems, also develop leukemia through white blood cells.

diagnosis- lab findings- hemoglobinuria, hemosiderinuria, use FLOW CYTOMETRY- Flaer test.

Associations: thrombosis leading to death,(venous), aplastic anemia, Iron deficiency, 5-10% develop acute myeloid leukemia or myelodysplastic syndrome.

Treatment: immunosuppression or bone marrow transplant.

Question 26

Immune Hemolytic anemias

Answer 26

warm antibody, cold antibody, aka cold agglutinin, and cold hemolysin IHA aka Paroxysmal cold hemoglobinuria. require a Direct antiglublin test(DAT)) or indirecte antiglobulin test (IDAT)

Question 27

DAT

Answer 27

detection of antibodies with or without complement on patient RBCS. RBCs are incubated with antibodies to these elements and a positive test will have RBC agglutination

Question 28

IDAT

Answer 28

patient serum is tested for its ability to agglutinate test RBCs that have known antibodies bound onto them. temperature difference defines warm or cold.

Question 29

Warm antibody immunohemolytic anemia

Answer 29

Most common form f IHA, 50% idiopathic, 50% predisposing disease like Lupus, lymphoma, or drug reaction. MOST ANTIBODIES ARE IgG CLASS. IgG needs heat to get the reaction going they need to have the warm temperature to move and get together.

Question 30

Cold Agglutinin hemolytic anemia

Answer 30

IgM antibodies able to bind and agglutinate RBCs at temperatures below 4C

acute sefl limited hemolysis, seen in infectious disease mycoplasma, pneumonia, infectious mononucleosis, CMV, influenz, HIB

Chronic hemolysis idiopathic or associated with low grade lymphoma.

Question 31

Cardiac valve prosthesis

Answer 31

mechanical RBC damage, artificial more than biprosthetic valves, causes microangiopathic hemolytic anema. you have lots of fragments or shictocytes and can lead to DIC, malignatn hyeprtension, SLe, TTP, HUs, disseminated ancer.

Question 32

Megaloblastic anemias

Answer 32

Vitamin B12 or folate deficiency, both are coenzymes necessar for synthesis of hymidine, deficiency = low DNA synthesis and so you will have defective nuclear maturation, with normal RNA and protein synthesis. This will cause nuclear cytoplasmic asynchrony.

PB findings: Pancytopenia
-macrocytic anemia, low reticulocyte count, enlarged hypersegmented neutrophils of 5 nuclear lobes or more.

BM findings: hypercellular hematopoesis, ineffective becasue many of them die in bone marrow. Large red cell and white cell precursors, large megakaryocytes and large immature nuclie or increased nuclear lobes.

Question 33

B12 deficiency

Answer 33

methylmalonyl coenzyme A makes succinyl coA and requires B12.

deficiency causes increased plasma and urine methyl malonic acid which is used for LAB TEST

Causes neurological deficits with degenration in the dorsal and lateral tracts of the CNS affecting the sensory and motor functions causing paraparesis, sensory ataxia, lower limb parasthesis.

etiology, decreased intake, increased requirement, but biggest is impaired gastrointestinal absorption from Pernicious anemia, malabsoprtion, and intestinal resections.

Question 34

Pernicious anemia

Answer 34

atrophic gastritis, immune destruction of gastric mucos = no B12.

Clincal features, N. Europeans, and descendant, insidious onset with severe anemia by the time of presentation

Lab diagnosis: CNS lesions of B12 deficiency may be present, megaloblastic enemia from PB and BM, low serum B12, metaplastic intestinalization of mucosa,

Schilling test inabilty to absorb oral dose of B 12, use uirine excretion of labeled B12)

reticulocyte response: improvement of anemia 5 days after parenteral B 12 injection.

Serum antibodies to IF.

Question 35

Folate Deficiency

Answer 35

Dietary green veggies, some fruits, must be raw, 50-200 mg absorbed in proximal jejunum. more likely than B12 because modest body stores

Etiology- Decreased intake- diet inadequate in green veggies, like alcoholics.

• impaired gastrointestinal absorption
• increased requirements- pregnancy, infancy, disseminated cancer, methotraxate chemo

Diagonsis
PB/BM- megaloblastic anemia
increased homocysteine, decreased serum folate-only true diagnostic test,
no neurological defects. Exclude B12 FIRST

Question 36

Iron deficiency anemia

Answer 36

commonest cause of anemia worldwide, is related to poor diet and common in infants, children, reproductive females, elderly

Etiology-dietary deficiency, rare in industrialized countries,

• impaired absorption-gastric bypass, duodenum ectomy
• increased requirements- growing kids, premenopausal female, pregnancy
• chronic GI blood loss, commonest cause of iron deficiency in western world, in adult men and postmenopausal women, can be due to a tumor.

