Haematology - Coagulation and Bone Marrow in Health and Disease Flashcards
Haematopoiesis
The process from which blood cells are produced and developed from a pluripotent stem cell
Where does haemopoiesis occur in the foetus
Foetal yolk sac, liver, spleen and lymph nodes
Where does haemapoiesis occur in babies in children
All bone marrow (red marrow —> yellow marrow)
Where does haemopoiesis occur in adults
Bone marrow of axial Skelton and proximal long bones
Extramedullary haematopoiesis
Haemaopoiesis occurring ourisde of the bone marrow e.g. liver and spleen
When does extra medullary haematopoiesis take place
Bone marrow disease e.g. myelofibrosis when marrow becomes occupied w/ fibrotic tissue
Yellow (fatty) marrow can also be recruited top produce blood cells
What may extramedulalry haematopoiesis lead to
Enlargement of liver +/- spleen
Erythropopiesis
Production and development of red cells
Production and development of granulocytes
Granulopoiesis
Thrombopoiesis
Production and development of platelets
Function of maegakaryocytes
Produce platelets and stay in bone marrow - does not pass into blood stream
Properties of haemopoeietic stem cells
Differentiation
Self-renewal
How long does it take for a stem cell to become a formed blood cell
2-3 weeks
How does the micorenevornment affects the function of haematopoietic stem cells
Growth factors
Interaction w/ neighbouring cells
Examples of growths factors stimulating different haematopoietic stem cells
Epo Tpo IL-5, IL-6 G-CSF M-CSF GM-CSF
Composition of blood
Specialised connective tissue w/ 4 main components: RBC, WBC, plasma and platelets
Where are blood cells found in the blood
Suspended in plasma
Blood volume in M and F
5-6L in M
4-5L in F
Cells formed from myeloid progenitor cells
RBC
Platelets
Granulocytes - eosinophil, basophil, neutrophils
Cells formed from lymphoid progenitor cells
B cells
T cells
NK cells
When will affected cell lineage number go up in the blood
If the stem cells is ‘overactive’ either because of clonal genetic defect (mlaignancy) or because environment drives activity
Why must haematoppoiesis be regulated
Blood cell production must match blood cell destruction
Production may need to be increased in certain situation e.g. bleeding, infection
How do haematopoietic growth factors affect cell production
Stimulate increased production
Red cells and erythropoietin (epo) feedback loop
Low blood oxygen causes liver and kidney to please epo into bloodstream
This increases number of red cells and increases oxygen-carrying capacity
Why might a high blood count occur
Primary - abnormal bone marrow
Secondary - normal bone marrow
Red cell destruction due to asnet or poorly perfuming spleen (hyposplenism)
Which is the most common reason for high blood counts
Secondary causes
Primary causes of leucocytosis
Leukaemia
Lymphoma
Myeloproliferative disorders
Bone marrow must be treated/ managed
Secondary causes of leucocytosis and thrombocytois
Infection Infl Infarction Tumour Stress/ trauma - leucocytosis only
Example of a condition causing primary thrombocytosis
Essential thrombocythemia
Treat/ manage bone marrow e.g. hydroxycarbamide
What is haematocrit (Hct)
Ratio of RBC to total blood volume
True erythrocytosis vs apparent polycythemia
True erythrocytes ‘polycythemia’ is an increased number of red cells (increased Hct)
Apparent polycythemia is caused by reduced plasma volume
Primary causes of erythrocytosis - clonal stem disorders
Polycythemia vera
Treat/ manage the bone marrow e..g venesection +/- hydroxycarbamide, plus aspirin
Causes of apparent polycythemia
Overweight
Smoking
Alcohol excess
Medications e.g. diuretics
Secondary causes of erythrocytosis - raised epo
Low oxygen in the blood e.g COPD Tumours Doping High affinity Hb - high altitudes Polycystic renal disease L to R shunt in heart
What can polycythemia vera and essential thrombocythemia lead to in untreated
Thrombosis
Reasons for low blood counts
Underproduction
Reduced survival in the circulation
Reasons for leucopenia - underproduction
Drugs affecting stem cells e.g. chemo
Part of pancytpenia due to marrow failure
Reasons for leucopenia - reduced survival
Autoimmune
Drugs
Consumption - flu
Combi e.g viral hepatitis - both the virus and drugs used to treat cause reduced survival
Reasons for thrombocytopenia - underproduction
Drugs affecting stem cell
liver failure (tpo underproduction)
Part of pancytopenia due to marrow failure
Reasons for thrombocytopenia - peripheral destruction
Autoimmune (ITP)
Hypersplenism (hiding in the spleen)
Drugs
Infections/ infl/ sepsis increases consumption of platelets
Hypersplenism
Inappropriate removal of erythrocytes, granulocytes or playlets from blood
What do pts w/ hypersplenism characteristically have
Splenomegalyu
Destruction or pooling of 1/1+ by the cell —> release of immature cells in PB
Normal bone marrow
Drugs causing peripheral destruction of platelets
Penicillin
Furosemide
NSAIDs
Reasons for low blood counts caused by reduced production
Myeloma - bone marrow overrun w/ functionally useless cells; normal cells incl stem cells crowded out Myelodysplasia Metastatic malignancy Myelofibrosis Leukaemia Lymphoma Aplastic anaemia Haematininc deficiency
Aplastic anaemia
Empty bone marrow cased by stem cell failure
Can be primary or most commonly secondary e.g. drug-induced, viruses
BM no longer produces blood cells
What does haematinic deficiency cause in blood counts
Pancytopenia
White cell malignancies divided by lineage
Myeloid cells - AML, myeloproliferative disorders and myelodysplasia
Lymphoid cels - ALL, CLL, lymphoma, myeloma
White cell malignancies of immature cells (blasts)
AML
ALL
White cell malignancies of mute cells
Myeloproliferative disorders Myelodysplasia CLL Lymphoma Myeloma
What are the myeloproliferative disorders
Polycythemia Vera (PV)
C/c myeloid leukaemia (CML)
Essential thrombocythemia (ET)
Myelofibrosis
Myledysplasia (MDS)
Haematopoietic stem cell malignancies, related to myeloproliferative disorders
Abnormal maturation as well as abnormal proliferation in BM
Dysplastic cells don’t get into blood
What does MDS present with on a FBC
Pancytopenia
What % of MDS pts evolve into AML
20%
Myelofibrosis
Malignant proliferation of reticulin fibres in bone marrow
Features of myekofibrosis
Anaemia
Leucoerythroblastic blood film
Splenomegaly
What can myelofibrosis dveelpi from
MPN or be primary
MPN
Myelo proliferative neoplasms
What can myelofibrosis transform into
AML
Causes of low blood counts w/ normal bone marrow (reduced cell survival)
Immune cellular destruction
Drugs
Haemorrhage
Hypersplenism
When would you see Auer rods on a blood film
Acute (myeloid) leukaemia - blasts
Causes of hyposplenism
Splenectomy e.g. therapeutic or due to trauma
Auto-infarction e.g SCD
Infiltration e.g metazoic malignancy
Under-functioning e.g. coeliac disease
Hyposplenism on a blood film
Howell-Jolly brides
Target cells
Acanthocytes
Causes of neutrophilia
Bacterial infection ** Infl cords Burns Cigarette smoking Steroids (glucocorticosteroids) G- CSF Solid tumours Myeloproliofertiave disorders e.g. CML *
General causes of lymohocytosis
Viral infections e.g. EBV * Hypospleinsim TB Brucellosis CLL Lymph. w/ 'spillover'
General causes of eosinophilia
Allergic reaction - most common Vasculitis Drugs Worm infestations Cancer (esp solid tumours and lymphoma)
Most common causes of microcytic anaemia
IDA
ACD
Most common cause of microcytic anaemia
Vit B12 or folate déficiency - causes pancytopenia
What addn info can we get from a blood film
Morphology of rd cells, white cells and platelets
Morphology of any abnormal cells incl blasts
Blood borne infections e.g. malaria
Roleuax (stacking of RBCs), agglutinates, fibrin clots, platelet clumping
Rouleaux on blood film
Stacking of RBCs
When does rouelaux occur
In infection
Reaction condns
Myeloma
Lymphoma
Cancer of the lymph nodes
Classification of lymphoma
Hugh grade or low grade
B-cell or (less commonly) T cell
Hodgkin or Non-Hodgkin
What do lymphoma pts px with
(Painless) swellings - lymphadenopathy
+/- B symptoms
May be incidental finding on MRI
B symptoms seen in lymphoma
Night sweats
Fever
Unintentional wt loss >10% in 6/12
What may lymphoma pts present with
Hepatosplenomegaly
Symptoms related to cytopenias
Symtoms related to lumps in/compressing important structures e.g. kidneys, lungs, bowel
Pruritus
Hx of high grade vs low grade lymphoma
Short vs longer or ‘no’ hx
Growth of high grade vs low grade lymphoma
Quickly vs slowly
Which lymphoma pts are symptomatic
High grade
Difference in approach to treating high grade vs low grade lymphoma
Treatment always required immediately vs watch and wait
Which lymphoma in a lifelong illness
Low grade - not curable
Which lymphoma. treatment involves intensive chemo
High grade
How many curative opportunities are there in high grade vs low grade lymphoma
One change in high grade (or maybe two) Bute low grade can usually be treated again and again
Staging of lymphoma
Ann Arbor
Stage I (best) - IV (worst) Looks at LN and organ involvement
A: absence of B symptoms
B: B sx
How is lymphoma diagnosed
Bx of lump - core bx ro whole node excision
NOT fine needle aspirate (FNA)
Burkitt lyphoma
Very rapidly growing subtype of high-grade B-cell NHL
Genetic cause of Burkitt’s lymphoma
t(8; 14) - translocation of chromosome 8 to 14
What is endemic Burkitt’s lymphoma associated w/
EBV infection
Is Hodgkin lymphoma low-grade or high-grade
High
Epidemiology of Hodgkin lymphoma
Most common in young adults and 60+
M > F
What infection is associated w/ Hodgkin lymphoma
EBV
Px of Hodgkin lymphoma
Pruritus
Often present w/ mediastinal mass - SVC obstruction, bronchial compression (cough, SOB, stridor)
Alcohol-induced LN pain
Dx of Hodgkin lymphoma
Bx - scattered Reed Sternberg (owl eyes) cells and reactive cells
Treatment and prognosis of Hodgkin lymphoma
Different chemo to NHL
Prognosis particularly good
Imaging for lymphoma staging and response
PET scan
In which lymphoma is extra-nodal disease common
NHL
GI tract - gastric MALT lymphoma in c/c H. pylori infection, small bowel lymphoma
Skin- mycosis fungoides
Most common leukaemia
CLL
Usual findings of CLL
incidental lymphocytosis on FBC
If there is only lymphadenopathy and NO lymohocytosi, what should be suspected
Small lymphocytic lymphoma (SLL), low grade NHL
Diagnosing CLL
FBC, blood film (leucocytosis and smear cells)
Examination findings
Immunophenotyping - monoclonal antibody w/ immunological marker for CD5 and CD19
