Dunedin- Haematology Flashcards
Describe anticoagulation and their targets
How to manage elevated INR in adult patients
Describe NOAC, there target, and potent drug interactions
Describe the effect of anticoagulation on PT and aPTT
rivaroxoban increases PT alot
Describe warfarin bridging before surgery:
*stop warfarin 5 days prior to surgery
*4 days prior check INR and start enoxaparen when INR is <2
*cease enoxaparen 24 hours before procedure
What is acquired haemophilia A?
-Development of a clotting factor deficiency that was not present at birth
- usually due to an autoantibody to factor VIII
- usually present with significant bleeding into skin, muscles, soft tissues and mucous membranes
Lab
- prolonged APTT which does not correct with mixing study
- low level of factor VIII + inhibitor present
What is the management of acquired factor VIII inhibitors?
*recombinant activated Factor VII
*activated prothrombin complex concentrates (FEIBA-factor VIII inhibitor bypassing activity)
Immunosuppression: cyclophosphamide, rituximab, IVIG
What is the MOA of tranxemic acid?
Binds to plasminogen and prevents the breakdown of fibrin
Management of cerebral vein thrombosis, splanchnic vein thrombosis
Cerebral vein thrombosis –> 3-6 months unless unprovoked in which case 6-12 months
What is the MOA, eg and S/E of alkylating agents
Prevent cell division cross- linking strands of DNA–> prevent DNA synthesis–> programmed cell death
eg chlorambucil, cyclophosphamide, melphalan
S/E bone marrow depression, nausea and vomiting, late cancer
What is the MOA, e.g, S/E of antimetabolites
MOA: mimic normal cell components (in S phase) –>inhibit DNA replication
E.g folate methotrexate, pyrimidine: cytarabine
S/E: mucositis, bone marrow suppression
What is the MOA, e.g, S/E of anthracyclines
MOA: Many: free-radical formation, lipid peroxidation, direct membrane effects, enzyme interactions
Examples:
* Daunarubicin, Idarubicin,
doxorubicin
Side effects:
* Cardiotoxicity,
myelosuppression, alopecia
What is the MOA, e.g, S/E of topoisomerase II inhibitor
MOA: inhibits enzyme that manages the coiling of DNA –> accumulation
E.g. etoposide
S/E: diarrhoea, mucosal, nausea
What is the MOA of mitotic inhibitors, e.g, S/E
Mechanism: blocks microtubule formation –> prevents formation of mitotic spindle
E.g Vincristine
S/E: neurotoxicity, myelosuppression
What is the MOA, E.g, S/E of BCL inhibitor
MOA: BCL-2 proteins are pro- an anti- apoptotic proteins that, in
cancer cells, are over expressed
E.g. Venetoclax
S/E TLS, neutropenia
What is the MOA, E.g S/E of PL3K inhibitors?
MOA: PI3K/AKT/mTOR pathway is part of a signalling pathway for growth control, metabolism, translation initiation
Eg: idalalisib
S/E Autoimmune dysfunction, skin
toxicity, hypertension,
hyperglycaemia
What is the MOA of TKI inhibitors
Dont need mutation for it to work
Mechanism: Binds to BCR-ABL1 of oncoprotein BCR- ABL1
Examples: Imatanib, dasatinib, Nilotinib
S/E Hypertension,
diarrheoa, LV
dysfunction, QT
prolongation
What is the MOA of proteasome inhibitors?
