Hem Onc Flashcards
2 derivatives of HSCs?
- Myeloids
2. Lymphoids
What do RBCs derive from?
Myeloid line of HSCs
Do RBCs have nucleus?
No
What does Wright giemsa stain for?
- Ribosomal RNA in cytoplasm of reticulocytes
- As have just lost nucleus, have lots of this
Movement of CO2 into RBC?
- Moves into cell and converted to bicarb
2. Moves out in exchange for Cl
What is anisocytosis? Poikilocytosis?
Anisocytosis: Varying sizes of RBCs
- Think, aniso sounds like “anysize”
Poikilocytosis: varying shapes
Size of RBC relative to lymphocytes?
About same size
What is a thrombocyte?
AKA platelet
What is megakaryocyte?
Progenitor cell of platelet that is of myeloid lineage
Lifespan of platelet?
8 - 10 days: this is why you have to wait this long for platelet to fully regain function post aspirin use as it is binding COX in platelet
Where are 1/3 of body’s platelets found?
Spleen: this is why you can have low platelet count if you have splenomegaly
*Reverse is true if you have no spleen
2 granules in platelets and what is contained in them?
- Dense: ADP, Ca
2. Alpha: vWF, fibrinogen
What does clopidogrel block?
ADP receptor on platelet
What does GP1B receptor on platelet bind?
VwF
What does GP2b/3a bind?
Fibrinogen
Another name for leukocytes?
WBCs
2 classes of leukocytes?
- Granulocytes: myeloid lineage derived from myeloblasts
2. Monocytes: same lineage as above
Which are the granulocytes?
- Neuts
- Basophils
- Eosinophils
What is a band neutrophil?
Immature neut with one large nucleus as it has not yet had chance to break up into bilobed nucleus
When are neuts hypersegmented?
B12 deficiency anemia
*Neuts with > 6 lobes
What is released to activate macs?
INF-gamma from T helper cells
What is TNF alpha?
- Released from macs to encourage granuloma formation
What is cell marker for macrophage?
CD14
What is CD 14 the cell marker for?
Macrophage
Protein specific to eosinophils?
Major basic protein
States in which eosinophilia is seen?
"NAACP" Neoplasia Allergy Asthma Chronic adrenal insufficiency Parasites
Difference between histo of basophils and eos?
Basophils have granules that obscure the nucleus
What do basophils release?
- Heparin
- Leukotrienes
- Histamine
- Vasoactive amines
What do mast cells mediate? How?
Allergic reactions
- Allergen binds IgE
- Mast cell binds FC portion IgE
- Upon enough IgE binding, IgE cross links and cells degranulate
What do mast cells release?
- Histamine
- Heparin
- Eosinophil chemotactic factors
What type of hypersensitivity do mast cells regulate?
Allergic:
- Asthma
- Hay fever
Medicine blocking mast cell degranulation?
Cromolyn sodium
What are dendritic cells derived from?
The monocyte, just like the macrophage
Which are the APCs?
- Dendritic - best
- Macs
- B cells
What is main inducer of primary / humoral immunity?
Dendritic cells
What are the derivatives of lymphoid lineage?
- NK - only innate cell of lymphoid origin
- B cells
- T cells
What do NK cells do?
Recognize infected cells that do not have MHC attached or Ig attached
- Induce apoptosis in these cells
What are the B cell markers?
- CD19
2. CD20
What are CD 19/20 cell markers for?
B cells
What do CD8s mainly regulate?
Viral infx
What does chromatin in clockface distribution indicate?
Plasma cells
Do eosinophils or mast cells act in asthma?
Eosinophils
When are where are RBCs made in fetus?
"Young liver synthesizes blood" Yolk sac: 3 - 8 Liver: 6 - birth Spleen: 10 - 28 Bone marrow: 18 - life
What is a type II hypersensitivity?
Rxn against antigen that is on a cell surface as would be seen in a blood transfusion
Difference between anti AB and RH antibodies?
RH: IgG Crosses Placenta
AB: IgM Does NOT cross placenta
- If you are blood type O, you naturally have anti A/B antibodies: same goes for A/B blood type
- With RH, regardless of if you are +/- you only develop the antibody if you have been exposed to the antigen
Are proteins positively or negatively charged?
Negative, as such RBCs move towards cathode in electrophoresis
Which unit is mutation in in sickle cell?
Beta globin, Alpha globin chains are normal
Mnemonic for where HgB types fall on electrophoresis?
"A Fat Santa Claus" HgA Fetal Sickle HgC disease
What is job of intrinsic and extrinsic pathway?
Extrinsic: initiation of clot
Intrinsic: Amplification of clot
Starting point of extrinsic pathway?
Factor VII: activated by Tissue Factor (thromboplastin)
What is first step in common pathway?
Factor X
What are intrinsic and extrinsic paths measured with?
Intrinsic: PT/INR
Extrinsic: PTT
What sets off factor XII in intrinsic path?
- Platelets
- HMWK
- Collagen
- Basement membrane
Steps in intrinsic path?
XII
XI
IX
VIII - ***VIII is cofactor for IX
What is required for both intrinsic / extrinsic paths to function that must be added before testing?
Ca
What is cofactor for X in common pathway?
Factor Va
Another name for factor II?
Thrombin - activated by X/V complex
What does thrombin do?
Break fibrinogen into fibrin which can now bind GP2a/3b on platelets causing them to stick
What does factor XIII do?
Activated by thrombin to stabilize thrombin meshwork
What is kallikrein? What does it do?
- Activated by factor XII
1. Enhances inflammation by converting HMWK to bradykinin
2. Converts plasminogen to plasmin: plasmin activates C3 turning on complement - **TPA is better at this
Functions of bradykinin?
Increased:
- Pain
- Permeability
- Dilation
What does antithrombin act on?
- X
2. IIa
How does heparin work?
Potentiates antithrombin
What are the hemophilias and which is more common?
A: VIII deficiency - more common
B: IX deficiency
Which factors produced by liver?
II, VII, IX, X
- Activated in vitamin K dependant process
- VIII: made in endothelial cells
What is vitamin K necessary for?
Synthesis of: II, VII, IX, X, C, S
Enzyme activating Vitamin K and drug that blocks this action?
Vitamin K epoxide reductase: warfarin blocks this action
Warfarin Heparin effect monitored by what?
