Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Y5 Blood > List II - Less Common 'Know of' Conditions > Flashcards

List II - Less Common 'Know of' Conditions Flashcards

1
Q

What is disseminated intravascular coagulation (DIC)?

A
  • Widespread activation of coagulation from release of procoagulants into circulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the clotting pathway?

A
  • Intrinsic/extrinsic pathways
  • Activated Xa
  • Converts prothrombin to thrombin
  • Converts fibrinogen to fibrin (also thrombin activated XIII to XIIIa which crosslinks fibrin)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the fibrinolytic pathway?

A
  • t-PA released from endothelial cells
  • Converts plasminogen to plasmin
  • Cleaves fibrin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the causes of DIC?

A
  • Malignancy - leukaemia (esp. acute promyelocytic leukaemia)
  • Sepsis - meningococcal septicaemia
  • Trauma
  • Obstetric events - retained products (>20 wks), pre-eclampsia, placental abruption, endotoxic shock, aniotic fluid embolism, placental accreta, hydatidiform mole, acute fatty liver of pregnancy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the pathophysiology of DIC?

A
  • Clotting factors and platelets are consumed - increased bleeding risk
  • Fibrin strands fill small vessels - haemolysing passing RBC’s
  • Fibrinolysis activated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the signs of DIC?

A
  • Bruising, bleeding (e.g. venepunture sites), renal failure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the appropriate blood investigations for DIC?

A
  • FBC (low plts)
  • Clotting screen (increased PT, increased APTT, low fibrinogen: correlates with severity)
  • Raised D-dimer (fibrin degradation product)
  • Blood film - schistocytes (haemolysed RBC’s)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the approach to the management of a patient with suspected DIC?

A
  • A to E assessment
  • A - check patency, maintain, sit up
  • B - 15L o2 NRBM
  • C - IV access - bloods (as above) - replace platelets if <50 - cryoprecipitate (to replace fibrinogen) - FFP (to replace clotting factors) - activated protein C (to reduce mortality if severe sepsis/multi organ failure) - treat underlying cause
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the complications of DIC?

A
  • Risk of death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How can DIC be prevented?

A
  • Primary prevention - acute promyelocytic leukaemia

- Give all transretinoic acid (to reduce risk of DIC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is sickle cell anaemia?

A
  • Auto-somal recessive condition that results in synthesis of and abnormal haemoglobin chain termed HbS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Who is affected by SCD?

A
  • More common in people of African decent
  • Offers some protection against malaria
  • 10% of UK Afro-Caribbean’s are carriers of HbS (i.e. heterozygous) - such people are only symptomatic if severely hypoxic
  • Symptoms in homozygous people dont tend to develop until 4-6 months when the abnormal HbSS molecules take over from the fetal haemoglobin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the pathophysiology of SCD?

A
  • Polar amino acid glutamate is substituted by non-polar valine in each of the two beta chains (codon 6) - this decreases the water solubility of dexoy-Hb
  • In the deoxygenated state the HbS molecules polymerise and cause RBC’s to sickle
  • HbAS patients sickle at p02 2.5 - 4 kPa, HbSS patients at p02 5 - 6 kPa
  • Sickle cells are fragile and cause infarction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the investigation for SCD / how is it diagnosed?

A
  • Haemoglobin electrophoresis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are SC crises managed?

A
  • Analgesia e.g. opiates
  • Rehydrate
  • Oxygen
  • Consider antibiotics if evidence of infection
  • Blood transfusion
  • Exchange transfusion e.g. if neurological complications
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the longer term management of SCD?

A
  • Hydroxyurea
  • Increases the HbF levels and is used in the prophylactic management of sickle cell anaemia to prevent painful episodes
  • Sickle cell patients should receive the pneumococcal polysaccharide vaccine every 5 years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is haemophilia?

A
  • Disorder of coagulation - meaning bleed more easily
  • X-linked recessive
  • Up to 30% of patients have no family history
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the cause of haemophilia A?

A
  • Deficiency in factor VIII
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the cause of haemophilia B?

A
  • Deficiency in factor IX (Christmas disease)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the presenting clinical features of haemophilia?

A
  • Haemarthroses, haematomas

* Prolonged bleeding after surgery or trauma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What blood tests can be done for haemophilias?

A
  • Prolonged APTT

* Bleeding time, thrombin time, prothrombin time normal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which problem can occur with treatment for haemophilia A?

A
  • Up to 10-15% of patient will develop antibodies to factor VIII treatment
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are thalassaemias?

A
  • Group of genetic disorders characterised by a reduced production rate of either alpha or beta chains
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is beta-thalassaemia trait?

A
  • Auto-somal recessive condition characterised by mild hypochromic, microcytic anaemia
  • Usually asymptomatic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the clinical features of thalassaemia trait?