When would you treat CLL immediately
Bulk disease e.g. lymphadenopathy
Disease obstructing major organ
Bone marrow failure
B sx
‘Watch and wait’ approach is usually used
Drug treatment for CLL
Monoclonal antibody + chemo e.g. rituxumab, fludarabine and cyclophosphamide
B-cell signalling inhibitors (tablets) e.g. ibrutinib
Epidemiology of CLL
Usually >70 yrs
Generally slowly progressive
Genetic cause of CML
t(9:22) - ‘philadelphia chromosome’
Codes for a anew protein, BCR-ABL, a tyrosine kinase
Why is CML always treated when diagnosed
Can progress to AML
CML px
Incidental - neutrophilia w/ granulocyte precursors
Sx related to anaemia and splenomegaly e.g. pain and early satiety
B sx
Dx of CML
FBC (neutrophilia and presence of myelocytes) and blood film
FISH to look for Philadelphia chromosome
Bone marrow bx to assess phase
FISH
Fluroscent in-situ hybridisation
Treatment of CML
Tyrosine kinase inhibitor e.g, imatinib
Daily tablets lifelong
Aim for low levels of BCR-ABL, use PCR
A/c leukaemia px
Consequences of cytopenias e.g. bleeding, anaemia, infections
Short hx - treatment required quickly
ALL pts sometimes have lympadenopathy or hepatosplenomegly at dx
Dx of a/c leukaemia
Blasts on blood film or BM (> 20%)
Dx confirmed w/ immunophenotyping (distinguishes AML from ALL)
Epidemiology of a/c leukaemia
ALL more common in children (little people)
AML more common in elderly (mature people)
APML
A/c promyelocytic leukaemia
Subtype of AML associated w/ DIC (medical emergency)
Treatment options for a/c leukaemia
Intensive chemo, may involve allogenic stem cell transplant (may be curative, v toxic)
Low intensity chemo (may prolong life but not curatiev, still toxic)
Palliative care - sx control at home
Aside from chemo , what else to a/c leukaemia pts need
Hickman line Prophylactic antimicrobials Transfusions (Red cells, platelts) Treatment of neutropenic sepsis Pian control Antiemetics Psychological support
Haemostasis
The arrest of bleeding
What does a hyperocagulable state lead to
Thrombosis
What does reduced coagulation lead to
Bleeding disorder
Phases of CML
C/c
Acceleration
Blast - crises
Rule of 1/3 in CLL
1/3 don’t progress
1/3 progress lowly
1/3 undergoes Richter’s transformation to become aggressive high-grade lymphoma.
Features of all types of leukaemia
BM failure causing pancytopenia
B sx
Generalised painless lymphadenopathy
Hepatosplenomagly
Sx of thrombocytopenia
Bleeding
Ecchymoses (bruises)
No-blanching petechiae (smaller)/ purpura (bigger)
Specific sx of AML
Infiltration –> gum hypertrophy, skin infiltration
DIC in APML
Specific sx of ALL
Children w/ FTT
CNS involvement
Painless unilateral testcular swelling
Renal enlargement
CNS involvement in ALL
Inc cranial nerve palsies and meninges due to mets to meninges –> neck stiffness and papilloedema
Papilloedema
Optic disc swelling
Stages of haemostasis
Tissue injury –> thrombus formation -> tissue repair –> dissolution of the thrombus
How does haemostasis work?
Vasoconstriction - limits blood flow to the injured region
Formation of platelet plug
Formation of fibrin mesh - to stabilise the thrombus
Clot dissolution - through the action of plasmin
Steps of formation of platelet (primary haemostatic) plug
Adhesion - platelets come into contact w/ damaged sub endothelium
Activation - vWF factor causes platelets to adhere to ECM collagen
Aggregation - platelet-platelet interaction via fibrinogen
Examople of primary haemostasis
Von Willebrand disease
Features of Von Willebrand disease
Usually pattern = mucosal haemorrhage
Bleeding at time of trauma/ surgery
Menorrhagia
Nose bleeds
What do the symptoms of Von Willebrand disease vary according to
Amount of vWF (most commonly mild form of disease)
Secondary haemostasis
Stabilisation of platelet plug
Fibrin acts like gun giving the platelet mass strength allowing to function as a secure patch and protect the base to allow repair and healing
Purpose of coagulation
To produce a stable haemostat plug via localised fibrin clot formation at the site of vessel injury
Mechanism of blood coagulation
Enzymatic cascade of series of coagulation proteins sequentially activated and a plied which results in a fibrin clot
Coagulation pathways
Intrinsic
Extrinsic
Common
Factors in intrinsic coagulation pathway
XII —> XIIa
XI —> XIa
IX —> IXa
Factors in extrinsic coagulation pathway
VII
VII + TF —> VIIa: TF
Tissue factor released when vessels are injured
Factors in common coagulation pathway
X —> Xa: Va
II (prothrombin) —> IIa (thrombin)
III (fibrinogen) —-> fibrin (IIIa)
Congenital disorder of 2’ haemostasis
Low blood clotting factors - Haemophilia A or B
Haemophilia A vs B
A - lack of factor VIII
B - lack of factor IX
Usual pattern of haemophilia
Joints/ soft tissue bleeding
Bleeds into ‘target’ joints –> arthritis joint
Retroperitoneum
Bleeding at times of trauma/ surgery
What do the sx of haemophilia vary accord to
Amount of factor 8/9 - lower levels, worse the bleeding
Acquired disorder of 2’ haemostasis
Warfarin, liver disease (clotting factors produced in liver)
Much more common than congenital
What stops the coagulation process from forming thrombi throughout the circulation
Coagulation inhibitors
Fibrinolysis - breakdown of the fibrin clot by plasmin
