Wk3 - Haematology Flashcards
Site of haemopoiesis in foetus, infants and adults
Foetus:
0-2 months - yolk sac
2-7 months - liver, spleen
5-9 months - bone marrow
Infants: Bone marrow (all bones - not just axial skeleton)
Adults: Bone marrow (vertebrae, ribs, sternum, skull, sacrum, pelvis, ends of femurs)
Pluripotent stem cell divides to
Myeloid stem cell and lymphoid stem cell
Haemopoietc stem cell characteristics
Self renewal capacity
Unspecialised
Ability to differentiate (mature)
Quiescent (i.e. not undergoing cell cycle, in in G0) - only undergoes occasional cell division
Where are haemopoietic stem cells found?
Bone marrow
Peripheral blood after treatment with G-CSF (stem cells can be obtained out of bone marrow by G-CSF)
Umbilical cord blood
Haemopoietic stem cells can underrgo one of 3 things,,,
Self-renewal (identical copy)
Apoptosis
Differentiation
Haemopoietic stem cells can undergo one of 3 types of differentiation
1) Symmetrical division, contraction of stem cell numbers
2) Asymmetrical division, maintenance of stem cell numbers
3) Symmetrical division, expansion of stem cell numbers
Stroma = ?
The bone marrow microenvironment that supports the developing haemopoietic cell
Rich environment for growth and development of stem cells.
Stromal cells supported by an extracellular matrix.
BOne marrow microenvironemnt contains a number of different cells…
e.g. macrophages, fibroblasts, endothelial cells, fat cells, reticulum cells
These produce e.g. collagen, fibronectin, laminin, proteoglycans
What site is bone marrow aspirate taken from?
Iliac crest
Hereditary conditions impairing bone marrow function?
Thalassaemia, sickle cell anaemia, Fanconi anaemia, Schwachman-Diamond syndrome Hereditary leukaemia (very rare)
Acquired conditions impairing bone marrow function
Aplastic anaemia, leukaemia, myelodysplasia, myeloproliferative disorders, lymphoproliferative disorders, metastatic malignancy e.g. breast, infections e.g. TB/HIV, drugs and toxins, chemotherapy, haematinic deficiency
Principles of leukaemogenesis
HSC–> LSC –> Clonogenic leukemia cells –> non-clonogenic leukaemia blast cells
A multistep process
Neoplastic cell is a haemopoietic stem cell or early myeloid or lymphoid cell.
Dysregulation of cell growth and differentiation (associated with mutations)
Proliferation of the leukaemic clone with differentiation blocked at an early stage.
Haematological malignancies and pre-malignant conditions are termed ___ if they arise from a single ancestral cell
‘clonal’
Chronic myelogenous leukemia
Increase in WBCs (from myeloid lineage)
CML is acuased by BCr gene on chromosome 22 translocating to Abl gene on chromosome 9 –> this creates a new type of chromosome - Philadelphia chromosome.
This leads to increased pleuripotent stem cell production from bone marrow –> increased WBC
Chronic myelogenous leukemia
Increase in WBCs (from myeloid lineage)
CML is caused by BCr gene on chromosome 22 translocating to Abl gene on chromosome 9 –> this creates a new type of chromosome - Philadelphia chromosome.
This leads to increased pleuripotent stem cell production from bone marrow –> increased WBC
Myeloproliferative disprders =
clonal disorders of haemopoiesis leading to increased numbers of one or more mature blood progency
Classical MPDs (myeloproliferative disorders) are…
Polycythaemia rubrae vera (inc. RBCs)
Essential thrombocytosis (inc. platelets)
Myelofibrosis (inc. fibrous tissue)
Myeloproliferative disorders are variably associated with what mutation
JAK2V617F (point mutation) and calreticulin mutation
Myeloproliferative disorders have potential t transform into
AML
Clinical features of essential thrombocytosis
50% cases carry JAK2v617F, 50% carry calreticulin mutation.
Continuum with PRV Thrombotic complications Haemorrhagic complications Splenomegaly Transformation to PRV or myelofibrosis Leukaemic transmation in 3%
Treatment of essential thrombocytosis
Low risk (<40y with no high risk features e.g. diabetes) - aspirin or anti-platelet agent
Intermediate risk (40-60y with no high risk features) - aspirin +/- hydroxycarbamide)
High risk (>60y with thrombotic risk factors): 1st line = hydroxycarbamide + aspirin 2nd line = anagrelide + aspirin IFN alpha -usefu with pregnancy Busulphan (e.g. someone not independent) JAK2 inhibitors e.g. ruxolitinib
Describe JAK2 inhibitors
JAK2 mutations result in continuous activation of JAK receptor regardless of ligand binding
Ruxolitinib - inhibits JAK1 and 2, reduces splenomegaly, main side effect is thrombocytopenia, results in jak2 pos and neg patients
Describe myelodysplastic syndromes (MDS)
Characterised by dysplasia and ineffective haemopoiesis
May be secondary to previous chemotherapy or radiotherapy.
May have increased myeloblasts.
Often associated with acquired cytogenic abnormalities e.g. monosomy 5, monosomy 7, trisomy 8.
Majority characterised by progressive bone marrow failure
Some progress to AML
MDS clinical features
Predominantly affects the elderly
Majority present with fatigue due to anaemia
Fewer present with infections or bleeding or FBC
MDS management
Supportive caare - blood and platelet .transfusion.
Growth factors - Erythropoietin +/- granulocyte colony stimulating factor (G-CSF).
Immunosupression - anti-thymocyte globulin (ATG).
Low dose chemotherapy - e.g hydroxycarbamide, low dose cytarabine.
Demethylating agents - e.g. azacytidine, an epigenetic therapy.
Intensive chemotherapy - AML type chemotherapy.
Allogenic stem cell transplantation - only in selected patients
Features of fanconi anaemia
How is aplastic anaemia diagnosed?
Fanconi anaemia makes up 10-20 % of aplastic anaemia cases
Autosomal recessive inheritance Characteristics: Somatic abnormalitis e.g. skeletal deformities. Bone marrow failure Short telomeres Malignancy Chromosome instability
Features: microphthalmia GU malformations GI malformations Mental retardations Mental retardation Hearing loss CNA e.g. hydrocephalus
Currently 7 genetic sub-types FANCA-G
Aplastic anaemia diagnosed - definitively diagnosed through bone marrow biopsy –> most stem cells are gone and replaced by fat
Treatment of fanconi anaemia
Main cause of mortality is premature bone marrow failure
Gold standard therapy is allogenic stem cell transplant
Corticosteroids
Androgens (oxymethalone) - to increase blood counts
Lifetime surveillance for secondary tumours
Possibility of gene therapy in future where faulty FANC gene is replaced
Types of stem cell transplant
Autologous - uses patients own stem cells
Allogenic - stem cells come from a donor. - 5 types:
1. Syndeneic - identical twins
2. Allogenic sibling - HLA identical
3. Haplotype identical - half matched family member. Usually a parent or half matched sibling
4. Volunteer unrelated (VU) - akak matched unrelated (MUD)
5. Umbilical cord blood
Main indications for autologous stem cell transplant
relapsed Hodgkin’s disease, non Hodgkins lymphoma and myeloma, chronic leukaemia
Preparation for autologous transplant
Patients receive growth factor (G-CSF) +/- chemotherapy to make the stem cells leave the bone marrow so they can be collected from the blood.
Mozobili has been used to collect stem cells in patients that have failed to mobilise
Features of umbilical cord blood transplant
Blood stem cells collected from umbilical cord and placenta.
Cells are tissue typed and frozen in liquid nitrogen in cord blood banks for future use
Advantages and disadvantages of umbilical cord transplant
Advan: more rapidly available in VUD, less rigorous matching to patient type of patient as immune system naive
Disadvan: if relapse, cannot go back for DLI
Describe graft versus host disease (GvHD)
Can happen in patients who have receieved an allogenic transplant. The new donor’s immune system recognises the host’s body as ‘foreign’ and start to attack it.
Most commonly manifests as a skin rash, jaundice or diarrhoea
What are the 2 types of GvHD
Acute GvHD - occurs within the first 100 days of the transplant
Chronic GvHD - occurs after first 100 days of transplant
GvHD is usually treated with …
immunosuppressive agents
GvL (graft vs leukaemia effect)
the same cells which cause GvHD also attack remaining leukaemic cells. GvL is very effective, especially in patients where a good remission has been difficult to maintain. Can also work in other blood cancers such as lymphoma and myeloma.
Minimising GvHD carries an increased risk of relapse.
In an autologous transplant there is no GvHD and therefore no GvL resulting in a greater risk of a relapse.
The challenge is to minimise GvHD and maximise GvL.
Anaemia = ? Polycythaemia = ?
Know about aplastic anaemia
Too little blood
Too much blood
Aplastic anameia - This is damage to haemopoietic stem cells, resulting in deficiency of all 3 blood cell types –> Pancytopenia (thrombocytopenia, leukopenia, anaemia)
1 molecules of Hb contains
Describe the requirements of normal red cell production
4 globin chains (2 alpha, 2 beta)
4 haem groups
Erythropoietin - drive for eryhtropoiesis Genes for the process Iron Vitamin B12 Folate and other minerals Functioning bone marrows No inc loss or destruction of RBCs
Transferrin
Involved in iron transport is a glycoprotein Synthesised in hepatocytes Dec. iron = inc. Tf Inc. iron = dec. Tf 2 iton binding sites. 30% saturated with Fe Tf delivers iron to all tissues, erythroblasts, hepatocytes, muscle etc.
RES storage and recycling
Effete red blood cells are removed by the macrophages of the reticuloendothelial system (RES) (RBC lifespan 120d)
The RES stores 500mg of iron
RES iron is stored in ferritin/haemosiderin
RES releases iron to Tf in plasma
Tf-iron taken up via Tf receptors on erythroblasts, hepatocytes etc.
Hepcidin
Is the ‘low iron’ hormone - it reduces levels of iron in plasma. Hereditary haemochromotosis dt loss of Hepcidin.
Hepcidin binds ferroportin and degrades it - reducing iron absoprtion (enterocyte) and decreasing iron release from the RES.
Hepcidin is synthesised in the liver (requires expression of HFE)
4 causes of hypochromic microcytic RBCs
IDA (not enough haem)
Thalassaemia (not enough globin)
ACD
Sideroblastic anaemia (particularly congenital SA)
iron and transferrin saturation levels
Normal - 30%
IDA - <15%
Low serum ferritin always indicates …
low RES iron stores
How can IDA occur with normal serum ferritin levels
In presence of tissue inflamamtion (RA & IBD)
Signs of IDA
Diagnosis of IDA
Koilonychia
Atrophic Glossitis
Angular stromatitis
Oesophageal web (plumer vinson syndrome)
Hypochromic microcytic RBCs
<15% saturation transferrin
Low serum ferritin –> always indicates low RES iron stores
Causes of IDA
Dietary - premature neonates, adolescent females
Malabsorption
Blood loss
Levels of menorrhagia
> 80mls blood/period
Golden rule of IDA
IDA in males and post-menopausal females is due to F=GI blood loss until proven otherwise
Young women; menstrual blood loss +/- pregnancy
Iron replacement in IDA
Ferrous sulphate
Ferrous Gluconate
IV iron (when- intolerant to oral iron, complicance, renal anaemia & Epo replacement
Describe Anaemia of Chronic Disease (ACD)
Failure of iron utilisation
iron trapped in RES
Causes - infection, inflammation, neoplasia
Pathophysiology ACD = Iron is trapped in REs within macrophages, causing a reduced Epo response. This results in depressed marrow activity –> cytokine marrow depression
Anaemia of CRF = ACD + dec. Epo
Lab values in ACD
MCV/MCH N/dec. - normochromic normocytic or hypochromic microcytic RBCs ESR - inc. (RBC Rouleaux) Ferritin - N/inc. Iron - dec. TIBC - dec.
Causes of ACD
RE Iron blockade; iron trapped in macrophages; raised levels of Hepcidin
Reduced Epo response
DEpressed marrow activity; cytokine marrow depression
Treatment of ACD
Treat underlying disorder
B12/folate is essential for…
DNA synthesis and nuclear maturation.
