Haemotology Flashcards

1
Q

Where are the RBCs produced throughout life?

A

Yolk sac (1 month)
Liver (2-birth)
All bone marrow (1-10yrs)
Mainly axial marrow (vertebra/pelvis) (10-death)

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2
Q

3 important haematopoietic growth production?

A
G-CSF: 
- granulocyte colony stimulating factor
EPO: 
- erythropoietin produced in kidney
- if reduced, leads to hypoxia
TPO:
- thrombopoietin produced in liver 
- if reduced, leads to thrombocytopenia
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3
Q

Full blood count

A
I. RBC
1.  Hb concentration
2. Haemotocrit (ratio of red cell to total)
3. cell number (RBC)
4. cell size (mean cell volume, MCV)
A. microcytic <80fl (iron deficiency)
B. normocytic 80-100 fl 
C. macrocytic >100 fl (B12/folate deficiency) 
5. MHC/MCHC (amount of Hb/RBC) 

II. platelets

III. white blood cells (number &differentiation)

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4
Q

Reticulocyte count

  1. what is it?
  2. In a patient with anaemia:
    a. why would it increase?
    b. why would it decrease?
A
  • number of young, recently released from bone marrow RBC
    2. a. normal response: to replenish the loss due to haemolysis or bleeding
    2. b. there is a problem with bone marrow production of RBC
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5
Q

Peripheral blood film

what is it?

A

drop of blood under microscope assessed for

  • number
  • size
  • colour
  • morphology
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6
Q

Define:

  1. -cythaemia
  2. -cytosis
  3. -cytopenia, 2 things that can lead to this?
  4. reactive cause vs neoplastic
A
  1. increased number
  2. increased number
  3. reduced number
    - production impaired or survival (haemolysis, bleeding)
    - 3 common ones: Anaemia, thrombocytopenia, neutropenia
  4. reactive cause can be due to anything (inflam, infection, autoimmune, etc) but neoplastic
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7
Q

Reactive concitions describing increased number of blood cells in :
I. lymphoid
II. myeloid

A
I.  lymphoid 
- lymphocytosis 
- polycolonal gammaglobulinaemia:
=== normal kappa:lambada ratio
=== due to infection, inflammation, malignancy 

II. myeloid

  • thrombocytosis
  • neutrophilia
  • polycythaemia
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8
Q

Polycythaemia

  1. def
  2. various causes
A
  1. Increased Hb, raised Hct
  2. I. Relative
    - due to reduced plasma volume, no change in absolute RBC mass, proportionate increase
    - dehydration, diuretics, alcohol

II. absolute
IIa. Primary :
- ruba vera
- JAK2 mutated, EPO suppressed

IIb. Secondary:

  • hyoxia, smoking, altitude, tumours
  • JAK2 unmutated, EPO increased
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9
Q

Thrombocytosis causes

A
1. reactive
• Trauma (e.g. by surgeon)
• Infection
• Inflammation
• Non Haematological Malignancy
• Iron deficiency
• Splenectomy
  1. Clonal: Myeloproliferative disorders (MPN)
  2. Spurious (FBC machine counts something else as platelets)
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10
Q

Leukocytosis

A

Mainly neutrophilia and lymphocytosis

Common causes:
1. Reactive
• Trauma (e.g. by surgeon)
• Smoking
• Infection
• Inflammation
• Steroids
• Non haematological Malignancy
• Splenectomy
2. Clonal
(lymphoproliferative, myeloproliferative, acute or chronic)
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11
Q

Causes of lymphadonepathy

A
  • Infection (viral e.g. HIV/EBV , bacterial e.g TB)
  • Non haematological cancer (e.g. Ca)
  • Inflammatory (e.g. sarcoid, SLE)
  • Lymphoproliferative neoplasms
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12
Q

Symptoms of myeloma?

A
CRABI” acronym
C- Hypercalcaemia
R- Renal dysfunction
A- Anaemia
B- Bone – lytic lesions, fractures, osteoporosis
I- Infection
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13
Q

2 O/E signs of thrombocytopenia?

A
  1. petechiae (pin prick bruises)

2. Ecchymoses (wide spread bruises)

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14
Q

Neutropenia

  1. epi
  2. increased risk of ?
A
  1. africans have lower levels of neutrophils than others

2. bacterial infection (not parasite or viral infection)

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15
Q

2 types of Acute leukaemia?

A
  1. acute myeloid leukaemia (AML)

2. acute lymphoblastic leukaemia (ALL)

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16
Q

Leukaemia

  1. How it leads to anaemia/immune suppression?
  2. Sx
A
    • Clonal proliferation of malignant blood cells derived from primitive haemopoietic stem cells in bone marrow.
    • Uncontrolled expansion of hypofunctional cells in blood, bone marrow and other organs leads to suppression of normal haematopoiesis and immunity
  1. Main clinical problems include anaemia, bleeding and susceptibility to infection.
    - Also lymphadenopathy, hepatosplenomegaly, and skin and CNS infiltration
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17
Q

Leukaemia:

  1. Endogenous RFs
  2. Exogenous RFs
A
  1. Endogenous factors
    - Chromosome fragility syndromes
    - Downs syndrome
    - Hereditary immune deficiency
    - Familial
  2. Exogenous factors
    - Radiation
    - Chemotherapy
    - Benzene
    - Viral infection
    - Acquired immune deficiency
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18
Q

Acute Myeloblastic Leukaemia (AML)

  1. Epi?
  2. Ix
  3. Mx
  4. complication of treatment
A
  1. Commoner in adults, Incidence 1:10,000 annually, Increased frequency with age (median >70 yr)
2. 
I. FBC: 
- low Hb and platelet count
- WBC usually 20 – 100 x 109/L with blast cells visible on the peripheral blood film. 
- WBC >50 = high risk
II. Bone marrow: 
- blasts > 20% of nucleated cells
III. Flow cytometry: 
- CD13+, CD33+ helpful to confirm AML. 
IV. Cytogenetics: 
- good prognostics: 
------t(15;17), 
------t(8;21), 
------inv16 .
- poor prognostic markers: 
------Monosomy 7, 
------abnormalities on chromosome 5, 
------chromosome 1
------complex cytogenetics (>5 abnormalities)
  1. I. Combination chemotherapy
    - cytosine arabinoside
    - daunorubicin.
    - Retinoic acid/arsenic trioxide used in acute promyelocytic leukaemia.
    - High dose ara-C important in optimising outcome
    - 3-4 cycles of therapy given 4 – 6 weekly.
    - Treatment induces profound marrow suppression, prolonged pancytopenia
    II. Supportive care
    - Transfusion of red cells and platelets.
    - Antiseptic mouthwashes, clean diet, oral prophylactic anti-fungal agents and antibiotics.
4. 
• Infection: mainly bacterial and fungal
• Bleeding (if in CNS can be fatal)
• Debility, profound weight loss
• Social: inpatient for most of 6 months, loss of employment, stress on family

5.