Diagnosis

• CBC- low hb, low MCV, High RDW (differnet form thalassemia)
• Blood smear- hypochromic microcytic anemia, sever cases- poikiocytosis- pencil cells
• Biochemical indices- low iron, low transferrin saturation, high TIBC, low ferritin.
• Depletion of BM iron stores absence of stainable iron,

Question 37

Iron metabolism

Answer 37

iron from animal products- 20% absorbable, inorganic non heme iron- 1-2 %, most absorbed in duodenum , some enters blood but most remain in intestinal cells and is lost by naturlal exfoliation. iron balance regulated at the level of absorption. HEPCIDIN made in liver reponds to high levels of liver iron stores, inhibits uptake.

daily requirement- 7-10 in males 7-20 mg in females, free iron is toxic, almost all bound as ferritin, 80% of functional iron in hemoglobin and rest in myoglobin and iron containing enzymes.

Storage of rion- ferritin in liver, spleen, BM, skeletal muscle. Hemosiderin=partly degraded aggregates of ferritin

Iron transport- Plasma protein, transferrin, normal 33% saturated with iron. normal serum 100-120 micrograms per 100 mL, total Iron binding capacit (TIBC) 300-350 mg/ml

Question 38

Anemia of chronic disease

Answer 38

Most common cause of anemia in hospitalized patients

etiology:
- chornic bacterial infections- lunb abscess, endocarditits
- chornic immune disorders- rheumatoid arthritis
- Malignant tumors- cancers of lung, breast, lymphoma

Pathogenesis- impaired iron utilization and lowered RBC production
- decrease in transfer of rion from BM storage pool to RBC precursors, this is induced by hpecidin which is produced in response to inflammatory mediators,

Diagnosis.

• normochromic, normocytic anemia, sometimes hypocrhomic microcytic.
• LOW serum iron, LOW TIBC, HiGH, serum ferrtin
• normal or increased iron stores in BM
• decreased erythropoiesis with inapporpriately low erythropoietin

Question 39

Aplastic anemia

Answer 39

actually a PANCYTOPENIA from bone marrow failure due to a defect in a multipotent hematopoeietic stem cell

etiology- congenital- fanconi anemia
aquired, most common comes on out of the blue.
-65% unknown cause, could be immune mediated destruction or antigenically altered stem cells, or primary intrinsic stem cell defect, due to genetics.
-35% known cause- alkylating agents and antimetabolites- chemotherapy , could be whole body irradiation, aor virla agents like hepatitis D/TT, CMV, EBV, Herpes Zoster

Diagnosis

• PB- pancytopenia, normochromic normocytic, LOW RETICULOCYTES
• BM hypocellular only fat cells, DRY so you can’t aspirate.

Differential- need BM to rule out acute leukemia and myelodysplastic syndrome.

Course: spontaneous remission uncommon,- in children a firal etiology is more likely to have full recovery

Treatment- allogenic bone marrow transplant in young patients
-immunosupporession in older adults

Question 40

Myelophthisic anemia

Answer 40

BM replacement by abnormal infiltratest that disturb normal architecture, often with fibrosis like metastatic cancer, granulomatous inflammation–> leukoeruthroblastic blood picture. you see this with white and RBC in PB with teardrop red cells

Question 41

Diffuse liver disease

Answer 41

BM hypofunction affecting maily the RBCS etiology multifactorial

Question 42

Chronic renal disease

Answer 42

multifactorial anemia includes Low EPO

Question 43

Polycythemia

Answer 43

elevated RBC concentration and Hb levels

Relative polycythemia- due to reduced plasma volume- usually secondary to dehydration

Absolute- Primary- polycythemia Vera (PRV) a chronic myeloproliferative neoplasm
Secondary-
-appropriately high EPO levels- lung disease, cyanotic heart disease, living at high altitiude
-inappropriately high EPO levles, EPO secreting tumors

Question 44

Classification algorithm for polycythemia

Answer 44

is it relative or absolute
if absolute , is it primary or secondary
if secondary, are EPO levels appropriate or inappropriate.