A
  • Mild hypochromic, microcytic anaemia - microcytosis is characteristically disproportionate to the anaemia
  • HbA2 raised (>3.5%)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is beta-thalassaemia major?

A
  • Absence of beta chains

* Chromosome 11

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are the clinical features of thalassaemia major?

A
  • Presents in first year of life with failure to thrive and hepatosplenomegaly
  • Microcytic anaemia
  • HbA2 and HbF raised
  • HbA absent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the treatment of thalassaemia major?

A
  • Repeated transfusion - iron overload

* s/c infusion of desferrioxamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is alpha-thalassaemia?

A
  • Due to deficiency of alpha chains in haemoglobin

* 2 separate alpha-globulin genes are located on each chromosome 16

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What determines the clinical severity of alpha-thalassaemia?

A
  • Number of alpha globulin alleles affected
  • 1 or 2 alleles affected then the blood picture would be hypochromic and microcytic, but the Hb would be typically normal
  • 3 alpha globulin alleles affected results in a hypochromic microcytic anaemia with splenomegaly - known as Hb H disease
  • If all 4 alpha globulin alleles are affected (i.e. homozygote) then death in utero (hyrops fetalis, Bart’s hydrops)
31
Q

What is a thrombophilia?

A
  • Blood disorder making blood more likely to clot when you dont want it to
32
Q

What are the inherited thrombophilias?

A

Gain of function of polymorphisms

  • Factor V Leiden (activated protein C resistance) - most common cause of thrombophilia
  • Prothrombin gene mutation - second most common

Deficiences of naturally occurring anticoagulants

  • Antithrombin III deficiency
  • Protein C deficiency
  • Protein S deficiency
33
Q

What are the acquired thrombophilias?

A
  • Anti-phospholipid syndrome

* Combined oral contraceptive pill

34
Q

What is the relative risk of VTE according to thrombophilia?

A
  • Factor V Leiden (heterzygous)
  • P 5%, VTE risk 4%
  • Factor V Leiden (homozygous)
  • P 0.05%, VTE risk 10%
  • Prothrombin gene mutation (heterzygous)
  • P 1.5%, VTE risk 3%
  • Protein C deficiency
  • P 0.3%, VTE risk 10%
  • Protein S deficiency
  • P 0.1%, VTE risk 5-10%
  • Antithrombin III deficiency
  • P 0.02%, VTE risk 10-20%
35
Q

How are patients screened for VTE risk in hospital?

A
  • VTE risk assessment tool to review risk factors including:
  • Medical patients - significant reduction in mobility for 3 days or more (or anticipated to have significant reduced mobility)
  • Surgical/trauma patients -
  • Hip/knee replacement
  • Hip fracture
  • General anaesthetic and a surgical duration of over 90 minutes
  • Surgery of the pelvis or lower limb with a general anaesthetic and a surgical duration of over 60 minutes
  • Acute surgical admission with an inflammatory/intra-abdominal condition
  • Surgery with a significant reduction in mobility
  • General risk factors -
  • Active cancer / chemotherapy
  • Aged over 60
  • Known blood clotting disorder e.g. thrombophilia
  • BMI over 35
  • Dehydration
  • One or more significant medical comorbidities e.g. heart disease, metabolic/endocrine pathologies, respiratory disease, acute infectious disease and inflammatory conditions
  • Critical care admission
  • Use of hormone replacement therapy (HRT)
  • Use of the combine oral contraceptive pill
  • Varicose veins
  • Pregnant or <6 week post partum
36
Q

What are the different types of VTE prophylaxis?

A
  • Mechanical
  • TED / anti-embolic compression stockings - thigh or knee height
  • Intermittent pneumatic compression device
  • Pharmacological
  • LMWH s/c injection
  • Reduced doses should be used in severe renal impairment
  • Unfractionated heparin
  • Alternative to LMWH for patients with CKD
37
Q

What is the advice to patients pre-surgery with regard to VTE?

A
  • Advise women to stop taking their COCP/hormone replacement therapy 4 weeks before surgery
38
Q

What is the advice to patients post-surgery with regard to VTE?

A
  • Try to mobilise patients as soon as possible after surgery

* Ensure the patient is hydrated

39
Q

What is the post surgery VTE advice for patients who have had elective hip surgery?

A
  • LMWH for 10 days followed by aspirin (75mg or 150mg) for a further 28 days
    or
  • LMWH for 28 days combined with anti-embolism stockings until discharge
    or
  • Rivaroxaban
40
Q

What is the post surgery VTE advice for patients who have had elective knee surgery?

A 
* Aspirin (75mg or 150mg) for 14 days
or
* LMWH for 14 days combined with anti-embolism stockings until discharge
or
* Rivaroxaban
41
Q

What is the post surgery VTE advice for patients who have had fragility fractures of the pelvis, hip and proximal femur?

