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Section 1
Fluid and Haemodynamics (no answers)
1) Systemic thromboemboli:
a) 60% arise from intracardiac thrombib) 25% are of unknown originc) 75% of arteriolar embolisation are in the lower limbsd) 20% of arteriolar embolisation are in the braine) paradoxical emboli may enter pulmonary circulation
2) Stroke cascade in sepsis is:
a) LPS TNF IL6/8 ILIb) TNF LPS ILI IL6/8c) LPS ILI IL6/8 TNFd) LPS TNF ILI IL6/8e) ILI LPS TNF IL6/8
3) All the following are important leucocyte adhesion molecules EXCEPT:
a) ICAM Ib) VCAM Ic) LTB 4d) P-selectine) E-selectin
4) In acute inflammation:
a) mean capillary pressure is reduced by arteriolar dilation and opening of capillary bedsb) there is accumulation of extravascular fluid with specific gravity > 0.012c) neutrophils usually predominate for the first 48 hours d) phagocytosis may cause tissue damagee) in viral infections, monocytes are the first cells to arrive
Section 2
Haemostasis, Thrombosis & Haemorrhage
1) Regarding tissue factor/tissue thromboplastin:
a) its production by endothelial cells can be induced by IL-1 and TNFb) its production by endothelial cells can be induced by bacterial exotoxinc) it activates the extrinsic clotting systemd) it activates factor VIIe) all of the above are true
2) With regard to haemostasis, all of the following are true EXCEPT:
a) von Willebrands factor acts as a molecular bridge between platelets and collagenb) platelets bind von Willebrands factor via a glycoprotein receptor Go IIb/IIIa complexc) activated platelets bind to each other using fibrinogen as bridge moleculesd) platelet adhesion results in release reaction and exposes surface binding sitese) activated platelets accelerate activation of prothrombin 20,000 fold
3) Major sites of lodgement of systemic emboli include all of the following EXCEPT:
a) brainb) lower limbsc) coronary vesselsd) renal vesselse) spleen
4) Which is not an anti-coagulant?
a) thrombomodulinb) protein Cc) protein Sd) anti-thrombin IHe) thromboplastin
5) Which of the following is contained in the cytoplasmic granules of platelets?
a) ADPb) thrombinc) von Willebrands factord) P-selectine) glycoprotein receptor Gp 16
6) Functional deficiencies of all of the following prolong INR EXCEPT:
a) fibrinogenb) factor Vc) factor VIId) factor Xe) factor IX
7) Regarding protein C, all of the following are true EXCEPT:
a) it inactivates factors Va and VIIIab) it is a vitamin K dependent on plasma proteinc) it uses protein S as a co-factord) it is activated by the thrombomodulin-thrombin complexe) it stimulates conversion of plasminogen to plasmin
8) All of these factor sites of origin pairs are true EXCEPT:
a) thromboxane is formed by activated plateletsb) protein S is synthesised by endothelial cellsc) prostacyclin is elaborated by plateletsd) endothelial cells synthesise and secrete von Willebrands factore) fibrin stabilising factor is released from platelets
9) The activation of protein C:
a) is inhibited by endothelial cellsb) may cause intrinsic coagulation pathway inhibitionc) increases the activity of anti-thrombin Md) is not affected by warfarin administratione) stimulates the platelet secretion-release reaction
10) All of the following is released by activated platelets EXCEPT:
a) ADPb) prostacyclinc) factor Vad) serotonine) ionised calcium
11) Prostacyclin (PGI2):
a) is formed by the action of lipo-oxygenase on arachidonic acidb) is liberated by activated plateletsc) is liberated by vascular endothelial cellsd) enhances platelet aggregatione) enhances thrombomodulin activity
12) Regarding the clotting pathways, all of the following are true EXCEPT:
a) a prolonged APT indicates a defect in the intrinsic pathwayb) the intrinsic pathway is more important in vivo than the extrinsic pathwayc) the extrinsic pathway is initiated by tissue factor acting on factor VIId) factor X is common to both pathwayse) deficiency of factor XII does NOT cause a bleeding tendency
13) Regarding platelets, all of the following are true EXCEPT:
a) they do not have nuclei and cannot reproduceb) they contain actin, myosin and tropomyosin in the cytoplasm, which are all contractile
proteinsc) they are coated with glycoproteins that cause them to avoid adherence to normal
endotheliumd) contain alpha granules which are rich in ADP and Ca++