  • Overall complete remission rate: 85%
  • Overall survival: 45-50% cured with chemotherapy alone
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19
Q

Acute Lymphoblastic Leukaemia (ALL)

  1. def
  2. age
  3. how to differentiate from AML?
  4. Ix?
  5. treatment
  6. prognosis
A
  1. Primitive lymphoblasts infiltrate bone marrow and circulate in blood, infiltrate liver and spleen
  2. peak age 2 – 10 years. Another peak >60 years
  3. Commonly causes severe bone pain, sweats
  4. As for AML.
    I. Lumbar puncture important to determine if there is evidence of CNS disease (usually done when peripheral blasts cleared)

II. Flow cytometry may show blasts of B cell (CD10+, CD19+) or T cell lineage (20%).

III. Cytogenetics:

  • Philadelphia chromosome t(9;22) seen in 20-25 % of adults. Poor prognostic marker but specific therapy with tyrosine kinase inhibitors.
  • Other poor prognostic lesions
  • —–t(4;11),
  • —–t(8;14) ,
  • —–hypodiploidy
  • —–complex cytogenetics
5. 
I. Chemotherapy with complex combinations of cytotoxic drugs eg 
- steroids, 
- vincristine, 
- daunorubicin, 
- asparaginase. 

Phases of therapy

a. Induction: 2 months. Remission induction
b. Consolidation: 4 months intensive chemotherapy and CNS prophylaxis.
c. Maintenance: 2 years less intense therapy; mainly oral cytotoxic drugs with IV pulses of VCR

  1. > 85% cure in childhood ALL
    50% cure rate in adults who have intensive treatment on national trials.
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20
Q

Minimum residual disease

A
  • Leukaemic clone can be identifed by DNA fingerprinting and accurately measured using Q PCR. Sensitive (1 in 10,000 cells or better)
  • Response to therapy after 2 cycles of therapy may override other pretreatment prognostic factors
  • MRD used to decide treatment in children and adults
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21
Q

Bone marrow transplant

How does it work?

Major complications?

A
  • Allows use of higher (3-10x standard) doses of chemotherapy or chemoradiotherapy, kill more leukaemic cells
  • The transplanted stem cells give the recipient a new immune system that includes T cells capable of recognising leukaemia cells and killing them via a graft versus leukaemia effect
Major complications
• Relapse
• Graft versus host disease
• Extramedullary toxicity
• Infection
• Rejection
• Long term: infertility, second cancers
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22
Q

Neutropenic Sepsis

  1. what is it?
  2. Sx?
  3. Ix
  4. Mx
A
  1. The most common medical emergency that results from the treatment of leukaemia and bone marrow transplantation

• T >38C or patient looks unwell: culture and start broad spectrum antibiotics within 1 hour
3.
I. Absolute neutrophil count <0.5, worse if <0.2 or actually 0
II. Peripheral and line cultures, possibly CXR, MSU. Look for foci of infection.
III. CRP helpful to monitor response, may not be elevated on day 1

  1. I. culture and start broad spectrum antibiotics within 1 hour
    II. Treat hypotension, organ dysfunction eg hypoxia.
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23
Q

Blood donations tested for?

A
ABO group
RhD type
HIV 1+2 antibodies
Hepatitis BsAg + PCR
Hepatitis C antibody and
RNA PCR
Syphilis antibody
HTLV antibody
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24
Q

Processing of blood donations?

A
  1. Leucocyte depletion
  2. centrifuged:
    - red cells
    - platelets
    - Plasma:
    ====Fresh frozen plasma
    ====cryoprecipitate
  3. Platelets sampled for
    bacterial testing
  4. Special processes (to
    order):
    - irradiation,
    - washing,
    - hyperconcentration
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25
Q

Red cells in blood donations

  1. shelf life?
  2. storage?
  3. how much time once out of fridge
  4. uses
A
  1. 35 day shelf life
  2. at 4 degrees
  3. transfuse < 4 h after removing from fridge
  4. Uses
    - Blood loss
    - Anaemia
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26
Q

Platelet concentrates in blood donations

  1. 2 methods of getting them?
  2. shelf time?
  3. storage
  4. uses?
A
1. 
I. Pool 4-6 donors blood
II. Apheresis
- single donor
2. max for 7 days
3. Storage: 22oC 
4. Uses: 
- Thrombocytopenia
-Bleeding with low plt
-Preventing bleeding
-very low plt
-before procedures
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27
Q

Fresh frozen component in blood donations

  1. storage
  2. shelf-time
  3. use
  4. special processing
A
  1. Plasma frozen to -30oC
  2. 2 yr storage
  3. For clotting factor replacement if bleeding
    4.
    I.Viral inactivation
    -Methylene Blue
    II. Solvent detergent
    treatment (Octaplas)
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28
Q

Cryoprecipitate

  1. how is it formed?
  2. use
A
  1. Precipitate that forms
    when thawing FFP
  2. Fibrinogen replacement
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29
Q

When to give blood transfusion in anaemia?

A

If below Hb < 7g/dL

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30
Q

acute haemolytic transfusion reaction
1. Time period?
2. types
3.

