Haematology Flashcards
(124 cards)
1
Q
What is anaemia?
A
Defined as low haemoglobin concentration, may be due either to a low red cell mass or increased plasma volume
Low Hb = <135g/L for men, <115g/L for women
2
Q
What are the symptoms of anaemia?
A
Fatigue, dyspnoea, faintness, palpitations, headache, tinnitus, anorexia
3
Q
What are the signs of anaemia?
A
Pallor, hyper dynamic circulation e.g. tachycardia
4
Q
What are the pathological consequences of anaemia?
A
Myocardial fatty change, fatty change in liver, aggravate angina/ claudication, skin and nail atrophic changes
5
Q
What is the normal mean cell volume?
A
MCV should be 76-96 femtolitres
6
Q
What are the 4 main types of anaemia?
A
Microcytic - low MCV
Normocytic - normal MCV
Microcytic - high MCV
Haemolytic - can be normocytic/macrocytic
7
Q
What are the causes of microcytic anaemia?
A
Iron-deficiency anaemia (most common) Thalassaemia Sideroblastic anaemia (rare)
8
Q
What are some examples of microcytic anaemias?
A
Iron deficiency, anaemia of chronic disease, sideroblastic anaemia, thalassaemia
9
Q
What are the causes of normocytic anaemia?
A
Acute blood loss, anaemia of chronic disease, renal failure
10
Q
What are some examples of normocytic anaemia?
A
Aplastic anaemia, haemolytic - sickle cell disease, infections - malaria, haemorrhage
11
Q
What are the causes of macrocytic anaemia?
A
B12/folate deficiency
Alcohol excess - liver disease
Hypothyroidism
Marrow infiltration
12
Q
What are some examples of macrocytic anaemia?
A
Megaloblastic
B12/folate deficiency
Pernicious anaemia
13
Q
How is anaemia diagnosed?
A
FBC + film, reticulocyte count, B12/folate/ferritin
Iron deficiency - ferritin, iron studies
Chronic disease - lab + clinical investigation, renal failure
B12 deficiency - intrinsic factor antibodies, Schilling test, B12 replacement
14
Q
What is iron-deficiency anaemia and how is it caused?
A
A reduction in Hb concentration due to inadequate iron supply. Microcytic
Causes: blood loss, menorrhagia, malabsorption, poor diet
15
Q
What are the signs and tests for iron-deficiency anaemia?
A
Tiredness, often asymptomatic
Blood film: microcytic, hypochromic anaemia
Decreased MCV, MCH and MCHC
Low ferritin
16
Q
How is iron-deficiency anaemia treated?
A
Treat the cause, give oral iron e.g. ferrous sulfate
17
Q
What is anaemia of chronic disease and what are its causes?
A
Reduced Hb related to chronic inflammatory disorders, chronic infections and malignancy. Microcytic/ normocytic
Causes: chronic infection/inflammation, vasculitis, autoimmune disorders, renal failure, malignancy
18
Q
What are the tests for anaemia of chronic disease and how is it treated?
A
Ferritin normal, check blood film - B12, folate, TSH and tests for haemolysis
Treat underlying disease, give erythropoietin to raise Hb levels
19
Q
What is sideroblastic anaemia?
A
A form of anaemia in which the bone marrow produces ringed sideroblasts rather than healthy blood cells.
20
Q
What is the pathology behind sideroblastic anaemia?
A
Ineffective erythropoiesis, leading to increased iron absorption and iron loading in marrow - body has enough iron but cannot incorporate it into Hb
21
Q
How is sideroblastic anaemia tested for and treated?
A
Increased ferritin, hypochromic blood film, sideroblasts in the marrow
Remove the cause, repeat transfusion for severe anaemia
22
Q
What are the causes of folate deficiency?
A
Macrocytic anaemia - poor diet, malabsorption, alcohol, drugs (methotrexate)
23
Q
How is folate deficiency tested for and treated?
A
Blood film - large oval macrocytes, serum and red cell folate assay
Assess for underlying cause
Treated with folic acid
24
Q
What is pernicious anaemia?