e) form thromboxane helping platelet aggregation
14) Factor VIIa:
a) is a component of the extrinsic clotting pathwayb) directly activates factor IXc) is inhibited by protein Cd) its deficiency results in von Willebrands diseasee) is dependent on vitamin K for its synthesis
15) The mechanisms of thrombin involvement in thrombosis include all the following EXCEPT:
a) increased P-selectin presentation on endothelial surfacesb) conversion of prothrombin to thrombinc) factor V and VII activation d) decreased mast cell heparin releasee) increased platelet aggregation
16) With regard to haemostasis, all of the following are correct EXCEPT:
a) activated protein C degrades factors Va and VIIIab) protein C is activated by thrombin in the presence of thrombomodulinc) factor VIII is activated by thrombind) the primary haemostatic plug is formed by platelet aggregation due to thrombine) protein S is a co-factor for protein C
17) Stasis of blood flow results in thrombosis because:
a) disruption of fresh blood flow results in less dilution of activated clotting factorsb) disruption of fresh blood flow results in reduced inflow of inhibitors of clotting factorc) it results in decreased local release of prostacyclin (PG12) and tPAd) all of the above
18) In acute hypovolaemic shock, angiotensin:
a) stimulates the central nervous system’s ischaemic responseb) is responsible for the reverse stress-relaxation response of the circulatory systemc) is not a significant factor in acute compensationd) inhibits the release of vasopressine) contributes towards compensation after baroreceptor responses have been evoked
19) With regard to the in-vitro clotting of blood samples, all of the following are true EXCEPT:
a) blood usually clots when placed in a glass tube within 4-8 minutesb) clotting can be prevented by adding EDTA which chelates calciumc) recalcified plasma usually clots in 2-4 minutesd) the APPT is performed by adding thromboplastin to recalcified plasmae) the normal APPT is 26-33 seconds
20) Vitamin K is required for the activation of:
a) pre-kallikreinb) Hageman factorc) von Willebrands factord) protein Ce) plasminogen
21) Thrombus formation is inhibited by:
a) von Willebrands factorb) IL-1c) alpha 2 – macroglobulind) TNFe) endothelial cell injury
22) Most pulmonary emboli:
a) cause centrally located pulmonary haemorrhageb) cause pulmonary infarctionc) cause acute right heart failured) are clinically silente) lead to pulmonary hypertension
23) In normal haemostasis:
a) factor V inhibits thrombosisb) alpha 2 macroglobulin is antithromboticc) PGI2 favours platelet aggregationd) platelet aggregation is inhibited by von Willebrands factore) tissue plasminogen activator is responsible for prothrombotic events
24) Normal endothelial cells decrease platelet aggregation by secreting:
a) Interleukin-1b) von Willebrands factorc) prostacyclind) factor Ve) thromboplastin
25) Thrombosis is potentiated by all of the following EXCEPT:
a) von Willebrands factor deficiencyb) protein S deficiencyc) antithrombin III deficiencyd) thrombotic thrombocytopaeniae) acute leukaemia
26) Acute compensatory mechanisms in shock include all the following EXCEPT:
a) baroreceptor reflexesb) reverse stress – relaxation of vascular smooth musclec) the effects of increased aldosterone secretiond) activation of the renin-angiotensin systeme) the central nervous system ischaemic response
27) Prothrombotic characteristics of endothelium include:
a) plasminogen activatorb) prostacyclinc) von Willebrands factord) thrombomoduline) heparin like molecules
Section 2
Haemostasis, Thrombosis and Haemorrhage - Answers
1) E2) B3) C4) E5) A6) E7) E8) C9) B10) B11) C12) B13) D14) C15) D16) D17) E18) E19) D20) D21) C22) D23) B24) C25) A26) C27) C
Section 3Haemorrhage and Shock
1) The classic stages of shock include all of the following EXCEPT:
a) compensated stage which begins with mild hypotension, tachycardia, pallor and cold extremities including septic shock
b) decompensating stage which include decline in blood pressure and rapid pulsec) irreversible shock where all therapeutic efforts are to no availd) full recovery is possible, however there is a much higher mortality with patients with
cardiogenic shocke) all of the above are stages of shock
2) Which statement regarding shock is INCORRECT?