Warfarin: extrinsic
Heparin: intrinsic
Why do babies get vitamin K shot?
- Important source of vitamin K is enteric flora and babies lack this so they need shot
What do proteins C/S do?
Cleave and inactivate factor V/VIII
What is factor V leiden?
Having factor V molecules that are resistant to cleavage of factor C and thus you are hypercoagulable
What to think if young person with DVT and no risk factors?
Factor V leiden
***Especially if person is white
What is secondary hemostasis?
The process of the coagulation paths with the goals of activating thrombin so that it can convert fibrinogen to fibrin
2 important factors of VwF?
- Bind platelet to collagen
2. Protect factor VIII
What does TXA2 do?
- Increases aggregation
2. Constricts to slow down blood
What leads to expression of GP2b/3a receptor?
Binding of ADP to platelets
Role of COX in platelets?
Generaties TXA2 from arachidonic acid in cell walls
What is bernard Soulier?
Deficiency in GP1b receptor
- Platelet can no longer ADHERE to collagen in damaged endothelium
When disease has mechanism similar do bernard Soulier?
VwF disease
What is ristocetin?
- Induces binding of VwF to GP1b
- If ristocetin test is negative, you are either lacking VwF or its receptor
What does negative agglutination test indicate?
- VwF disease
- Ristocetin should induce VwF binding so if test is negative you are missing VwF
What is glanzmann’s thrombasthenia?
Deficiency of GP2b/3a
First thing that occurs when endothelial layer of vessel is damaged?
Vessel constricts mediated by:
- Endothelin
- Neural stimulation
Where is VwF coming form?
- Platelets
2. Endothelial cells - majority
What is weibel palade body?
Found in vessel endothelial cell holds:
- VwF
- P selectin
What is P selectin?
Found in weibel palade body serving as speed bump in atherosclerosis
Signs of issues in primary hemostasis?
Mucosal and skin bleeding
What are mucosal and skin bleeding indicative of?
Disorder in primary hemostasis
Main risk in sever thrombocytopenia?
Intracranial bleeding
Petechiae sign of qualitative or quantitative issue with platelets?
Quantity
What is increased bleeding time indicative of?
Platelet issues
What is ITP?
- Autoimmune disease w/ IgG against platelet antigens: usually IIa/IIIb
- IgG is produced by spleen and macs in spleen will eat the bound platelets
- ***Since IgG can cross placenta
Difference in ITP in kids and adults?
Kids: acute, self resolving after viral
Adults:
PT/PTT in ITP?
Normal, this is a platelet issue, coagulation cascade has not been touched
Last ditch therapy for ITP?
Remove spleen as this is both source of IgG and platelet destruction
What is microangiopathic hemolytic anemia?
- Pathologic formation of microthrombi in small vessels
- RBCs lysed as they traverse = schistocytes
- Thrombi formation drops platelet levels
2 disorders in which microangiopathic hemolytic anemia is seen?
- TTP
2. HUS
What is TTP?
“Thrombotic thrombocytopenic purpura”
- Caused by decreased in ADAMTS13 increasing VwF multimers
- Leads to abnormal platelet adhesion and microthrombi
- Can be genetic or autoimmune
What does decreased ADAMTS13 cause and why?
TTP
- Normally degrades VwF multimers
- Since low in disease, multimers aggregate and activate paltelets
What is HUS?
“Hemolytic uremic syndrome”
Platelet microthrombi caused by endothelial damage from:
1. Drug
2. E-coli 0157
Main location of disease process in TTP and HUS?
- HUS: kidney
2. TTP: brain
What is blood smear with large platelets and and mild thrombocytopenia indicative of?
Bernard Soulier: BS is for “big suckers”
Enlarged: immature
Low levels: Don’t live as long without GP
Uremia impact on platelets?
Messes up both adhesion and aggregation
What is required for activation of clotting factors?
- Ca
- Phospholipid surface: surface of platelets
- activating substance
Signs of problems with secondary hemostasis?
Deep bleeds:
- Rebleeds after surgery
- Muscle bleeds
- Joint bleeds
What activates factor XII, VII?
XII: Subendothelial collagen
VII: Tissue thromboplastin
Disease similar to hemophilia A?
“Coagulation factor inhibitor”
- Usually vs factor VIII
- Will appear same with increase PTT however factor VIII levels are normal
What is the mixing study?
Distinguishes hemophilia A from coag inhibitor:
- Mix patient with normal plasma
1. If Hemophilia A: normal VIII in sample corrects and coagulation occurs
2. If inhibitor: donor serum will not correct
What is failed mixing study indicative of?
Coagulation factor inhibitor
Lab results in VwF diseased?
- Increased bleeding time: primary disease
- Increased PTT: remember that VwF also protects factor VIII from degradation and VIII
- Abnormal ristocetin: ristocetin usually induces VwF function
Treatment for VwF disease?
Desmopressin: increase VwF release from weibel palade bodies
What is desmopressin used to treat?
VwF disease
Another name for warfarin?
Coumadin
What is HIT?
“Heparin induced thrombocytopenia”
- Hep binds to platelet factor IV on surface
- Ptn develops antibodies to this = platelet destruction
- Platelet fragments can lead to thrombosis
What is DIC?
- Pathologic activation of coag cascade
- Forms microthrombi
- Consumes platelets and clotting factors
When is bleeding from IV sites seen?
DIC
How do obstetric complications cause DIC?
- Amniotic fluid contains Tissue thromboplastin with activates factor VII
When are Auer rods seen?
Acute promyelocytic anemia
Lab findings in DIC?
- Increased bleeding time
- Decreased PT/PTT
- Decreased fibrinogen
- Increased D dimer
3 actions of plasmin?
- Cleaves fibrin
- Cleaves fibrinogen
- Blocks aggregation
- Destroys clotting factors
What inactivates plasmin?
A-2-antiplasmin
Risk of radical prostectomy?
- Release of urokinase which activates plasmin
Effect on cirrhosis on plasmin?
- Decreased A-2-antiplasmin leading to over activation of plasmin
Lab findings in disease of fibrinolysis?
- Elevated PT/PTT: plasmin cleaves coags
- Increased bleeding time: plasmin inhibits aggregation
- Increased fibrinogen split products WITHOUT D dimer: D dimer is from fibrin and not clots are actually present
What does aminocaproic acid do?
Treats diseases of fibrinolysis as blocks activation of plasminogen
What does PGI2 do?