Question 45

Causes of Bleeding disorders

Answer 45

small blood vessel fragility- PIPES, platelet deficiency or dysfunction-PLATELETS, coagulation abnormality- PROTEINS.
pipes and plateletes- usually superficial, coagulation is typically deep and more severe

Question 46

Abnormal platelet function

Answer 46

can be congenitial or aquired, aquired usually from Aspirin or N-SAIDS. or uremia from chronic renal failure

Question 47

Thrombocytopenia Decreased production

Answer 47

a bone marrow problem
-generalized BM disease with aplastic anemia,

Etiology- Marrow infiltartion leukemias, metastatic cancer, granulomatous inflammation, drug induced ethanol(toxic to MKC’s) cytotoxic drugs HIV (T2MKC’s) measels, Megaloblastic anemia (T2MKC’s) meylodysplastic syndromes. (neoplastic in transition to becoming a neoplasia.

Question 48

Thrombocytopenia Decreased survival

Answer 48

peripheral problem
immune destruction- antiplatelet antibodies or immune complexes
- autoimmune
–primary ITP or secondary(SLE, lymphoma
-isoimmune- post transfusion neonatal
-drug associatied= heparin, septrin(antibiotic), quinidine
-infection associated HIV, CMV infectious mononucleosis.

NON immune destruction
-DIC, TTP/HUS, Giant hamgniomas, Microangiopathic hemolytic anemias, all consume your platelets.

Question 49

Primary immune Thrombocytopenia (ITP)

Answer 49

(acute- uncommon, children, post viral with spontaneous resoluttion, transient immune thrombocytopenia, just provide supportive therapy)
Chronic- more common WOMEN 20-40, insidious onset with or without mucosal bleeding, rarely resovles spontaneously.

Symptoms- petechial hemorrhages, nose bleeds, heavy periods, increased mucosal bleedings, not enough platelets to plug bleedings that happen all the time,

Diagnosis-  decreased plateltes, 
PB- large platelets
Increased bleeding time, 
autoantibodies against platelet membrane glycoproteins
incrased megakaryocytes in BM biopsy

Treatment: immunosuppression and splenectomy to prevent spleen problems, you will have enough platelets this way to stop bleeding.

Question 50

Non immune thrombocytopenias TTP/HUS

Answer 50

Thrombotic thombocytopenic purpura: clinical syndrome of fever, thrombocytopenia, microangiopathic hemolytic anemia, transient neuro deficits and renal failure

Hemolytic uremic syndrome- clinically like TTP but no neuro or renal failure

features in common: widespread platelet thrombi in small vessells

• platelet consumption
• polatet thrombi in small vessell and mechanical microangiopathic hemolytic anemia.

Question 51

Hereditary clotting disorders

Answer 51

typically involve single clotting factor defect
Factor VIII most serious, Von willebrand disease most comon,

VIII_ cofactor for factor IX in intrinsic pathway
VWF- promotes adhesion of platelets to the subendothelial layer, after endothelial damage/ disruption

Question 52

Acquired clotting disorders

Answer 52

typically multifactor abnormalitis, like vit. K deficiency, severe liver disease, disseminated intravacular coagulation.

Question 53

Von willebrand disease

Answer 53

commonest inherited disorder, more than 20 variants
Type 1 70% of all cases, mild mostly mucosal bleeding
Type 2 35% of cases, mild to moderate bleeding
Type 3 severe deficiency , affects VIII stabilty in plasma so may present like hemophilia A

(1,3 reduced quantity of VWF, 3 is severe, 2 is qualitative functional abnormality.

Question 54

hemophilia A factor VIII deficiency

Answer 54

most common hereditary disease with serious bleeding, 30% from new mutations. has a range of clinical severity.

Clincal presentation: massive bleeds after trauma or surgery. Spontaneous hemorrhages, follwoing minimal trauma to joints and muscles

Lab Findings:Normal Platelets, Bleeding time and PT, PROLONGED PTT, factor VIII assay

Treatment: recombinant FVIII infusions , 15% develop FVIII antibodies, risk of transmission of viral diseases.

Question 55

DIC

Answer 55

acute to chronic thrombotic hemorrhagic syndrome, secondary to an underlying disease

Pathophysiologic mechanism- systemic activation of coagulation sequence formation of micro thrombi resutls in hypoxia and infarctions, this consumes platelets and clotting factors and secondary activation of fibrinolysis (results in hemorrhage

Major disorders with DIC: Obstetric: abruptio placenta, retained dead fetus, septic abortion, toxemia, amniotic fluid embolism
Infections: Gram-ve sepsis, meningococcemia
Neoplasms, disseminated cancer (pancrease, lung, prostate stomach (acute promyelocyctic leukemia.
Massive Tissue injury: Trauma, burns, major surgery
Other: Shock snakebite, acute intravascular hemolysis, heat stroke, vasculitis.

Major mechanisms for triggering DIC

• release of tissue factor or thromboplastic substances into circulation-placental tissue, leukemic granules, mucus bacterial endotoxins.
• widespread injury to endothelial cells: sepsis, immune complexes, organisms, temperature extremes.

Question 56

Lymphopenia

Answer 56

Cinical settings for lymphopenia- Advanced HIV, Drug induced(chemo, steroids), Autoimmune disease, acute viral infections.

Question 57

Neutropenia

Answer 57

pathogenesis: Reduced or ineffective production- bone marrow problem,
–suprresion of myeloid stem cells(aplastic anemia, usually idiopathic)
–suppression of committed myeloid precursors-often drug induced
– ineffective granulopoieisis (megaloblastic anemias, myelodysplastic syndrome)
–Marrow infiltration (granulomatous inflammation, tumors)
–Rare inherited disorders (Kostmann syndrome)
accelerated

consumption/destruction: peripheral problem

• -immune related (idiopathic autoimmune disease, drugs)
• -splenic sequestration (splenomegaly)
• -increased consumption (overwhelming infection

Clinical implications: agranulocytosis= severe neutropenia, prone to life threatening infections
Severe neutropenia is most commonly drug induced- chemotherapy, idiosyncratic, many drugs, usually immune mediated by suppression of marrow precursors.

clinical Picture:
Symptoms and signs related to infection, empirical treatment with broad spectrum antibiotics, , regimes include G-CSF

Question 58

Neutrophilic Leukocytosis

Answer 58

Infections- pyogenic bacteria, Sterile inflammation- tissue damage, acute inflammation, acute hemorrhage.Malignancy- extensive/necrotic tumours.

Question 59

Eosinophilic Leukocytosis

Answer 59

Allergic disorders- astham, hay fever,
skin diseases (bullous pemphigus, pemphigoid, dermatitis, herpetiformis
Parasitic infection
Drug reactions.
Malignancies (Lymphomas- Hodgkin’s, t- cell)
Collagen vascular disease, vasculitis.

Question 60

Basophilic leukocytosis

Answer 60

rarely reactive, always indicates myeloproliferative neoplasm especially CML

Question 61

Mono cytosis

Answer 61

Chronic infections (TB, rickettsiosis, bacterial endocarditits, malaria)
Collagen vascular disease (SLE)
Inflammatory bowel disease (ulcerative Colitis)

Question 62

Lymphocytosis

Answer 62

chronic immunologic sitmulation often associated with monocytosis. Viral infections, Bordetella Pertussis infection.

Question 63

Toxic granulation

Answer 63

loads of basophilic granules in neutrophils

Question 64

Toxic vacuolization

Answer 64

fat cells

Question 65

Doweh’s body

Answer 65

hazey sky blue structres near the membrane,

Question 66

band cell

Answer 66

premature neutrophil, happens in pseudoleukemia pattern

Question 67

Pancortical/interfollicuar hyperplasia

Answer 67

t-cell response

Question 68

sinus histiocytosis.

Answer 68

dilated sinusoids containing histiocytes

Question 69

DIFFICULT DIFFERENTIALS

Answer 69

reactive increase in granulocytes- leukemoid reaction vs chronic myeloid leukemia
Reactive lymphocytosis vs. chronic lymphocytic leukemias, or circulating lymphoma cells.

in lympho nodes
-reactive lymphadenitits vs. lymphoma.

Question 70

lymphadenopathy

Answer 70

In children, reactive lymphadenopathy is common- cervical, axillary, inguinal, Nodes are usually tender, otherwise asymptomatic. May be history of infection- no rush to biopsy follow up a nd look for decrease in size
Adults over 40 Reactive adenopathy is less likely and there is increased conern for malignancy (lymphoma, metastatic carcinoma) Fine needle or tissue biopsy should be performed.

Question 71

WBC neoplasias

Answer 71

pathogenesis- chromosomal translocation and oncogenes- non random chromosomal abnormalilites are frequent in WBC neoplasms.
inherited genetic factors- Down syndrome
Viruses EBV, HTLV-1, KSHV/HHV-8l

Environmental agents e.g. H.pylori, imdysregulation in HIV
Iatrogenic e.g. radiation, chemotherapy.

Leukemia- involves bone marrow at the time of presentation

Lymphoma- discreate tissue masses discrete tissue masses at the time of presentation-

acute- precursor cells predominate
chronic- differential/mature cells predominate

Question 72

Lymphoid neoplasms

Answer 72

3 types
Lymphomas- are in 60% non hodgkins’s and almost all hodgkins, they have non-tender lymph node enlargment
40% of non hodgkins’s lymphoma are extranodal with site related symptoms (skin-rash, brain, perivascular w/stroke or brain disorders, breast- lump

leukemias- symptoms and signs related to BONE MARROW REPLACEMENT- cytopenias

Plasma cell neoplasms- bone destruction/pian due to pathological fractures.

Lymphomas
Non- hodkins
-precursor B-cell, mature B- cell Precursor T/NK cell, Mature t/ NK cell
Hodgkin’s lymphomas.

Diagnosis- histo examination fo involved tissue, 90% of lymphoid neoplasms are B-cell. can see a stage of B-cell differentiation. Show clonality with same antigen receptor gene rearrangement pattern, use PCR/Southern Blot.

LAB INVESTIGATIONS B-cell show light chain restriction, either Kappa or Lambda- use flow cytometry/immunohistochemical stains.
-many have recurrent cytogenetic abnormalities, which aid in their diagnosis. `

Question 73

Non- Hodkin’s Lymphoma: Peripheral B-cell neoplasms

Answer 73

Chronic lymphocytic Leukemia/Small lymphocytic Lymphoma
B cell Prolymphocytic leukemia (B-PLL)
Lymphoplasmacytic lymphoma (LPL)
Marginal zone lymphomas (MZL)
Mantle cell lymphoma (MCL)
Follicular lymphoma (FL)
Hairy cell leukemia (HCL)
Plasma cell neoplasms
Diffuse Large B-cell lymphomas (DLBL)
Burkitt Lymphoma (BL)

Question 74

Commonest NHL’s in north america and Europe

Answer 74

90% are B cells and 10% t cells
B cell ympohmas - 35% DLBL,
25% FL, 7% SLL, 6% Malt lymphomas, 6% Mantle cell lymphomas

Question 75

Follicular Lympoma

Answer 75

Clinical Presentation-
Middle aged, 40/60, PANLESS lymphadenopathy, often generalized, presents often in stage IV with BM involvement in 85% and frequent liver and spleen involvment.

Morphology- tumor arises from Germinal center b cells-
2 patterns, nodular or mixed nodular and diffuse
2 types of cells, small cells and large cells.
diffuse pattern and greater numbers of large cells indicate aggressive behavior.

Diagnosis: FLow, IHC: CD19,20,10+ . TransL of t 14-18 in 90%

Course- except for predominance of large cells, it is indolent but incurable and 40% transform to aggressive lymphoma usually DLBL. median survival less than a year

Question 76

diffuse large B- cell lymphoma

Answer 76

Clinical presentation:
Median age 60- wide range 5% of childhood NHL
60% present in LN’s often in a SINGLE enlarging mass 40% present as extranodal mass GI tract, skin
B SYMPTOMS- fever wt. loss night sweats. this is for more aggressive lymphomas
often stage 1 or 2 for daignosis with negative BM

Morphology:
Diffuse non-nodular pattern of large cells. can be primary de novo or secondary to transformation of previeous low grade lymphoma. (esp. FL)

Out come- moderately aggressive behaviour, fatal if untreated but potentially curable- combination chemo causes 75% remission and of those 50% cured.

Question 77

SLL/CLL

Answer 77

CLL- most common adult leukemia but only 5 present inthe form of SLL

Clinical presentation- Early, incidental finding of lymphocytosis in a CBC
Later- symptoms related to cytopenias like BM replacement, autoimmune hemolytic anemia or thrombocytopenia(if you have both then it’s Evan’s syndrome). Enlarged LN, spleen or liver

Morphology: PB- mature looking lymphocytes with characterisitc smudge cells secondary to fragility
BM- interstitial nodules leading to diffuse replacement
LN diffue pattern of predominantly small round lymphocytes with a few larger cells that are often concentrated in pale proliferation cetnres,

Diagnosis- Immunophenotype- CD 19,20,5,23,43. CD 20 is dim

Course- indolent behavior, incurable, overal mean survival of 4-6 years and if diagnosed early up to 10 years. cause of death is progressive pancytopenia which leads to increased bleeding and infections. transformation to a more aggresive neoplasm with larger cells like prolymphocytic leukemia (20%) and DLBL ( 10%)

Question 78

Marginal Zone lymphoma (MALToma)

Answer 78

Indolent lymphoma mostly small mature looking lymphocytes usually happens in pathological sites. , mostly commonly extranodal at mucosal sites.
mucosal sites normally don’t have much lymphoid tissue but aquired it from chronic infection or autoimmunity. common site is the stomach superimposed on Heilcobacter gastritis, antibiotics has caused regression of MZL. other common sites are salivary and thyroid gland on top of autoimmunity like sjogren’s or hashimoto’s or graves. MZL’s remain localized for long periods before spreading and often recur or spread to other mucosal sites.

Question 79

Burkitt lymphoma

Answer 79

Aggressive B-cell neoplasm, variably associated with epstein barr virus, African-100% EBV, Sporadic -15% , HIV-25%

Morphology- diffuse infiltrate of MEDIUM sized cells with very high MITOTIC RATE and much apoptosis. many macrohpages a starry sky pattern

Clinical features-
endemic/sporadic- kids and young adults (30% of childhoodl lymphomas
extranodal masses
-endemaic: mandible, abdominal viscera(kidneys, ovaries, adrenal glands
- sporadic- usually abdominal(ileocecal

Diagnosis: immunophenotype of CD 19,20,10 surface IG, characterisitc translocation of cmyc on chrom8, and either IG heavy or light chian loci 8:14>2:8, 8:22

Differential- FL becasue of phenotype.

Course: very aggressive but good response to high dose ehcmo, most kids and young adults can be cured, older adults do worse.

Question 80

Hairy cell leukemia

Answer 80

Clinical presentation: rare, indolent Middle aged males (M:F 4:1)

Morphology: PB cells with round or kidney shaped nuclei and pale blue cytoplasm with thread like or bleb like extensions
BM- infiltrate of smlllympohcytes abundant plae cytoplasm with fried egg appearance enmeshed in reticulin. fibroses means no aspiration (dry tap) so use biopsy
Spleen- red pulp infiltration with a beefy red appearance. Liver also infolved frequently

Diagnosis: CD 20, Cd 11c, Cd 25, Cd 103+

Question 81

Plasma cell Neoplasms

Answer 81

B cell neoplasms with small plasma cell differentation whtat secrete monoclonal Ig or fragments of Ig.

Diagnosis -Blood M component (monoclonal Ig) and urine has Bence Jones proteins (monoclonal light chains kappa or lambda)

Question 82

Multiple myeloma

Answer 82

Clincal presentation:

• A plasma cell neoplasm involving multiple bones. Middle aged 50-60 years with more males than females,
• Bone pain due to bone destruction or fractures of mostly the axial skeleton (vertebrae>ribs>skull).
• Cytopenias due to marrow replacement.
• Organomegaly usually late in disease course
• bacterial infections secondary to neutropenia and HYPOGAMMGLOBULINEMIA (normal IgG low)
• renal insufficiency secondary to hypercalcemia, bence jones proteins and amyloid deposition.

Diagnositic criteria- M-protein in serum or urine( no minimum) Bone marrow clonal plasma cells or plasmacytoma(no min)
-Related organ or tissue impairment(hypercalcemia, renal insufficiency, anemia, bone lesions
Serum electrophoresis shows single bands

Treatment- chemo, bone marrow transplant.

Course: untreated die in 1 year. with chemo- 60% remission, median survival of 3 years, few younger than 50 patients are allogenic bone marrow transplant and can survive 10 years

Question 83

Hodgkin’s vs Non-Hodgkin’s

Answer 83

Hodgkin’s-
-tumor cells in minority,
-orderly spread node group to node group, to spleen to liver to BM.
-Extra nodal involvement uncommon,
-greater involvement of SINGLE axial node group.
NHL- tumor cells majority, no pattern of spread, extranodal presentation, multiple nodes involved.

Question 84

Hodgkin’s lymphoma

Answer 84

Clinical Presentation: Painless rubbery enlargement of one or more lymph nodes, pain involved in nodes after drinking alcohol

• systemic symptoms of fever, night sweats and weight loss, designated A if no symptoms and B if symptos
• cuatneous anergy(iching)

Morphology: Neoplastic Reed Sternberg cells ( altered germinal center B lymphocytes) in minority
-Non-neoplastic inflammtory cells, lymphocytes, plasma cells, eosinophils in the background in the majority.

Diagnosis:

• staging- S1 single lymph node region, S2- 2 or moe LN regions on same side of diaphragm S3 LN regions on both sides of diaphragm which could include spleen. S4- Multiple/ disseminated involvement of 1 or more extralymphatic organs and tissues.
• Who classification uses reed sternberg IPHT, Classical- IPHT- CD 15+, 30+, 45-, Variant CD20+, 45+, 15-, 30-

Treatment and prognosis:
Radiation, chemo depending on stage
Stage is most important prognostic indicator, current therapy so effective, it elminates the effect of adverse histology.