Coagulation inhibitors in body
Antithrombin
Protein C
Protein S
How does fibrinolysis stop the coagulation process from forming thrombi throughout the circulation
Plasminogen —> palms
Fibrin breaks down into fibrin degradation products (FDPs) AKA D-dimers which stabilises 1’ haemostatic plug
Blood used in lab coagulation tests
Anticoagulated blood - coagulation proteins inactivated by anticoagulant (citrate) - blue bottle
Clotted blood - Coagulation proteins not present, no anticoagulant - yellow bottle
Coagulation testing
Measurement of time intakes to for a fibrin clot in plasma As the coagulation factors have been invited, an 'activator' is added to start the coagulation Different pathways (and coagulation factors) can be assessed by added different activators
Coagulation screen
Prothrombin time (PT) Activated partial thromboplastin time (APTT) Thrombin time (TT) - less commonly used
Prothrombin time
Tissue factor is added too ample of plasma along w/ Ca
Time until fibrin formation is measured by shining a light (initial solution is transparent)
What pathway does PT look at
Extrinsic and common
What factors does PT look at
VII
V, X, prothrombin, fibrinogen
Normal clotting time for PT
10-13s
When is PT abnormal
Liver disease
Warfarin
DIC
Activator in APTT
‘Contact activator’
Phospholipid and Ca
What pathway does APTT look at
Intrinsic and common
What clotting factors does APTT look at
VIII, IX, XI, XII
V, X, prothrombin, fibrinogen
Normal clotting in AOTT
24-38 s
When is APTT abnormal
Haemophilia A/B
DIC
Lupus anticoagulant
Activator in TT
Thrombin
Pathway measured in TT
Fibrinogen to fibrin
Factors TT look at
Fibrinogen
Normla clotting time for TT
14-16
When is tT abnormal
Low fibrinogen states
Causes of over coagulation
Too many cells
Deficiency of natural anticoagulants
Other coagulation abnromlaities
Too many cells causing over coagulation
Increased platelets
Increased RBCs
Other coagulation abnormalities causing overcoagulation
Factor V Leiden variant - factor V which is resistant to inactivation by Protein C
Prothrombin gene variant - elevated levels of prothrombin
What can bleeding disorders arise due to
Problems w/ blood vessel wall
Problems w/ vWF
Problems of platelets
Problems w/ the coagulation factor cascade
Inherited vascular defects that can cause bleeding disorders
Hereditary haemorrhage telangiectasia
CTD
Acquired vascular defects that can cause bleeding disorders
Senile purpura
Steroids
Scurvy
Amyloid
Causes of low platelets causing bleeding disorders
Inherited - rare
Acquired - immune (ITP, TTP), bone marrow failure, drugs
Causes of functional platelet abnormality leading to bleeding disorders
Inherited - rare
Acquired - drugs e.g. aspirin, clop, uraemia (renal failure)
Inherited problems w/ the coagulation cascade
Haemophilia A (factor VIII deficiency) Haemophilia B (factor IX deficiency)
acquired problems w/ the coagulation cascade (factor deficiencies)
Drugs e.g. warfarin, heparin, DOACs
Severe liver disease
DIC
Massive blood loss
TTP
Thrombotic Thrombocytopenia purpura
Genetic cause of TTP
Absent ADAMTS13 (due to an antibody), leads to ultra large vWF multimer which binds platelets in the microcirculation
What does TTP cause
Micro thrombi and consumption of platelets
Ischaemia in critical organs
Classical pentad of TTP
Fever MAHA Renal impairment Fluctuating neurological signs - blood clots in microcirculation of brain Thrombocytopenia
MAHA
Microangiopathic Haemolytic Anaemia
Is TTP a haematological emergency
Yes - remove plasma w/ multimers
What is anticoagulant therapy
Using drugs to treat and/or prevent thrombosis
Conventionally doesn’t incl antiplatelets e.g. aspirin
Common indication for anticoagulants
Prevention of CVA in AF Treatment of VTE Prevention of recurrent VTE Prevention of valvular thrombosis/ embolism in metallic heart valves Treatment of ACS Thromboprophylaxis
Types of DOACs
Factor Xa inhibitors - apixaban, rivaroxaban, edoxaban
Thrombin inhibitors - dabigatran
Parenteral thrombin inhibitor
Argotroban
Bivalirudin
MOA of warfarin
Competitivlh natganoised vit K, which is necessary for production of clotting factors II, VII, IX and X
Speed of warfarin onset of actin
Slow, several days until therapeutic
INR calculation
INR = (PT pt/ PT control)^ thromboplastin ISI
Why are pts on warfarin monitored w/ INR
High inter-pt variation
Strength of warfarin tablets
1mg = brown 3mg = blue 5mg = pink
Warfarin monitoring
Regular monitoring needed
Pts provided w/ a yellow book
Target INR:: 2.5 (range 2-3) is the standard intensity - some indications have higher target INR range
What is the incidence of haemorrhage proportional to
INR - BUT can occur within target range
Factors affecting INR
Individual variation/ genetic
Drugs (incl alcohol) can potentiate the effects of warfarin
Diet e..g. vit k
Intercurrent illness
Mistaken dose e.g elderly, visually impaired
Implication of drugs potentiating warfarin
INR must be checked within 5 days of starting/ stopping new drugs
Types of heparins
Unfractoinated heparin (UFH) LMWH e.g. dalteparin, tinzaparin, enoxaparin
Administration of heparins
IV or s/c
Destroyed by gastric acid so oral administration not possible
What is UFH a mixture of