MOA: Proteosomes are structures
in cells that remove mis-
folded proteins and destroy
them. Blocking this causes
cell death
Examples: Bortezomib
S/E Peripheral neuropathy, Nausea, vomitting
Describe the MOA of monoclonal antibodies
MOA- cross-linking surface antigen –> cell death
Describe the lab results of Tumour Lysis syndrome
*Increased uric
acid
*Increased
potassium
*Increased
phosphate
*Decreased
calcium
What is the management of TLS
hydration
allopurinol –> reduces formation of new uric acid
Rasburicase –> converts uric acid to allantoin (readily excreted), rapidly decreases uric acid. therefore can deal with uric acid that is already formed
What are the most common indications for stem cell transplant
Autologous:
Multiple myeloma, non-hodgkins lymphoma, Hodgkins lymphoma
Allogenic
- AML, ALL, myelodysplastic syndrome, non-hodgkin lymphoma, Myeloproliferative neoplasms, severe aplastic anaemia
- BM failure, immunodeficiency (SCID), autoimmune disease, bone marrow disorders (haemoglobinopathies, thalassaemias, haemophilia)
What problems arise if there is an issue with matching donor and recipient
if donor cells attack body –> GVHD
if host cells attack donor cell –> graft rejection
MHC 1 and 2
Class 1:
- HLA-A, B-, C
- present on ALL cells
Class 2:
-HLA-DR, DQ, and DP, DM DO
- only on immune antigen presenting cells e.g dendritic cells, b cells, monocytes
Describe complications of allogenic transplant
What is CAR-T cell therapy?
Chimeric antigen receptor T cell
take patients T-cells and re-program them and then give it back
What are indications for CAR-T cell therapy
1) Relapsed refractory acute lymphoblastic leukaemia (ALL)
2) relapsed/refractory (R/R) DLBCL after failure of at least 2 prior line of therapy
3) R/R mantle cell lymphoma, after failure of therapy with a Bruton’s tyrosine kinase (BTK) inhibitor
What are complications of CAR-T cell therapy?
Cytokine release syndrome (treatment symptomatic, tociluzimab, dexamethasone, methylprednisone)
- high fever and chills
- dyspnoea
- severe N/V and/or diarrhoea
- feeling dizzy or lightheaded
- headaches
- tachycardia
- fatigue
- muscle and/or joint pain
Neurotoxicity (dexamethasone, methylprednisone)
- headache
- confusion/agitation
- seizures
- dysphagia
- loss of balance
Describe pathogenesis of cytokine storm
What is the most common lymphoma? and how is it managed
diffuse large B cell lymphoma
biopsy: mixture of large and small cells in a diffuse pattern with loss of architecture
treatment: R-CHOP
- rituximab
- cyclophosphamide
- doxorubicin (hydroxydaunorubicin)
- vincristine (oncovin)
- prednisone
+/- radiotherapy
What are examples of myeloproliferative neoplasms and lab studies
- polycythaemia vera
- essential thrombocytosis
- myelofibrosis
- CML
PLETHORA
Lab studies:
- BCR:ABL for CML
- JAK2, Cal-R, MPL
Biopsy: hypercellular, fibrosis on reticulin stain
Myeloproliferative disease management?
CML –> TKI e.g imatinib, hydroxyurea
Polycythaemia –> phlebotomy, hydroxyurea
Essentail thrombocytosis –> hydroxyurea
Myelofibrosis
- JAK1/JAK2 –> ruxolitinib
- allogenic bone marrow transplant
CLL investigations
*FBC: smudge/ smear cells
*Flow cytometry: dim surface immunoglobulin, CD5, CD19, CD20, and CD23
*FISH: del(13q14), del (11a), and del (17p)
CLL treatment
1) watch and wait
2) treat if anaemia or thrombocytopenia, painful lymphadenopathy, B symptoms, lymphocyte doubling time, autoimmune haemolytic anaemia or ITP
What are indications of treatment of multiple myeloma
Indications for treatment
* >60% plasma cells
* Serum free light chains >100
*MRI lesions >5mm
* Hypercalcaemia
*Renal failure
* Anaemia
*Lytic lesions
Multiple myeloma treatment
Chemotherapy: bortezomib plus cyclophosphamide plus dexamethasone (VCD); bortezomib plus ow doxorubicin plus dexamethasone (PAD); and vincristine plus doxorubicin plus dexamethasone (VAD).
Non-chemotherapy regimens: Thalidomide/lenalidomide and dexamethasone, carfilzomib/bortezomib; daratumumab
Autologous stem cell transplant
What are aeur rods seen in?