- Block platelet aggregation
- Released by endothelium
What is heparin like molecule?
- Released from endothelial activating antithrombin III
- Inactivates thrombin
What is thrombomodulin?
- Anticoag released by endothelium
- Takes thrombin and causes it to activate protein C instead of thrombin
- C then inactivates V and VIII
How do we get elevated homocysteine and what is the risk?
Causes endothelial damage = thrombosis
- B12/folate deficiency
- CBS deficiency “cystathionine beta synthase”
How does B12/folate deficiency lead to elevated homocysteine?
- Can no longer convert homocysteine to methionine
Interaction of B12/folate?
- Folate enters body as THF and is methylated
- To work in DNA gives methyl to B12
- B12 then gives methyl to homocysteine making it methionine = elevated homocysteine
Presentation and cause of homocystinuria?
Deficiency in CBS
- Thrombosis
- Lens dislocation
- Long, slender fingers
- Mental retardation
What is following indicative of:
- Thrombosis
- Lens dislocation
- Long, slender fingers
- Mental retardation
Homocystinuria
Function of factor C and S?
Inactive Factor V and VIII
- THink that if you double the S = 8, and if you put the Cs on top of each other you kind of have a 5
Associated risk with C/S deficiency?
- Warfarin skin necrosis
* Also remember that this is just a hypercoagulable state in general as C/S normally inactivate 5/8
What happens in Factor V leiden?
Factor V can no longer be inactivated by C/S
What is PTT not rising with standard Hep dose seen in?
Antithrombin III deficiency
How does heparin work?
Activates antithrombin III
Presentation of fat embolism?
- Petechiael rash on chest
2. Dyspnea
What causes gas embolism and presentation?
Gas embolism:
- Dyspnea
- Bone pain - infarct of bone if chronic
- Muscle pain
What is squamous cells and keratin debris in lung indicative of?
Amniotic embolism
Does inner or outer rectum drain to inguinals?
Outer
What do superficial inguinals drain? Exceptions?
- Cutaneous from umbilicus down
- External genitals
- Anus below dentate
Exceptions (deep inguinal): - Glans penis
- Posterior calf
Where does upper rectum drain lymph?
Inferior mesenteric
Does sickle cell trait present?
No
Benefit of sickle cell trait?
Protection from plasmodium falciparum
Function of BRCA1/2?
DSDNA breaks
Why does blood transfusion cause hypocalcemia?
- Contains citrate which is an anticoag and also chelates Ca
* Ca is required for coagulation pathway so this makes sense
Where does VDJ rearrangement occur?
Bone marrow
Where does isotype switching occur?
Germinal centers
What does isotype switching allow for?
Isotype: changing of IgM to other Igs
What does G6PD do in RBCs?
- Maintains NADPH levels
- Low NADPH = cannot keep glutathione reduced
- Cells at higher risk for damage
When is 14:18 translocation seen?
Follicular lymphoma = BCL 2 overexpression, a protooncogene
Brain tumor that likes cerebellum?
- Pilocytic astrocytoma: cystic with nodule on cyst
- Medulloblastoma “meduloBLUEstoma”
- Small and thick
Cancer Downs is at risk for?
ALL
When is reddish urine that darkens in light seen?
Acute intermittent porphyria
What does topoisomerase one / two do?
1: single stranded nicks to relieve supercoil
2: double stranded nicks
What is enoxaparin?
LMW heparin
What do the oxabans do?
Inhibit factor X: look anti X is in the name
Mechanism of aspirin?
Irreversibly inhibits COXI and II
What does red pulp of spleen do?
Filters:
- Old and abnormal RBCs
- Circulating bacteria
What is elevated HBA2 indicated of?
Betathalesemia
Mutation in CML?
BCR/ABL 9/22
***Causes constitutive kinase activity
How do some cancer cell become chemoresistant?
ATP dependent efflux pumps
What does P53 do?
Cuase mutated cells to arrest in G1/S
Presentation of vincristine toxicty?
Numbness and parasthesias
When is 15:17 mutation seen?
AML: mutation in retinoic acid receptor
What is wiskott aldrich?
- Eczema
- Thrombocytopenia
- Recurrent infx
What is the following indicative of:
- Thrombocytopenia
- Eczema
- Recurrent infx
Wiskott aldrich
Problem in spherocytosis?
Problem in RBC cytoskeletal abnormalities
- Usually defects in spectrin or ankyrin
Treatment of spherocytosis?
Splenectomy
What happens in positive and negative selection?
T cells
Positive: bind self antigen = survive
Negative: bind self antigen = death
What happens to hemoglobin and hematocrit during pregnancy?
- Total body volume greatly increases in pregnancy
- Since HgB and hematocrit are [] dependant, these measures will drop
- However, total RBC mass is the same and hasn’t changed
Diagnosis and microcytic / macro anemia?
Micro: MCV 100
What is broad problem in microcytic anemia?
- For some reason there is decreased HbB causing erythroblasts to undergo extra division when making RBCs
- **They are trying to keep [HgB] per RBC same so divide to make cell smaller to cope with lower HgB in body
What is responsible for giving the RBC its color?
HgB
What is heme composed of? Globin?
Heme: 1. Fe 2. Protoporphyrin Globin: 1. AAs
Causes of microcytic anemia
- Low Fe
- Anemia chronic disease: Fe stuck in macs
- Sideroblastic anemia: low protoporphyrin
- Thalassemia: decreased globin
Disease with decreased globin?
Globin: Thalassemia
Protoporphyrin: Sideroblastic
What are heme and nonheme Fe?
Heme: from meat, > absorption
Non heme: plant
Where is Fe absorbed?
Duodenum "Iron First Bro" Iron Folate B12
How is Fe absorbed from Gut?
- Enterocyte takes up Fe from gut and uses ferroportin to send it into blood if needed
What is ferroportin?
“When you look at the ‘portin’ use that to remember its a transporter”
- Transporter in enterocyte that moves Fe from gut into blood
What is transferrin?
- Binds Fe in blood taking in from ferroportin and either takes it to liver or macs for storage
How is Fe stored?
- In cells bound to ferritin
That does TBC tell us?
- How much transferrin is in blood
Cause of Fe Deficiency anemia in adults in developing world?