A
Macrocytic - an autoimmune condition in which atrophic gastritis leads to a lack of IF secretion from the parietal cells of the stomach. Dietary B12 therefore remained unbound and consequently cannot be absorbed by the terminal ileum
25
How does pernicious anaemia present?
Fatigue, dyspnoea, jaundice, irritability, depression
| Neurological (B12 causes) - paraesthesia, peripheral neuropathy
26
How is pernicious anaemia tested for and treated?
FBC: decreased Hb, increased MCV
Megaloblasts in the bone marrow, IF antibody test
Treat cause - oral B12
27
What is haemolytic anaemia?
Anaemia due to haemolysis, the abnormal breakdown of red blood cells
28
What is aplastic anaemia and how is it caused?
Anaemia due to bone marrow failure (bone marrow stops making cells)
Causes: autoimmune, drugs, viruses, irradiation, inherited
29
How does aplastic anaemia present?
Symptoms and signs of anaemia, bruising with minimal trauma, blood blisters in mouth
30
How is aplastic anaemia tested for and treated?
Marrow examination needed, pancytopenia, hypo cellular aplastic bone marrow with increased fatty space
Support blood count, bone marrow transplant, immunosuppression
31
What is polycythaemia vera?
A condition marked by an abnormal increase in the number of circulating red blood cells.
32
How does polycythaemia vera present?
May be asymptomatic, headaches, dizziness, visual disturbance, itching after a hot bath, burning sensation in finger and toes, facial plethora, splenomegaly
33
How is polycythaemia vera diagnosed?
FBC: increased RCC, Hb, PCV, WBC and platelets
JAK 2 testing
Marrow shows hyper cellularity with erythroid hyperplasia
34
How is polycythaemia vera managed?
Aim to keep haematocrit <0.45 to reduce risk of thrombosis. Low dose aspirin
35
What are haemoglobinopathies?
Genetic diseases of haemoglobin. Categorised by thalassaemia syndromes and structural haemoglobin variants
36
Explain the genetic pathology of sickle cell disease
Sickle cell anaemia is an inherited autosomal recessive disorder in which the production of abnormal haemoglobin results in vaso-occlusive crises.
HbS is caused by a point mutation in the beta globin gene on chromosome 11. Has polymerises into rod-like aggregates which cause the red cell to adopt a sickle shape
37
How does sickle cell anaemia present?
Asymptomatic, asthenia, jaundice and ulcers around the ankles. Bone deformities and infections
38
What are the complications of sickle cell anaemia?
Acute - painful crisis, sickle chest syndrome, stroke
| Chronic - renal impairment, pulmonary hypertension, joint damage
39
How is sickle cell anaemia diagnosed?
Neonatal screening, blood test: increased reticulocytes and bilirubin
Hb electrophoresis - single major HbS band
Film - sickle cells
Sickle solubility test: +ve
40
How is sickle cell anaemia managed?
Disease modifying treatment - transfusion, stem cell transplant, prophylaxis in cases of hyposplenism and immunocompromised
Hydroxycarbamide
41
What is thalassaemia?
A group of inherited red cell disorders caused by the underproduction of alpha/beta globin chains
42
What is beta thalassaemia major and how does it present?
Significant abnormalities in both beta-globin genes, presenting with severe anaemia and failure to thrive.
Failure to feed, lacking energy, crying, pale
43
How is beta thalassaemia major diagnosed?
FBC: MCV and MCH very low
Film: large and small very pale red cells, nucleated RBCs
Hb electrophoresis
44
How is beta thalassaemia major managed?
Regular transfusions, iron chelation, endocrine supplementation, ferritin monitoring
45
What is iron overload?
Thalassaemia major requires lifelong blood transfusions to grow and develop. This consequently increases the body iron load - there is no means for the body to eliminate the excessive iron.
Excess iron is deposited mainly in the liver and spleen - leading to liver fibrosis and cirrhosis.
Deposited in endocrine glands and heart - diabetes, heart failure and premature death
46
What is alpha thalassaemia?
There are two separate alpha-globin genes on each chromosome 16 - four genes termed aa/aa. When one/some of these are deleted, it is termed alpha thalassaemia
47
What are membranopathies?