a) cardiogenic shock has a higher mortality than neurogenic shockb) “progressive” / “demonstrated” shock is usually irreversiblec) nephrotic syndrome is associated with loss of fluid from all fluid compartmentsd) oliguria usually precedes diuresise) angiotensin and vasopressin levels increase within one hour
3) Shock:
a) is caused by a loss of 25% of the blood volume in a healthy individualb) is caused primarily by cardiac failure and has a 40% mortality with modern treatmentc) is caused by sudden haemorrhage and will stimulate a maximal response from the renin-
angiotensin system within 10 minutesd) is caused by endotoxins and is mediated largely by the release of ILY and TNF from
macrophagese) will cause the “central nervous system ischaemic response” when the systolic blood
pressure is less than 80mmHg
4) The most potent vasopastic substance is:
a) histamineb) leukotriene C4c) platelet activating factord) TNF-α e) serotonin
5) Mediators of septic shock include all of the following EXCEPT:
a) IL-6b) C5ac) PAFd) catecholamines
e) TNF antibodies
Section 3
Haemorrhage and Shock – Answers
1) A2) B3) D4) B5) E
Section 4
Haemodynamic disorders, thrombosis and shock
1) Hypercoagulability:
a) is most commonly caused by the factor V Leiden mutation, present in 1-2% of the white population
b) may be caused by an inherited excess of protein C or protein Sc) can result from a congenitally reduced level of homocysteined) is the most frequent cause of thrombotic diseasee) may be caused by heparin-induced thrombocytopaenia
2) Regarding thrombi, which one of the following statements is NOT true?
a) arterial thrombi usually begin at the site of endothelial damage or turbulence, whereas venous thrombi start in areas of stasis
b) arterial thrombi tend to propagate in a retrograde direction to the point of attachment whereas venous thrombi tend to extend in the direction of blood flow
c) 30% of DVTs in the larger leg veins are asymptomatic and clinically undetectabled) venous thrombosis commonly affects the veins of the lower extremities, with only 10%
occurring in other sitese) activation of the fibrinolytic pathway can lead to total lysis and complete resolution of
recent thrombi
3) Regarding pulmonary emboli:
a) most are clinically detectable by a tachypnoea, dyspnoea and tachycardiab) sudden death and/or cardiovascular collapse occur when over 40% of the pulmonary
circulation is obstructed by embolic) embolic obstruction of medium sized pulmonary vessels results in pulmonary infarction
and loss of respiratory capacityd) fewer than 5% of pulmonary emboli originate outside the deep veins of the legse) multiple pulmonary emboli are unlikely to have a clinical effect if they occur over a
prolonged period of time
Section 4
Haemodynamic disorders, thrombosis and shock – Answers
1) E2) C3) D
Section 5
Haematopoietic System
1) Hereditary spherocytosis:
a) is asymptomatic in 50% of casesb) frequently presents at birth with marked jaundicec) causes cholelithiasis in up to 50% of affected adultsd) causes massive splenic enlargemente) is cured by splenectomy
2) Glucose G phosphate dehydrogenase deficiency:
a) is X-linkedb) is believed to protect against malaria (plasmodium fal????)c) can cause intravascular and extravascular haemolysisd) rarely display the morphologic changes of chronic haemolytic anaemiae) all above are true
3) Sickle cell disease:
a) sufferers are heterozygousb) frequently presents in the neonatal periodc) usually causes splenomegaly in adultsd) involves abnormal alpha-globine) causes “crew haircut” appearance on skull x-rays
4) Sickling may be precipitated by:
a) HbAb) dehydrationc) increased pHd) HbFe) co-existent alpha-thalanaemia