- Hookworms
Fe2+ or 3+ more readily absorbable? How is 2 maintained
- 2+, think “Fe2 goes IN TWO the body”
- Acidity keeps Fe in 2+ state
How does gastrectomy lead to Fe anemia?
- Stomach is a very acidic place
- Acid keeps Fe in 2+ from
- 2+ is more absorbable
* **Thus, if we remove stomach and its acidic environment, we have more Fe3+ which is more absorbable
Relation to Ferritin and TIBC?
Inverse:
- When ferritin goes up, TIBC goes down
- When ferritin down, TIBC up
* **Makes sense because if ferritin is low, Liver will realize body needs more Fe so will make more transferrin thus increasing TIBC
What is the first stage of Fe deficient anemia?
Normocytic: marrow wants to make normally pretty RBCs so will make them with normal Fe in then, but will just make fewer for them
- Eventually this becomes microcytic
What is koilonychia?
“Spoon shaped nails”
- Seen in Fe deficient anemia
What is FEP?
“Free erythrocyte protoporphyrin”
- Increased in Fe deficient anemia
- Makes sense as normal proto but low Fe, so some proto in HgB will be unbound
Explain anemia of chronic disease?
- Hepcidin is an acute phase reactant which sequesters Fe into storage to bacteria can’t use
- Thus, macs can’t give to erythroblasts
- Hepcidin also suppresses EPO
What is hepcidin?
- Acute phase reactant responsible for anemia chronic disease as it functions to:
1. Sequester Fe to save from bacteria
2. Decrease EPO production
What is sideroblastic anemia?
- Defect in protoporphyrin synthesis = microcytic anemia
Steps in protoporphyrin synthesis?
- Succinyl CoA converted to aminolevulinic acid (ALA): ALA synthase catalyzes
- Rate limiting step with B6 as cofactor - ALA -> porphobilinogen: ALA-dehydrogenase
…… - Fe joined to protoporphyrin by ferrochelatase: occurs in mitochondria
Importance of B6 in sideroblastic anemia?
- B6 is cofactor for ALAS which converts SCoA into ALA: rate limiting step
What does ferrochelatase do?
Joins Fe to protoporphyrin
Mitochondrial significance on sideroblastic anemia?
- Sidero is problem with protoporphyrin synthesis
- Ferrochelatase combines Fe and proto in mitochondria of erythroblast
- If mitochondria not making enough proto, Fe will still be entering cell and accumulate in mitochondria ringing nucleus “Ringed sideroblasts”
Normal cause of sideroblastic anemia?
Defect in ALAS: converts SuccCoA -> ALA which is rate limiting step in protoporphyrin synthesis
Acquired causes of sideroblastic?
- Lead: denatures ALAD and ferrochelatase
- Alcohol: mitochondrial poison
- Deficient B6: ALAS cofactor
When is B6 deficiency seen?
Isoniazid treatment
What does Isoniazid treatment predispose for?
- B6 deficiency = sideroblastic anemia as B6 is cofactor for ALAS which is rate limiting enzyme in protoporphyrin synthesis
What findings in sideroblastic?
This is an Fe overloaded state: "imagine that as the Fe is accumulating and ringing the nucleus, it is leaking out into blood" Ferritin: increased TIBC: decreased Serum Fe: Increased % Sat: increased
What is thalassemia?
Decreased production of globin chains = decreased HbB = microcytic anemia
What are carriers of thalassemia protected against?
- Plasmodium falciparum
2 types of thalassemia?
Alpha: decreased A chains
Beta: decreased B chains
Difference in HbA and HbA2?
HbA: 2 alpha and 2 beta chains
HbA2: 2 alpha and 2 delta chains
Is the alpha or beta globin chain more important?
Alpha: is present in fetal, HbA, and A2
- Beta chain is only present in HbA
Genetics of A-thalassemia?
- There are 4 alpha alleles on chromosome 16
- DELETION leads to varying degrees of A thalassemia
Degrees of A-thalassemia?
- 1 allele: asymptomatic
- 2 alleles: cys or trans
- 3 alleles: severe anemia HbH damages RBC
Explain cis and trans A thalassemia?
4 alleles for A chain on chromosome 16
Cys: knock out 2 alleles on some chromosome
1. Worse: can pass both to offspring
2. Seen in asians
Trans: knock out 2 alleles on diff chromosome
1. Seen in africa
2. Less severe: lower risk of passing to offspring
What occurs in A-thalassemia with 3 alleles?
- B chains form tetramers (HbH) that damage RBCs
- Fetal HgB does not show issues
What is HbH?
- Tetramer of B globin seen in A thalassemia with 3 allele deletion
- Damages RBCs
- Not present in fetus
Genetics of beta thalassemia?
- 2 alleles on chromosome 11
- Due to MUTATIONS (A was due to deletion)
1. Beta null: one allele cant produce any
2. B+: decreased from one allele
What are target cells?
Blebs of hemoglobin in normally concave /pale central RBC
- Decreased cytoplasm
- Increased membrane
* **Think like deflating basketball making its surface more malleable
What is B thalassemia minor?
- One normal B allele and one B+
- Slightly decreased HbA
- Slight increase HbA2 (delta for beta)
What si B thalassemia major?
- Double B null
- Fetal HbG is protective at birth
- Rapid regression after
- Alpha tetramers damage RBCs
- Massive erythroid hyperplasia: in other organs
Which anemia is massive erythroid hyperplasia seen in? Presentation?
B Major
- Expansion of skull and facial bones: “crew cut appearance on Xray”
- HSM: spleen starts making again
When are circulating RBCs seen?
B major: being made in places other than marrow allowing nucleated cells to sneak out
2 most common causes macrocytic anemia?
- B12
2. Folate
Broad problem in macrocytic anemia?
- Cells undergo one LESS division due to lack of DNA precursors
What takes methyl group from THF so it can participate in DNA synthesis?
B12 - B12 then gives methyl to homocysteine
What takes methyl group from B12?
Homocysteine - becomes methionine once it receives the methyl group
Presentation of B12/folate deficiency?
- Megaloblastic anemia
- HYPERsegmented neuts
- MEGALOblastic change in all dividing cells: ie, epithelial cells of gut would be larger
Other cause of macrocytic anemia?
- Alcohol
- Liver disease
- Drugs - 5 fu
Where is folate found?
- Green vegetabls and fruits
- Absorbed in jejunum “Iron First Bro”
How does methotrexate cause megaloblastic anemia?
