Haematology Flashcards
What is myeloma?
Malignancy of plasma cells leading to progressive bone marrow failure.
It is associated with production of characteristic paraprotein, bone disease, hypercalcaemia and renal failure.
In order to make a diagnosis of myeloma, there must be evidence of mono-clonality. What is mono-clonality?
Abnormal proliferation of a single clone of plasma cell leading to excess production of a SINGLE TYPE of immunoglobulin and causing organ dysfunction especially to the kidney.
Myeloma results in immunoparesis. What is immunoparesis?
One type of immunoglobulin is produced in excess, and the others are underproduced - IMMUNOPARESIS.
Immunoparesis results in increased susceptibility to infections
What disease often precedes myeloma?
Monoclonal gammopathy of undetermined significance (MGUS).
What is MGUS?
Monoclonal gammopathy of undetermined significance
A common disease with paraprotein present in the serum but no myeloma.
Often asymptomatic.
<10% plasma cells in the bone marrow.
In approximately 2/3 of people with myeloma, what might their urine contain?
Immunoglobulin light chains with kappa or lamda lineage.
What is the clinical presentation of myeloma?
OLD CRAB
- Old age
- Calcium elevated
- Renal failure
- Anaemia
- Bone lytic lesions
- Recurrent bacterial infections
Give 3 symptoms of myeloma.
- Tiredness.
- Bone/back pain.
- Infections.
Give 4 signs of myeloma.
CRAB!
- Calcium is elevated.
- Renal failure.
- Anaemia.
- Bone lesions.
Why is calcium elevated in myeloma?
There is increased bone resorption and decreased formation meaning there is more calcium in the blood.
Why might someone with myeloma have renal failure?
Nephrotic syndrome - due to light chain deposition in kidneys
Results in THIRST due to lack of water retention
Why might someone with myeloma get bone lytic lesions / back pain?
Malignant plasma cells result in;
- Activation of osteoclasts, thus increasing bone turnover and causing bone breakdown and lytic lesions
- Inhibition of osteoblasts, thus decreasing new bone formation
Why might someone with myeloma have anaemia?
The bone marrow is infiltrated with plasma cells.
Consequences of this are anaemia, infections (neutropenia) and bleeding (thrombocytopenia).
What investigations might you do in someone who you suspect has myeloma?
- Blood count - hypercalcaemia, anaemia, thrombocytopenia, neutropenia
- Bone marrow aspirate (trephine biopsy) - looking for plasma cell infiltration
- Serum / urine electrophoresis - monoclonal protein band
- Skeletal survey - “punched out” bone lytic lesions
What would you expect to see on the blood film taken from someone with myeloma?
Rouleaux formation (aggregations of RBCs).
What would the a blood test of a patient with myeloma show?
- Normocytic normochromic anaemia
- Raised ESR
- High calcium
- High alkaline phosphatase
What are you looking for on a bone marrow biopsy taken from someone with myeloma?
Increased plasma cells.
What are you looking for on serum and urine electrophoresis in a patient with myeloma?
Monoclonal protein band.
What are you looking for on an X-ray taken from someone with myeloma?
Bone lesions.
What is the treatment for MGUS and asymptomatic myeloma?
Watch and wait.
Describe the treatment for symptomatic myeloma.
- Pain
- Fractures
- Anaemia
- Further renal damage prevention
- Renal failure
- Infections
- Cancer
- Analgesia for bone pain
- Bisphosphonates to reduce fractures
- RBC transfusion and erythropoietin for anaemia
- 3L/day fluid to prevent renal damage
- Dialysis for acute renal failure
- Broad spectrum antibiotics for infections
- Chemotherapy (CTD = unfit people, VAD = fit people)
What is lymphoma?
A malignant proliferation of lymphocytes which accumulate in lymph nodes and cause lymphadenopathy
Although predominantly in the lymph nodes, lymphoma is systemic. What other organs might it effect?
- Blood.
- Liver.
- Spleen.
- Bone marrow.
Give 4 risk factors for lymphoma.
- Primary immunodeficiency
- Secondary immunodeficiency (e.g. HIV)
- Infection (e.g. EBV, HTLV-1)
- Autoimmune disorders (e.g. SLE)
Describe the pathophysiology of lymphoma.
There is impaired immunosurveillance and infected B cells escape regulation and proliferate. (This is just a theory).
Give 4 symptoms of lymphoma.
- Cervical lymphadenopathy (feel ‘rubbery’)
- Symptoms of compression syndromes.
- General systemic ‘B’ symptoms (e.g. weight loss, night sweats, malaise)
- Hepatosplenomegaly
What investigations might you do in someone who you suspect has lymphoma?
- Bloods
- High ESR / Low Hb
- High serum lactate dehydrogenase - Lymph node biopsy.
- Miror image nuclei Reed-Sternberg cells - CT / MRI chest, abdomen, pelvis - staging
- Immunophenotyping.
- Cytogenetics.
What are the two sub-types of lymphoma?
- Hodgkins lymphoma.
- Non-hodgkins lymphoma.
What are the symptoms of Hodgkins lymphoma?