A
  • NICE guidelines:
  • Offer VTE prophylaxis for a month to people with fragility fractures of the pelvis, hip or proximal femur if the risk of VTE outweighs the risk of bleeding
  • Choose either:
  • LMWH, starting 6-12 hrs after surgery or
  • Fondaparinux sodium, starting 6 hours after surgery, providing there is low risk of bleeding
42
Q

What are the causes of severe thrombocytopenia?

A
  • ITP
  • DIC
  • TTP
  • Haematological malignancy
43
Q

What are the causes of moderate thrombocytopenia?

A
  • Heparin induced thrombocytopenia (HIT)
  • Drug induced (quinine, diuretics, sulphonamides, aspirin, thiazides)
  • Alcohol
  • Liver disease
  • Hypersplenism
  • Viral infection (EBV, HIV, hepatitis)
  • Pregnancy
  • SLE/anti-phospholipid syndrome
  • Vitamin B12 deficiency

Pseudothrombocytopenia has been reported in association with the use of EDTA as an anticoagulant

44
Q

What are the features of immune thrombocytopenia in children?

A
  • Antibodies are directed against the glycoprotein IIb/IIIa or Ib-V-IX complex
  • Features in children (compared to adults)
  • Typically more acute than adults
  • Equal sex incidence
  • May follow an infection or vaccination
  • Usually a self limiting course over 1-2 weeks
45
Q

What are the features of immune thrombocytopenia in adults?

A
  • Antibodies are directed against the glycoprotein IIb/IIIa or Ib-V-IX complex
  • Adults have a more chronic condition
  • More common in older females
  • Symptomatic patients may present as follows:
  • Petechiae, purpura
  • Bleeding, epistaxis
  • Catastrophic bleeding e.g. intracranial is not uncommon
46
Q

What is the management of ITP?

A
  • First line treatment is oral prednisolone
  • Pooled normal human immunoglobulin (IVIG) may also be used
  • Splenectomy is now less commonly used
47
Q

What is Evans syndrome?

A
  • ITP in association with auto-immune haemolytic anaemia (AIHA)
48
Q

Which condition is characterised by pancytopenia?

A
  • Aplastic anaemia
49
Q

What are the causes of aplastic anaemia?

A
  • Idiopathic
  • Congenital - Fanconi anaemia, dyskeratosis congenita
  • Drugs - cytotoxics, chloramphenicol, sulphonamides, phenytoin, gold
  • Toxins: benzene
  • Infections: parvovirus, hepatitis
  • Radiation
50
Q

What is the normal range for neurophils?

A
  • 2.0 - 7.5 * 10(9)
51
Q

What is considered a low neutrophil count?

A
  • <1.5 * 10(9)

Further stratified as follows:

  • Mild - 1.0 - 1.5 * 10(9)
  • Moderate - 0.5 - 1.0 * 10(9)
  • Severe - <0.5 * 10(9)
52
Q

What are the causes of neutropenia?

A
  • Viral
  • HIV
  • EBV
  • Hepatitis
  • Drugs
  • Cytotoxics
  • Carbimazole
  • Clozapine
  • Benign ethnic neutropenia
  • Common in black African and Afro-Caribbean
  • No treatment required
  • Haematological malignancy
  • Myelodysplastic malignancies
  • Aplastic anaemia
  • Rheumatological conditions
  • SLE
  • RA
  • Severe sepsis
  • Haemodialysis
53
Q

What are the features of neutropenic sepsis?

A
  • Most common 7-14 days after chemotherapy
  • May be defined as a neutrophil count of <0.5 * 10 (9) in a patient having anti-cancer treatment and the presence of one of the following:
  • High temperature >38c
  • Other signs or symptoms that are suggestive of sepsis
54
Q

What is the prophylaxis for neutropenic sepsis?

A
  • If it is suspected that patients are likely to have a neutrophil count of <0.5 * 10(9) as a consequence of their treatment they should be offered a fluroquinolone
55
Q

How should neutropenic sepsis be managed?

A
  • Antibiotics should be started immediately, do not wait for WBC
  • NICE recommends starting empirical anti-biotic therapy with pipercillin with tazobactam (Tazocin) immediately
  • Many units add Vancomycin if the patient has central venous access but NICE do not support this approach
  • Specialist assessment to see if management can be as outpatient (or admission)
  • If patients are still febrile and unwell after 48 hours an alternative anti-biotic such as meropenem is prescribed +/- vancomycin
  • If patients are not responding after 4-6 days the Christie guidelines suggest ordering investigations for fungal infections e.g. HRCT rather than just starting therapy for anti-fungal blindly
  • Potential role for G-CSF in selected patients
56
Q

What is G-CSF?

A
  • Recombinant human granulocyte-colony stimulating factors used to increase neutrophil counts in patients who are neutropenic secondary to chemotherapy or other factors
  • Examples - filgrastim, perfilgrastim
57
Q

For patients with MM, who are suitable for stem cell transplant, what should their induction therapy consist of?