Different wt heparin molecules
MOA of UFH
Potentiates antithrombin increasing anticoagulant effect
Clinical uses of UFH
Initial treatment of VTE
Anticoagulant ‘bridging therapy’ to cover surgery in Hugh thrombotic risk pts
How does UFH affect clotting screen
Prolongs APTT - if used at treatment doses requires regular monitoring of APTT
Time for UFH onset of action
Immediate but large doses required for full therapeutic anticoagulant (continuous IV infusion)
When are small doses of UFH given
Thromboprophylaxis (s/c injection)
Monitoring for UFH
Large inter-person variability - measure APTT
Plasma half-life fo UFH
Short (20-120 MINS)
Potential side effect of UFH
Heparin induced thrombocytopenia (immune reaction)
Reversal agent for UFH
Protamine
MOA of LMWH
Majority of effect is anti Xa (indirectly through antithrombin)
Lesser degree of thrombin inhibition
When would you give a higher over a lower dose of LMWH
High dose for full anticoagulation
Lower dose used for VTE prophylaxis
Can APTT be used to assess LMWH effect
No
Variable effect of APTT - may be normal
Onset time of LMWH
Immediate
Monitoring for lMWH
Non required
Unless severe renal failure or extremes of body wt - can use anti Xa
What is treatment dose for LMWH based on
Wt
Excretion of LMWH
Renal - will accumulate in renal failure
Which has a longer plan a half-life out of UFH and LMWH
LMWH - so can be given for most indications
What is the risk of HIT with LMWH
Much lower than UFH
Reversal agent for LMWH
None available
APTT target for pts being anticoagulants w/ UFH
2.0
Measure APTT ration every 6 hrs until stable
MOA of fondaparinoux
Effect mediated by antithrombin
Only inhibits factor Xa
Effect of fondaparinoux in APTT
Does not prolong APTT
Onset of fondaparinous
Immediate
Monitoring for fondaprinous
None required
Excretion of fondaparinous
Renal
Administration of fondaparinous
S/c injection
Clinical uses of Fondaparinous
Treatment of VTE
Treatment of ACS
Thromboprophylaxis
Reversal agent for fondaparinous
None available
Administration of DOACs
po
Metabolism of DOACs
Part renal, part hepatic
Current clinical uses of DOACs
Prevention of CVA in AF
Treatment of VTE
Thromboprohylaxis
Initiating anticoagulation - rapid onset required vs slow induction acceptable
Rapid onset required e.g. VTE - heparin or DOAC
Slow indication acceptable e.g. AF - warfarin or DOAC
Initiating anticoagulation when rapid onset is required
Heparin - usually LMWH s/c and warfarin (po) is started at the same time. Stop heparin once INR in therapeutic range
OR DOAC but some DOACs need initial LMWH
Initiating anticoagulation when slow induction acceptable
Warfarin - start conventional does e.g. 3mg OD, arrange monitoring of INR
OR DOAC
Mx of suspected VTE using LMWH and warfarin
Start s/c LMWH on suspicion of DVT or PE (if no significant bleeding risk)
Confirm dx
Start warfarin using standardised loading schedule
Stopping LMWH after a VTE
When INR 2-3 for 2 days
Duration of anticoagulation when treating AF
Usually continues lifelong providing benefits > risks
Duration of anticoagulation therapy for VTE
1st calf vein thrombosis - 6/52
1st provoked VTE - usually 3/12
1st unprovoked VTE - minimum of 3/12 (usually 6/12), may be indefinite
2nd VTE - consider indefinite anticoagulation based on risk:benefit evaluation
What type of bleeding do we see in pts on anticoagulation
Minor skin bruising (v common) Epistaxis GI haemorrhage Muscle haemotoma Haematuria ICH (rare)
What % of pts on long term anticoagulant w/ warfarin will have an episode of major bleeding
2%
Most pts will make a full recovery from the bleeding episode providing its managed correctly
Which pts on anticoagulation have a higher risk of major bleeding
Elderly Renal failure Liver failure Recurrent falls Concurrent anti platelet or NSIAD use Alcoholism Cancer
Mx of warfarin over anti coagulation
Stop warfarin
If bleeding or INR > 8 need to reverse
Reversal of warfarin/ bleeding on warfarin
Vit K - oral or IV
PCC if major bleeding/ bleeding into critical site/ to allow emergency surgery
Reversing warfarin w/ vit K
Most of warfarin effect will have reverse 6 hrs later
Reversing warfarin w/ PCC
Immediately reverses warfarin effect by replacing clotting factors (give w/ vit k )
What is key to investigate when a pt has been over anticoagulated/ bleeding
Look for cause for over anti coagulation e.g. new drugs, alcohol, diet change, confusion about dose, diarrhoea, incorrect dose, renal failure
Mx of heparin over anticoagulation
Stop heparin - short half-life, may be sufficient
Local measures e.g apply pressure
Consider TXA
If bleeding, consider protamine sulphate
What should be checked before restarting anticoagulation after over-anticoagulation
Check risk; benefit ratio - does pt still need anticoagulant
Reversal agents for DOACs
Idarucizamab reverses dabigatran
No antidote for Xa inhibitor yet, PCC should be considered in life-threatening bleeding
Examples of haemostats caused by factor deficiencies
Haemophilia A (Factor VIII) Haemophilia B (Factor Ix) Von Willebrand disease (vWD deficiency)
Genetics of haemophilia A
X-linked monogenic disease, where the F8 gene locus lies on the long arm of the X chromosomes
Homologous recombination - inversion of Factor VIII (flip tip inversion)
