HAEMATOLOGY Flashcards
what are the investigations for CLL?
● Normal or low Hb
● Raised WCC with very high lymphocytes
● Blood film – smudge cells may be seen in vitro
What is the treatment for CLL?
- Watch and wait
- Chemotherapy
- Monoclonal antibodies, e.g. rituximab
- Targeted therapy, e.g. bruton kinase inhibitors (ibrutinib)
- human IV immunoglobulins
what is the epidemiology of ALL?
Mainly a childhood disease
highest prevalence between 2-4yrs
Associated with Down’s syndrome
Associated with ionising radiation
what are the investigations for ALL?
● FBC and blood film
o WCC = high
o Blast cells on film and in bone marrow
● CXR and CT scan looking for mediastinal and abdominal lymphadenopathy
● Lumbar puncture to look for CNS involvement
Give 3 environmental causes of leukaemia
- Radiation exposure
- Chemicals (benzene compounds)
- Drugs
What is lymphoma?
Malignant proliferation of B and T lymphocytes in the lymph nodes
Although predominantly in the lymph nodes, what other organs can lymphoma effect?
- Blood
- Bone marrow
- Liver
- Spleen
Give 4 risk factors for lymphoma
- Primary immunodeficiency
- Secondary immunodeficiency - HIV, transplant recipients
- Infections - EBV, H. pylori, HTLV-1
- Autoimmune disorders - SLE, RA
Describe the pathophysiology of lymphoma
Impaired immunosurveillance and infected B cells escape regulation and proliferate
What are the 2 sub-types of lymphoma
- Hodgkins lymphoma
2. Non-hodgkins lymphoma
What are signs and symptoms of Hodgkins lymphoma?
- Fever and sweating
- Enlarged rubbery non-tender nodes
- Systemic ‘B’ symptoms, e.g. fever
- Painful nodes on drinking alcohol
- some patients (commonly young women) have disease localised to the mediastinum
What is needed for the diagnosis of Hodgkins lymphoma?
Presence of Reed-Sternberg cells (in lymph node biopsy)
What blood results may you seen in someone with Hodgkins lymphoma?
High ESR FBC - anaemia (normochromic normocytic) Reed Sternberg cells Low Hb High serum lactase dehydrogenase
Describe the staging go Hodgkins lymphoma
Stage 1 = confined to a single lymph node region
Stage 2 = Involvement of two or more nodal areas on the same side of the diaphragm
Stage 3 = Involvement of nodes on both sides of the diaphragm.
Stage 4 = Spread beyond the lymph nodes e.g. liver.
Each stage is either ‘A’ - absence of ‘B’ symptoms or ‘B’ - presence of ‘B’ symptoms
What the treatment for Hodgkins lymphoma?
ABVD chemotherapy regime
marrow transplant
What are the possible complications of treatment for Hodgkins lymphoma?
- Secondary malignancies
- IHD
- Infertility
- Nausea
- Alopecia
What is non-hodgkins lymphoma?
Any lymphoma not involving Reed-Sternberg cells
what are the signs and symptoms of non-hodgkins lymphoma?
Fever and sweating
Enlarged rubbery non-tender nodes
Systemic ‘B’ symptoms, e.g. fever
GI and skin involvement
What is the treatment for non-hodgkins lymphoma?
Steroids
Monoclonal antibodies to CD20 -> Rituximab
CHOP regimen
What is anaemia?
A reduced RBC mass +/- reduced Hb concentration
What is the functions of Hb?
It carries and delivers oxygen to tissues
What organs are responsible for the removal of RBCs?
- Spleen
- Liver
- Bone marrow
- Blood loss
what are the causes of microcytic anaemia?
- Iron deficiency
- Chronic disease - cancer, HF, CKD
- Thalassaemia
what are the causes of normocytic anaemia?
- Acute blood loss
- Chronic disease
- Combined haematinic deficiency (iron and B12 deficiency)
- renal failure
- pregnancy
- hypopituitarism, hypothyroidism, hypoadrenalism
Give 3 causes of macrocytic anaemia
- B12/folate deficiency
- Alcohol excess –> liver disease
- Haemolytic anaemia
- Hypothyroidism
- bone marrow infiltration/failure
- myeloma
Briefly describe the pathophysiology of anaemia
Reduced O2 transport –> tissue hypoxia –> compensatory mechanism = increased tissue perfusion, increased O2 transfer to tissue, increase RBC production
What pathological changes occur due to anaemia?
- Heart/liver fat change
- Ischaemia
- Skin/nail atrophy
- CNS death
- Aggravate angina and claudication
What do reticulocytes show you?
Marker of balance between formation and removal of RBCs
Give 4 symptoms of anaemia
Non-specific
- Fatigue
- Dyspnoea
- Headache
- Faintness
- Palpitations
- Anorexia
Give 3 signs of anaemia
- Conjunctival pallor
- Hyper-dynamic circulation
- Tachycardia
- Systolic flow murmur
What investigations might you do in someone with anaemia?
- FBC and Blood film
- Reticulocyte count
- B12, folate and ferritin levels
- U+E’s, LFT’s, TSH levels
What is the treatment for anaemia?
Treat the underlying cause
Give 3 causes of iron deficiency anaemia
- Blood loss
- Poor absorption
- Decreased intake in diet
- Increased demand - growth/pregnancy
- Hookworm
Describe the pathophysiology of iron deficiency anaemia
Lack of iron –> no haem production –> lack of effective RBCs
What would the results of investigations be for someone with iron deficiency anaemia?
MICROCYTIC HYPOCHROMIC ANAEMIA
Low ferritin, low reticulocyte
How do you treat iron deficiency anaemia?
Improve diet and treat cause Ferrous sulphate (iron supplement)IV iron if severe
Describe the pathophysiology of B12 deficiency/pernicious anaemia
a lack of B12/intrinsic factor –> B12 not absorbed in terminal ileum –> big facile RBCs
what are the causes of B12 deficiency/pernicious anaemia?
- Autoimmune parietal cell destruction (pernicious)
- Poor diet
- Ileectomy
What are the specific signs of B12 deficiency/pernicious anaemia?
Inflamed tongue (glossitis), angular stomatitis, mild jaundice
Neurological - paraesthesia, psychological problems, ataxia
- dementia and visual disturbances
What would the results of the investigations be for someone with B12 deficiency/pernicious anaemia?
MACROCYTIC NORMOCHROMIC ANAEMIA with polysegmented neutrophils
Autoantibodies = intrinsic factor and coeliac antibodies(intrinsic factor antibodies are diagnostic)
How would you treat B12 deficiency/pernicious anaemia ?
Treat cause
B12 replacement - malabsorption = hydroxocobalamin IM
dietary = oral B12
Describe the pathophysiology of folate deficiency
In folate deficiency there is an impairment of DNA synthesis, resulting in delayed nuclear maturation resulting in large RBCs as well as decreased RBC production in the bone marrow
How do you treat folate deficiency?
Folic acid supplement - with B12
Describe the pathophysiology of haemolytic anaemia
RBC destroyed before 120 day lifespan –> compensatory reticulocytes from BM –> RBC destruction
- Extravascular
- Intravascular
Give 3 inherited causes of haemolytic anaemia
- RBC membrane defect
- Abnormal Hb - thalassaemia’s, sickle cell
- Enzyme defects - Glucose-6-phosphate dehydrogenase deficiency
Give 3 acquired causes of haemolytic anaemia
- Autoimmune
- Drug induced
- Secondary to systemic disease
- Malaria
What is the management for haemolytic anaemia
Dietary = folate and iron supplementation
AI cause = immunosuppression
Surgical = splenectomy
Name the 3 broad categories of red cell disorders
- Haemoglobinopathies
- Membranopathies
- Enzymopathies
What is normal adult haemoglobin made of?
2 alpha and 2 beta chains
What is foetal haemoglobin made of?
2 alpha and 2 gamma chains
What is haemoglobin S?
Variant haemoglobin arising because of a point mutation in the beta globin gene
Mutation leads to a single AA change, Glutamate –> Valine
What two categories can haemoglobinopathies be divided in to?
- Disorders of quality - abnormal molecule or variant haemoglobin (sickle cell)
- Disorders of quantity - reduced production (thalassaemia’s)
What is sickle cell disease?
A haemoglobin disorder of quality
HbS polymerises –> sickle shaped RBC
What is the advantage of being a carrier of sickle cell disease?
Offers protection against falciparum malaria
They are symptom free
Describe the inheritance pattern of sickle cell disease
sickle cell anaemia = Autosomal recessive Homozygous SS
sickle cell trait = heterozygous
If both parents are carries of the sickle trait, what is the chance of their first child having sickle cell disease?
25% chance of having sickle cell
50% chance of being a carrier
How long do sickle cells last for?
5-10 days
Give 3 acute complications of sickle cell disease
- Painful crisis
- Sickle cell syndrome - blockage of blood vessels within bone leading to pain
- Strokes in children
- Infections
Give 3 chronic complications of sickle cell disease
- Renal impairment
- Pulmonary hypertension
- Joint damage
- growth and development problems
- cardiomegaly, MI
- hepatomegaly
- retinopathy
- impaired placental blood flow
What investigations are done to confirm a diagnosis of sickle cell disease?
- Blood film - Sickled erythrocytes seen
- Blood count - Hb range of 60-80 g/L
- Positive sickle solubility test
- Haemoglobin electrophoresis - Confirms diagnosis
- Aim for diagnosis at birth
Describe the treatment for sickle cell disease
- Precipitating factors should be avoided - e.g. infection, dehydration, cold
- Folic acid
- Acute attacks:
- IV fluids
- Analgesia
- Oxygen - Possible blood transfusions
- Oral hydroxycarbamide to reduce frequency of crises
- Stem cell transplant
long term management
- hydroxyurea - increases HbF levels so is used as prophylaxis
- pneumococcal vaccine
What is the significance of parvovirus in someone with sickle cell disease?
Parvovirus is common infection in children
Leads to decreased RBC production and an cause a dramatic drop in Hb in patients who already have a reduced RBC lifespan
Describe the inheritance pattern for membranoapthies
Autosomal dominant
Name 2 common membranopathies
- Spherocytosis
2. Elliptocytosis
Briefly describe the physiology of membranopathies
Deficiency in red cell membrane protein caused by genetic lesions
What are enzymopathies?
Enzyme deficiencies lead to shortened RBC lifespan
Name a common enzymopathy
G6PD deficiency
what are the clinical features of G6PD deficiency?
Most are asymptomatic Pallor Fatigue Palpitations Shortness of breath Jaundice Exacerbated by ingesting fava beans
Name 3 things that can precipitate G6PD deficiency
- Broad beans / fava beans
- Infection
- Drugs - Primaquine, sulphonamide, quinolones
What is polycythaemia?
- increased RBC count
- increased haematocrit
- Due to a JAK2 mutation
What hormone is responsible for regulating RBC production?
Erythropoietin (EPO)
What stimulates EPO?
Tissue hypoxia
what are the primary causes of absolute polycythaemia?
Polycythaemia vera - overactive bone marrow causing increase in RBC mass
what are the secondary causes of absolute polycythaemia?
hypoxia
- Smoking - Lung disease - Cyanotic heart disease - High altitude - obstructive sleep apnoea
Excess EPO - renal disease
alcohol
what are the clinical features of polycythaemia?
Headaches and dizziness Itching Fatigue Tinnitus Erythromelalgia – burning sensation in fingers and toes Hypertension Angina Hepatosplenomegaly (distinguishes 1o from 2o)
What is the treatment for polycythaemia?
No cure Treatment aim is to maintain normal blood count Venesection - relieves symptoms Low does aspirin Radioactive phosphorus in those over 70
Where are platelets produced?
In the bone marrow
They are fragments of megakaryocytes
What hormone regulated platelet production?
Thrombopoietin - produced mainly in the liver
What is the lifespan of a platelet?
7-10 days
What organ is responsible for platelet removal?
Spleen
What can cause platelet dysfunction?
Reduced platelet number (thrombocytopenia)Reduced platelet function
What can cause decreased platelet production?
- Congenital causes (e.g. malfunctioning megakaryocytes)
- Infiltration of bone marrow (e.g. leukaemia)
- Alcohol
- Infection (e.g. HIV/TB)
- Reduced TPO
- Aplastic anaemia
What can cause increased platelet destruction?
- Autoimmune (e.g. ITP)
- Hypersplenism
- Drug related (e.g. heparin induced)
- DIC and TTP –> increased consumption
What can cause reduced platelet function?
- Congenital abnormality
- Medications - aspirin
- VWF disease
- Uraemia
Give 3 symptoms of platelet dysfunction
- Mucosal bleeding - epistaxis, gum bleeding, menorrhagia
- Easy bruising
- Petechiae/purpura
- Traumatic haematomas
Give 4 causes of bleeding
- Trauma
- Platelet deficiency - thrombocytopenia
- Platelet dysfunction - aspirin induced
- Vascular disorders
Give 3 things that can cause coagulation disorders
- Vitamin K deficiency
- Liver disease
- Congenital - haemophilia
What is thrombotic thrombocytopenia (TTP)?
- Widespread adhesion and aggregation of platelets leads to microvascular thrombosis and consumption of platelets
- Occurs due to a reduction in ADAMTS-13 – a protease that is normally responsible for the degradation of vWF
what are the clinical features of thrombotic thrombocytopenia (TTP)
- Flu-like symptoms
- fever, fatigue, aches
- Purpura
- Epistaxis (nosebleeds)
- Easy bruising
- Menorrhagia (heavy periods)
- Haemoptysis (coughing up blood)
- Headache
- Abdominal pain
- GI bleeding
- Chest pain (rare)
What is the treatment for thrombotic thrombocytopenia (TTP)?
- Plasma exchange (removed ADAMTS13 autoantibodies)
- Splenectomy
- IV steroids
- IV methylprednisolone
- IV rituximab
- folic acid
- platelet transfusion = contraindicated
What is immune thrombocytopenia (ITP)?
Antibodies formed against platelet –> autoimmune platelet destruction via reticuloendothelial system
Give 3 causes of immune thrombocytopenia (ITP)
Primary = viral infection (children) Secondary (chronic, adults) - Autoimmune conditions - Malignancies - CLL - Infections - HIV/Hep C
what is the clinical presentation of immune thrombocytopenia (ITP)?
Can by asymptomatic
- Purpura
- bruising and purple/red rash
- Epistaxis (nosebleeds)
- Menorrhagia (heavy periods)
- Prolonged bleeding from the gums
- Severe headache
- Vomiting
- Fatigue
What is the management for immune thrombocytopenia (ITP)?
- first line = Corticosteroid (prednisolone) or IV immunoglobulin - IV IgG
- second line = Splenectomy or immunosuppression (rituximab)
Give 4 causes of folate deficiency
- Dietary
- Malabsorption
- Increased requirement - pregnancy
- Folate antagonists - methotrexate
Give 3 signs of haemolytic anaemia
- Pallor
- Jaundice
- Splenomegaly
Give 2 specific symptoms of iron deficiency anaemia
- Koilonychia - spoon nails
- Brittle hair and nails
- Atrophic glossitis
What is neutrophilia?
Too many neutrophils
Give 3 causes of neutrophilia
- Infection
- Inflammation
- Cancer
- CML = primary cause
What is lymphocytosis?
Too many lymphocytes