Required for all dividing cells, deficiency noted first in red cells
DEficiency in B12/folate
results in megaloblastic anaemia intitially, but will effect other organs
B12 (Cobalamin) is necessary for 2 processes -
Methylation of homocysteine to methionine
Methylmalonyl-CoA isomerisation
Dietary sources of B12
Meat (esp. iver and kidney), small amount in dairy products
Normal western diet 5-30ug/day
Daily requirement - 1ug/day
Describe B12 absorption
B12 ingested (in form of animal protein).
Gastric pariteall cells in fundus/body produce Intrinsic factor.
B12 released by enzymes/acid in sotmach and duodenum.
Intrinsic Factor binds to B12 in duodenum/jejunum.
IF-B12 complex binds to cubulin (specific receptor in ileum) - is absorbed in ileum.
B12 absorbed and binds to transcobalamin in the blood.
B12 stored for …
3-4 years
Folate - dietary stores, absorption, stores
Green veg (destroyed by cooking)
Absorption - mostly small bowel. No carrier molecule required.
Stored - few days only - quickly used up if increased demand (ie increased cell turnover)
Clinical B12 deficiency - blood abnormalities and neurological manifestations
Megaloblastic anaemia (leucopenia, thrombocytopenia)
Bilateral peripheral neuropathy or demyelination of the posterior and pyramidal tracts of spinal cord. (likely related to problem with homocysteine -> methionine
Clinical folate deficiency - blood abnormalities and growing fetus
Megaloblastic anaemia (leucopenia and thrombocytopenia)
1st 12 weeks - deficiency can cause neural tube defects
Signs and symptoms of B12/folate deficiency
Symptoms of anaemia/cytopenia:
Tired - macrocytic/megaloblastic anaemia (common); easy bruising - thrombocytopenia (rare)
Mild jaundice - haemolysis
Neurological problems - nerve disturbance as a result of B12 def - subacute combined degeneration of cord
Causes of folate deficiency
Dietary
Extensive small bowel disease - coeliac, sever Crohns
Increased cell turnover - haemolysis, severe skin disorders, pregnancy
Components of HbA and HbF
Develop a logical approach to the investigation of a patient with anaemia
HbA - 2alpha, 2 beta
HbF - 2alpha, 2gamma
Is the information new? - helps determine congenital or acquired
Any clues in the history? - blood loss, diet, chronic disease, family history, medication etc.
Examination findings - angular stromatitis, splenomegaly, lymphadenopathy, abdominal passes
Blood film
Coombs test - this is used to test for autoimmune haemolytic anaemia:
Direct Coombs test - This is used to detect antibody on RBC surface. Blood sample is taken and RBCs washed to removed own plasma, which they are then incubated with anti-human globulin. If this produces agglutination of RBCs, positive test –> shows AIHA or HDN
Indirect Coombs test - This is sued to detect RBS antibodies within the plasma during prenatal testing of pregnant women, and in testing blood prior to blood transfusion. Serum extracted from blood sample and incubated with RBCs of a known antigenicity. If agglutinaiton occurs, positive test
Provide examples of diseases causing anaemia
Thalassaemias =
Thalassaemias, Haemoglobin chain variants, Haemolytic anaemia (congenital and acquired (warm and cold type))
relative lack of normal globin chains due to absent genes
Clinical significance of alpha thalassaemia
Missing one gene - mild microcytosis
Missing 2 genes - micorcytosis, increased red cell count and sometimes very mild (asymptomatic) anaemia
Missing 3 genes - significant anaemia and bizarre shaped small red cells - Haemoglobin H (HbH) disease
Missing 4 genes - incompatible with life (need alpha chains for fetal haemoglobin) - alpha thalassaemia major
Featurs of Hbh disease
Missing 3 alpha genes
Lack og alpha chains -> excess beta chains
Beta chains end up joining together (HbH)
Blood transfusion require during periods of stress
Hb variable 65-75g/l
Features of beta thalassaemia major
missing both beta globin genes.