Clinical subtypes of haemophilia
Mild
Moderate
Severe
Prevalence of haemophilia A
~1: 5,000 males WW
Haemophilia B prevalence
~1 :20,000 WW
Genetics of haemophilia B
X-linked recessive
Gene affected is F9
Factor IX acts as proteolytic enzyme in the coagulation cascade
Prevalence of vWD
Most common inherited bleeding disorder
Up to ~1: 100 WW
Inheritance pattern of vWD
Autosomal dominant or recessive - depends on functional impact of underlying mutation
Which chromosome if the VWF locus found on
12
What is vWF a carrier molecule for
Circulating fator VII
Also promotes adhesion of the platelets to a d aged endothelium
What is a paraprotein
Monoclonal antibody arising from a clone of lymphocytes or plasma cells
Chains in antibodies
Heavy chain - either IgG, IgA, IgM, IgE or IgD
Light chain - either kappa or lambda
Detection of paraprotein
Appears as an addn abnormal band on serum protein electrophoresis
How are serum free light chains detected
Immunoassay - detected the surface usually hidden where the light chain binds to the heat chain
Two assays - one of lambda and one for kappa
Why is the ratio of serum free light chains useful
Allows us to detect clonality - whereas a polyclonal increase in cells e.g infection will lead to a raised kappa and lambda light chains
What is myeloma
Malignant proliferation of plasma cells (>10g/L) of. a paraprotein (>30g/ L)
Clinical spectrum of myeloma
Variable - frorm asymptomatic to rapid decline and death
Epidemiology of myeloma
Makes up 1% of cancers
10-15,000 myeloma pts at any one time in the UK
Median age is 60-65yrs, rare <30
Cardinal features of myeloma
Increases bone marrow plasma cells (>10%)
Bone destruction
Paraprotein band in blood (81% of pts) - unless light chain myeloma (17%) or non-secretory (very rare, <2%)
Clinical features of myeloma
End organ damage. ‘CRAB’ criteria
Also infections and spinal cord compression (plasmacytoma or fractures)
CRAB criteria for myeloma
C - elevated calcium
R - renal failure -
A - anemia
B - bone pain
Hypercalcaemia in MM
Sx such as: Bone pain Renal stones - rare as hypercalaemia needs to be long standing Groans (abdominal pain) Psychic moans (organic psychosis) Polyuria Cardiac arrest
Renal impairment in MM
Due to Its obstructing kidney tubules
Causes deranged U&Es., proteinuria (frothy urine/ dipstick), light-chain casts on urinalysis
Anaemia in myeloma
BM infiltration and failure causing pancytopenia –> anaemia, thrombocytopenia, neutropenia
Although the levels of plasma cells are high, aren’t working properly, because the Igs secreted don’t work - immunoparesis
Mevhaism of bone disease in myeloma
Myeloma cells produced factors e.g. osteoportegrin and RANK-L, resulting in:
Activation pf osteoclasts (increased resorption)
Inhibition of osteoblasts (decreased production)
Net result = bone resorption
Bone destruction in myeloma
Lytic lesion can be imaged on Xray/ CT/ MRI/ PET
Vertebral collapse - back pain, loss of height, kyphosis, nerve compression
Pathological fractures
Paraprotein in myeloma
Serum paraproteins:
IgG in 53% pts
IgA in 25%
Light chains only in 17% (free kappa or lambda)
What haematological malignancy is IgM associated with
Lymphoma NOT myeloma
What have the measurement of Bence Jones proteins been replaced with
BJ proteins (light chains in urine) superseded by serum free light chains - to measure paraproteins
What are serum free light chins used in the dx of
Light chain myeloma and primary amyloid
Clearance fo serum free light chains
Rapid: t1/2 = 2 days vs 30 days for IgG
Ix of suspected myeloma
FBC and blood film Renal function i.e. urea, creatinine Serum Ca Serum protein electrophoresis Serum free light chains Bone marrow bx - increased plasma cells Skeletal survey
What imaging is involved in skeletal survey
CT
MRI
PET
General measures that need to be managed when treating myeloma
Renal failure Hypercalacaemia Pain Fractures Soinal cord compression Anaemia Infection Hyperviscosity Psychological distress
Mx for renal failure in MM
IV fluids (may require dialysis)
Mx for hypercalcaemia in MM
IV fluids, bisphosphonates
Mx of pain in MM
Analgesis
RT
Mx of fracture in MM
RT
Surgery
Mx of spinal cord compression
Steroids
RT
Mx of anaemia in MM
Transfusion
Erythropoietin
Mx of infection in MM
Abx
Mx of hyperviscosity in MM
Plasma exchange
Urgent chemo
Mx of psychological distress in MM
Psychological support
Which pts are treated of MM using chemo
Most common in pts over 70
For those ,70, chemo followed by high dose chemo and autologous stem cells transplant
Chemo for MM treatment
- Collection - stem cells harvested from BM or BM
- Processing - stem cell is concentrated
- Cryopreservation - frozen for preservation
- Chemo - high dose chemo and/or RT
- Infusion - thawed stem cells infused back into pt
Thalidomide in myeloma mx
Prolongs survival survival
Used as a single agent agent or with other chemo
Side effects of thalidomide in MM mx
Neuropathy VTE Sedation Constipation Phocomelia (birth defects)
Drug treatments for MM, bar thalidomide
Lenalidomide, pomalidomide
Daratumamab
Bortezonib, carfililzomin, ixazomib
Trials of new steroids
Lenalidomide, pomalidomide for MM
More potent analogues
Immunomodulatory and anti-angiogenic
