Flashcards in More CP Deck (92):
What is haematocrit?
Vol % rbcs in blood
Is haematocrit higher or lower in children?
Zeta + epsilon = what sort of Hb?
Zeta + gamma =?
Alpha + epsilon
Hb gower 1 is ?
Zeta + epsilon
Hb Portland is ?
Zeta + gamma
Hb gower 2 is ?
Alpha + epsilon
When are Hbs gower1, portland and gower 2 present?
4-14 weeks gestation
When does HbF become present?
more than 14 weeks gestation
Difference in WBCs in children?
Which Ig crosses the placenta?
Which Igs in breast milk?
When do babies start producing their own antibodies?
When can babies have their own satisfactory immune responses?
When do platelets reach adult numbers?
18 weeks gestation
What are 2 features of gestational platelets?
Larger initially but reduce to adult size by birth
Hyperresponsive to vWF
Which clotting factors are normal at birth? What are the rest of them like?
Fibrinogen, FV, VIII, XIII
Rest are reduced
When do haemostatic parameters reach adult values?
What is vitamin k dependent other than factors 10, 7, 9, 2?
Proteins S and C
What does routine neonatal vit k injections prevent?
Haemorrhagic disease of the newborn
What are 5 features of neonatal haemostasis?
Pro-coagulant proteins reduced (e.g. all the other factors)
Reduced conc. coagulation inhibitors
unique forms fibrinogen, plasminogen
Raised D dimers and vWF
Platelet aggregation differs
What is acute leukaemia?
Accumulation of early myeloid or lymphoid precursors in BM, blood and other tissues
What are the two main subgroups of acute leukaemia
Acute myeloid leukaemia and acute lymphoblastic leukaemia
How does acute leukaemia present?
Easy bruising or haemorrhage
Possibly organ infiltration by the leukaemia cells
FAB classification of leukaemia is ?
WHO classification of leukaemia is ?
Risk adapted- takes into account prognosis
6 poor prognostic factors in ALL?
Cytogenetic abnormalities (some)
Poor response to Rx
T cell -ALL and null-ALL
2 tests for diagnosis?
Fluorescence activated cell sorting
Treatment for acute leukaemia that is shared with ALL and AML
Induction therapy to obtain remission
Possible BM transplant
Additional Rx in ALL
Prophylaxis of meningeal leukaemia with intrathecal methotrexate and cranial irradiation
Siblings have a ?% change of being a bone marrow donor match?
What is neutropenic sepsis?
All pts with acute leukaemia receiving intensive chemotherapy will become neutropenic for 10-21 days.
Overwhelming gram negative or positive infection= sepsis.
What is neutropenic fever?
Pyrexia in the presence of neutrophil count of less than 1.0/10^9/L
What is the management of neutropenic sepsis?
Immediate broad spectrum IV Abx (often Tazocin and gentamicin) given empirically- within 30 mins of temperature
Prevention of neutropenic sepsis?
Granulocyte colony stimulating factors
Strict hand hygeine
Which element of virchow's triad contributes to arterial thrombosis?
Which elements of virchow's triad contributes to venous thrombosis?
Venous stasis and hypercoagulable state
What are arterial thrombi made of?
What are venous thrombi made of?
Definition of a hospital acquired VTE?
Within 90 days discharge
Having considered the risks of bleeding and VTE, if there is a risk of bleeding how can you still help prevent a VTE?
Mechanical methods eg stockings
When must you reassess risks of bleeding and VTE?
Within 24hrs admission and whenever the clinical situation changes
True of false antiplatelets are adequate prophylaxis against VTE alone?
False, also mobilisation and hydration
4 pharmacological methods of prevention
1. low molecular weight heparin (antithrombin and mostly anti-Xa)
3. Rivaroxaban/apixaban (direct factor Xa inhibitor)
4. Dabigatran (direct thrombin inhibitor)
What is the exclusion test for a VTE?
Use Wells score and D-dimer in an algorithm
What are D-dimers?