A
  1. at any time up to 24 hours following a
    transfusion
  2. I. haemolytic reactions,
    II. transfusion-related acute lung injury (TRALI),
    III. transfusion-associated circulatory overload (TACO),
    IV. transfusion-associated dyspnoea (TAD) V. those due to bacterial contamination of
    the component
  3. Fever, renal failure
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31
Q

Donor PLASMA compatibility: Platelets, FFP & cryoprecipitate

A

A receives from A or AB
B receives from B or AB
O receives from any
AB receives from AB

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32
Q

Blood clotting pathway (haemostasis)

A
  1. Collagen and tissue factor exposed
  2. Von Willebrand Factor binds collagen
  3. Platelets adhere to vWF-collagen
  4. Platelets activate and aggregate
  5. TF initiates rapid thrombin generation on activated platelets (by causing release of Proteases (FVII, FX, FIX, FXI) and Co-factors (FVIII and FV))
  6. Thrombin converts fibrinogen to fibrin and
    completes platelet activation
  7. Stable fibrin-platelet clot is formed
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33
Q

3 regulations of haemostasis

A
  1. vWF activity is regulated by ADAMTS 13
  2. Thrombin is regulated by Antithrombin and Activated protein C
  3. Fibrin cleaved by Plasmin into fibrin degradation products (D-dimer)
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34
Q

2 types of clinical disorders of haemostasis?

Compare their bleeding pattern?

Their main complication?

Timing of bleeds?

A
  1. Primary haemostasis disorders
    - defect: Platelets, VWF, vessel wall
    - mucocutaneous bleeding eg epistaxis, purpura
    - immediate bleeding
  2. Coagulation pathway disorders
    - defect: Coagulation factors and fibrinogen
    - deep tissue bleeding (joints)
    - delayed bleeding (weak clot forms and breaks, followed by secondary bleeding)
    Both can cause GI/CNS bleeds
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35
Q

Laboratory investigations of bleeding?

A
1. Platelet count + blood film
Indicates platelet number (not function)
2. Coagulation screen
I. Prothrombin time (PT)
II. Activated partial thromboplastin time (aPTT)
Indicate function of coagulation pathway
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36
Q

Principle of Prothrombin time (PT) and Activated partial thromboplastin time (aPTT)

What do each detect?

A
  1. Venous blood anticoagulated in 0.9% citrate to remove Calcium and stop clotting
  2. centrifuge plasma
  3. Add coagulation ‘activator’: includes calcium
  4. Incubate at 37 C
  5. Time to fibrin clot formation

PT:
• ‘Thromboplastin’ activator
• Detects abnormal FVII, (extrinsic pathway)
FX, FV, FII, Fibrinogen (common pathway)

aPTT
• ‘Contact activator’
• Detects abnormal FVIII, FIX, FXI (intrinsic factors)
FX, FV, FII, Fibrinogen (common pathway)

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37
Q

Haemophillia

  1. 2 types
  2. defects in
  3. genetics?
  4. Sx
  5. Mx
A
  1. A & B
  2. Defect in F8 gene causing reduced FVIII (haemophilia A)
    Defect in F9 gene causing reduced FIX (haemophilia B)
  3. Sex-linked recessive inheritance (on X chromosome)
  4. Coagulation pathway disorder
    I. Mild or severe bleeding depending on factor level
    II. Soft tissue and joint bleeds
    III. Life-threatening CNS or GI tract bleeds
    IV. Chronic arthropathy (bleeding in joint leads to inflammation)
    V. Treatment acquired HCV and HIV
    • Recombinant factor concentrate (synthetic factor 8 & 9)
    • prophylaxis every 2-3 weeks
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38
Q

Von Willebrand disease

  1. normal role of vwf?
  2. Mild and severe Sx?
  3. Ix?
  4. Mx
A
    • VWF mediates PLT adhesion to collagen
    • stabilises coagulation Factor VIII in the plasma
  1. MILD VWD:
    - Epistaxis, easy bruising and traumatic skin bleeding
    - Defective primary haemostasis
    SEVERE VWD:
    - Additional coagulation pathway
    - defect due to low FVIII
  2. I. First line tests
    • Platelet count normal
    • Long aPTT in moderate or severe VWD (when FVIII level is low)
    II. Second line tests
    • reduced plasma VWF activity
    • reduced plasma FVIII activity
  3. I. Tranexamic acid
    Reduces clot break-down (antifibrinolytic)
    II. DDAVP/Desmopressin
    - Releases endogenous FVIII and VWF
    - only works once, temporary release
    III. VWF/FVIII concentrate
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39
Q

Acquired bleeding disorders

A
1. Abnormal synthesis
• Liver disease*
• Vitamin K deficiency (coagulation factors II, VII, IX, X)
• Warfarin*
2. Abnormal function
• Heparin and direct acting oral anticoagulants*
• Renal failure (platelet dysfunction)
• Anti-platelet drugs
3. Dilution
• Massive transfusion
• Cardiopulmonary bypass
4. Consumption
• Disseminated intravascular coagulation*
• Thrombocytopenia in sepsis
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40
Q

Liver disease leading to bleeding disorders

  1. things that may be affected?
  2. Ix
  3. Mx
A
  1. I. ↓Synthesis of most clotting factors, fibrinogen and coagulation regulators
    II. ↓PLT number (hypersplenism) and PLT function
    III. Biliary obstruction gives vit K malabsorption
    (↓synthesis of Factors II, VII, IX and X)
    IV. Hyperfibrinolysis
  2. • increased PT and APTT, reduced PLT count
    • reduced Fibrinogen and all clotting factors
3. 
• Local measures (compress) 
• Endoscopy for variceal bleeding
• Tranexamic acid
• Vitamin K
• Vitamin K factor concentrate
• Fresh frozen plasma (if everything is missing)
• Fibrinogen concentrate
• Platelet transfusion
41
Q

Thrombotic microangiopathies

2 examples?