AML particularly APML
Genetic abnormalities in AML
*t(8;21)(q22;q22),
* inv(16)(p13;q22),
* t(16;16)(p13;q22)
Describe the treatment approach for myelodysplastic syndrome
What are investigations for follicular lymphoma
Biopsy:
* Nodular growth pattern
* Amount of centroblasts determine tumour grade
* Staining:, CD20 (or CD19), CD10, and BCL-6 and are negative for CD5 and CD23, BCL-2 (>85%)
Molecular genetics: genetics: t(14;18)
What is the clinical presentation of follicular lymphoma
- painful adenopathy
- may grow spontaneously grown and regress
-usually asymptomatic otherwise
What is the treatment for follicular lymphoma?
No standard treatment
* Involved regional radiotherapy –
especially if stage I or II disease
* Anti – CD 20: rituximab; Obinutuzumab plus chemotherapy
What are causes of microcytosis
TAILS
Thalassaemia
Anaemia of chronic disease
iron deficiency anaemia
Lead posioning
Sideroblastic anaemia
What does transfused iron deficiency look like on a film?
central pallor
Describe anaemia of inflammation pathogenesis
infection/inflammation –> IL-6 –> increase hepcidin –> blocks ferroportin gate –> decreases Fe absorption in the gut, in the macrophages causes sequestration of Fe, therefore iron unavailable for Hb synthesis –> microcytic anaemia (functional iron deficiency)
What does lead toxicity look like on a blood film?
Prominent basophilic stippling
Regarding thalassaemia, what chromosomes are involved?
Alpha chains are from chromosome 16
Beta, gamma and other are chromosome 11
Describe alpha thalassaemia
Describe the clinical features of beta thalassaemia
*dependent on blood transfusions by definition
*expanded bone marrow, bone deformities
*hypersplenism
* hypercoagulable (VTE and cerebral)
*Iron overload –> cardiac failure and arrhythmias, delayed growth and puberty, chelation therapy (deferoxamine, deferiprone, deferasirox)
Describe some thalassaemia combinations and ones that are better and worse
Better –> alpha and beta thalassaemia
Worse –> B Thal + HbE, HbS+Bthal worsens sickle train
What does a blood film of B12/folate deficiency look like?
oval macrocyte, hypersegmented neutrophil, small RBCs (disordered erythopoiesis
What are some causes of macrocytosis
*Excess alcohol
*liver disease
*myelodysplastic syndrome (including sideroblastic)
*B12/folate deficiency
Drugs: phenytoin, cytotoxic, anti-virals, trimethoprim
Reticulocytosis: haemolytic anaemia, bleeding
Myeloma (25% of cases), haemochromatosis, smoking
Aplastic anaemia
What are causes of normocytic anaemia?
ABCD
A- acute blood loss
B- bone marrow failure
C- chronic disease
D- destruction (haemolysis)
What is more common, extravascular or intravascular haemolysis?
Extravascular is more common (just means splenic haemolysis)
What are causes of intravascular haemolysis?
*complement- mediated in paroxysmal nocturnal haemoglobinuria
*microangiopathic
*Heart values
What do we expect to see in Autoimmune haemolytic anaemia?
this is IgG antibody mediated
Anaemia
reticulocytes
bilirubin (unconjugated)
Low haptoglobin
direct antiglobulin test (DAT; aka Coombs)
Pathogenesis: macrophages removing membrane from RBCs resulting in spherocytes
What are Howell Jolly bodies?
These are basophilic nuclear remnants that occur post-splenectomy.
Other cells you can see post-splenectomy are target cells, spherocytes, odd cells
What are causes of acquired hyposplenism?
1) infarction (sickle cell, essential thrombocythaemia, polycythaemia vera)
2) Atrophy/hypofunction: coeliac, dermatitis herpetiformis, IBD, autoimmune (SLE, RA, GN, PBC, Sjogren’s MCTD, thyroiditis), irradiation
- bone marrow transplantation & GVHD
- HIV/AIDS
3) Infiltration: amyloid, sarcoidosis, leukaemia, myeloproliferative
What is the pathogenesis behind hereditary spherocytosis? And the mode of inheritance?
Mode of inheritance: Autosomal dominant
Occurs due to mutation sin Band 3, ankyrin, spectrin, and protein 4.2 –> this results in reduced surface-to-volume ratio –> reduced cellular deformability –> splenic destruction, anaemia
Describe the genetics of G6PD, and what it looks like on a blood film
one the X-chromosome (affects males more)
Fava beans
Bite cells/keratocytes
What are complications with hereditary spherocytosis?
*Cells trapped in spleen
*Anaemia
*life long excessive breakdown of haemologbin
*Pigment gallstones
splenectomy may be needed for cases with symptomatic anaemia
Describe the pathophysiology of G6PD deficiency
Describe some causes of drug-induced oxidative haemolysis
Dapsone
Sulphonamides
antimalarials
co-trimoxazole
naphthalene
What are some images of toxic neutrophils
What are causes of cold agglutinins?
IgM mediated
causes:
EBV, mycoplasma, lymphoma, DAT positive for C3d
most with cold agglutinin don’t have haemolytic anaemia but some do
Describe the different forms of laboratory diagnostics we have for lymphoma
1) morphology of a lymph node, at times blood, spleen, marrow, skin
2) immunophenotyping (immunohistochemistry and/or flow cytometry)
3) FISH/cytogenetics occasionally
Describe key blood film findings in different lymphoma
CLL –> smear/smudge cells
Peripheral T cell lymphoma –> the cleft and cerebriform cells of sezary syndrome/ peripheral T cell lymphoma
starry sky of burrito lymphoma
owl eye- Hodgkin lymphoma
Describe the different cell surface markers
B cells –> CD19, CD20, either kappa or lambda
T cells –> CD3, CD4, CD5, CD8
Stem cells (e.g. leukaemia blasts) –> CD34
Granulocytes –> CD33, CD13, CD15
Monocytes –> CD14, CD64
Describe abnormalities of von willebrand factor
VWF excess: TTP, HUS
VWF deficiency:
- genetic: von willebrand disease
- acquired: von willebrand syndrome (aortic stenosis and LV assist devices, essential thrombocythaemia, immune mediated, malignancy, hypothyroidism)
Where are VWF secreted from?
Secreted from endothelial cells (Weibel-Palade bodies) in an ultra-large form
After secretion ultra-large multimeters are cleaved by ADAMT312 (a disintegrin and metalloproteinase with thrombospondin type 1 motif, member 12)
failure to cleave leads to sticky WVF –> TTP
Describe the pathophys behind TTP
Usually due to a transient, low level acquired autoantibody against ADAMTs13 (<10%)
Excessively long VWF multimers bind platelets, which activate clotting. Red cells are then fragmented by fibrin strands leading to microangiopathic haemolysis
What is the treatment for TTP?
plasma exchange to replace the ADAMTs13 and to remove antibodies
What is the relation of shiga toxin and HUS?
Shiga toxin binds the Gb3 receptor (more abundant in kidneys and in children) leading to endothelial injury
usually develop symptoms 2-14 days after onset of blood diarrhoea and severe crampy abdominal pain, accompanies by nausea and vomiting
What is the different types of wVF disease?
Type 1- reduced LEVEL of VWF protein
Type 2- reduced function (activity <70% of expected for protein level)
Type 3- very low levels (both alleles affected)
What are some functional tests for WVF?
1) VWF activity assay (VWF: GP1bM)- GP1b binding; replacing RCoF
2) Ristocetin co-factor activity (VWF: Rio)
3) Collagen binding assay (VWF: CB)
4) Factor VIII levels
Lupus anticoagulant
How to test for anti-cardiolipin and anti-b-2 glycoprotein 1
via enzyme immunoassay (EIA=ELISA)
Anticoagulation of choice in anti-phospholipid syndrome?
warfarin
Describe the 4T score for HITS
1) thrombocytopenia: drop >50%
2) timing of platelet count: on day 5-10 following heparin
3) thrombosis or other sequelae
4) no other cause of thrombocytopenia
What chromosome is related to Haemophilia A and B?
X-chromosome
Describe the severity of haemophilia A and B
severe <1 IU/dL (<1% of normal)
Moderate 1-5 IU/dL (ie. 1-5% of normal)
Mild 5-40 IU/dL (ie. 5-40% of normal)
Describe the genetics of haemophilia A
Factor VIII
Most common defect: inversion of intron 22 in 40-45% of severe patients
Point mutations account for 67% of molecular defects, and small insertions and deletion represent 25%
What is Emicizumab?
For haemophilia A
a bispecific antibody that mimics FVIII activity by binding to both activated-FIX & X, thereby activating FX (remember that FVIIIa is a co- factor for FIXa
Used for “severe” (<2%) haemophilia A
What are some bypass agents in Haemophilia A
Activated prothrombin complex concentrate (aPCC) AKA FEIBA (contains factor 2, 7a, 9, and FX)
Bypass agents 2- recombinant F7A
What is immune tolerance induction in Haemophilia A?
~30% of severe haemophilia A develop inhibitors (allo- antibodies), usually within the first 20-30 days
Immune tolerance induction is used to eradicate inhibitors and involves frequent injections of concentrates over many months
What factor is involved in haemophilia B?
Factor 9
What cells are involved in HLH?
Macrophages
Natural killer cells and cytotoxic lymphocytes
cytokine storm
What most true about Factor VII?
A) deficiency typically prolonged APTT
B) FVIIa binds tissue factor
C) is a co-factor for factor VIII
D) acts as an anticoagulant
E) deficiency can be replaced with emicizumab
B) FVIIa binds tissue factor
What is the MOA of Eltrombopag?
thrombopoietin-receptor-agonist
Which of the following statements is true?
1.The pathological target of antiphospholipid antibodies is cardiolipin
- 80% correction in a 1:1 coag mixing study is suggestive of an antiphospholipid antibody
3.Correction of an APTT following addition of excess phospholipid is suggestive of a lupus anticoagulant
- Lupus anticoagulants are associated with bleeding
3.Correction of an APTT following addition of excess phospholipid is suggestive of a lupus anticoagulant
A 16-year-old patient presents with mild jaundice, fatigue, and a family history of haemolytic anaemia. Blood tests reveal the following: haemoglobin 125 g/L, mean corpuscular volume (MCV) 85 fL, and reticulocyte count 5%. Examination of the peripheral blood smear is performed.
Which of the following findings is most characteristic of hereditary spherocytosis?
A) Target cells on peripheral smear
B) Positive direct antiglobulin test (DAT)
C) Elevated mean corpuscular hemoglobin concentration (MCHC)
D) Decreased osmotic fragility
C) Elevated mean corpuscular hemoglobin concentration (MCHC)
Warm haemolytic anaemia vs cold
Warm- IgG
Cold- IgM
What is chromosome 5q deletion associated with?
myelodysplastic syndrome
mx lenalidomide
Describe the severity of haemophilia. Also the treatment
severe: 0-1%
moderate 1-5%
mild 5-30%
in mild-moderate haemophilia A, can give DDAVP peri-operatively
otherwise can give factor VIII
In a patient with Budd Chiari syndrome, the most common underlying myeloproliferative disorder is:
A. CML
B. Chronic myelomonocytic leukaemia
C. Myelofibrosis
D. Essential Thrombocythaemia
E. Polycythaemia vera
E. Polycythaemia vera
PNH piga gene affects what protein?
A. glycosylphosphatidyl-inositol
B. CD59
C. CD19
A. glycosylphosphatidyl-inositol
Regarding AML, which genetic abnormalities are favourable?
B- NPM-1
Which of the following is the most sensitive test of rivaroxaban activity?
A) APTT
B) PT
C) Prothrombinase complex
D) Prothrombin products
E) INR
B- PT
note: apixaban is Xa levels, rivaroxoban is PT levels, dabigatran is thrombin time