- Painless lymphadenopathy.
- Presence of ‘B’ symptoms e.g. night sweats, weight loss.
(Some patients, particularly young women, present with cough due to mediastinal lymphadenopathy)
What is needed for diagnosis of Hodgkins lymphoma?
Presence of Reed-sternberg cells.
Describe the staging of 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’ (no systemic symptoms other than pruritis) ‘B’ (presence of B symptoms, e.g. fever, weight loss, etc.)
What is the treatment for stage 1A - 2A Hodgkins lymphoma?
Short course combination chemotherapy (ABVD) followed by radiotherapy.
What is the treatment for stage 2B - 4B Hodgkins lymphoma?
Longer course of combination chemotherapy (ABVD)
What is the ABVD combination chemotherapy treatment?
A - adriamycin
B - bleomycin
V - vinblastine
D - dacarbazine
What are the possible complications of treatment for Hodgkins lymphoma?
- Secondary malignancies (radiotherapy increases risk)
- IHD (radiotherapy)
- Infertility (chemotherapy)
- Nausea (chemotherapy)
- Alopecia (chemotherapy)
Describe low grade non-Hodgkins lymphoma.
- Slow growing
- Advanced at presentation
- Systemic B symptoms
- Pancocytopenia (anaemia, infection, bleeding)
- Often incurable
- Median survival is 10 years
- e.g. follicular lymphoma
What is the treatment for low grade non-hodgkins lymphoma?
If asymptomatic - do nothing.
If symptomatic - Radiotherapy, combination chemotherapy and mAb may be used
Describe high grade non-hodgkins lymphoma.
- Aggressive
- Nodal presentation, patient unwell
- Pancocytopenia
- Systemic B symptoms
- Often curable
- e.g. diffuse large B-cell lymphoma (DLBCL)
Describe the treatment for high grade non-hodgkins lymphoma.
Early - 3 month R-CHOP chemotherapy and radiotherapy.
Advanced - 6 month R-CHOP chemotherapy and radiotherapy
What is R-CHOP chemotherapy regimen?
R - rituximab (monoclonal antibody - mAb)
C - cyclophosphamide
H - hydroxy-daunorubicin
O - vincristine (oncovin - brand name)
P - prednisolone
What is leukaemia?
Malignant proliferation of haemopoietic stem cells in the bone marrow which are non-functional
Name 4 sub-types of leukaemia.
- AML - acute myeloid leukaemia.
- CML - chronic myeloid leukaemia.
- ALL - acute lymphoblastic leukaemia.
- CLL - chronic lymphoblastic leukaemia.
Give 5 symptoms of leukaemia.
- Anaemia.
- Infection.
- Bleeding.
- Hepatomegaly.
- Splenomegaly.
Why are anaemia, infection and bleeding symptoms of leukaemia?
Bone marrow failure
Anaemia - low Hb
Infection - low WCC
Bleeding - low platelets
Why are hepatomegaly and splenomoegaly symptoms of leukaemia?
Liver / spleen infiltration
What investigations might you do on someone who you suspect has leukaemia?
- Blood film (WCC is high, blast cells on film and in bone marrow)
- Bone marrow biopsy.
- Lymph node biopsy.
- Immunophenotyping.
- Cytogenetics.
What is acute myeloid leukaemia?
Neoplastic proliferation of myeloblasts or myeloid stem cells
It causes death in 2 months if untreated
What can increase the risk of developing AML?
- Preceding haematological disorders.
- Prior chemotherapy.
- Exposure to ionising radiation.
How do you diagnose AML?
- Raised WCC (but can be normal / low)
- Few blast cells in peripheral blood so diagnose using bone marrow biopsy
- Differentiate from ALL by microscopy, immunophenotyping and molecular methods
Describe the treatment for AML.
- Supportive care.
- Chemotherapy: curative v palliative.
- Bone marrow transplant.
- Prophylactic antimicrobials
- Allopurinol (prevent tumour lysis syndrome)
- IV fluids through Hickman line
What is CML?
Chronic myeloid leukaemia
There is uncontrolled clonal proliferation of myeloid cells (basophils, eosinophils and neutrophils)
What would the FBC and bone marrow aspirate from someone with CML look like?
- Very high WBCs with whole spectrum of myeloid cells
- Low Hb
- Hypercellular aspirate
What chromosome is present in >80% of people with CML?
Philadelphia chromosome.
What is the treatment for CML?
Oral imatinib - tyrosine kinase inhibitors
What is ALL?
Acute lymphoblastic leukaemia
Uncontrolled proliferation of immature lymphoblast cells.
What is the treatment for ALL?
- Blood / platelet transfusions
- Prophylactic antimicrobials
- Allopurinol (prevents tumour lysis syndrome)
- IV fluids through Hickman line
- Chemotherapy
- Marrow transplant
What is CLL?
Chronic lymphocytic leukaemia
Proliferation of B lymphocytes leading to the accumulation of mature B cells that have escaped apoptosis
What is the treatment for CLL?