A
  • Acquired disorders of haemostasis
  • May have bleeding and thrombotic features
  • Multisystem disorders requiring emergency care
  1. Disseminated intravascular coagulation (DIC)
  2. Thrombotic thrombocytopenic purpura (TTP)
42
Q

Disseminated intravascular coagulation (DIC)

  1. causes?
  2. pathogenesis
  3. Ix
  4. Mx
A
1. 
I. Sepsis
II. Major trauma
III. Obstetric emergencies (pre-eclampsia,
amniotic fluid embolism, retained POC)
IV. Advanced malignancy
2. 
I. Pro-coagulant stimulus + loss of regulatory pathways --> Widespread activation of coagulation pathway 
II. Fibrin/platelet rich
microvascular thrombi and Multiorgan failure 
III. Platelet, fibrinogen and
coag factor consumption and bleeding
3. 
• PT and APTT increased
• Fibrinogen and PLT count decreased
• D dimer increased (marker of clots)
4. 
• Fresh frozen plasma
• Platelet transfusion
• Fibrinogen concentrate or
cryoprecipitate
43
Q

Thrombotic thrombocytopenic purpura

  1. sx
  2. cause
  3. pathogenesis
  4. Ix
  5. Mx
A
1. Often insidious onset fever, malaise, arthralgia
• Bleeding (from thrombocytopenia)
• Variable neurological features
 Headache
 Reduced consciousness
 Stroke
 Visual disturbance
• Chest pain
• Jaundice
• Pallor and fatigue
• Abdominal pain
2. 
Caused by anti-ADAMTS13 antibodies
3. anti-ADAMTS13 antibodies-> Reduced proteolysis of VWF -> Circulating ultra-high molecular weight VWF multimers -> Platelet agglutination in ‘high shear’ vessels, microvascular, thrombosis, platelet consumption, mechanical haemolysis
4. 
I. FBC: PLT reduced and Hb reduced 
II. Blood film is diagnostic (smashed in half)
III. LDH increased
IV. PT and APTT- N

(ADAMTS 13 level reduced)

5. 
I. PLASMA EXCHANGE
II. Supportive care
• RBC transfusion
• Aspirin and low molecular
weight heparin
• Immunosuppression
• Iv corticosteroids
Rituximab
44
Q

DVT

  1. first investigation?
  2. secondary Ix?
  3. sx?
  4. complication?
A
  1. Wells score for DVT diagnosis
  2. I. Score >1=
    - DVT likely
    - Doppler USS
    II. Score 1 or less:
    - DVT unlikely
    - D dimer test
    - Doppler USS if high
  3. • Unilateral pain, swelling,
    tenderness, redness.
    • Dilated superficial veins, venous
    gangrene very rare
  4. Post-thrombotic syndrome
    - Chronic swelling and aching
    Venous eczema and ulcers
    - managed by Elevation, compression
    stockings, skin care
45
Q

PE

  1. Sx
  2. Ix
  3. complication
A
1. 
• Dyspnoea, pleuritic chest pain,
haemoptysis
• Syncope, palpitations, collapse
(massive or sub-massive PE)
2. 
I. ECG- tachycardia, R heart strain
II. Blood gasses/sats- low O2
III. CXR- normal or wedge infarcts
IV. D-dimer- increased
V. CT pulmonary angiogram filling
defect
3. 
I. death
II. Chronic thromboembolic
pulmonary hypertension (CTPH)
• 0.5-5% of treated PEs
• Clots are replaced by fibrous tissue
• Progressive pulmonary
hypertension and R heart failure
46
Q

3 conditions that increase the risk of DVT?

A
  1. Antithrombin deficiency
    - MANAGEMENT
    —Resistance to heparin anticoagulation
    —Longterm anticoagulation, short term AT
    concentrate
  2. Factor V Leiden
    - Reduces inactivation of Factor V by activated protein C
  3. antiphospholipid syndrome
    - Some APL antibodies ‘activate’ vascular endothelial cells and platelets and are potently pro-thrombotic
    - MANAGEMENT:
    - If thrombotic, longterm anticoagulation (plus antiplatelet agent if arterial thrombosis)
    - Thromboprophylaxis improves pregnancy outcomes
47
Q

Management of DVT and PE?

I. Immediate
II. long-term

A

I. Immediate anticoagulation
- Fast acting anticoagulant minimum 3 months
- (Rivaroxaban or LMW heparin)
II. Long term anticoagulation
- Depends on individualised risk vs benefit
- Longterm if recurrent or on-going risk factor
- (Rivaroxaban, warfarin. LMWH in cancer or pregnancy)

48
Q

Anti-thrombotic drugs

A
  1. Anti-platelet drugs
    • Inhibit platelet activation or aggregation
    • eg. Aspirin, clopidogrel, abxiximab
    • Treatment/prevention arterial thrombosis (ACS, PVD, CVD)
  2. Anti-coagulant drugs
    • Inhibit coagulation pathway
    • Treatment/prevention venous thrombosis or low pressure vessel thrombosis (DVT, PE, CVA in AF and mechanical
    heart valves, Cardiopulmonary bypass, dialysis)
49
Q

NICE guidlines for VTE thromboprophylaxis

A
  1. All patients are assessed for risk of VTE and bleeding
  2. All patients at risk of VTE should:
    • Mobilise early
    • Receive pharmaceutical thromboprophylaxis (eg enoxaparin 40 mg once daily)
50
Q

Heparin

  1. mech of action
A
  1. • Increases activity of natural anticoagulant
    antithrombin
    • Inhibits active clotting factors esp. Factors IIa
    (thrombin) and Xa
51
Q

UF vs LMW heparin

  1. route
  2. metabolism
  3. half-life
  4. SE
  5. dosing
  6. reversal
A
  1. IV vs SC
  2. Complex, renal vs Predictable, renal
  3. 1-2 hours vs 4-6 hours
  4. Bleeding
  5. 5000 iu loading then 20 iu/kg/hr
    Monitor and adjust to APTT
    ratio 1.5-2.0

vs

I. Thromboprophylaxis: 40 mg
sc once per day
II. Treatment: 1.5 mg /kg once
per day

  1. Protamine iv 1mg/100 IU heparin in last hr (max 40mg)
52
Q

Rivaroxaban

  1. mech of function
  2. when used?
  3. half-life
  4. metabolism
  5. dosing
  6. reversal
A
  1. • Direct oral anticoagulant (DOAC)
    • Factor Xa inhibitor
    • Reduces thrombin generation
2. 
I. VTE prevention after knee/hip replacement
II. Stroke prevention in non-valvular AF
III. Acute treatment of DVT
IV. Long term prevention of DVT and PE
  1. Plasma half life 8 hours
  2. 75% liver metabolised, 25% renal excreted
  3. Typical dose 15 mg bd or 20mg od
  4. Specialist products (APCC, specific reversal agents) for severe bleeding
53
Q