Autosomal dominant conditions which result in an abnormally shaped red cell. Deficiency of red cell membrane proteins caused by a variety of genetic lesions
48
What is hereditary spherocytosis?
Shortage of red blood cells, autosomal dominant, less deformable spherical RBCs, so trapped in spleen - extravascular haemolysis
49
What is hereditary elliptocytosis?
Abnormally large number of the erythrocytes are elliptical, autosomal dominant, mostly asymptomatic
50
What is glucose-6-phosphate dehydrogenase (G6PD) deficiency?
X-linked recessive, lack of enzyme that maintains protective protein against oxidant injury. May get oxidative crises due to decreased glutathione production but most are asymptomatic.
51
How is G6PD deficiency tested for and treated?
Enzyme assay, film: bite and blister cells
| Transfuse if severe
52
What is pyruvate kinase deficiency?
Autosomal recessive, decreased ATP production causes decreased RBC survival, may have haemolysis and splenomegaly in later life
53
Where are platelets produced?
Bone marrow
54
How does platelet dysfunction present?
Mucosal bleeding, easy bruising, petechiae, Purpura, traumatic haematomas
55
Name some conditions that result in low platelets due to decreased marrow production?
Aplastic anaemia, megaloblastic anaemia, marrow replacement
56
Name some conditions that result in low platelets due to excess destruction?
Immune thrombocytopenia, thrombotic thrombocytopenia
57
How are platelet dysfunctions managed?
Immunosuppression, treat underlying cause, clopidogrel and aspirin to inhibit a function of the platelets, splenectomy is last resort
58
Define thrombosis
The formation of a blood clot in a blood vessel.
59
Where can abnormal arterial thrombi occur?
Coronary circulation - MI
Cerebral circulation - strokes
Peripheral circulation - gangrene/ PVD
60
What are the risk factors for abnormal blood clotting?
Smoking, hypertension, diabetes, hyperlipidaemia, obesity/ sedentary lifestyle, stress/ type A personality
61
What drugs can be used to manage abnormal blood clotting?
Heparin, LMW heparin, aspirin, warfarin, DOACs
62
How does heparin manage abnormal blood clotting?
Binds to antithrombin and increases its activity (indirect thrombin inhibitor)
63
How does aspirin manage abnormal blood clotting?
Inhibits cycle-oxygenase irreversibly, and inhibits thromboxane formation and hence platelet aggregation
64
How does warfarin manage abnormal blood clotting?
Prevents synthesis of active factors II, VII, IX and X, antagonist of vitamin K - prolongs prothrombin time
65
How do DOACs manage abnormal blood clotting?
Directly acting on factor II and X, used for extending thromboprophylaxis
66
What is deep vein thrombosis?
A blood clot that develops within a deep vein in the body, usually in the leg
67
What is thromboembolism?
The obstruction of a blood vessel by a blood clot that has become dislodged from another site in the circulation
68
What are the causes for DVTs/ Thromboembolisms?
Circumstantial - surgery, immobilisation, long haul flights
Genetic - Factor V Leidein, antithrombin deficiency
Acquired - anti-phospholipid syndrome, lupus anticoagulant
69
How can DVTs/ thromboembolisms be prevented?
Mechanical - hydration and early mobilisation, compression stockings, foot pumps
Chemical - LMW heparin
70
What is thromboprophylaxis?
The prevention of clots forming in the veins
71
How do DVTs/thromboembolisms present?
Symptoms and signs are non-specific, clinical diagnosis unreliable.
Pain, swelling, tenderness, warmth, decolorisation
72
How are DVTs/thromboembolisms diagnosed?
D-dimer: normal excludes diagnosis
US compression test proximal veins
Venogram for calf
73
How are DVTs/thromboembolisms managed?
Oral warfarin, LMWH, DOAC, compression stockings, treat underlying cause
74
What is a pulmonary embolism?
A blockage in one of the pulmonary arteries in your lungs, often caused by blood clots that travel to the lungs from the legs (DVTs).
75
How do pulmonary embolisms present?
Breathlessness, pleuritic chest pain, cyanosis, tachycardia, no signs of alternative diagnosis (differential diagnosis of chest pain and SOB)
76
How are pulmonary embolisms diagnosed?