5) The commonest cause of death in children with sickle cell anaemia is:
a) severe anaemiab) infection by unencapsulated bacteriac) vaso-occlusive complicationsd) osteomyelitise) heart failure
6) Αlpha-thalanaemia:
a) is more common than beta-thalanaemiab) is more severe than beta-thalanaemiac) can cause intrauterine death (hydrops foetalis)d) is rarely asymptomatic e) usually requires regular transfusions
7) Beta-thalanaemia:
a) involves excess beta-globin productionb) causes spherocytes in peripheral blood ?????c) results in ineffective erythropoiesisd) is manifest at birth in severe casese) is a cause of primary haemochromatosis
8) Paroxysmal nocturnal haemoglobinuria:
a) is a congenital hereditary conditionb) affects white cell, platelet and red cell functionc) is rarely fatald) is not associated with aplastic anaemiae) causes paroxysmal and nocturnal intravascular haemolysis in more than 75% cases
9) Immune haemolytic anaemia of warm antibody type includes:
a) systemic lupus erythematosusb) syphilisc) mycoplasma pneumoniaed) measlese) mumps
10) Causes of folic acid deficiency include:
a) ileac resectionb) anticonvulsantc) pernicious anaemiad) vegetarianisme) ????? infection with fish tapeworm
Section 5
Haematopoietic System – Answers
1) C2) E3) E4) B5) B6) C7) C8) B9) A10) B
Section 6
Leucopoenia, Leukocytosis, spleen, blood group
1) The normal spleen:
a) stores >50% body plateletsb) stores 30-40ml of red blood cellsc) is frequently the site of primary diseased) is an important primary organ of the immune systeme) has a periarteriolar sheath of β lymphocytes
2) Splenomegaly in adults can be caused by all EXCEPT:
a) amyloidosisb) Epstein-Barr virusc) multiple myelomad) rheumatoid arthritise) sickle cell anaemia
3) Patients with polycythaemia veins:
a) frequently have splenomegaly in the early stagesb) usually have a haematocrit of ≥ 60%c) are all hypertensived) have normal levels of erythropoietin (serum)e) usually present with thrombotic episodes
4) The most common site of multiple myeloma lesions is:
a) vertebral columnb) skullc) pelvisd) femure) clavicle
5) Severe infections tend to occur when the neutrophil count drops below:
a) 100 cells/mm3 bloodb) 500 cells/mm3 bloodc) 1000 cells/mm3 bloodd) 1500 cells/mm3 bloode) 3000 cells/mm3 blood
6) Basophilic leukocytosis is seen in:
a) severe burnsb) periphagusc) inflammatory bowel diseased) myeloproliferative diseasee) non Hodgkin lymphomas
7) The life-span of a neutrophil in the circulation is:
a) 6-7 hoursb) 12-24 hoursc) 24-45 hoursd) 4-5 dayse) none of the above
8) Blood transfusion reaction is an example of a:
a) type I hypersensitivity reactionb) type II hypersensitivity reactionc) type III hypersensitivity reactiond) type IV hypersensitivity reactione) (rather embarrassing monumental cock-up)
9) Regarding rhesus blood groups:
a) rhesus antibodies are innateb) there are three types of rhesus factorsc) rhesus ‘D’ is the mast prevalent and antigenic rhesastad) most Caucasians are “rhesus negative”e) maximal antibody response occurs 2-4 weeks after initial exposure
10) Type O blood:
a) can be safely transfused into anyoneb) contains anti A and anti B antigens at birthc) red cells have O, A and B antigens on their surfaced) is the commonest blood type in Caucasianse) show maximal anti-A and anti-B titres in 20-30 year old
Section 6
Leucopoenia, leukocytosis, spleen, blood groups – Answers
1) B2) E3) B4) A5) B6) D7) A8) B9) C10)D11)D
Section 7
1) In acute infection which cytokine is responsible for the leukocytosis?
a) IL-1b) IL-2c) IL-4d) IL-5e) IFN-X
2) Which of the following conditions would a barophitic leukocytosis be most likely in?