Warfarin

  1. mech of action
  2. uses
  3. metabolism
  4. half-life
  5. dosing
  6. reversal
A
  1. Inhibits vitamin K metabolism
    • Vitamin K is needed for synthesis of
    clotting factors II, VII, IX and X
    • Reduces factor levels to 20-30%
  2. I. Anticoagulation when DOACs are unproven or unsafe
    • Mechanical heart valves
    • Antiphosphoilipid syndrome
    • Chronic kidney disease
    II. Long term management of VTE
    III. Stroke prevention in atrial fibrillation
    IV. With anti-platelet agent, to prevent arterial thrombosis
  3. Plasma half life ~36 hours
  4. Metabolised by liver
  5. Typical dose 2-8 mg od
  6. • Vitamin K1 1-3 mg po or iv if INR >8.0 for mild bleeding
    • Vitamin K factor concentrate (eg Octaplex) plus Vit K1 for severe bleeding
54
Q

Group & Save versus Crossmatch

A

I. Group and save [40 mins]

  • perform IAT screening and store sample
  • if antibody negative blood can be rapidly issued if needed
  • request this if blood might be needed but not inevitable.

II. “Crossmatch blood” [5-40 mins]

  • laboratory will assign units for specific patient
  • 5 minutes if recent group and save
  • 40 mins if antibodies/no previous G+S (IAT crossmatch)
55
Q

Haemolytic Transfusion Reactions:

I. Acute haemolytic transfusion reactions (AHTR)
1. def
2.confirmed by
II. Delayed haemolytic transfusion reactions (DHTR)
1. def
2.confirmed by

III. Transfusion-related acute lung injury (TRALI)
1. def
2. confirmed by
IV.

A

I.
1. are defined as fever and other symptoms/ signs of haemolysis within 24 hours of transfusion
2. confirmed by one or more of the following:
• a fall of Hb
• rise in lactate dehydrogenase (LDH)
• positive direct antiglobulin test (DAT)
• positive crossmatch.

II.
1. are defined as fever and other symptoms/ signs of haemolysis more than 24 hours after transfusion
2. confirmed by one or more of the following
• a fall in Hb or failure of increment
• rise in bilirubin
• incompatible crossmatch not detectable pre transfusion

III.
1. defined as acute dyspnoea with hypoxia and bilateral pulmonary infiltrates during or
within 6 hours of transfusion, not due to circulatory overload or other likely causes

2. Any 4 of the following within 6 hours of transfusion
• Acute respiratory distress
• Tachycardia
• Increased blood pressure
• Acute or worsening pulmonary oedema
• Evidence of positive fluid balance 

IV. transfusion-associated dyspnoea
- respiratory distress within 24 hours of
transfusion that does not meet the criteria for TRALI, transfusionassociated
circulatory overload (TACO) or allergic reaction.

56
Q

Iron overload

  1. what blood component mostly affected?
  2. which organs are in danger?
  3. resulted from
  4. mx
A
  1. IRON
    • 1 unit red cells contains ~250mg iron
    • Maximum iron excretion ~3mg/day
  2. Toxicity- heart / liver / pancreas / joints/ pituitary
  3. Regular transfusion (several years) -iron overload
  4. • minimise transfusion
    • long term iron chelation (desferrioxamine [s/c] or deferasirox /
    deferiprone [oral] )
57
Q

Transfusion associated circulatory overload (TACO)

  1. sx
  2. tx
  3. prevention
A
  1. raised pulse & BP at 15 mins
  2. Slow down the infusion and give frusemide.
  3. Prevention: Identify at risk patients.
    Give frusemide with transfusion
    1 unit at a time.
58
Q

Major haemorrhage

  1. def
  2. mx?
A
  1. def
    - 50% of total blood volume lost in less than 3 hours
    - Loss of more than one blood volume within 24 hours
    (around 70 mL/kg, >5 litres in a 70 kg adult)
    • Give Tranexamic acid if less than 3 hours (bollus 10 min followed by iv infusion over 8 hours)

If still bleeding:
Correction of Hypofibrinogenaemia
- Fresh frozen plasma (FFP) 4 units (about 15 mL/kg)
- Cryoprecipitate 2 five-unit pools

59
Q

Chronic Lymphocytic Leukaemia

  1. def
  2. median age
  3. diagnosis
  4. Tx
  5. prognosis
  6. associated problems
A
  1. Clonal B cell lymphocytosis of >5 x 109/l persisting for more than 3 months
  2. median age at diagnosis 72 years
3. 
Immunophenotyping: 
Looking at antigens on WBC
- If score >3, CLL. 
- If <3, likely other form of B cell
malignancies (eg mantle cell
lymphoma)

4.
I. CHEMOTHERAPY:
- GO-GO patient, aggressive chemotherapy, back to normal very quickly
- elderly, gentle oral chemotherapy

II. BTK INHIBITION:
- Ibrutinib: brutons tyrosine kinase inhibitor
Tyrosine kinase: switches on cellular cycle
- very expensive,

  1. 17p depletion on cytogenetics (mutation), poor diagnosis
6. 
Infection
• Low immunoglobulins
Auto-immune disorders
• Auto-immune haemolytic anaemia
• ITP
Richter’s transformation
• rare
Secondary malignancy
• Especially basal cell carcinomas
60
Q

Causes of raised WCC

A
  1. infection
  2. proliferative
  3. inflammation
  4. steroids
61
Q

Chronic myeloid leukaemia (CML)

  1. sx
  2. genetics
  3. tx
  4. monitoring?
  5. prognosis
A
1. 
Asymptomatic or 
Hypermetabolic state
• Weight loss
• Sweats
Leucostasis (due to high WBC, Weisses Blut) 
• Shortness of breath
• Priapism
Symptoms from splenomegaly
• Discomfort
• Early satiety
  1. translocation t(9,22); phaladelphia chromosome:
    Formation of Bcr-Abl:
    - Inhibition of apoptosis
    - Up-regulates cell cycle progression and
    differentiation
  2. Imatinib blocks formation of Bcr-Abl, improving the symptoms
  3. monitor Bcr-Abl level
  4. good nearly normal if treated
62
Q

Raised haemoglobin causes?

A
  1. EPO production
  2. COPD
  3. congenital heart disease in adults
  4. kidney cancer
63
Q

Causes of raised platelet count?

A
  1. splenectomy
  2. inflammation
  3. iron deficiency
  4. malignancy
64
Q

The Myeloproliferative neoplasms

  1. 3 types
  2. mutation
  3. mutation results in?
A
  1. I. Polycythaemia rubra vera
    II. Essential Thrombocythaemia
    III. Primary Myelofibrosis
  2. JAK2 mutation
  3. wild type only cayses proliferation when EPO binds
    Mutation: doesnt need epo binding, causes proliferation without it

4.

65
Q

Polycythaemia Vera vs Essential Thrombocythaemia

Both associated with risk of?

A
I. 
• Raised red cell mass (Hct
>0.52 males, >0.48 Females)
• Exclude hypoxia, excess
erythropoietin

II.
• Raised platelet count (>450
x 109 /l)
• Exclude reactive process, iron deficiency

:::

1) Increased risk of thrombosis
2) Transformation to Myelofibrosis / Acute myeloid leukaemia

66
Q

Management of Polycythaemia Vera

A

• Venesection to maintain the Hct to <0.45
• Aspirin 75 mg/d unless contraindicated
• Cytoreduction should be considered if:
–Poor tolerance of venesection;
–Symptomatic or progressive splenomegaly;
–Other evidence of disease progression, e.g. weight loss,
night sweats;
–Thrombocytosis.

67
Q

Myelofibrosis

  1. def
  2. sx
  3. cause
  4. prognosis
  5. tx
A
  1. Symptomatic anaemia
  2. Discomfort from
    splenomegaly
    • Hypermetabolic symptoms (weight loss,
    sweats)
  3. bone marrow becomes thickened (due to fibrin) so spleen starts producing RBC, and if spleen cant liver takes over
  4. depends on the score, but in high risk survival 1/2 years
  5. ruxolotinib: JAK2 inhibitor
68
Q

Non hodgkin lymphoma

  1. Sx
  2. blood test
  3. diagnosis
  4. staging scan
  5. Ann Arbor staging
  6. tx
A
1.
I. Enlarged Lymph nodes
II. B Symptoms
◦ Drenching Night sweats
◦ Unexplained Fevers >38’C
◦ Weight loss >10% in last 6 months
III. Other symptoms
◦ Fatigue
◦ Itching
◦ Symptoms related to cytopenias
  1.  Full Blood Count (FBC)
     Renal function (can it handle chemotherapy)
     Liver function (can it handle chemotherapy)
     LDH (raised, used as a marker)
     Calcium (raised)
3. 
 Lymph node biopsy
4. 
Staging scan:
- (CT Neck,Chest,Abdo,Pelvis or PET scan)
- Bone marrow biopsy
    • Stages 1-4 and tells you how many places you have lymphoma in:
      I. one place
      II. more than one on the same side of diaphragm
      III. both sides of diaphragm
      IV. exta lymphatic ( eg lungs)

A (absence of B sx) or B (presence of B sx)

6.
- Stage IA RCHOP x4 + Local Radiotherapy

- Stage IIA – IV RCHOP x 6-8cycles
RCHOP chemotherapy:
Rituximab – monoclonal antibody
Cyclophosphamide
Hydroxydaunorubicin chemotherapy
Oncovin
Prednisolone Steroids

Given every 3 weeks
Risk of neutropenic sepsis day 7-10

69
Q

RCHOP chemotherapy:

A
Rituximab – monoclonal antibody
Cyclophosphamide
Hydroxydaunorubicin chemotherapy
Oncovin
Prednisolone Steroids
  • Given every 3 weeks for non-hodgkin lymphoma
  • Risk of neutropenic sepsis day 7-10
70
Q

Types and treatment of low grade lymphoma

A
Types
◦ Follicular Lymphoma
◦ Marginal Zone Lymphoma
◦ (Mantle Cell Lymphoma)
◦ Small lymphocytic Lymphoma

Management
 Active monitoring
 Radiotherapy
 Chemotherapy/ Monoclonal Antibodies/ Targetted therapies

71
Q

Hodgkin lymphoma

  1. Treatment of
  2. Prognosis?
  3. late SE
A
  1. Treat with
    - ABVD +/- Radiotherapy
  2. > 85% 5 year survival*
  3. Late effects of treatment
    - Second malignancy eg Lung/Breast cancer
    - Heart or lung problems
72
Q

Myeloma

  1. def
  2. Ix
  3. Monoclonal gammapathy of underterimined significance (MGUS)
  4. smouldering myeloma
  5. Tx
A
  1. Cancer of plasma cells
    increased clonal plasma cells
    Monoclonal protein
  2.  Immunofixation of serum and urine
     Bone marrow biopsy: monoclonal paraprotein
3. 
 Serum monoclonal protein <30g/L
 Clonal bone marrow plasma cells <10%
 Absence of end-organ damage (have paraprotein of no significance)
 Active monitoring
  1. Serum monoclonal protein (IgG or IgA) ≥30g/L
     or urinary monoclonal protein ≥500mg per 24h
     and/or clonal bone marrow plasma cells 10-60%
     Absence of myeloma defining events or
    amyloidosis
  2. I. Vigorously rehydrate with at least 3 litres of normal saline daily
    II. Stop nephrotoxic drugs e.g. NSAIDs
    III. Administer high dose dexamethasone (sterioid, anti-myeloma effect)

6.

73
Q

Main complications of myeloma and how to manage?

A
I. hypercalcaemia, sx:
- CNS dysfunction - confusion, coma
- Muscle weakness
- Constipation
- Thirst, polyuria
- Shortening of the Q-T interval on ECG
Mx: 
Hydration with IV fluids 
\+ Bisphosphonates – zoledronic acid/
pamidronate
II. hyper viscosity syndrome: 
----->Presentation
◦ blurred vision
◦ headaches
◦ mucosal bleeding
◦ dyspnoea due to heart failure

Mx:

  • plasma exchange
  • isovolaemic venesection (if cant plasma exchange)

III. Spinal cord compression

Mx:
 Dexamethasone 40 mg daily for 4 days
 Urgent MRI whole spine
 Neurosurgical/spinal surgical review if bony lesion to decompress or stabilise spine
 Local radiotherapy - if non-bony lesions ASAP (within 24 hours)