ECG: sinus tachycardia
Blood gases: type 1 RF, decreased O2 and CO2
D-dimer: normal excludes diagnosis
77
How are pulmonary embolisms managed?
IV alteplase to thrombolyse
| LMWH, DOAC, warfarin
78
Give some examples of vascular defects
Congenital - connective tissue disease
| Acquired - Senile Purpura, infection, steroids
79
Give some examples of coagulation disorders
Congenital - haemophilia, von Willebrand's disease
| Acquired - anticoagulants, liver disease, vitamin K deficiency
80
What is von Willebrand Disease?
An inherited bleeding tendency caused by a quantitative or qualitative deficiency of vWF
81
Describe the pathology of von Willebrand disease
vWF acts as an adhesion molecule which allows platelets to bind to sub endothelial tissues and it also acts as a carrier for factor VIII.
Lack of vWF leads to a bleeding tendency due to a combination of failure of platelet adhesion and factor VIII deficiency
82
What is haemophilia A?
An inherited disorder of haemostasis characterised by bleeding tendency due to a deficiency of factor VIII
83
What is haemophilia B?
An inherited disorder of haemostasis characterised by bleeding tendency due to a deficiency of factor IX
84
How is haemophilia A treated?
Avoid NSAIDs and IM injections, desmopressin raises factor VIII levels
85
How is haemophilia B treated?
Recombinant factor IX
86
What is acute lymphoblastic leukaemia (ALL)?
A malignancy of lymphoid cells (lymphoblasts), affecting B/T lymphocyte cell lineages, arresting maturation and promoting uncontrolled proliferation of immature blast cells, with marrow failure and tissue infiltration
87
How does acute lymphoblastic leukaemia present?
Marrow failure - fatigue, SOB
Infection - tonsilitis, fevers
Bleeding - thrombocytopenia
Hepato/splenomegaly
88
How is acute lymphoblastic leukaemia diagnosed?
Characteristic blast cells on blood film and bone marrow
89
How is acute lymphoblastic leukaemia treated?
Blood/platelet transfusions, IV fluids, Hickman line for IV access
Chemotherapy
90
What is acute myeloid leukaemia?
Neoplastic proliferation of blast cells derived from marrow myeloid elements (myeloblasts)
91
How does acute myeloid leukaemia present?
Marrow failure - infection, bleeding
| Infiltration - hepatosplenomegaly, gum hypertrophy
92
How is acute myeloid leukaemia diagnosed?
Bone marrow biopsy - AML differentiated from ALL by Auer rods
WCC is often increased
93
How is acute myeloid leukaemia treated?
Chemotherapy, supportive measures - blood transfusion, IV fluids
Bone marrow transplant
94
What is chronic myeloid leukaemia?
An uncontrolled clonal proliferation of myeloid (basophils, neutrophils, eosinophils) cells
95
What is the Philadelphia chromosome?
A hybrid chromosome comprising reciprocal translocation between the long arms of chromosome 9 and the long arm of chromosome 22 – t(9;22).
96
How does chronic myeloid leukaemia present?
Weight loss, tiredness, fever, sweats, bleeding, splenomegaly, hepatomegaly, anaemia, bruising
97
How is chronic myeloid leukaemia diagnosed?
WBC - increased neutrophils, monocytes, basophils, eosinophils
Film: left shift + basophilia
Philadelphia chromosome
98
How is chronic myeloid leukaemia treated?
Target molecular therapy - Imatinib (Tyrosinase kinase inhibitors)
99
What is chronic lymphocytic leukaemia (CLL)?
A progressive accumulation of a malignant clone of functionally incompetent beta cells.
100
How does chronic lymphocytic leukaemia present?
Anaemia, infection-prone, weight loss, sweats, enlarged, rubbery, non-tender nodes, splenomegaly
101
How is chronic lymphocytic leukaemia diagnosed?
Increased lymphocytes, autoimmune haemolysis, marrow infiltration
102
How is chronic lymphocytic leukaemia treated?