Breakdown product of fibrin clots
PE- CT, VQ- compare inhaled and injected isotopes. Mismatch is diagnostic of a PE
Advantages of Rivaroxaban/apixaban/dabigatran over heparin?
Dose uniform rather than done by weight so monitoring not needed
Rapid onset of action
Management for a first episode of DVT or PE
Treat for 3-6 months if there is a temporary risk factor such as pregnancy
What is warfarin target INR?
Management for recurrent episodes of cardiothoracic emboli?
Long term anticoagulation
Management of a proximal DVT or PE that has occured in the absence of a reversible risk factor?
Consider long term anticoagulation
Management if they have recurrent VTEs even on therapeutic anticoagulants?
Increase target INR to 3.5 for warfarin
What is a thrombophilia (2 definitions)
1. familial/acquired predisposition to thrombosis
2. patients who develop VTE spontaneously, extra bad or recurrently at an early age
What is the action of protein C and what is it activated by?
Thrombin-thrombomodulin complex activates it (thrombomodulin is on the vessel wall), protein C-protein S complex breaks down factor Va and VIIIa resulting in coagulation.
In factor V leiden, factor V is resistant to what?
When is factor V leiden asymptomatic?
Are screening tests valuable in factor V leiden?
Debatable as often wouldn't change management. Doesn't increase risk of recurrent thrombosis.
What is prothrombin 20210A?
Increased prothrombin levels, 3 fold increase in VTE
What is the dx criteria for antiphospholipid syndrome?
Presence of antiphospholipid antibodies on at least 2 occasions 8-12 weeks apart in assoc with VT, AT or recurrent foetal loss (more than 2)
What might antiphospholipid syndrome be secondary to?
SLE, conn tissue disorders etc.
When should you screen for thrombophilia?
In younger patients, positive Fhx and if management will change.
Folate and B12 deficiency cause what type of anaemia?
Main cause and other 4 causes of folate deficiency?
Dietary main cause
What is iron transported in?
What is iron stored in?
2 causes of microcytic anaemia
3 causes of iron deficiency
Increased demand (pregnancy,growth)
Redued intake (diet, malabsorption)
Rx for iron deficiency
Oral iron (although constipation and abdo pain)
IM iron (although painful and skin colour change)
IV iron probably best
How do B12 and folate deficiencies cause anaemia?
B12 required for cell folate generation, folate required for nitrogenous base synthesis which make up DNA
What foods is B12 from?
Describe the absorption of B12
Gastric parietal cells absorb
Bound to intrinsic factor
Receptors in terminal ileum
How long are B12 stores sufficient for?
3 causes of B12 deficiency
Gastric problems (pernicious anaemia, gastrectomy)
Small intestine problems (resection, crohns, stagnant loops, jejunal diverticulitis, tropical sprue, fish tapeworm)
Severe B12/folate deficiency can result in...?
What neurological problem can B12 deficiency result in?
Sub acute degeneration of the spinal cord
Rx B12+/folate deficiency?
Give B12 and folate until B12 deficiency is excluded as folic acid in isolation can make B12 def worse.
7 cases haemolytic anaemia
Enzyme defects (G6PD)
Antibodies to RBC
What is the name of haemolytic anaemia in its own right?
autoimmune haemolytic anaemia (AIHA)
steroids and immune suppression
What sort of aneamia is anaemia of chronic disease?
What is the MCV in anaemia of chronic disease?
3 reasons anaemia of chronic disease happens?
Abnormal Fe metabolism
Poor EPO response
Poor BM response
11 causes of thrombocytopenia
drugs alcohol toxins
infection (sepsis, EBV, HIV)
Immune thrombocytopenic purpura
Thrombotic thrombocytopenic purpura
Immune thrombocytopenic purpura cause in children
Post viral- self limiting
Rx immune throbocytopenic purpura
IV Igs (blocks spleen)
What is the role of the spleen in terms of platelets?
How does Immune thrombocytopenic purpura present?
Bruising, petechiae, bleeding
Cause of thrombotic thrombocytopenic purpura
Immune (ADAMTS-13, vWF)
Presentation of thrombotic thrombocytopenic purpura
Fever, neurological, haemolysis