Autosomal recessive
Unable to make adult haemoglobin (HbA)
Significant dyserythropoiesis (poorly functioning RBCs)
Hypochromic, will have splenomegaly and CF
Maxillary prominence
Thicker skull
Presentation and treatment/management of beta thalassaemia major
Don’t feed well, falling off centile, smaller stature
Transfusion dependent from early life (first couple of years)
Ion overload has major effect on life expectancy
pathogenesis of sickle cell disease
Chromosome 11:
Single amino acid substitution on B globin gene at position 6
Glutamine>Valine = Hb S
(Glutamine>Lysine = HbC)
HbS = 2 alpha + 2 beta (sickle) = (a2bs2)
Describe how sickle cell anaemia is described as a multisystem disease
Brain - stroke
Lungs - acute chest syndrome, pulmonary hypertension
Bones - Dactilytis, osteonecrosis
Spleen - hyposlenic
Kidneys - loss of ocncentration, infartion
Urogenital - priapism - chronic, acute
Eyes - vascular retinopathy\Placenta - IUGR/fetal loss
Treatment of sickle cell anaemia
Prevent crissi - hydration, analgesia, early intervention, prophylactic vaccination and antibiotics, folic acid
Prompt manageemnt of crises - oxygen, fluids, analgesia, antibioticis, transfusion/red cell exchange
Bone marrow transplantation
Definition of haemolytic anaemia
Anaemia related to reduced RBC lifespan
No blood span
No haematinic deficiency
3 reasons for congenital haemolytic anaemia
- Abnormalities of RBC membrane - hereditary spherocytosis - autosomal dominant, jaundice, splenomegaly, give supply of folic acid
- Haemoblobinopathies
- Abnormalities of RBC enzymes e.g. pyruvate kinase deficiency anaemia (autosomal recessive), glucose 6 phosphate dehydrogenase deficiency (x-linked)
3 reasons fro acquired haemolytic anaemia
- Autoimmune - warm type (IgG), cold type (IgM)
- Isoimmune - ahemolytic disease of newborn (HDN) (antibodies arise in mother & cross the placenta)
- Non-immune - fragmentation haemolysis (can be seen with Ecoli)
Treatment of Cold AIHA and warm AIHA
Cold - self limiting mycoplasma
Idiopathic - keep warm
Warm - stop and drugs, steroids, immunosuppression, splenectomy
What is leukaemia?
Difference between chronic and acute
Accumulation of abnormal leucocytes in marrow +/- blood +/- other tissues
Chronic - symptoms from accumulation of cells
Acute - symptoms from bone marrow
What are the 2 pre leukaemic conditions
MDS - myelo-dysplastic syndrome
MPD - myleo-proliferative disorders
Both clonal blood disorders
Features of MDS
Failure of effective haemopoiesis (low blood count)
Most common in elderly
‘Dysplastic’ blood and marrow appearances
Approx 25% rate of transformation to AML
Consequences of marrow failure
Low and high risk established by proportion of blast cells in marrow and cytogenic profile (MDS vs AML)
Features of MPDs
JAK2 mutation is prevalent
Effective haemopoiesis - too many platelets (essential thrombocythaemia) or too many red cells (&plts and WC) (polycythaemia Vera or primary polycythaemia) or too much fibrous tissue (&plts & WC) (Myelofibrosis)
Treatment of MPDs
Et & PRV - risk of vascular events (aspirin), cytoreduction (hydroxycarbamide, venesection or interferon)
Myelofibrosis - large spleen, systemic cymptoms, blood counts high or low, incurabel other than with SCT. New class of drugs - JAK2 inhibitors
Diagnosing acute leukaemia
Do blood count then blood film
- anaemia, neutropenia, thrombocytopenia, blasts
Bone marrow - Blast cells>20%
Flow cytometry
Karyotyping:
Standard cytogenics
t(15:17) M3 AML
t(8:21) M2 AML
What are the 3 choices for managing AML
- Intensive chemotherapy +/- SCT (<60-65 y/o)
Most young patients entered into trails
Bleeding, infection, hair loss, sterility, mucositis, psychological element.