74
Q

Myeloma treatment

A

I. Traditional Chemotherapy
◦ E.g. Cyclophosphamide, Melphalan
II. Steroids
◦ E.g. Dexamethasone

III. Immune modulatory drugs
◦ anti-angiogenic, anti-inflammatory, anti-proliferative effects
◦ E.g. thalidomide, lenalidomide

IV. Proteosome inhibitors
◦ involved in the removal, breakdown and recycling of damaged proteins or those
that are no longer needed by the cell. Proteosome inhibitors cause cell death
◦ E.g. bortezomib

V. Bisphosphonates
◦ Block the action of osteoclasts
◦ zoledronic acid, pamidronate

VI. thromboprophylaxis

75
Q

Anaemia causes

  1. microcytic
  2. normocytic
  3. macrocytic
A
1. 
I. Causes:
- Iron deficiency
- Thalassaemia
- Anaemia of chronic disorder
II. 
- Acute blood loss
- Haemolysis
- Anaemia of chronic disorder
- Bone marrow infiltration
- Combined haematinic deficiency
III. 
- B12/folate deficiency
- Haemolysis
- Hypothyroidism
- Liver disease
- Alcohol excess
- Myelodysplasia
76
Q

Effect of the following on the RBC

  1. age,
  2. gender,
  3. altitude,
  4. smoking behaviour
  5. stage of pregnancy
A
  1. ageing –> suppressed bone marrow
  2. male post puberty higher than female
  3. Hb rises with altitude
  4. increased Hb
  5. increased RBC, but more plasma so looks diluted,
77
Q

Iron Deficiency Anaemia

  1. clinical features
  2. blood test result
  3. causes of deficiency?
  4. where is iron absorbed?
A
  1. Clinical Features (if severe)
    - Angular stomatitis
    - Glossitis
    - Koilonychia
    - Pharyngeal and oesophogeal webs
  2. blood test
    - Microcytic hypochromic (pale) anaemia
    - Low serum ferritin (beware: acute phase protein)
    - Absent iron stores in bone marrow

3.
• Dietary (80% from meat, 20% from vegetables)
• Physiological (infancy, adolescence, pregnancy)
• Blood loss
• Malabsorption e.g. coeliac disease

  1. duodenum
78
Q

Anaemia of chronic disease

  1. def
  2. main consequence ?
  3. causes?
  4. mx?
A
  1. Depression of erythropoiesis
  2. Main defect is failure of transport of iron
    from RE system to developing red cells
3. 
• Chronic infection/inflammation
• Malignancy
• Uraemia
• Endocrine disorders
  1. • Correction of underlying cause
    • Erythropoietin (+ iron)
79
Q

Macrocytic vs megablastic RBC?

A
Macrocytic 
– red cells in peripheral blood
are large. 
_ Erythropoiesis may or may not be
megaloblastic.
Megaloblastic 
– red cell precursors are
abnormally large because of impaired DNA
synthesis. 
_ The cell continues to grow but
does not divide as it is incapable of
replicating DNA. 
_ RNA synthesis and translation not affected.
80
Q

Vitamin B12 deficiency

  1. what type of anaemia does it cause?
  2. where stored?
  3. where synthesised?
  4. where/how absorbed
  5. Causes of deficiency?
  6. Sx?
  7. Ix?
A
  1. Megaloblastic anaemia
  2. mainly in the liver.
  3. Synthesised by micro-organisms: only
    present naturally in animal produce.
  4. Absorption: combines with intrinsic factor secreted by gastric parietal cells and
    absorbed in terminal ileum.
5.
I. Dietary: veganism, rare
II. Intrinsic factor deficiency:
- Pernicious anaemia
- Gastrectomy
- Congenital
III. Intestinal malabsorption:
- Disease of terminal ileum e.g. Crohns
- Blind loops &amp; small bowel diverticulae
6. Clinical features
I. Anaemia
II. Jaundice
III. Glossitis
IV. Neurological deficit
  1. Laboratory features
    I. Anaemia, neutropaenia, thrombocytopaenia
    II. Low serum vitamin B12
    III. Antibodies against parietal cells or intrinsic factor
    IV. Megaloblastic change in bone marrow
    V. Features of haemolysis
  2. Mx
    I. Vitamin B12 replacement as IM injection most common – 3x per week for 2 weeks then maintenance phase.
    II. Oral folic acid replacement.
    Care: risk subacute combined degeneration of the cord (with permanent neurological
    sequelae) if folic acid replaced in absence of vitamin B12. Replace B before F!
81
Q

Folic acid deficiency

  1. what type of anaemia?
  2. source?
  3. where is it absorbed
  4. causes of deficiency?
  5. Sx
  6. diagnosis?
  7. mx
A
  1. Megaloblastic anaemia
  2. Dietary sources: green vegetables, liver,
    nuts, cereals.
  3. Absorbed in the jejenum
  4. • Dietary – common in elderly, poor diet related to alcohol misuse.
    • Increased utilisation – e.g. in pregnancy, malignancy, haematological disorders with
    rapid cell turnover.
    • Malabsorption e.g. coeliac disease.
    • Drugs e.g. anticonvulsants.
    • Excessive loss e.g. renal dialysis
  5. Similar to vitamin B12 deficiency but neurological problems do NOT occur
  6. Laboratory features
    - Peripheral blood and bone marrow features identical to vitamin B12 deficiency.
    - Diagnosis made by measuring low serum (and sometimes red cell) folate levels.
  7. I. Vitamin B12 replacement as IM injection most common – 3x per week for 2 weeks then maintenance phase.
    II. Oral folic acid replacement.
    Care: risk subacute combined degeneration of the cord (with permanent neurological
    sequelae) if folic acid replaced in absence of vitamin B12. Replace B before F!
82
Q

Haemolysis

  1. what is it?
  2. 2 types?
  3. compensation
A
  1. Reduced red cell survival (normal life span=120d)
  2. RBC breakdown can be:
    • intravascular (within the vessels, releasing free Hb)
    • extravascular (by reticulo-endothelial system)
  3. Erythroid expansion and increased production (up to 7 fold) may
    partly compensate
83
Q

Causes of Haemolytic Anaemia

  1. inherited type?
  2. acquired type?
A
  1. I. Membrane: HS, Hereditary spherocytosis (auto-dominant)

II. Enzymes:

  • Glucose 6 phosphate dehydrogenase deficiency (X linked)
  • Pyruvate kinase deficiency (autosomal recessive)