a) bacterial infectionb) asthmac) myeloproliferative conditionsd) parasitic infectione) myelodysplastic conditions
3) Neutropenia associated with ineffective granulopoiesis include:
a) hypersplenismb) aplastic anaemiac) alkylating agents (CXT)d) SLEe) vitamin B12 deficiency
4) Lead poisoning leads to a:
a) megaloblastic anaemiab) haemolytic anaemiac) microcytic anaemiad) hypodromic anaemiae) aplastic anaemia
5) Acute cold agglutinin haemolytic anaemia is seen in:
a) SLEb) lymphomac) leukaemiad) mycoplasma infectione) paroxysmal cold haemoglobinuria
Section 7
Answers
1) A2) C3) E4) B5) D
Section 8
Haematology
1) Monocytosis is seen in:
a) burnsb) non-Hodgkin lymphomac) chronic myelogenous leukaemiad) inflammatory bowel diseasese) hay fever
2) Mycoplasmal infections can cause:
a) megaloblastic anaemiab) aplastic anaemiac) warm antibody haemolytic anaemiad) cold agglutinin immune haemolytic anaemiae) cold haemolysis haemolytic anaemia
3) Sickle cell disease:
a) is seen in heterozygotes for Hbsb) if severe, is present at birthc) splenomegaly is a late signd) painful bone crises are extremely common in childrene) is a type of intravascular haemolytic anaemia
4) Folic acid deficiency is seen in:
a) vegetarianismb) gastrectomyc) disseminated cancerd) fish tapeworm infectione) ileitis
5) Regarding pernicious anaemia:
a) it is an important cause of folic acid deficiencyb) intrinsic factor is secreted by chief cells in stomachc) it is usually diagnosed in adolescenced) intrinsic factor complexes with vitamin B12 in the stomach
e) it is associated with myelin degeneration of dorsal and lateral tract
Section 8
Haematology – Answers
1) D2) D3) D4) C5) E
Section 9
Endocrine
1) Which is the most common pituitary adenoma?
a) non-functioning adenomab) growth hormone adenomac) prolactin cell adenomad) ACTH cell adenomae) mixed growth hormone – prolactin adenoma
2) Regarding Hashimoto thyroiditis:
a) women are five times more frequently affected than menb) some cases are HLA-B8 associatedc) caused primarily by a B cell defectd) antibodies are directed against the iodine transportere) presents as a symmetric, diffuse, painful enlargement of the thyroid, usually with
hypothyroidism
3) Which feature is most frequently seen in Cushing syndrome?
a) osteoporosisb) moon facesc) weakness and fatigabilityd) hypertensione) central obesity
4) Which is NOT an example of secondary hyperaldosteronism?
a) congestive heart failureb) Conn syndromec) renal artery stenosisd) hypoalbuminaemiae) pregnancy
5) Which is the most common cause of Addison’s disease?
a) autoimmune adrenalitisb) tuberculosisc) metastatic cancerd) acute haemorrhagic necrosis
e) drug-induced – of ACTH
Section 9
Endocrine – Answers
1) C2) D3) E4) B5) A
Section 10
Haematopoietic System
1) Regarding pernicious anaemia:
a) it is more common among Mediterranean and Chinese peopleb) atrophic gastritis with failure of IF production is characteristicc) tapeworm infestation may sometimes be a caused) becomes more rare in advancing age groupse) failure of terminal ileal receptor sites for IF is a common cause
2) Regarding B12 deficiency:
a) dietary deficiency may deplete normal reserves after several weeksb) failure of B12 protein R splitting in elderly people may be a causec) pepsin is not normally involved in the process of B12 absorptiond) without IF, there can be no B12 absorption at alle) anaemia and spinal degeneration can be reversed with folate
Section 10
Haematopoietic System - Answers
1) B2) B
Section 11
1) Which primary tumour is not responsible for ectopic ACTH production?
a) islet cell tumours of the pancreasb) carcinoid tumoursc) ductal cancer in the site of the breastd) small cell cancer of the lung
2) With respect to adrenocortical insufficiency, which is TRUE?
a) Addison’s disease is commonly caused by infiltrative disease such as ????serb) hyperpigmentation is not seen in this conditionc) Na+ and K+ losses result in hypokalaemia and hyponatraemiad) resolution is normal with adequate cortisol replacemente) acute Waterhouse–Fridericksen syndrome responds well to appropriate steroid
replacement
3) In the anterior pituitary, which is TRUE?
a) somatotrophs make up the major cell componentb) thyrotrophs produce TSH and lipotropinc) stimulation is via axons from the ??? supraoptic and paroventricular nuclei in the
hypothalamusd) tumours of the pituitary are normally recognised by the mass effects with the cranium
4) Hypothyroidism, which is TRUE?
a) is uncommonly caused by autoimmune destruction of the thyroidb) may result in elevated TSH levels detectable by blood testc) can cause gynaecomastia and amenorrhoead) commonest cause in region with adequate iodine is drug induced
5) Parathyroid hormone:
a) is secreted by the action PTH release proteinb) commonest cause of secretion is primary hyperplasiac) over activity causes bone, kidney, gastrointestinal and central nervous system
symptomsd) parathyroid levels are low in primary hyperparathyroidism
6) The commonest cause of hypothyroidism in iodine sufficient areas of the world is:
a) Hashimoto thyroiditisb) developmental lack of thyroid parenchymac) developmental deficiency of enzymes of thyroid hormone syndromed) due to antithyroid medicationse) radiation damage to thyroid gland
7) Regarding pituitary, which is TRUE?
a) 50% of the pituitary gland is adenohypophysisb) posterior pituitary derives from Ratrike’s pouchc) corticotrophs and thyrotrophs are acidophilic cellsd) the commonest type of pituitary adenoma is prolactin secreting adenomase) non-functional adenoma are usually microadenomas
8) Regarding prolactin, which is TRUE?
a) level decreases in hypothyroidism and renal failureb) level decreases by use of reserpinec) level decreases by neurolepticsd) non prolactin secreting adenomas can increase the pituitary prolactin secretion by stalk
effecte) prolactin levels decrease by use of oestrogens
9) Which is false regarding null cell adenomas?
a) null cell adenomas contribute to 20% of pituitary adenomasb) they do not produce hormonesc) they can cause pituitary apoplexyd) they contain large numbers of secreting granulese) they cause hypothyroidism by destruction of normal pituitary cells
Section 11
Answers
1) C2) D3) A4) B5) C6) A7) D8) D9) D
Section 12
Haemostasis, Thrombosis and Embolism
1) Concerning thromboembolism:
a) the majority of pulmonary emboli arise from deep calf vein and popliteal thrombosisb) about 40% of pulmonary emboli are clinically silentc) pulmonary hypertension is a common sequelae in pulmonary embolismd) cardiomyopathy is the commonest cause of systemic embolie) the risk of renal infarction from thromboembolus is approximately equivalent to the risk
of cerebral infarction
2) Concerning thrombi:
a) arterial thrombi propagate in a retrograde direction (against flow)b) increased levels of protein C and S are risk factors for thrombic) “lines of Zahn” are more prominent in venous than arterial thrombid) deep venous thrombosis occurs in the following order of frequency: deep calf,
popliteal, femoral, iliace) femoral artery thrombi are rarely occlusive
3) Which of the following deficiency syndromes will predispose a patient to a bleeding disorder?
a) protein C deficiencyb) protein S deficiencyc) factor XII (Hageman factor) deficiencyd) vitamin C deficiencye) PGI2 deficiency
4) Of all hospitalised deaths, what percentage are wholly or largely due to pulmonary embolus?
a) 5%b) 10%c) 20%d) 50%e) 75%
5) Which statement regarding tests in bleeding diseases is INCORRECT?
a) clotting time is prolonged in thrombocytopaeniab) partial thromboplastin time detects changes in the intrinsic pathwayc) Hess’ test is a measure of capillary fragilityd) prothrombin time detects changes in the extrinsic pathwaye) bleeding time is affected by the degree of hyperanaemia of the skin
6) Regarding thrombus formation, which of the following is INCORRECT?
a) platelets aggregate when there is a decrease in intraplatelet levels of cyclic AMPb) primary haemostatic plug is formed due to the release of ADPc) platelet adhesion requires von Willebrands factord) protein C deficiency increases the tendency to thrombus formatione) fibrin predominates in a pale thrombus
7) Which clotting factor is NOT synthesised by the liver?
a) IXb) VIIc) IVd) IIe) V
8) Regarding disseminated intravascular coagulation, which of the following statements is INCORRECT?
a) it involves the development of numerous microthrombib) it is often a primary disorderc) it involves active fibrinolysisd) it is associated with increased FDPse) it involves consumption of platelets and clotting factors
9) Which of the following is NOT found in alpha-granules of platelets?
a) fibrinogenb) platelet derived growth factorc) ADPd) platelet factor IVe) fibronectin
10) Regarding the clotting cascade, which of the following is INCORRECT?
a) formation of “prothrombin activator” is the rate limiting factorb) intrinsic pathway is more rapid than extrinsic pathwayc) enough thrombin can be generated by clotting of 1ml of blood to coagulate all the
fibrinogen in 3000mls of bloodd) proteins C and S are reaction acceleratorse) C’1 inactivator neutralises some activated clotting factors
11) Which statement regarding embolism is INCORRECT?
a) amniotic fluid embolism has about 85% mortalityb) gas embolism may lead to ischaemic necrosis of bonec) about 99% of emboli are thrombotic in origind) most systemic thrombotic arise from valvular lesionse) free fatty acids induce toxic injury to micro-vessels in fat embolism syndrome
12) Regarding anti-thrombin III, which statement is INCORRECT?
a) it combines with the inactivates most serine proteasesb) anti-thrombin III deficiency usually presents in late adolescence or early adult lifec) its action is enhanced by both exogenous and endogenous heparind) it blocks the action of IIa on Ie) it is a beta globulin
13) Which statement regarding platelets is INCORRECT?
a) PGI2 promotes platelet aggregationb) they have a life span of about 10 daysc) degranulation leads to activation of platelet factor IIId) they cannot synthesise cyclo-oxygenasee) they carry class 1 MHC antigens
14) Which clotting factor is NOT vitamin K dependent?
a) IIb) IXc) Xd) Ve) VII
15) Which of the following is NOT found in dense bodies of platelets?
a) factor IVb) histaminec) adrenalined) beta-thromboglobuline) serotonin
16) The control mechanisms of coagulation (anticoagulant) include all of the following EXCEPT:
a) the depletion of clotting factorsb) the clearance of activated factorsc) stasis and turbulence of blood flowd) the inhibition of activated proteasese) fibrinolysis
17) Anti-thrombotic factors include all of the following EXCEPT:
a) thrombomodulinb) protein Cc) anti-thrombin IIId) von Willebrands factore) tissue plasminogen activator
18) Which of the following is the most important natural constraint to coagulation?
a) protein Cb) anti-thrombin IIIc) protein Sd) endogenous heparine) endogenous tPA
19) Regarding the fibrinolytic system, which of the following is INCORRECT?
a) urokinase-like plasminogen activators (uPA) activate plasminogen in the fluid phaseb) alpha-one-antitrypsin inhibits action of plasminc) interleukin-1 inhibits synthesis of tPA-inhibitorsd) tissue-type plasminogen activators (tPA) are mainly synthesised in endothelial cellse) small amounts of plasmin are formed in the blood all the time
20) Which of the following is NOT a platelet agonist (ie, does NOT induce platelet aggregation)?
a) ADPb) nitric oxidec) thrombind) adrenalinee) thromboxane A2
21) Thrombosis is potentiated by all of the following EXCEPT:
a) von Willebrands factor deficiencyb) protein S deficiencyc) antithrombin III deficiencyd) thrombotic thrombocytopaeniae) acute leukaemia
22) Prothrombotic characteristics of endothelium include?