Anthracycline and cytarabine based. Some only curable using allogenic transplant. - Low dose chemotherapy (>60-65)
- Supportive care only (older patients, major comorbidities, median survival 3-6 months)
Clinical presentation of ALL
The limping child
Purpuric rash
Unexplained, sometimes severe, bone pains
Management of ALL
Chemotherapy:
Anthracycline, Prednisolone, vincristine, cytarabine etc.
Initial aggressive therapy, then oral maintenance (1-2 years)
Management of acute leukaemia - supportive
Blood transfusion
Fresh frozen plasma - for coagulopathy/DIC
Platelet transfusion - purpura and bleeding, during fveer, sepsis, DIC
Antibiotics
Growht factors (G-CSF)
Granulocytes - refractory infections
Transplant procedures for acute leukaemia mostly for
Relapsed patients, refractory patients, poor risk disease in first CR
Age less than 60 yrs
Allogenic transplant done
Presenting features of chronic lymphocytic leukaemia (CLL)
More present in older patients Commonest leukaemia Most cases - patients are asymptomatic Lethargy, night sweats, weight loss (B symptoms) Symptoms of anaemia Lymphadenopathy Infection (as often quite immunosuppressed) Is often an incidental diagnosis
(CLL is reduction in B lymphocytes)
Clinical staging of CLL
A - <3 involved nodes - 10yrs survival
B - >3 involved nodes, liver, spleen - 7 yrs
C - Anaemia or thrombocytopenia - 2 yrs
Cytogenetics for CLL
Interphase FISH is useful
CLL with 17p deletion
Aggressive disease
Refractory to chemoherapy
Deletion 17p results in loss of p53
Patients may respond to steroids and antibiotics
B-cell tyrosine kinase inhibitors - new oral drugs - can kill p53 mutated cells
CLL - immune complications
Autoimmune haemolytic anaemia
Autoimmune thrombocytopenia
Treat with steroids
What is seen on blood film with AIHA (autoimmune haemoltic anaemia0
Spherocytes
Polychramasia
CML clinical presentation
May be asymptomatic
Fatigue, weight loss, night sweats, abdominal discomfort, splenomegaly (seen in most patients)
CML natural history
Chronic phase –> accelerated phase –> myeloid blast phase
What trasnlocation is a cause of CML
Translocation between chromosome 9 and 22 - creating BCrABl
–> Philadelphia chromosome
Diagnosis of CML
Blood film and clinical features
Molecular test on blood (BCR-ABL PCR/FISH)
Cytogenetic analysis (‘karyotype’) - to look for Philadelphia chromosome
If BCR-ABL negative - not CML!
Treatment for CML
Imatinib - a targeted therapy
2nd line - TKI inhibitors
What is the most common type of lymphoma?
Non-Hodgkins (85%)
Hodgkins (15%)
Presentation of lymphoma
Lymphadenopathy - painless, rubbery
Splenomegaly
B symptoms - night sweats, weight loss, unexplained fever
Anaemia
The site bone marrow biopsies are taken from - to aid diagnosis of lymphoma
Investigations of lymphoma
Posterior superior iliac spine
Investigations:
History - symptoms, duration of symptos, B symptoms
Clinical examination - lymph nodes, splenomegaly
Blood tests - FBC, U&Es, LFTs, Ca, ESR, LDH
Imaging tests - CT scan, PET/CT scan
Bone marrow biopsy - aspirate and trephine
Additional tests (may be required pre treatment) - echocardiogram, pulmonary function tests
Staging of lymphoma
I: single lymph node group
II: more than one lymph node group SAME side of diaphragm
III: lymph node groups BOTH sides of the diaphragm (includes spleen)
IV: extranodal involvement e.g. liver, bone marrow
A or B added to signify absence or presence of B symptoms
Early stage - 1 or 2A
Advanced stage - 2B or 3 or 4
Most HL diagnosed at early stage
Most NHL diagnosed at advanced stage
Non-hodgkins lymphoma - when T or B cell affected
B cell (>90%) T cell (10%)
CD20 - antigen expressed on B-lymphocytes
Target for treatment with the monoclonal antibody Rituximab
Features of follicular lymphoma
Low grade lymphoma
Resemblance to normal germinal centres
Characterised by transloations involving BCL2 gene (upregulation of BCL2 - an anti-apoptotic protein)
Slow growth but reduced cell death (apoptosis)
Is a B cell lymphoma
Usually incurable
Predominantly affects adult
Treatment of follicular lymphoma
Treatment aimed at alleviating symptoms Early stage (1A, some 2A) -> localised radiotherapy
Advanced stage:
Asymptomic, no end organ compromise -> watch and wait
Symptomatic and/or organ compromise -> immunochemotherapy - Rituximab and chemo
Followed by maintenance Rituximab every 2 months for 2 years
Features of diffuse large B-cell lymphoma
high grade lymphoma
Resemblance to activated B-cells
Associated with various translocations and geentic abnormalities; complex karyotype.