III. Haemoglobin: Sickle cell anaemia; Thalassaemia (autosomal recessive)

  1. I. Immune:
    a) Autoimmune (primary or secondary to lymphoproliferative, autoimmune disorders, infections, drugs)
    b) Alloimmune:
    - antibodies do not belong to the host
    - e.g. haemolytic disease of the newborn, or incompatible blood transfusion

II. Infections –many mechanisms

III. Drugs and chemicals –many mechanisms

IV. Mechanical:

  • MAHA (microangiopathic haemolytic anaemia): small vessels due to overactive endothelium, mechanical break down of red cells
  • prosthetic heart valves

V. Other rare types: e.g. Paroxysmal Nocturnal Haemoglobinuria

84
Q

Sx of Haemolytic Anaemia

A
  1. Anaemia
  2. Jaundice
  3. Splenomegaly
  4. Skeletal abnormalities (congenital forms)
  5. Gallstones (pigment stones suggests chronic
    haemolysis)
  6. Haemoglobinuria (denotes intravascular haemolysis), very dark urine
85
Q

Ix of haemolytic anaemia

A

I. Blood film is the most useful investigation
II. Coombs test is used to detect immune coating on RBC by Ig and complement. If positive it suggests immune cause

Interperation:
Increased RBC production
• Reticulocytosis, polychromasia
• May become folate deficient

Increased RBC destruction
• Increased indirect bilirubin (unconjugated)
• Increased LDH
• Absent haptoglobins
• Intravascular: haemoglobinaemia, haemoglobinuria, haemosiderinuria

86
Q

Thalassaemias

  1. cause
  2. 2 types
A
  1. I. Reduced or absent synthesis of one or more of the globin chains of adult hemoglobin.
    II. Imbalance in globin synthesis.
    • Alpha Thalassaemia
    • Beta Thalassaemia
87
Q

3 types pf Beta Thalassaemia

A
  1. Beta Thalassemia trait (carrier)
    - Asymptomatic, normal life span
  2. Beta Thalassemia intermedia
    - Variable phenotype and life span
  3. Beta Thalassemia major
    - No Beta globin and no HbA
    - Early death if untreated
88
Q

Β thalassaemia major

  1. what is it defined as?
  2. consequence of excess alpha chains
  3. long term leads to?
A
  1. Complete absence of HbA
    • Excess α chains accumulate and damage red cells
    • Ineffective erythropoiesis
    • Excessive RBCs Destruction
  2.  Iron Overload
     Extra-medullary hematopoiesis
89
Q

Sx of Beta thalassaemia major?

A
  1. Symptomatic anaemia in first few months of life.
  2. Jaundice
  3. Growth retardation failure to thrive.
  4. Medullary hyperplasiaBony
    abnormalities especially of the facial bones.
  5. Extra medullary haematopoesisEnlarged
    spleen and liver .
  6. Increased risk of thromboses
  7. Pulmonary hypertension & congestive heart failure
90
Q

Treatment of β Thalassaemia major

A
  1. Regular blood transfusions (Life long):
    Transfusions 2 aims: prevent symptomatic anaemia, Also, suppress marrow hyperplasia with skeletal consequences.

(However, with transfusions come the inevitable problem of iron overload
(currently the life limiting factor) esp heart, liver, endocrine.)

  1. Iron chelation e.g. Desferrioxamine, Deferiprone, Deferasirox
  2. Folic acid
  3. Bone marrow transplantation in early life
91
Q

ALPHA THALASSEMIA

  1. def
  2. 3 types
A
    • deficient/absent alpha subunits
    • Excess beta subunits
    • Excess gamma subunits newborns
  1. (Silent Carrier: 1 gene not working)
    I. Trait: 2 genes not working
    II. Hemoglobin H Disease: 3 genes not working
    III. Major (Hemoglobin Bart’s): ALL 4 not working
92
Q

Hemoglobin H (HbH) Disease thalasasemia

  1. what is the defect
  2. sx
  3. mx
A
  1. reduced alpha chains (3 out of 4)
  2. jaundice, hepatosplenomegaly, leg ulcers, gallstones
  3. folic acid, transfusions, splenectomy
93
Q

Hb Barts hydrops

  1. def?
  2. consequence?
A
  1. no alpha chains produced, Mainly gammma chains

2. Intrauterine death and stillborn

94
Q

Normal Vs. Sickle Red Cells

A
Normal:
• Disc-Shaped
• Deformable
• Life span of 120 days
Sickle:
• Sickle-Shaped
• Rigid
• Lives for 20 days or
less
95
Q

3 things that happen as a result of sickle cell anaemia?

A
  1. Haemolysis
    • increased reticulocytes, sickle cells , target cells and hyposplenic changes
    • usually well-adjusted to anaemia: HbS has reduced oxygen affinity
    • red cells contain  80% HbS (remainder HbF)
  2. Vaso-occlusion
    • acute episodes of bone pain, worsening anaemia, pulmonary and neurological complications
    • Precipitated by cold, dehydration, infection
  3. Hyposplenism and risk of infection with encapsulated bacteria
96
Q

HbSS (sickle cell anaemia) emergency?

  1. Which conditions more likely?
  2. What condition more likely to affect children and elderly?
  3. What condition more likely to affect 20-29 yo?
  4. mx
A
  1. Acute chest syndrome, PE, infection, opiod excess
  2. Ischaemic: more common in children and older adults, and lowest in
    adults aged 20 to 29 years
  3. Haemorrhagic: most frequent in the 20- to 29-year age group
  4. Urgent neuroimaging, exchange transfusion to lower HbS %.
97
Q

Acute chest syndrome

sx?
mx?

A

Sx:
Fever, respiratory symptoms, new infiltrate on CXR

mx:
Patients need O2, IV fluid, antibiotics, incentive spirometry, analgesia and
reduction of HbS% by transfusion.

98
Q

Sickle cell trait (HbAS)

A
  • Usually asymptomatic

- Inability to concentrate urine (Occasionally renal papilliary necrosis)

99
Q

Sickle cell solubility test

A

The sickle cell solubility test relies on the relative insolubility of HbS in concentrated phosphate buffers compared to Hb A
and other Hb variants.
- Hb S precipitates causing a cloudy solution