Course 5YDFS S1,2 90%, IV 60-70%, Long term survivors get secondary cancers like AML, and lung cancer.

Question 85

Nodular Sclerosis,

Answer 85

classical HL65%

Clinical presentation- commonest subtype, mostly adolescents or young adults, males same as femal with meadiastinal involvement common. stage 1 or 2 presentation susually with or without neck nodes presentation.

Morphology- Large nodules at least partly surrounded by thick fibrous collagen bands. presence of Reed sternberg Lacunar cells.

Question 86

Mixed Cellularity,

Answer 86

Classical HL25%
Diffuse nodal replacement, frequtn RS cells often EBV+ , viphasic occurance, young adutls and adults older than 55, Males more than females, Systemic symptoms, and advanced stage abdominal involvement at presentaiton.

Question 87

Lymphocyte rich

Answer 87

Classical HL, uncommon

Question 88

Lymphocyte depleted

Answer 88

Classical HL- less than 5%
Abundant RS cells that may be bizarre- EBC+ background of few lymphocytes and fibrosis. Elderly or HIV positive with systemic symptoms and advanced stage at diagnosis.(stage IV)

Question 89

Lymphocyte predominant

Answer 89

Variant HL 5%

Morphology: large nodules, bu tno collagen band fibrosis. RS cells have popcorn.cell appaearance.

Clincal presentation: under 35 years, M>F, indolent, tendency to recur. 5% transform to DLBL

Question 90

Acute Lymphoblastic leukemia/lympohma (ALL)

Answer 90

Clinical presentation:85% of all ALL are precursor B-cell types most presenting as childhood acute leukemias.

• 15% of ALL are precursor T-cell usually present as mediastinal(thymic) mass in an adolescent male.
• onset abrupt and severe
• symptoms related to BM replacement- cytopenias, bone pain, generalized enlargement of LN’s liver, spleen, thymic enlargement (T-ALL) testicular enlargment (B-ALL), CNS involvement (B-ALL) with headaches, blurred vision vomiting.

Diagnosis-Subclassification into B and T-cell relies on IPHT

Treatment:Chemo- with testicular and CNS prophylaxis.
BMT for relapsed cases.

course:90% remission and 65% cured,
Good prognostic factors age:2-10 years good, WBC count in PB, low good, >100000 bad, IPHT- Pre B-cell good, all other bad, Cytogenetics. Hiperdiploidy good (12:21) other ploidy bad 9:22

Question 91

Distinguishing ALL from AML

Answer 91

Morphology: granules or Auer rods in AMl
stains- myeloperoxidase, sudan black esterases in AML, PAS in ALL
IPHT- flow or IHC,
cytogenetics: 90% are abnormal hyperdiploidy, translocations

Question 92

Acute myeloid leukemia

Answer 92

Etiology

• Chromosomal translocation
• -younger adults with de novo AML, 15:17, 8:21, 16:16,
• -Deletion/monosomy of chromosome 5 and 7 in older adults with AML with myelodysplasia or post chemo/radiotherapy

Pathogenesis:

• translocations disrupt genes encoding transcription factors for normal differnetiation. Chimeric genes cause abnormal fusion of proteins that leads to a block in terminal differentation
• additional steps like mutated TK with persistent aberrant activation lead to increased cellular proliferation
• accumulation of proliferating neoplastic precursors in the BM suppresses normal hematopoieitic progenitors.

Clinical presentation.

• mostly affecting adults, peaking after 60
• acute onset weeks to months and symptoms or signs related to cytopenias. Bone pain, organ involvement, or enlargement(liver, spleen, lymph node, brain), but is much less common than in ALL
• tissue (skin/mucosal/soft tissue) infiltrates can be a feature of AMLS with MONOCYTIC differentiation.
• anemia- fatigue,
• neutropenia- fever, sepsis.
• thrombocytopenia- spontaneous mucosal skin, intracranial bleeds
• extramedullary masses- uncommon
• DIC (15:17)

Diagnosis: WHO classification

• AML with recurrent chormosomal rearrangements,
• AML with multilineage dysplasia
• AML, Therapy related
• AML, not otherwise specified(are those in former FAB classifcation except those with recurrent chromosomal rearrangemetns. - Acute promyelocyitc leukemia, M3, and AML with some maturation, or Acute Myelomonocytic leukemia.