1st line - chemotherapy (rituximab)
| Transfusion, IV human immunoglobulin, stem cell transplantation, radiotherapy,
103
What is a lymphoma?
A malignant growth of white blood cells - predominantly the lymph nodes but also found in the blood, bone marrow, liver and spleen
104
What is characteristic about Hodgkin's lymphoma?
Characteristic Reed-Sternberg cells with mirror-image nuclei
105
How does Hodgkin's lymphoma present?
Enlarged, non-tender, rubbery superficial lymph nodes, systemic symptoms, anaemia, hepatomegaly
106
How is Hodgkin's lymphoma diagnosed?
Tissue diagnosis - lymph node biopsy (Reed-Sternberg cells)
| Imaging - CXR, CT of thorax, abdo and pelvis
107
What are the stages for Hodgkin's lymphoma?
Ann Arbor system
I - confined to a single lymph node region
II - 2 or more nodal areas on same side of diaphragm
III - nodes on both sides of diaphragm
IV - spread beyond lymph nodes on both sides of diaphragm.
A - asymptomatic, B - presence of B symptoms (weight loss, unexplained fever, night sweats)
108
How is Hodgkin's lymphoma managed?
IA-IIA: radiotherapy and short course chemotherapy
IIA-IVB: longer course chemotherapy
ABVD: Adriamycin, Bleomycin, Vinblastine, Dacarbazine
109
What is characteristic about Non-Hodgkin's lymphomas?
These are all lymphomas without Reed-Sternberg cells
110
What are the causes of Non-Hodgkin's lymphoma?
Immunodeficiency - drugs, HIV
| Infection - Helicobacter pylori
111
How does Non-Hodgkin's lymphoma present?
Superficial lymphadenopathy, extra-nodal disease, dyspepsia, weight loss, diarrhoea, fever, night sweats
112
How is Non-Hodgkin's lymphoma diagnosed?
Marrow and node biopsy: classify high/low grade
Staging - CT of chest, abdomen, pelvis
Bloods
113
How are low-grade Non-Hodgkin's lymphomas managed?
Indolent, often incurable and symptomless
Radiotherapy curative in localised diseases
Remission maintained by rituximab
114
How are high-grade Non-Hodgkin's lymphomas managed?
More aggressive, often curable with systemic symptoms
| Chemotherapy - rituximab, prednisolone
115
What is a myeloma?
A malignant tumour of the bone marrow involving myeloma cells
116
What is multiple myeloma and what is it characterised by?
Neoplastic proliferation of bone marrow plasma cells
| Monoclonal protein in urine, CRAB end organ damage, excess plasma cells in bone marrow
117
How do myelomas present?
Tiredness and malaise, bone pain, fractures, recurrent bacteria infections, anaemia, osteolytic lesions, renal failure
118
How are myelomas diagnosed?
Proteins in the blood (monoclonal protein band in serum or urine electrophoresis)
CRAB - calcium, renal, anaemia, bone
Excess of 10% plasma cells in bone marrow on biopsy
119
How are myelomas managed?
```
Analgesia for bone pain
Bisphosphonate to reduce fracture rates
Local radiotherapy
Trasnfusions to correct anaemia
Chemotherapy
```
120
What is malaria?
An infectious disease caused by protozoan parasites from the Plasmodium family – transmitted by the bite of the Anopheles mosquito or by a contaminated needle or transfusion. Most commonly P. falciparum
121
Describe the life cycle of the malaria parasite
Plasmodium sporozoites are passed on via bite of mosquito.
Travel to liver and infect hepatocytes
Proliferate into merozoites -> infect and multiply in red cells/ mature into gametocytes which infect another mosquito
The rupture of erythrocytic schizonts produces clinical manifestations of malaria
122
What are the clinical manifestations of malaria?
Fever, headache, malaise, myalgia, diarrhoea, cough
123
How is malaria diagnosed?
Detailed travel history
Microscopy of thick and thin blood smear with giemsa stain
Rapid diagnostic test detection of parasite antigen
124
How is malaria managed?
Artemisinin combination therapy (ACT) achieve rapid clearance of parasites by combined action at different stages of the parasite cycle.
Chloroquine phosphate