Inhibits dihydrofolate reductase = folate deficiency
Presentation of folate deficiency?
- Glossitis
- Increased homocysteine
- Normal methylmalonic acid: B12 converts this to succinyl CoA
- Hypersegmented neuts
In megaloblastic anemia, what does normal methylmalonic acid tell us?
- B12 levels are normal: B12 converts this to succinyl CoA
What is R binder?
- Protein made by salivary gland to bind B12 in mouth
- Cleaved in SI by proteases allowing to bind IF` from parietal cells in stomach
- Absorbed in ileum when bound to IF
Folate of B12 deficiency take longer to develop?
B12: Body has very low folate stores
*There are large stores of B12 in liver
Cause of low B12 other than pernicious?
- Pancreatic insufficiency: no R binder cleavage
- Ileal damage in crohn’s
- Diphyllobothrium latum
Dietary cause of low B12?
Vegans
When is glossitis seen?
- Plummer vinson
2. Megaloblastic anemia
When is methylmalonic acid elevated?
B12 deficiency as B12 converts to succinyl CoA
What causes subacute combined degeneration? How?
B12: methylmalonic acid builds up in myelin of spinal cord
2 main classes of normocytic anemia?
- Underproduction: low retic
2. Peripheral destruction: normal retic
What do reticulocytes look like?
- Bigger than normal
- Slightly blue cytoplasm: RNA still in cytoplasm
What is normal retic count?
1-2%
- If there is anemia and marrow works, should be >3%
Why is retic falsely elevated in anemia?
- Retics are measured as % of total RBC
- Anemia = low RBCs = inaccurate calc
- *Need to adjust
How is the retic adjusted?
Multiply by hematocrit / 45
Where are RBCs destroyed in extravascular hemolysis?
RES system:
- Liver
- Lymph nodes
- Macs in spleen
What does protoporphyrin become?
Unconjugated Bilirubin
Presentation of extravascular anemia?
- Splenomegally
- Unconjugated jaundice: liver can’t keep up w/ spleen
- Bili stones
- Hyperplastic marrow
What is haptoglobin?
- When RBCs destroyed in vessels, haptoglobin binds HgB and takes it to spleen
Lab findings in intravascular hemolysis?
- Decreased haptoglobin
- Hemoglobinuria
- Hemosiderinuria: Fe in tubular cells eventually is sloughed off into urine
- Hemoglobinemia
What is going on in spherocytosis?
- Normally, cytoskeleton is anchored to membrane via ankyrin and spectrin giving RBC its its biconcave shape
- Tethering is lost in sphero, leading to blebs coming off and transition to sphere shape
Why does spherocytosis cause anemia?
- Loss of biconcavity prevents spherocytes from moving through spleen
- Spleen eats them = anemia
What is MCHC and when is it seen?
“Mean corpuscular hemoglobin []”
- Increased in spherocytosis as cell is shrinking in size as it blebs leading to greater []
Diagnosis in spherocytosis?
- Increased fragility in hypotonic solution in osmotic fragility test
Treatment of spherocytosis?
Splenectomy: RBCs still work fine spleen is just eating them
1. Howell Jolly bodies will still be seen
What are howell jolly bodies?
RBCs that still have a bit of nucleus left in them
- Normally is spleens job to remove these but if spleen is gone you will see these
- Appear as RBC with little blue spots in them
What causes sickle cell?
- Mutation in B chain of HgB replacing glutamic acid (hydrophilic) with valine (hydrophobic)
How does HbS causes disease?
- Polymerizes into needle like sickle cells when deoxygenated / stressed
How does hydroxyurea help in sickle cell?
HbF is protective in sickle cell
- Hydroxyurea causes this to form
Is sickle intra or extravascular?
Both: spleen eats them and some also rupture iin the vessels
What does sickle form target?
- Membrane damage dehydrates cell cytoplasm
- This makes the basketball effect we talked about before where the membrane is now malleable
- HgB can now move to center of cell making int darker instead of the area of pallor
What is dactylitis?
- Swelling of bones in hands / feet due to vaso occlusive infarcts of bones
* Common presentation of sickle cell in kids
What type of infx at risk for if now spleen?
- Encapsulated organisms
2. Salmonella paratyphi osteomyelitis
Most common cause of death in sickle?
- Kids: encapsulated orgs
2. Adults: acute chest syndrome
What does sickle do to kidney?
Renal papillary necrosis
- Hematuria and proteinuria
Where does sickle cell trait usually present?
Renal medulla: very hypoxic and hypertonic which promotes sickling
- Leads to microinfarcts, microalbumin, and inability to [] urine
What does metabisulfite do?
Used to diagnose sickle cell trait
- Forces cells to sickle when added
How much HbA is there in sickle cell?
Zero: HbA is 2 alpha and 2 beta
- In sickle the issue is with both alleles of the beta chain so we have no beta
What is hemoglobin C disease?
- B globin mutation of glutamic acid for lyCCCCine
- Less severe with HbC crystals seen in smear
What are MIRL and DAF?
Both found on surface of RBC and serve to inactivate complement when it comes close to RBC:
DAF: “Decay accelerating factor”
MIRL: “Membrane inhibitor of reactive lysis”
***Both connected to RBC surface by GPI
What is GPI?
Connects both DAF and MIRL to RBC membrane protecting them from complement
- Is deficient in PNH
What happens to acid base status at night? How does it cause PNH?
- Breathe shallow increasing CO2 creating respiratory acidosis in body
- Acidosis can activate complement and this is what happens in PNH
- Wake up with dark urine as activation of complement leads to RBC lysis
What is PNH?
“Paroxysmal nocturnal hemoglobinuria”
- Defect in GPI = no DAF / MIRL to protect RBCs from complement activation caused by respiratory alkalosis while we sleep
How do we screen for PNH?
- Place sucrose in serum to activate complement then check for lysis
- Do same with acid
- Screen for DAF / CD55
What other disease is at risk in PNH?
AML: makes sense as PNH is problem with myeloid precursors just like AML
How do RBCs protect selves from oxidative stress?
- Glutathione reduces free radicals and is oxidized
- To used oxidized glutathione again, must be reduced by NADPH
- G6PD is required to created NADPH
What does G6PD do?
Produces NADPH so glutathione can be reduced so cell can continue to protect self from oxidative stress
What is issue with G6PD in disease?