PB: circulating blasts cells, with usually increased WBC but may be normal or low. occasionally no circulating blasts (aleukemic leukemia)
BM 20% blasts in BM,
Flow- expression of myeloid and blast cell surface markers
-cytogenetics.

therapy/prognosis (t:15:17)- chimeric protein RARalpha PML blocks differentiation beyond promeylocytes, stage after blast cells. treat with vit A derivative alltransretinoic acid ATRA, which induces differentiation to neutrophils. this will help put it into remission but relapse occured unless treated with chemo. most give combination therapy. (60% remission but over half relapse within 5 years. :
-8:21 and inv16-better
-15:17 -intermediate
del 5, 7 poor
BM Transplant for high risk AML or relapsed AML but often recurs.

Question 93

Myeloid neoplasms

Answer 93

arise from myeloid cells. of the bone marrow, by transformation of a progenitor cell.
Primary involvemnt of bone marrow often also peripheral blood and sometimes secondary hematopoeitc organs. (liver spleen , nodes)

Question 94

Myelodysplastic syndromes

Answer 94

Definition: clonal maturational defects in stem cells leads to ineffective hematopoesis which leads to cytopenias
Clinical settings PRIMARY MDS>50 gradual onset, therapy related MDS 2-8 years post post chemo/radiorx
Outcome- transfomration of AML 10-40% cases or death related to complcations of cytopenias to median survavl of 9-30 months (only 2-4 months for therapy related MDS)

MorphologyPB: macrocytic anemia, cytopenias with or wtihout blasts
BM- usually hypercellular but ineffective heamtopoeisis, morphologic abnormalities in RBC and or granulocytic precursors, and or megakaryocytes. With severe MDS, blast cells are increased by by definition less than 20% of total cells.

diagnosis: cytopenia, refractory anemia (persistent unexplained macrocytic anemia with or without neutropenia and thrombocytopenia. PB and BM morphology, abnormal 5/7 trisomy 8

Treatment: allo-BMT in younger patients, supportive rx in older patients.

Question 95

Chronic myeloproliferative neoplasms

Answer 95

disorders of pluripotent progentitor cell, capable of uncontrolled proliferation with full differentation, Neoplastic cells and theri off spring fill BM and suppress normal hematopoeisis, tumor cells circulate and home to secondary heamtopoeitc livers causing organomeglay termination in a spent phase of progressive BM fibrosis and cytopenias (PV, ET, MF) or transformation to acute leukemia (CML)

Pathogenesis,
arise from multipotent progentior cells, capable of uncontrolled proliferation with full differentiation
common feature- mutated constantly activated tyrosine kinases circumvent normal growth controls, result is growth factor independent proliferation and survival of marrow precursors. there i sno impairment of differentiation.

Chronic myeloid leukemia- 9:22 phildelphia and BCR-ABl fusion gene- ABL kinase activation
Polycythemia vera- JAK2 kinase activation
Essential thrombocythemia- JAK2 and MPL mutations, constant kinase activations
primary meylofibrosis- Jak 2 and MPL point mutations. same

Clinicopathological features- neoplastic cells and their offspring fill BM and suppress normal hematopoiesis. tumor cells circulate and home to secondary hematopoetic organs. Termination in transformation to acute leukemia (CML) or a spent phase of progressive BM fibrosis and cytopenias (PCV, ET, PMF>

Question 96

chronic myleloid leukemia

Answer 96

defect in pluripotent stem cell for meyloid and lymphoid lineages, but morphologic expression is mainly granulocytic characterized by uncontrolled proliferation with full differentaton.

clinical presentaiton
Adult male 25-65 years, gradual onset of tiredness, weakness, loss of weight and appetite, abdominal discomfort due to enlarging of the spleen.

Diagnosis PB- leukocytosis of immature cells (left shift) mostly neutrophils, metamyelocytes, and meylocytes, also eosinophils and basophils(t destroy, does not prevent blast criss,
BM: Nearly 100% cellular, mostly ↑ granulocytic precursors(but percentage of blast cells not ↑). Also ↑
megakaryocytes.

interferon alpha, slows down disease, hydroxyurea, gentle chemo allogenic bone marrow transplant in younger pateints (75% cure)

Course, outcome:

• Stable phase lasts median 3 years (2-5), without effective treatment.
• Accelerated phase: After 2-5 years, 50% of stable phase progress in increasing blasts, bone marrow fibrosis, thrombocytopenia, extra cytogenetic abnormalities
• Blast crisis: Acute leukemia (75% myeloid, 25% lymphoid) within one year.