- Do nothing (cancer may regress)
- Chemotherapy / radiotherapy
- mAb - human IV immunoglobulins
- Bone marrow transplant.
Name the 3 broad categories of red cell disorders.
- Haemoglobinopathies.
- Membranopathies.
- Enzymopathies.
What is normal adult haemoglobin (HbA) made of?
Haem + 2 alpha chains + 2 beta chains
What is foetal haemoglobin (HbF) made of?
Haem + 2 alpha chains + 2 gamma chains
What is haemoglobin S (HbS)?
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?
A haemoglobin disorder of quality.
HbS polymerises -> sickle shaped RBC.
What is the advantage of being a carrier of sickle cell disease?
Carriage offers protection against falciparum malaria.
Describe the inheritance pattern of sickle cell disease.
Autosomal recessive.
Sickle cell disease is homozygous SS.
If both parents are carriers of the sickle trait. What is the chance that their first child will have sickle cell disease?
Their offspring have a 1/4 chance of being affected with a sickle cell disease. (50% chance of being a carrier).
How long do sickle cells last for?
5-10 days - this explains why sickle cell disease is described as haemolytic.
Give 4 acute complications of sickle cell disease.
- Very painful crises (due to vaso-occlusion and avascular necrosis)
- Stroke in children (CNS infarction)
- Cognitive impairment (CNS infarction)
- Acute chest syndrome (caused by infections, fat emboli from necrotic bone marrow, and pulmonary infarctions)
Give 6 chronic complications of sickle cell disease.
- Renal impairment (chronic tubulointerstitial nephritis)
- Pulmonary hypertension.
- Joint damage.
- Spontaneous abortion (impaired placental blood flow)
- Retinopathy, vitreous haemorrhage, retinal detachments
- Hepatomegaly, liver dysfunction (due to trapping of sickle cells)
- Anaemia (chronic haemolysis)
How can you diagnose sickle cell disease?
Blood count - raised reticulocyte count
Blood films - sickled erythrocytes, positive sickle solubility test
Hb electrophoresis - 80%+ HbS and absent HbA
Describe the treatment for sickle cell disease.
How do you treat painful attacks?
- Transfusion (to treat acute chest syndrome, acute anaemia, stroke, HF)
- Hydroxycarbamide (to increase HbF concentration)
- Stem cell transplant.
- Avoid precipitating factors (e.g. cold, infection, dehydration) - prophylaxis vaccines
- Folic acid
Treat painful attacks with IV fluids, analgesia, oxygen and antibiotics (if required)
What is the significance of parvovirus for someone with sickle cell disease?
Parvovirus is a common infection in children.
It leads to decreased RBC production and can cause a dramatic drop in Hb in patients who already have a reduced RBC lifespan.
This can be dangerous for someone with sickle cell.
What is thalassaemia?
A haemoglobin disorder of quantity.
There is reduced synthesis of one or more globin chains, leading to reduced RBC
Describe beta thalassaemia
- Very few beta chains
- Excess alpha chains
- Alpha chains combine with delta and gamma chains, resulting in increases HbA2 (Hb delta) and HbF (Hb gamma)
- Caused by point mutations, resulting in production of highly unstable beta globins
What are the clinical classifications of beta thalassaemia?
- Thalassaemia major.
- Thalassaemia intermedia.
- Thalassaemia minor (carrier / heterozygote).
Describe beta-thalassaemia minor.
- Heterozygote
- Asymptomatic
- Anaemia is mild / absent
- Hypochromic microcytic RBCs with LOW MCV
- Can be confused with iron deficiency, but distinguished since serum ferritin and iron stores are normal
- Hb electrophoresis shows raised HbA2 and HbF
Describe beta-thalassaemia intermedia
- Those who are symptomatic with moderate anaemia, but do not require regular transfusions
- Splenomegaly
- Bone deformities
- Recurrent leg ulcers
- Gallstones
- Infections
Describe beta-thalassaemia major
- Presents in children (<1yr) with homozygous beta-thalassaemia
- Failure to thrive and recurrent bacterial infections
- Severe anaemia from 3-6 months (when switch from gamma to beta chain production should occur)
- Extramedullary haematopoiesis, resulting in hepatosplenomegaly and bone expansion, leading to thalassaemic faces
- Life-long transfusion dependant
- Hypertrophy of ineffective bone marrow, thus bone abnormalities
- ‘Hair-on-end’ skull x-ray due to increased marrow activity
- Very low MCV - microcytic
- Irregular hypochromic RBCs
- Normal serum ferritin
Why is it important to monitor iron levels in someone with beta thalassaemia major?
There is a risk of iron overload from the regular trasnfusions.
Excess iron will be deposited in various organs (e.g. the liver and spleen) and cause fibrosis.
Describe the inheritance pattern for membranopathies.
Autosomal dominant.
Name 2 common membranopathies.
- Spherocytosis.
- Elliptocytosis.
Briefly describe the physiology of membranopathies.
Deficiency of red cell membrane proteins caused by genetic lesions
What are enzymopathies?
Enzyme deficiencies lead to shortened RBC lifespan.
Name a common enzymopathy.
G6PD deficiency.