Has a reduced half life, 2 types:
African: mildly reduced
Mediterranean: greatly reduced = cells die much younger
What causes GRPD to manifest?
- Sulfa drugs
- Primaquine
- Dapsone
- Infections
- Fava beans
Disease process in G6PD?
- Oxidative stress causes HgB to precipitate as heinz bodies
- Spleen eats heinz bodies = bite cells
Presentation of G6PD?
- Hemoglobinuria
2. Back pain
What happens in IgG Hemolysis?
Extravascular hemolysis
- IgG coats RBC, splenic macs eat it off
- Spherocytes now form
- IgG is bound in warm central body
IgG or IgM warm / cold?
IgM: cold, distal body, intravascular
IgG: warm, central body, extravascular
When is cold agglutination seen?
- Mycoplasma pneumonia
2. Mono
What does coombs test diagnose?
Hemolytic anemia:
1. Direct: presence of Ig on RBC
How does direct coombs work?
- Anti IgG added to serum
2. Will agglutinate if RBC is coated
What does indirect coombs do?
Does patient have IgG in serum
- Anti IgG and test RBCs mixed with serum
- Will agglutinate if patient had IgG in serum
Parvo B19 effect on RBCs?
- Hurts RBC progenitors halting erythropoiesis
- Anemia if already marrow stress
What is aplastic anemia?
- Damage to HSC = pancytopenia with low retic
2 useful uses of desmopressin?
- Increase factor VIII and VwF in hemophilia A and VwF disease
- Water resorption in diabetes insipidus
What does VwF increase stability of?
Factor VIII
Presentation of platelet issues?
- Prolonged bleeding time
- Easy bruising
- Mucosal bleeding
What are metalloproteinases?
Zinc enzymes that degrade ECM allowing for tumor invasion
What is PD1?
“Programmed death receptor”
- Found on surface of T cells
- When bound by its ligand leads to cell death
- If blocked can help cell fight cancer
Type of drug to treat chemo vomit?
5HT blocker
HSC marker?
CD34+
What do myeloblasts become?
- Neuts
- Basos
- Eos
How do treat chemo induced neutropenia?
- GCSF
2. GMCSF
How would infection cause neutropenia?
Most neuts will be out of blood and in tissue in sever infx so they would not be measured on a blood test
What is not developed in digeorge?
3/4 pharyngeal pouch: lymphopenia as no thymus
How does cortisol cause lymphopenia?
Induces apoptosis in lymphocytes
Cell in body most sensitive to radiation?
Lymphocytes
2 things causing neutrophilic leukocytosis?
- Tissue necrosis
2. Bacterial infx
What is a left shift?
Immature neuts in blood: characterized by decreased FC receptors that would recognize Ig so they dont function as well
What does decreased CD16 mean?
Immature neuts in blood as this is for FC receptor
Marker for immature neuts?
Decreased CD 16
Cortisol impact on neuts?
Disrupts adhesion of marginated cells attached to vessels causing them to enter serum = neutrophilia
3 scenarios for eosinophilia?
- Parasitic infx
- Allergy
- Hodgkin’s lymphoma: caused by increased IL5
When is basophilia seen?
CML
Change in cell count in CML?
Basophilia
Change in cell count in CML?
Basophilia
Cells responsible for viral infx?
CD8
Bordetella pertussis impact on blood count?
Lymphocytosis: clocks T cells from leaving blood to enter nodes so count goes up
Mono impact on cell count?
Lymphocytosis of CD8
What is found in cortex and paracortex of nodes?
Cortex (outer most) - B cells
Paracortex - T cells
What is periarterial lymphatic sheath?
Area surrounding artery in spleen where T cells are found
- Area responsible for splenomegaly in mono
What does the monospot test do?
- Detects heterophile IgM antibodies seen in mono
- **Does not detect CMV
- Need to follow up test with test for EBV viral capsid antigen
What happens if you give penicillin to mono patient?
- Get a rash
What is hallmark of acute leukemia?
- MyeloBLASTS and lymphoBLASTS cannot mature to begin to pile up
- **> 20% blasts in marrow is diagnostic
Acute presentation of leukemia?
- Blasts are pushing out other cells in marrow:
a. Anemia
b. Thrombocytopenia
c. Neutropenia - High blast count in serm
Blasts on histo?
Large basophilic cell with punched out nucleus (nucleolus)
Difference between AML and ALL?
ALL: Accumulation of LYMPHOblasts
AML: accumulation of MYELOblasts
What is TDT positivity indicative of?
LYMPHOblasts: DNA polymerase only found in there nucleus
How to tell LYMPHOblast from MYELOblast?
AML: MPO+ = AUER rods
ALL: TDT+
What is MPO positivity indicative of?
AML - in crystallized form becomes auer rod
When are auer rods seen?
AML - this is crystallized MPO on staining
Common person ALL found in?
> 5 yo kid with Down syndrome
Cancer seen in > 5 yo kid with Down syndrome?
ALL
How to tell B-ALL from T-ALL?
BOTH are TDT positive:
B-ALL: CD 10, 19 20
T-ALL: CD2 - 8 (think T cells are usually 4 and 8)
What are the following markers for CD 10, 19 20?
B-ALL
B-ALL treatment?
Great response to chemo with prophylaxis needing for scrotum and CSF - think, BALL affects your BALLS
- Chemo cannot cross barriers here so needs to be injected
Translocations in BALL?
19 - 21: kids, good prognosis
9 - 22: Adults, poor prognosis
Cancer with CD 2 - 8 markers?
TALL
Presentation of TALL?
TTTHymic mass in TTTTeenager
***Actually called a lymphoma since there is a mass whereas a leukemia means cancer is in serum
Common mutation in AML?
15 - 17 translocation
- RAR disruption = promyelocytic accumulation
What is 15 - 17 translocation seen in?
AML
Treatment for AML?
All trans retinoic acid causes cells to mature “ATRA”
What is ATRA treatment for?
AML
What should you think if patient has cancerous swelling of gums?
Acute MONOcytic leukemia
Cancer in down > 5 yo?
5: ALL
What are myelodysplastic syndromes?
CYTOpenias with Hypercellular bone marrows that can cause leukemias arising in background of radiation
What is chronic leukemia?
Malignant proliferation of MATURE circulating LYMPHOcytes
- Characterized by high WBC count
What is CLL?