Less neuropathy, sedation, constipation than thalidomide
Daratumamab for MM
Anti-CD38 antibody (expressed by plasma cells)
Bortezomib, carfilzomib, ixazomib
Proteosome inhibitors
In combi w/ steroids
How can we classify causes of paraproteinaemia
B cell or plasma neoplasms
Not associated w/ B cell/ plasma cell neoplasm
Causes of paraproteinaemia caused by B cells or plasma neoplasms
MGUS Plasmacytoma Lymphoma Primary amyloidosis Others e.g. POEMS
Causes of paraproteinaemia not associated w/ B cell/ plasma cell neoplasms
Infections e.g Hep C, HIV
CTD
Carcinomas
Transplant-related
MGUS
Monoclonal gammopathy of undetermined significance
Features of MGUS
Paraproteinaemia (lower than in myeloma i.e. 30g/L and usually <10g/L)
Bone marrow plasma cells are <10%
No CRAB criteria or end-organ damage
Prevalence of MGUS
HIgh prevalence in >80 (10%)
1% per yr evolve to myeloma
Mx of MGUS
Watch and wait
When to suspect myeloma
Paraproteinaemia (or abnormal light chain ratio) plus CRAB
Plasmocytoma
Tumoural mass plasma cells
Plasmacytoma and MM
Clonal proliferation of plasma cells identical to those in myeloma, but manifest as localised mass in bone or soft tissue solitary plasmacytoma of bone or solitary extramedullary plasmacytoma
Treatment of plasmacytoma
HIgh dose RT if truly localised i.e. no underlying myeloma
Low grade lymphoma and paraproteinaemia
Lymphoma cells making a paraprotein, usually IgM
Clinical behaviour that of a low-grade lymphoma nor a myeloma
What adds risks seems from lymphoma cells making a paraprotein
Addn risk of hyperviscosity
Amyloidosis
Insoluble protein deposits in organs
Primary amyloidosis mechanism
A protein conformational disorder associated w/ clonal plasma cells
Clonal plasma cells make light chain fragmnents which are deposited in organs as insoluble amyloid proteins —> damage to affected organ(s)
Target organs for amyloidosis
Heart Kidneys Nerves Liver Gut Skin
Result of amyloidosis in heart
Congestive cardiomyopathy
Result of amyloidosis in kidneys
Nephritic syndrome +/- renal insufficiency
Result of amyloidosis in nerves
Peripheral neuropathy
Result of amyloidosis in liver
Hepatomegaly
Result of amyloidosis in gut
Macroglossia, malabsorption
Result of amyloidosis in skin
Deposits
Diagnosing primary amyloidosis
Tissue bx
Evaluation of plasma cell abnormality
Tissue bx for primary amyloidosis dx
Bx affected organ
S/c fat aspirate
Evaluation of plasma cell abnormality for primary amyloidosis dx
FBC, U&Es, Ca Serum protein electrophoresis Serum free light chains Bone marrow bx Skeletal imaging
Primary amyloidosis treatment plan
Supportive treatments
Treatments of the underlying cause
Supportive treatment in primary amyloidosis mx
Renal transplant
Maximise cardiac function
Minimise fluid retention
Treatment of the underlying cause in primary amyloidosis mx
Chemo similar to that used for myeloma
Treat plasma cell clone rather than amyloid itself
Gradual regression of amyloid burden
Outcomes of primary amyloidosis
Progressive accumulation of amyloid
Variable, pt-spp amyloid protein turnover
Untreated prognosis 12-14 months but organ spp
Very poor w/ cardiac involvement (<6 months)
Function of lymphatic system
Maintenance of fluid balance within tissues
Absorption and carriage of water-insoluble fats from the intestines
Protection of the body through the generation of an immune response
Components of the lymphatic system
Lymphatic vessels
LN
Spleen
Thymus
Where are lymph channels found
in interstitial space
Path of superficial lymphatics vs deep lymphatics
Superficial follow veins
Deep lymphatics follow arteries
What do lymphatic channels receives
Lumbar and intestinal lymph nodes
Where does the thoracic duct enter the thorax
Aortic hiatus in the diaphragm
What part of the mediastinum is the thoracic duct found
Posterior
What does the thoracic duct
L subclavian and jugular lymphatic ducts
What does the thoracic duct open into
The angle between the L internal jugular and l subclavian veins (brachiocephalic vein origin)
What is the R lymph duct formed of
R subclavian and jugular trunks
Drains into corresponding veins on the R
Where are LNs found
Distrubuted throughout the body
What do LNs allow the interaction of
Antigens, APCs and lymphoid cells in the generation of an immune response
Where is the spleen found
L upper quadrant
Long axis in the line of 10th rib
Infective causes of splenomegaly divided by pathogen types
Bacterial - TB, endocarditis
Viral - EBV
Protozoal - malaria, leishmaniasis
Haematological cause of splenomegaly
Haemolytic anaemia
Immunological causes of splenomegaly
RhA
Sarcoidosis
Metabolic causes of splenomegaly
Rare inherited enzyme deficiencies e.g. Gaucher’s
Vascular cause of splenomegaly
Portal HTN (cirrhosis)
Neoplastic causes of splenomegaly
Lymphoma
Leukaemia
Myeloproliferative disorders
Types of lymphadenopathies
Infective
Neoplastic
Immunological
Metabolic
Causes of lymphadenopathies
Local bacterial infection
Infective mononucleosis
TB, HIV
Immunological cause of lymphadenopathies
Sarcoidosis
Metabolic cause of lymphadenopathies
Thyrotoxicosis
Classical subtypes of Hodgkin lymphoma
Nodular sclerosing - most common
Mixed cellularity - immunocompromised pts
Lymphocyte rich - far, best prognosis