a) plasminogen activatorb) prostacyclinc) von Willebrands factord) thrombomoduline) heparin-like molecules
23) Hageman factor activates the:
a) complement systemb) kinin systemc) fibrinolytic systemd) coagulation systeme) all of the above
Section 12
Haemostasis, Thrombosis and Embolism - Answers
1) E2) A3) E4) B5) A6) E7) C8) B9) C10) B11) D12) E13) A14) D15) D16) C17) D18) B19) C20) B21) A22) C23) E
Viva AnswerBLOOD GROUPS
There are more than 30 groups of commonly occurring antigens on RBC,The two groups of greatest clinical significance are:
1 ABO2 Rhesus
ABO
Possible blood groups; O, A, B, ABInherited antigens on RBC surface:
Gp O no surface antigens (O,O)Gp A A surface antigens (AA or AO)Gp B B surface antigens (BB or BO)Gp AB A and B surface antigens (AB)
Do not possess antibodies at birth – but exposed AB antigens in food, or bacteria etc and develop antibodies spontaneously in early life
Gp O → A and B antibodiesGp A → B antibodiesGp B → A antibodiesGp AB → no antibodies
Anti A antibody levels are two times higher than anti B levels.Antibody levels decline with time (peak at 10 years)
ABO Transfusion Reaction
Antigen transfused RBC
Antibody serum recipient Type II hypersensitivity rx????
Red cell clumping. Small red cell plugs in circulation Complement activation → lysis of RBC Opsonisation → phagocytosis (neutrophils and macrophages)
RhesusSix Rh factors; C, D, E, c, d, eInherit one of each type of factor; C or c and D or d and E or eD is widely prevalent and most antigenic
AnaemiaDefinition:
Reduction in circulating red cell mass below normal limits for individual’s age and gender
ClassificationAcute versus chronicMechanism: Blood loss (acute/chronic)
hereditaryintrinsic
Increased RBC destruction acquiredextrinsic
stem cell abnormalityImpaired RBC production
maturation abnormality
By RBC appearance RBC size : micro / normo / macrocyticRBC pigmentation : hypo/normochrome
Classification by mechanism
1 Blood loss; acute : trauma, haemorrhagechronic: GIT bleeding, menorrhazia
2 Increased RBC destruction; Haemolytic anaemiasIntrinsic: hereditary: RBC membrane disorder, eg Hereditary spherolytosis
RBC enzyme deficiency, eg GGPDDisorder RBC synthesis, eg deficient globulin thalassaemia
eg abnormal globin sickle cell
acquired: RBC membrane defect, eg paroxysmal nocturnal haemoglobinuria
3 Impaired RBC productionStem cell disturbance : aplastic anaemia, anaemia of CRF, Problem with RBC maturation : defective DNA synthesis: ↓B12, folate
defective Hb synthesis : ↓iron
TOPIC QUESTION ESSENTIAL KNOWLEDGE NOTESHaematology Discuss Rhesus blood
group and its importanceRhesus antigens are antigens occurring on RBCs that are known to induce clinically significant immunologic disease via type II hypersensitivity /X. The other common group of antigens being the ABO group.6 factors - C, D, E, c, d, e (inherent of each). - antigen D (Rh+) is widely prevalent and most antigenic - exposure of Rh- mother to Rh+ blood from foetus →
development of antibodies over 2-4 weeks
Subsequent exposure (eg snd pregnancy) causes serious type II hypersensitivity /X
→ erythroblastosis foetalis (jaundice, anaemia and hepatosplenomegaly)
Haematology Classify the haemolytic anaemias
Anaemia is decreased oxygen transport capacity of blood secondary to deficiency in RBCs.
Males - Hb < 135gm/ml, Females – Hb < 120gm/ml
Haemolytic anaemia is increased rate of destruction of RBCs, characterised by
1 shortened life span of RBCs2 accumulation of products of HB
catabolism 3 marked increased erythropoiesis
Classification (various methods)1 Extravascular haemolysis (spleen)2 Intravascular haemolysis
Extravascular haemolysis- injured or less deformable RBCs- hereditary sphenocytosis- sickle cell anaemia- G6PD deficiency Intravascular haemolysis- normal RBCs damaged by mechanical injury (eg
mechanical heart valves, thrombi in microcirculation)- complement fixation (transfusion of mismatched blood)- exogenous toxic factors (falcipam and clostridin)- immune haemolytic anaemias
1 warm antibody type (lymphoma, leukaemia, dwas, SLE)
2 cold agglutinin type (mycoplasma, EBV, lymphoma)3 cold haemolysis (paroxysmal cold haemoglobinuria)