Haematology Flashcards
The main component involved in stabilising the primary haemostatic plug.
Fibrin
A serine protease which assists in the break down of blood clots by binding to the clot and localising agents which break it down.
Tissue plasminogen-activator (t-PA)
A potent inhibitor of plasmin in the blood.
a2 macroglobulin
Alpha 2 macroglobulin acts as an antiprotease and is able to inactivate an enormous variety of proteinases. It functions as an inhibitor of fibrinolysis by inhibiting plasmin and kallikrein. It functions as an inhibitor of coagulation by inhibiting thrombin.
A single chain glycoprotein, synthesised by the liver and endothelium, which has strongly anticoagulant action and is important in the mode of action of heparin.
Antithrombin III
It is an important enzyme present in blood that degrades many blood plasma proteins, including fibrin clots.
plasmin
This product of the cyclic endoperoxides induces platelet aggregation
Thromboxane A2
A 6 foot 7 inch rower presents to his GP complaining of easy skin bruising. On further examination he is found to have pectus excavatum, lax joints and a high-arched palate.
Ehlers-Danlos syndrome

A 62 year old overweight woman presents to the Emergency Department following a Road Traffic Accident. A full set of investigations is carried out – which shows an increased Activated Partial Thromboplastin Time (APTT) and Prothrombin Time (PT)/INR
vitamin K deficiency
A 25 year old man presents to the Emergency Department a day after attending his dentist for a routine check-up. After treatment at the dentists the previous day, his gums had not stopped bleeding. On investigation, his APTT and bleeding time are prolonged but a normal PT.
von Willebrand deficiency
↓ platelet function and ↓ factor VIII (vWF carries factor VIII in circulation)
o Mostly autosomal dominant affecting 1/10,000 o Presentation: often bleeding indicative of platelet disorders (i.e. mucocutaneous bleeding) but can also include bleeding indicative of coagulation disorders
o Diagnosis:↑APTT, ↑bleedingtime
↓FactorVIII,↓vWFAg. NormalINR&plts o Management:Desmopressin,VWFandFactorVIIIconcentrates
A 16 year old girl presents to the Haematology Outpatients clinic describing a fluctuating history of easy bruising, epistaxis and menorrhagia.
On investigation there is:
- a thrombocytopaenia with increased megakaryocytes on BM examination.
- ATP
- Glycoprotein IIb/IIIa on platelets
- Anti Platelet Antibody Steroids
- IVIG
- Anti-D Antibody,

Factor VIII deficency
Hemophila A X-linked recessive affecting 1/10,000 males
o Presentation: often early in life or prolonged bleeding after surgery/trauma
o Diagnosis: ↑APTT, normal PT and ↓ factor VIII assay.
oManagement:AvoidNSAIDsandI
Minjections,desmopressin(vWFrelease which is VIII carrier), factor VIII concentrates as replacement which is life long

Factor IX
Chrismas Diseases X-linked recessive affecting 1/10,000 males o Presentation: often early in life or prolonged bleeding after surgery/trauma o Diagnosis: ↑APTT, normal PT and ↓ factor IX assay. o Severity:relatedtofactorleveleg.sev<1%,mod1-5%,mild5-25% o Management:AvoidNSAIDsandIMinjections,desmopressin(vWFrelease which is VIII carrier), factor VIII concentrates as replacement which is life long
It inhibits platelet activation and is also an effective vasodilator.
Prostacylin
Which protein, important in haemostasis, is vitamin K dependent but is not a serine protease? Which option is required as a cofactor for protein C activity?
What does it do?
Protein S
Inhibits factor Va and XIII
Which option synthesises TF, vWF, prostacyclin, plasminogen activator, antithrombin III and thrombomodulin?
Vascular endothelium
Which enzyme, important for platelet aggregation, is irreversibly inhibited by aspirin?
Cyclooxygenase
Which key clotting factor activates both factors V and VIII, and also activates protein C?
Thrombin

can reversibly inhibit Factor Xa
While Xa is inhibited, the Xa- “ XXXX’’ complex can subsequently also inhibit the FVIIa-TF complex.
Tissue factor pathway inhibitor (or TFPI) is a single-chain polypeptide which can reversibly inhibit Factor Xa (Xa). While Xa is inhibited, the Xa-TFPI complex can subsequently also inhibit the FVIIa-tissue factor complex.

It connects intrisinc and extrinsinc pathway
Factor X
22 year old Saharawi refugee presents with anaemia, weight loss, loose stools (malnutrition vitamins ADEK and blood tests reveal an increased PT/INR and slightly increased APTT, with normal thrombin time and platelet count.
vitamin K deficiency
- increased PT/INR = vitamin K
A 5 year old boy has the following blood results: normal PT, increased APTT, normal platelet count, decreased VIII:C and decreased vWF.
vWF The most common hereditary bleeding disorder, affect 1% of the population. vWF is a carrier protein for factor VIII and stabilises it. Mutation is in chromosome 12
A 32 week pregnant lady who has gestational diabetes and is epileptic has a caesarean section while on holiday in rural China. Her newborn baby is suffering from bleeding from the umbilical stump, as well as nose and gums. What is wrong with the baby?
vitamin K deficiency- babies in the UK are given vitamin K post-birth
IgA mediated vasculitis In children < 10 years Preceding URTI Palpable purpuric rash (lower libs extensors + buttocks) Colicky abdo pain Glomerulonephritis Arthritis Orchitis
HSP
Skull bossing, maxillary hypertrophy, hairs on end skull X-ray, Hepatosplenomegaly

β Thalassaemia:
o β- thalassaemia major (homozygous) → 3-6mths severe anaemia, FTT, hepatosplenomegaly (extramedullary erythropoiesis), bony deformity, severe anaemia + heart failure
Diagnosis: Hb electrophoresis (Guthrie at birth) Treatment: blood transfusions and desferrioxamine to stop iron overload, plus folic acid
Point mutations – ↓ β-chain synthesis (spectrum of disease), excess α-chains ↑HbA2 and HbF
o β- thalassaemia minor (heterozygous) → Asymptomatic carrier, mild anaemia




