- Proliferation of Naive B cells
- Express CD 5 and 20
- Increased lymphocytes and smudge cells seen on smear
What is CD 5/20 indicative of?
CLL
When are smudge cells seen?
CLL
Complications of CLL?
- HYPOgammaglobulinemia: B cells are not maturing to secrete Ig as they should
* Most common cause of death = infx - Autoimmune hemolytic anemia: B cells are making messed up Ig that is attacking self
- Transform to diffuse large B cell lymphoma
What is hairy cell leukemia?
- Malignant proliferation of mature B cells
- TRAP positive
- Hairy cytoplasmic processes
What is TRAP + indicative of?
Hairy cell leukemia, think “Look out, its a hairy TRAP!!!!!!!!”
Hairy cell presentation?
- Splenomegally in red pulp: atypical
- Absent lymphadenopathy
- Dry tap on marrow aspiration
Think, they are TRAPPED in spleen so can make it nodes or marrow
Hairy cell treatment?
2-CDA: adenosine deaminase inhibitor causing adenosine to accumulate to toxic levels in B cells
What is ATLL?
“Adult T cell leukemia / lymphoma”
- Neoplasm of Mature CD4+ T cells
- HTLV1 association in caribbean and japan
Cancer to think if HTLV1?
ATLL “Adult T cell leukemia / lymphoma”
Presentation of ATLL?
- Rash: T cells like to go to spleen
- Lymphadenopathy
- Splenomegally
- Lytic bone lesions and HYPER Ca
Blood cancer with lytic bone lesions?
ATLL
What is mycosis fungoides?
- Neoplasm of mature CD4+ T cells presenting with:
1. Skin rash, plaques, nodules
2. Pautrier microabscesses in skin
3. Sezary syndrome: cerebriform nuclei on smear
When are Pautrier microabscesses seen?
Mycosis fungoides
When is cerebriform nuclei on smear seen?
Mycosis fungoides
What is a myeloproliferative disorder?
- Accumulation of mature myeloid cells
- All myeloid cells are increased but classified on dominant form
Associated risks in myeloproliferative disorders?
- Hyperuricemia / gout: developing lots of cells so turning over rapidly
- Marrow fibrosis
- Transform to acute leukemia
What is end result of purine degradation path?
Uric acid
What is CML?
“Chronic Myeloid leukemia”
- Predominant proliferation of granulocytes
- Basophils are characteristically overproduced
Mutation in CML?
- 9/22 BCR/ABL fusion = increased TK activity
What is imatinib treatment for?
CML
How to treat CML?
- Imatinib: blocks overexpressed TK activity
Worst CML complication?
Transformation to acute leukemia: AML or ALL
3 ways to distinguish CML from leukemoid rxn:
Leukemoid is natural increase granulocyte to infx. In CML we have:
- LAP negative granulocytes
- 19/22 translocation
- Increased basophils
What is polycythemia vera?
Neoplastic proliferation of RBCs
- Granulocytes and platelets also increased
- JAK2 kinase mutation seen
What is JAK2 mutation seen?
- Polycythemia vera
- Essential thrombocythemia
- Myelofibrosis
Symptoms of polycythemia vera?
Hyperviscosity of blood:
- Blurry vision and headache
- Thrombosis: bud chiari
- Flushed face
- Itching after bathing: mast cells degranulate in hot water
When is itching after bathing seen?
Polycythemia vera: mast cells degranulate in hot water
Most common cause of budd chiari?
Polycythemia vera
Treatment for polycythemia?
- Phlebotomy
2. Hydroxy urea
What is hydroxyurea used to treat?
Polycythemia vera
*Also useful in sickle cell as it causes HbF to form
Characteristics of reactive lung disease from polycythemia?
- Low O2
2. Increased EPO
Mutation in essential thrombocythemia?
JAK2 kinase
What doesn’t thrombocythemia not have risk for gout/hyperuricemia?
- Platelets do not have nucleus so not creating uric acid via purine degradation path when being demolished
What is myelofibrosis?
- Neoplastic proliferation of megakaryocytes
- JAK2 mutation
- Are secreting excess PDGF = marrow fibrosis
What is fibrosis of marrow seen in?
Myelofibrosis: driven by JAK2 mutation in megakaryocuytes
When is leukoerythroblastic smear seen?
Myelofibrosis:
- The marrow is shot so extramedullary creation of cells occurs
- Places outside of marrow cannot filter immature cells so we are seeing blasts of all types in the smear
When are tear drop cells seen?
Myelofibrosis
What is multiple myeloma?
- Malignant growth of PLASMA cells in bone marrow
- High IL6 often seen: important plasma cell growth factor
What is high IL6 indicative of?
Multiple myeloma: important plasma cell growth factor
What does multiple myeloma cause back pain with hyper Ca?
- Plasma cell releases osteoclast activating factor which turns on RANK on the osteoclasts
- Lytic lesions seen in vertebrae and skull
- Increased risk of fracture
Multiple myeloma presentation?
- Increased fracture risk
- Lytic bone lesions
- Hyper Ca
- Risk for infx: Increased Ig lacks antigen diversity
- Primary AL amyloidosis: plasma overproduces light chain
- Proteinuria: bence jones proteins
- Renal failure: same as above
What does electrophoresis look like in multiple myeloma?
“M Spike” monocolona Ig
- Spike in gamma region from increased IgG
- **Most commonly is IgG or IgA
When is rouleaux formation seen?
Multiple myeloma from increased Ig causing RBCs to aggregate
When are bence jones proteins seen?
Multiple myeloma: these are the same excess light chains being excreted that are causing the amyloidosis
What to think if M spike seen but not other myeloma features?
MGUS “Monoclonal gammopathy of unexplained significance”
What is waldenstrom macroglobulinemia?
- B cell lymphoma with monoclonal IgM
What are langerhans cells?
Dendritic cells of skin
What is langerhans cell histiocytosis?
- Neoplastic langerhan cell proliferation
- Birkbeck / tennis racket cells on EM
- CD1a/s100 positive
When are Birkbeck / tennis racket cells seen?
Langerhans cell histiocytosis
When are CD1a/s100 positive cells seen?
Langerhans cell histiocytosis
What is eosinophilic granuloma?
Benign proliferation of langerhan cells in bone
- Pathologic fracture in kid with no skin involvedment
What to think when pathologic fracture in kid with no skin involvement?