A
  • Bortezomib and Dexamethasone
58
Q

What does an autologous stem cell transplant involve for people wit MM?

A
  • Removal of the patients own stem cells prior to chemotherapy, which are then replaced after chemotherapy
  • Different from allogenic stem cell transplantation where stem cells are sourced from HLA matching donors
  • Allogenic stem cell transplantation is currently only used as part of clinical trials when treating multiple myeloma
59
Q

What is the most common malignancy affecting children?

A
  • Acute Lymphoblastic Leukaemia (ALL)
  • Accounts for 80% of childhood leukaemia’s
  • Peak incidence is 2-5 years of age and boys are affected slightly more than girls
60
Q

What are the clinical features of ALL?

A

Due to bone marrow failure:

  • Anaemia - lethargy and pallor
  • Neuropenia - frequent or severe infections
  • Thrombocytopenia - easy bruising, petechiae

Others:

  • Bone pain (secondary to bone marrow infiltration)
  • Splenomegaly
  • Hepatomegaly
  • Fever in up to 50% of new cases
  • Testicular swelling
61
Q

What are the types of ALL?

A
  • Common ALL (75%) CD10 present, pre-B phenotype
  • T-cell ALL (20%)
  • B-cell ALL (5%)
62
Q

What are the poor prognostic factors for ALL?

A
  • Age <2 yrs or >10 yrs
  • WBC >20 * 10(9)/l at diagnosis
  • T or B cell surface markers
  • Non-caucasian
  • Male sex
63
Q

What is the most common form of leukaemia in adults?

A
  • Chronic lymphocytic leukaemia (CLL) is caused by monoclonal proliferation of well differentiated lymphocytes which are almost always B-cells (99%)
64
Q

What are the features of CLL?

A
  • Often none - may be picked up as an incidental finding of lymphocytosis
  • Constitutional anorexia, weight loss
  • Bleeding, infections
  • Lymphadenopathy more marked than chronic myeloid leukaemia
65
Q

What are the investigations of CLL?

A
  • FBC - lymphocytosis, anaemia
  • Blood film - smudge cells (also known as smear cells)
  • Immunophenotyping is the key investigation
66
Q

What is the more common type of acute leukaemia in adults?

A
  • Acute myeloid leukaemia (AML)

* May occur as primary disease or following a secondary transformation of a myeloproliferative disorder

67
Q

What are the features of AML related to bone marrow failure?

A
  • Anaemia: pallor, lethargy, weakness
  • Neutropenia: WCC may be high, functioning neutrophil levels are low leading to frequent infections
  • Thrombocytopenia: bleeding
  • Splenomegaly
  • Bone pain
68
Q

What are the poor prognostic factors for AML?

A
  • > 60 years
  • > 20% blasts after first course of chemo
  • Cytogenetics: deletions of chromosome 5 or 7
69
Q

What are the features of acute promyelocytic leukaemia M3?

A
  • Associated with t(15:17)
  • Fusion of PML and RAR alpha genes
  • Presents younger than other types of AML (average = 25 years old)
  • Auer rods (seen with myeloperoxidase stain)
  • DIC or thrombocytopenia often at presentation
  • Good prognosis
70
Q

What is the classification of AML?

A
  • French-American-British (FAB)
  • M0 - undifferentiated
  • M1 - without maturation
  • M2 - with granulocytic maturation
  • M3 - acute promyelocytic
  • M4 - granulocytic and monocytic maturation
  • M5 - monocytic
  • M6 - erythroleukaemia
  • M7 - megakaryoblastic
71
Q

What is chronic myeloid leukaemia associated with?

A
  • Philadelphia chromosome - present in more than 95%
  • Due to a translocation between the long arm of chromosome 9 and 22 - t(9:22) (q34:q11)
  • Results in part of the ABL proto-oncogene from chromosome 9 being fused with the BCR gene to form chromosome 22
  • Resulting BCR-ABL gene codes for a fusion protein which has tyrosine kinase activity in excess of normal
72
Q

What is the presentation of CML?

A
  • Usually 60-70 years
  • Anaemia - lethargy
  • Weight loss and sweating are common
  • Splenomegaly may be marked - abdominal discomfort
  • Increase in granulocyte at different stages of maturation +/- thrombocytosis
  • Decreased leucocytosis alkaline phosphatase
  • May undergo blast transformation (AML in 80%, ALL in 20%)
73
Q

What is the management of CML?

A
  • Imitinab is now first line
  • Hydroxyurea
  • Interferon alpha
  • Allogenic bone marrow transplant
74
Q

What is Imitinab?

A
  • Inhibitor of the tyrosine kinase associated with the BCR-ABL defect
  • Very high response rate in chronic phase CML

Y5 Blood (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions