Haematology Flashcards
What is a myeloma?
A malignant proliferation of the Plasma cells (Type of B lymphocytes)
Define multiple myeloma (MM)?
Malignant proliferation of plasma cells (B lymphocytes) accumulating in the bone marrow that affects multiple areas of the body
What is the second most common haematological cancer?
Multiple Myeloma
What is the pathogenesis of Multiple Myeloma?
Malignant proliferation of plasma cells (B lymphocytes) accumulating in the bone marrow
This leads to overproduction of Ig or Ig fragment (paraprotein)
Causes dysfunction of many organs (especially the kidney), bone marrow failure, destructive bone disease and hypercalcaemia
Characterised by excess secretion of a monoclonal antibody
What is a paraprotein?
Paraprotein → abnormal immunoglobulins produced by clonal plasma cells
They can be intact immunoglobulins (usually IgG, IgA or IgM) or parts of immunoglobulins (usually light chains, very rarely heavy chains)
What are the main paraproteins produced in multiple myeloma?
Typically excess production of 1 specific type of Ig.
55% are IgG
20% are IgA.
What are the preceding steps before established multiple myeloma?
Development of monoclonal gammopathy of undetermined significance (MGUS)
Smouldering myeloma
What is Monoclonal Gammopathy of Undetermined significance (MGUS)?
where there is an excess of a single type of antibody or antibody components without other features of myeloma or cancer.
This is often an incidental finding in an otherwise healthy person and as the name suggests the significance is unclear.
May progress to MM and patients are often routinely monitored.
What is Smouldering Myeloma?
where there is progression of MGUS with higher levels of antibodies or antibody components. It is premalignant and more likely to progress to myeloma than MGUS
What is Waldenstrom’s macroglobulinemia
Waldenstrom’s macroglobulinemia is a type of smouldering myeloma where there is excessive IgM specifically.
What is the rate of progression of MGUS to MM?
1% per year
What is the clinical presentation of multiple myeloma related to?
Infiltration of plasma cells
Secretion of monoclonal antibodies
What are the Risk Factors of Multiple Myeloma?
Older age
Male
Black African ethnicity
Family history
Obesity
Give some symptoms of Myeloma?
Tiredness
Bone/back pain
Infections
What are the signs and symptoms of multiple myeloma?
OLD CRAB:
Old - 70+
C - Hypercalcaemia (& associated symptoms)
R - Renal Failure (hypercalcaemia causes calcium oxalate renal stones and immunoglobulin light chain kappa deposition is nephrotoxic)
A - Anaemia (Bone Marrow Infiltration causing; Neutropenia (infections), Thrombocytopenia (bleeding)
B - Bone Lesions - Pepperpot Skull
How does bone disease arise in multiple myeloma?
Proliferation in bone marrow
Lytic lesions
Fractures
How does impaired renal function arise in multiple myeloma?
Kappa Immunoglobulin light chains (Bence Jones Protein) are nephrotoxic.
& Hypercalcaemia
Why may Renal disease worsen the effects of Anaemia in MM?
Renal disease can lead to EPO deficiency contributing to the anaemia
How does hypercalcaemia arise in multiple myeolma?
Multiple myeloma-induced bone demineralisation and bone resorption
How does recurrent/persistent bacterial infection arise in multiple myeloma?
Immune dysfunction and hypogammaglobulinemia
Suppression of normal plasma cell function
Why does anaemia occur in multiple myeloma?
The cancerous plasma cells invade the bone marrow.
This is described as bone marrow infiltration.
This causes suppression of the development of other blood cell lines leading to:
Anaemia (low red cells),
Neutropenia (low neutrophils)
Thrombocytopenia (low platelets).
What initial diagnostic investigations are ordered in someone with suspected multiple myeloma?
BLIP:
B – Bence–Jones protein (request urine electrophoresis)
L – Serum‑free Light‑chain assay
I – Serum Immunoglobulins
P – Serum Protein electrophoresis
What Investigations are needed to confirm a diagnosis of Multiple Myeloma?
Bone marrow biopsy is necessary to confirm the diagnosis of myeloma and get more information on the disease.
>10% plasma cells
Imaging is required to assess for bone lesions. The order of preference to establish this is:
Whole body MRI
Whole body CT
XR - Skull for pepperpot lesions
What is indicative of MM on bone marrow biopsy?
> 10% plasma cells
What bloods results would be indicative of multiple myeloma?
FBC - marrow failure
ESR - raise
Blood film - Rouleaux formation (RBC Aggregations)
U&Es - raised urea and creatinine
Hypercalcaemia
What are some important differential diagnoses of Multiple Myeloma?
MGUS
What is the treatment for MGUS and asymptomatic myeloma?
Watch and wait.
What is the principle behind treatment of MM?
Multiple myeloma is an incurable condition → treatment aims to increase periods of disease remission
What is the first line treatment for multiple myeloma?
A combination of chemotherapy with:
Bortezomid - proteasome inhibitor
Thalidomide
Dexamethasone - steroid
What else may you consider to treat multiple myeloma?
Stem cell transplant
Bisphosphonates - bone protection
Name the 3 broad categories of red cell disorders.
- Haemoglobinopathies.
- Membranopathies.
- Enzymopathies.
What is a haemoglobinopathy?
Deficiency related to quality or quantity of haemoglobin production
What is a membranopathy?
Deficiency related to red blood cell membrane protein
What is an enzymopathy?
Deficiency related to RBC enzyme synthesis, leads to shortened lifespan due to oxidative stress
What is the normal range for haemoglobin?
120-180g/L
What is normal adult haemoglobin made of?
HbA1:
2 alpha and 2 beta chains.
What is foetal haemoglobin made of?
HbF:
2 alpha and 2 gamma chains.
What is haemoglobin S?
Haemoglobin S is a variant of Hb arising from a point mutation in the beta globin gene.
The mutation leads to a single amino acid change, valine -> glutamine.
What is sickle cell disease?
Auto recessive disorder
A Hb disorder of quality; polymerisation of HbS results in characteristic sickle shaped RBCs
What are the types of Sickle Cell disease based on Inheritance?
- Sickle cell anaemia (HbSS) = inheritance of 2 abnormal sickle genes
- Sickle cell disease (HbSC) = Inheritance of one abnormal sickle gene and second haemoglobin variant of the beta chain that causes sickling. E.g. haemoglobin C
- Sickle cell trait (HbS) = Inheritance of one abnormal sickle gene. Sickle carrier.
- Sickle-thalassaemia (H
What is the lifespan of a Sickle Cell?
5-10 days - described as haemolytic
What is the Pathophysiology of Sickle Cell Anaemia?
- HbS will polymerise at periods of hypoxia and acidosis
- Sickling is precipitated by low oxygen, dehydration, infection, cold exposure and acidosis
- This leads to vaso-occlusion and significantly shortens the life span of an RBC to 10-20 days
- This is due to chronic haemolysis
What can precipitate sickling in Sickle Cell Anaemia?
Trauma
Cold
Stress
Exercise
Why does Sickle Cell Anaemia not present until after 6 months of age?
HbF is not affected by sickle cell anaemia as it is made up of 2 alpha and 2 gamma chains.
Prior to 6 months of age the body still produces HbF
What are reticulocytes?
Immature RBCs that still have RNA material.
Their percentage increases in haemolytic anaemia
What effect does Sickle Cell Anaemia on reticulocyte count?
Raised - 2-3% (normally 0.45-1.8%)
Why is reticulocyte count raised in Sickle Cell Anaemia?
Sickle cell disease is haemolytic - increased degradation of RBC’s
What is the pathogenesis of sickle cell disease?
Point mutation in the Beta globin gene (GAG to GTG) swapping valine for glutamic acid.
This causes irreversible RBC sickling which makes the RBC fragile.
A decreased surface area also means the RBCs are less efficient.
What are the symptoms of Sickle Cell disease?
Jaundice - haemolytic anaemia releasing bilirubin
+ complications of anaemia
Give 4 acute complications of sickle cell disease.
- Vaso-occlusive painful Crisis
- Stroke in children.
- Splenic Sequestration crisis - blocked blood flow to spleen
- Infections - due to hyposlenysm
Give 3 chronic complications of sickle cell disease.
- Renal impairment.
- Pulmonary hypertension.
- Joint damage.
What are some complications of Sickle cell disease?
Anaemia
Increased risk of infection
Stroke
Avascular necrosis in large joints such as the hip
Pulmonary hypertension
Painful and persistent penile erection (priapism)
Chronic kidney disease
Sickle cell crises
Acute chest syndrome
What is Vaso-occlusive Crisis (AKA painful crisis) in sickle cell disease?
Sickle shaped blood cells clogging capillaries causing distal ischaemia.
It is associated with dehydration and raised haematocrit.
Symptoms are typically pain, fever and those of the triggering infection.
What is Splenic Sequestration Crisis?
Red blood cells blocking blood flow within the spleen.
This causes an acutely enlarged and painful spleen.
The pooling of blood in the spleen can lead to a severe anaemia and circulatory collapse (hypovolaemic shock).
What is the significance of parvovirus for someone with sickle cell disease?
Common infection in children (URTI), leading to decreased RBC production
What is the diagnostic test for Sickle cell disease?
Newborn screening - heel prick test
FBC + blood film - increased reticulocytes, sickled RBCs, Howell Jolly bodies
Hb Electrophoresis - diagnostic.
What are the treatments of acute complicated attacks in sickle cell disease?
IV fluids
Analgesia (NSAIDs)
O2
What are the long term treatments for sickle cell disease?
Avoid Dehydration
Hydroxycarbamide - stimulates HbF production
Blood transfusion
Bone marrow transplant
What is the relationship between Sickle cell disease and Malaria?
Having one copy of the sickle cell gene reduces the severity of malaria and is protective.
There is a high proportion of the population in Africa & other malaria associated areas with at least one sickle cell gene.
What is thalassaemia?
An autosomal recessive disorder of haemoglobin quantity.
There is reduced synthesis of one or more globin chains with leading to a reduction in Hb -> anaemia.
Degree of anaemia depends on the type of mutation
Px with defects in Alpha chains have alpha Thalassaemia
Px with defects in Beta chains have beta Thalassaemia
If someone has beta thalassaemia do they have more alpha or beta globin chains?
They have very few beta chains, alpha chains are in excess.
Which is more common, alpha or beta thalassaemia?
Beta thalassaemia is more common
What are some potential signs and symptoms of Thalassaemia?
Microcytic anaemia (low mean corpuscular volume)
Fatigue
Pallor
Jaundice
Gallstones
Splenomegaly
Poor growth and development
Pronounced forehead and malar eminences
Why do you get splenomegaly in thalassaemia?
RBCs in thalassaemia are more fragile and break down easily.
In thalassaemia the spleen collects all the destroyed red blood cells and swells, resulting in splenomegaly.
What are mutations that result in alpha Thalassaemia?
4 genes on chromosome 16
Deletion mutations
What is produced in alpha thalassaemia as a result of the decreased alpha chains?
Excess beta chains form an unstable beta tetramer (HbH)
This is a poor carrier of O2
Where is alpha thalassaemia most prevalent?
- Sub-Saharan Africa
- Middle East
- Mediterranian
- Areas of Asia
What are mutations that result in Beta Thalassaemia?
2 genes on chromosome 11
Can have abnormal functional genes or deletion genes that are non functional resulting in different types of Beta Thalassaemia
What are the 3 types of Beta Thalassaemia?
Thalassaemia Minor
Thalassaemia Intermedia
Thalassaemia Major
What is Thalassaemia Minor?
One abnormal and One functional beta globin gene
Causes mild microcytic anaemia
What is Thalassaemia Intermedia?
Either:
2 defective beta globin genes - retain some function
OR
1 defective and 1 deletion gene
Causes a more significant microcytic anaemia
What is Thalassaemia Major?
Px with Homozygous Beta globin deletion genes.
No functioning beta globin genes
Causes severe anaemia and failure to thrive.
What is the diagnosis of Thalassaemia?
FBC - MCV = shows microcytic anaemia
Haemoglobin Electrophoresis - diagnoses Globin abnormalities
DNA Testing - determine genetic abnormality
Why is Iron overload an issue in Thalassaemia?
Iron overload occurs in thalassaemia as a result of faulty creation of red blood cells, recurrent transfusions and increased absorption of iron in response to the anaemia.
How is Iron overload in Thalassaemia managed?
Monitored Serum Ferritin levels
Limiting transfusions
Iron Chelation
What is the key clinical symptom of Beta Thalassaemia?
Chipmunk Face - due to enlarged forehead and cheekbones due to decreased RBCs and extramedullary haematopoiesis
What is the treatment for Thalassaemia?
Regular Blood transfusions
Iron Chelation - prevent Iron overload
Splenectomy
Folate supplements
Bone marrow stem cell transplant
What is a potential Curative option for thalassaemia?
Bone marrow stem cell transplant
Describe the inheritance pattern for Membranopathies
Autosomal dominant
Name two most common Membranopathies
Spherocytosis (horizontal) - more severe, present neonatal jaundice and haemolysis
Elliptocytosis (vertical)
Describe the pathophysiology of Membranopathies
Deficiency of red cell membrane proteins caused by genetic lesions; haemolytic anaemia.
What are the common clinical features of Membranopathies?
Jaundice
Anaemia
Splenomegaly
What is Hereditary Spherocytosis?
Deficiency in structural membrane protein Spectrin
Makes RBCs more spherical and rigid
Causes Splenomegaly
What are the symptoms of Hereditary Spherocytosis?
General Anaemia
Neonatal Jaundice
Splenomegaly
50% have Gallstones
What is the diagnosis of Hereditary Spherocytosis?
Direct Coombs Negative (positive = Autoimmune Haemolytic Anaemia)
FBC and blood film:
Normocytic Normochromic
Increased Reticulocytes
Spherocytes
What is the treatment for Hereditary Spherocytosis?
Splenectomy
Neonatal Jaundice - Phototheraphy
Name a common Enzymopathy.
G6PD deficiency
What is G6PD Deficiency?
X linked recessive enzymopathy causing 1/2 RBC lifespan and RBC degradation
Why does a deficiency in glucose-6-phosphate dehydrogenase lead to shortened red cell lifespan?
G6PD is required for glutathione synthesis
Glutathione protects Red blood cells against oxidative damage
How does G6PD deficiency present?
Mostly asymptomatic unless precipitated.
May have haemolysis leading to anaemia and jaundice
What is the diagnostic investigations for G6PD Deficiency?
Reduced G6PD levels
Blood film:
Normal in between attacks
Attack - increased reticulocytes and HEINZ bodies and BITE cells
What is the treatment for GP6D Deficiency?
Avoid Precipitants - Oxidative drugs
Blood transfusions when attacks come on.
What precipitants can lead to attacks of GP6D Deficiency?
Naphthalene
Anti-malarials
Aspirin
FAVA beans
Nitrofurantoin
What are lymphomas?
Disorders (cancers) caused by malignant proliferation of lymphocytes inside the lymphatic system.
These cancerous cells accumulate in the lymph nodes causing lymphadenopathy
What are the two main categories of lymphoma?
Hodgkin’s Lymphoma - a specific disease
Non-Hodgkin’s Lymphoma - encompasses all other lymphomas
What are the main Lymph node sites?
Cervical Lymph Nodes
Axillary Lymph Nodes
Inguinal Lymph Nodes
What are some Potential causes of Lymphoma?
Primary Immunodeficiency - Ataxia Telangiectasia
Secondary Immunodeficiency - HIV, Transplant recipients
Infection - EBV, HIV, HTL virus, H-pylori
Autoimmune disorders - SLE
What is the pathophysiology of Lymphoma?
Not well understood
Thought to be multifactorial - Genetic factors + Environment
Impaired Immunosurveillance
Infected B cells escape regulation and proliferate
What is Hodgkin’s Lymphoma?
Cancerous Proliferation of Lymphocytes
Bimodal age distribution - affects teens (13-19) and elderly (75+)
Associated with EBV infection
What are the 2 types of Hodgkin’s Lymphoma?
Classical - Reed Sternberg cells with mirror-Image nuclei
Nodular Lymphocyte Predominates Hodgkin’s Lymphoma (NLPL) - Reed Sternberg cell variant - Popcorn cell
What are the risk factors for Hodgkin’s Lymphoma?
HIV
Epstein-Barr Virus
Autoimmune conditions such as rheumatoid arthritis and sarcoidosis
Family history - affected sibling
How does Hodgkin’s Lymphoma normally Present?
Lymphadenopathy - non-tender, feel rubbery
Pain in lymph nodes when drinking alcohol.
B symptoms - Fever, Weight loss, Night sweats
What are the B Symptoms associated with Lymphoma/other haematological disorders?
Fever
Weight Loss >10% in 6 months
Night Sweats
What other symptoms may be associated with Hodgkin’s Lymphoma?
Fatigue
Pruritus’ (itching)
cough
SOB
Abdominal Pain
Recurrent infections
What are the diagnostic investigations for Hodgkin’s Lymphoma?
Lymph Node Biopsy - Reed Sternberg cell positive with mirror image nuclei
Lactate Dehydrogenase - Often raised by not specific to Hodgkin’s
Decreased Hb, Increased ESR - indicates worse prognosis
CT/MRI - Fir staging and diagnostics
What type of Biopsy is done to Diagnose Lymphoma?
Core Needle Biopsy
Lymph Node Excision
What are Reed Sternberg cells?
Abnormally large B cells with multiple nuclei that are the key finding on lymph node biopsy in Hodgkin’s Lymphoma.
What is the Ann Arbor Staging system?
Used for Staging Hodgkin’s and Non-Hodgkin’s Lymphoma
Stage 1 - Single Lymph node region
Stage 2 - In more than 1 lymph node region but same side of the diaphragm
Stage 3 - Lymph nodes both above and below Diaphragm affected
Stage 4 - Widespread involvement including other non-lymphatic organs (lungs/liver)
A = NO B symptoms
B = HAS B symptoms
What other organs may be affected in Stage 4 Hodgkin’s Lymphoma?
Blood
Bone Marrow
Liver
Spleen
What is used to stage lymphomas using the Ann Arbor staging system?
CT/MRI/PET scans
What is the Treatment for Hodgkin’s Lymphoma?
ABVD Chemotherapy:
Adriamycin
Bleomycin
Viricistine
Dacarbazine
(Potentially Radiotherapy)
What are the different courses of treatment for Hodgkin’s Lymphoma?
Stage IA - IIA (< 3 areas involved):
Short course ABVD
Stage IIA - IVB (> 3 areas involved):
Longer courses of ABVD
What is the Aim of Treatment for Hodgkin’s Lymphoma?
To cure the condition
Usually successful however there is a risk of relapse and SE of treatment.
What are some side effects of Hodgkin’s Lymphoma Treatment?
Chemotherapy:
Alopecia
N+V
Myelosuppression & BM failure = Infection
Radiotherapy - Increased risk of second malignancies
What is Febrile Neutropenia?
A condition marked by Fever and very low neutrophil numbers in the blood.
Massive risk in Px who have had recent/High dose Chemo (or on Carbimazole)
What is the treatment for Febrile Neutropenia?
Immediate Broad Spec Antibiotics
(Amoxicillin + Fluoroquinolone)
What is Non-Hodgkin’s Lymphoma?
All lymphomas without Reed Sternberg cells.
80% are B cell origin and 20% T cell origin.
Give some Key Non-Hodgkin’s Lymphomas
Low Grade - Follicular
High Grade - Diffuse Large B cell Lymphoma
Very high Grade - Burkitt Lymphoma
What are the risk factors of Non-Hodgkin’s Lymphoma?
HIV
Epstein-Barr Virus
H. pylori (MALT lymphoma)
Hepatitis B or C infection
Exposure to pesticides and a specific chemical called trichloroethylene used in several industrial processes
Family history
What are some Specific Symptoms of Burkitt Lymphoma?
Linked to EBV infection.
Causes Massive Jaw Lymphadenopathy in children
What are the symptoms of Non-Hodgkin’s Lymphoma?
Variable symptoms due to the range of subtypes however Px generally present in a similar way to Hodgkin’s Lymphoma:
Painless Rubbery Lymphadenopathy
B Symptoms
Lymph nodes NOT Painful with Alcohol.
What are the Diagnostic tests for Non-Hodgkins Lymphoma?
Lymph Node Biopsy - No RS/Popcorn Cells confirms NHL lymphoma
CT/MRI for Ann Arbor Staging
What is the Treatment for Non-Hodgkin’s Lymphoma?
R-CHOP:
Rituximab - Targets CD20 on B cells
Cyclophosphamide
Hydroxy-Daunorubicin
Vincristine (Oricovin)
Prednisolone
+ radiotherapy
Describe the prognosis of low-grade Non-Hodgkin’s Lymphoma
Slow growing, advanced at presentation, incurable
Median survival; 10 years