Eosinophilic granuloma
When are painful and painless lymphadenopathy seen?
Painful: acute infx being drained
Painless: chronic infx, cancer, lymphoma
When are lymph node follicles enlarged?
- RA
2. Early HIV
When are lymph node para cortexes enlarged?
Viral infx: this is where T cells live
When are sinus histiocytes of nodes enlarged?
Draining tissue with cancer
What lives in medulla, cortex, and paracortex of LN?
Cortex: B cells
Paracortex: T cells
Medulla sinus histiocytes
What is lymphoma?
Proliferation of lymphoid cells that forms a mass
- Can be in node or outside
2 major types of lymphoma?
- Hodgkins: 40%
2. Non hodgkin’s: 60%
Where is mantel found?
- Surrounds follicles which are found in cortex
Where is marginal zone found?
Surrounding mantle zone with surrounds the follicle which is found in cortex
3 lymphomas arising from small B cells?
- Follicular
- Marginal
- Mantle
What is CD20 marker for?
B cells
What is follicular lymphoma?
- CD20 B cells making follicle like nodules
- Painless generalized lymphadenopathy throughout body
Genetics of follicular lymphoma?
- 14:18 translocation of heavy chain / BLC2
- IgH is highly expressed so BCL2 now is overexpressed
What does BCL2 do?
- Stabilizes mitochondrial membrane preventing cytochrome C from leaving and killing
- Overexpressed in follicular lymphoma = indestructible self reactive B cells which no longer can be killed
When is 14:18 translocation of BLC2 seen?
Follicular lymphoma: BCL2 stabilizes mitochondrial membrane preventing cytochrome C from leaving
- Indestructible self reactive B cells which no longer can be killed
Follicular lymphoma treatement?
Rituximab: anti CD20 Ig
How to distinguish follicular lymphoma from hyperplasia seen in rxn to normal infx?
- BCL2 expression in follicles
- Monoclonality: polyclonal expansion is seen in infx
- Lack of tingible body macs in germinal centers: you expect to see macs if infx
What is mantle cell lymphoma?
- Neoplastic CD20 B cells expand in mantle zone “area immediately adjacent to follicle”
Mutation driving mantle cell lymphoma
- 11:14 translocation placing Cyclin D next to IgH
- Overexpression of cyclin D allows cells to move from G1 - S phase when they should not
Where is the Ig Heavy chain found?
Chromosome 14
What does cyclin D do?
Help cell move from G1 - > S phase
Is marginal zone always present in LN?
- No, when there is infx and germinal centers form the marginal zone forms
What is marginal zone lymphoma associated with?
- Hashimotos
- Sjogren’s
- H pylori
2 forms of Burkitt lymphoma?
African: jaw mass
Sporadic: abdominal mass
Burkitt’s genetics?
- 8:14 translocation of cMYC oncogene which promotes cell growth
- Starry sky appearance on histo
When is starry sky appearance seen?
Burkitt’s
What is diffuse large B cell lymphoma?
- Large B cells that grow diffusely in sheets
- Most common NHL
- Very aggressive
What occurs in hodgkin’s lymphoma?
- Reed sternberg cells secrete cytokines that dram in inflammatory cells leading to mass
What are reed sternberg cells?
- Found in hodgkin’s lymphoma
- CD15/30 +
- Large B cell with prominent nucleoli and multilobed nuclei
What cell is CD15/30?
Reed sternber
Presentation of nodular sclerosis?
- Enlarging cervical/mediastinal node in young female
- Fibrosis dividing nodes with RS cells in lacunar areas
Lymphocyte rich or depleted have better prognosis?
Rich
What does IL5 do?
Call in eosinophils
When are Bite cells seen?
X linked G6PD deficiency
Inheritance of enzymes and proteins?
Enzymes: recessive
Proteins: autosomal dominant
When are acanthocytes seen?
- Liver disease
2. Abetalipoproteinemia
When are target cells seen?
"HALT" when you reach the target Hemoglobin C disease Asplenia Liver Disease Thalassemias
When are Heinz bodies seen?
Heinz G6PD deficiency, which the spleen taking a bite out of them
2 main categories of microcytes?
- Problem making heme
2. Problem making globin
When is basophilic stippling seen?
Lead poisoning
How to treat lead poisoning?
- Dimercaperil
- EDT
- Succinyl CoA
What to give in patient low in clotting factors?
Fresh frozen plasma`
What is cryoprecipitate?
Factor VIII, XIII, VwF, fibrinogen
What does TNF-alpha do?
Responsible for cachexia seen in cancer: causes appetite suppression and increased BMR which makes senses when you think about symptoms
What is start codon in translation?
AUG - “translation starts in august”
What does rituximab do?
Target surface CD120
Signs of carcinoid?
- Flushing
- Bronchospasm
- Watery Diarrhea
- Right heart valve plaques
What is increased 5 HIAA in urine indicative of?
Carcinoid: this is a metabolite of 5HT - think that they both start with 5 H so makes sense that is metabolite
Lab studies in hemolytic anemia?
- Increased LDH
2. Decreased Haptoglobin
Importance of folic acid in DNA synthesis?
Carbon donor required for purine and pyrimidine synthesis
Inheritance of G6PD?
X recessive
Mechanism of allopurinol?
Xanthine oxidase inhibitor
What does RB do and how is it regulated?
Regulates G-> S transition
- Dephosphorylated: active, cell cant progress
- Phosphorylated: inactive, done by cyclins, cell progreses
What reduces hemorrhagic cystitis seen in chemo?
MENSA
KRAS, APC, BRCA1, RB oncogene or tumor suppressor?
KRAS: Proto oncogene APC: suppressor BRCA1: suppressor RB: suppressor TP53: suppressor
Function of MYC?
Oncogene that is a transcription activator
Which opioid side effects do not go away?
- Constipation
2. Miosis
Disease process in inflammatory breast cancer?
- Cancer cells obstructing lymphatic draining to breast leading to peau d’orange presentation
What is fibronectin responsible for?
Cell adhesion
When is FFP administered?
Warfarin OD
Treatment of warfarin OD?
FFP
- K also works but takes days
Treatment of heparin OD?
Protamine sulfate
*****FFP does not work as it contains ATIII which will potentiate warfarin
What do POL gene mutations convey?
In HIV, this conveys proteases that are resistant “paul the black smith”
- Also can render reverse transcriptase resistant