Lymphocyte depleted - rare, poor prognosis
What types of Hodgkin lymphoma may progress to diffuse large B-cell lymphoma
Nodular lymphocyte predominant
Indolent subtypes of NHL incl
Follicular lymphoma
MALT lymphoma
Small-cell lymphocytic lymphoma
Difference in the spread of HL vs NHL
HL tends to spread from one to another in a contiguous manner, NHL spreads more haphazardly
Features of malignant neoplasms
Non-encapsulated Invasive Poorly differentiated Mitotic figures common Can have rapid growth Relatively anapaestic
Anaplastic
Cancer cells that divide rapidly and have little to no resemblance to normal cells
Many pleomorphic cells
Naming of epithelial cancers
Glandular: adenoma –> adenocarcinomas
Squamous: papilloma –> SCC
Naming of mesenchymal cancers
Adipose tissue - lipoma –> liposarcoma
Nervous tissue - neurofibroma –> neurofibrosarcoma
Snmooth muscle - leiomyoma –> leiomyosarcoma
Possible predisposing factor for CML
Ionising radiation
Where can the blasts in CML infiltrate
Any extramedullary site (spleen, liver, LN, skin & soft tissue)
Epidemiology of MALT lymphoma
6-7% of all B-cell lymphoma
Median age 70s
Hx of c/c infl disorder –> accumulation of extra nodal lymphoid tissue (acquired MALT)
What organism causes a gastric MALT
H. pylori
Abx tx results is remission of gastric MALTs after radiation of H. pylori
Lymphoproliferative disorders in the immunosuppressed
Primary immune disorders
Post-transplant lymphoprolifertaive disorders (PTLDs)
Iatrogenic Immunodeficicny-associated Lymphoproliferrauce disorders (IIALDs)
HIV-associated lympho proliferative disorders
MM and cytokines
Myeloma cells express a spp receptor for IL-6, which is the major growth and survival factor for MM cells
IL-6 is produced by cells in the bone marrow micro-enviromenent
Therapeutic options for DLBCL
Chemo - R-CHOP
RT
R-CHOP
5 chemo drugs featuring rituxiumab, cyclophosphamide etc
What do myeloproliferative disorders all have in common
JAK-2 mutation
Features of all MPN
BM failure –> anaemia, thrombocytopenia, leucopenia
Hepatosplenomegaly
Spp sx of essential thrombocytheamia
Clotting tendency –> headache, chest pain, gangrene, ALI
Spp sx of polycytheamia vera
Plethoric rosacea and pruritus after a bath
Hyperviscosity —-> headache and dizziness
Gout
Sole/ palm during
Cause of isolated, prolonged APTT (prolonged APTT w/ normal PT)
Haemophilia
What causes a prolonged PT w/ an abnormal APTT
Warfarin
What causes both prolonged PT and APTT
DIC
epo in polycythaemia vera
Low - all ‘used up’
Clinical significance of neutropenia
Recurrent infection
Risk of neutropenic sepsis - life-threatening
Clinical significance of neutrophilia
Hypercoagulability
Clinical significance of lymphocytosis
If well, no treatment required
May be sign of CLL
Clinical significance of eosinophilia
Eosinophilic asthma
ITP
Immune thrombocytopenic purpura
What is immune thrombocytopenic purpura
Autoantibodies against the platelet membrane which sensitizies the platelet causing their premature removal out of the circulation
Sx of ITP
Spontaneous bleeding, easy bruising, epistaxis i.e. nosebleeds or menorrhagia
Mx of DIC
Focus on treating underlying cause
Resus via ABCDE
Ventilatory and haemodynamic support in ICU
Give FFP and cryoprecipitate as well as anticoagulant
Clotting screen in vWD
Normal PT
Prolonged APTT
Myeloid malignancies
AML and CML
MDS
Myeloproliferative neoplasms (ET/ PV/ MF)
Lymphoid malignancies
ALL and CLL
HL and NHL
MM
What do DIC and TTP have in common for blood film finding
Red cell fragments
Blood ix findings for DIC
Low platelets
Long PT/ APTT
Low fibrinogen
Clotting screen in TTP
Normal
Px of PV
Aquagenic pruritus
B sx
Headaches
Early satiety
What should pt’s w/ PV NOT do
Take Fe supplements
How do we monitor success of PV therapy
Repeat FBC - looking fir Hit to reduce to 0.45
What are the indications for hydroxycarbamide in PV therapy
Inadequate reduction in Hct
Thrombosis (increase in platelets)
Haemorrhage
How can tissue samples be performed for LN bx
Core bx
Excision bx
NOT fine needle aspirate
Potential side effects of chemo
Immunosuppression
Feel sick
GI upset
Hair loss
What procedures should be considered in men before commencing chemo
Sperm cryotherapy preservation
Features of meningococcal meningitis
Severe headache Photophobia O/E unwell Pyrexia Neck stiffness Petechiae
What investigations are required after a blood transfusion reaction
Repeat G&S on all samples + cross-match DAT on post transfusion sample Examine blood for bacterial contamination FBC & film Coag screen for DIC Renal + liver function tests
Px of ET
Asymptomatic Thrombosis Burning sensation hands and soles Cold peripheries Splenomegaly
Ann Arbor staging of lymphoma
Stage I - involvement of single nodal group
Stage II - involvement of 2/2+ nodal groups on same side of diaphragm
Stage III - involvement of nodal groups on both sides of the diaphragm
Stage IV - disseminated disease w/ involvement of extra-lymphatic organs
Complications of CLL
Anaemia
Hypogammaglobulinaemia —> recurrent infection
Warm AIHA (10-15% pts)
Richter’s transformation
Richter’s transformation
CLL cells enter LN and become high-grade, fast-growing, NHL
Poor prognostic factors for HL
Raised ESR
Lymphocyte depleted type
Anaemia