High proliferation fraction, variable rate of cell death
Commonest subtype of NHL
Most cases BCL-6 positive but variable CD10 and BCL2 expression.
Mostly adults but wide age range and can occur in children
Aggressive but curable in >50%
Presentation of diffuse large B cell lymphoma
Lymphadopathy - usually rapidly enlarging LN mass
Extra-nodal presentation also common - GI tract, skin, bon, CNS etc.
Night sweats and weight loss
Treatment of DLBCL
Aggressive chemotherapy
Early stage (1A) - R-CHOP x 3
All other stages - R-CHOP x 6
R-CHOP chemotherapy =
Rituximab, cyclophosphamide, Adriamycin, Vincristine, Prednisolone
Burkitt lymphoma - features
High grade lymphoma
Resemblence to proliferating centre cells
Characterised by translocations involving MYC gene and IG gene (but simple karyotype)
MYC gene drives proliferation but is alsoo linked to apoptosis - rapid proliferation of neoplastic cell and high rate of apoptosis.
Very high rate of proliferation
High rate of cell death (apoptosis) - Tumour Lysis Syndrome is an issue
Presentation of Burkitt lymphoma
Short history, marked B symptoms, rapidly growing tumours.
Most cases present with extranodal disease - jaw and facial bone, ovaries, kidneys, breast, lymph nodes and bone marrow
Describe features of classic Hodgkin lymphoma
Lymphoid neoplasms affecting lymph nodes (unlike NHL do not present at extranodal sites).
High grade lymphoma with prominent component of reactive cells.
Neoplastic cell resembles atypical activated B-cell as seen in some viral infections (e.g. EBV).
Characterised by strong expression of CD30 and loss of some B-cell antigens.
2 main subtypes:
Nodular lymphocyte predominant Hodgkin lymphoma (6% of HL)
Classic Hodgkin lymphoma (94% of all HL)
Presentation of Hodgkins lymphoma
Bimodal age incidence.
Usually presents with painless lymphadenopathy - neck lump, cough, shortness of breath.
May have B symptoms
Itch may precede diagnosis for many months
Treatment of HL
Very effective - high cure rates
Early stage -> usually combined modality Rx ie chemotherapy followed by radiotherapy.
Advanced stage -> chemotherapy
ABVD - adriamycin, bleomycin, vinblastine, dacarbazine
Describe features of plasma cell myeloma
Neoplasm of mature plasma cells.
Express plasma cell markers e.g. CD138.
show aberrant phenotype e.g. CD19 negative, CD56 positive, Cyclin D1 positive, light chain restriction
Presentation of plasma cell myeloma
Non-specific symptoms - backache, fatigue, symptoms from hypercalcaemia, recurrent infections, renal impairment
In most myeloma patients, abnormal plasma cells produce an abnormal ‘monoclonal protein; called a
paraprotein or ‘M’ protein
- 5 different types (IgG, A, M, D, E)
- IgE very rare
- IgM rare (more commonly associated with lymphoma
What is the classic triad of myeloma
Increased plasma cells in bone marrow
Clonal imunoglobulin or paraprotein
Lytic bone lesions
Diagnosing myeloma
Blood tests - FBC, ESR, U&Es, Ca++, SFLC
Urine tests - to look for light chains in urine - Bence-Jones protein
Bone marrow aspirate
imaging
tion of featuresDiagnosis of plasma cell myeloma is based on a combina
Neoplastic plasma cells in bone marrow >=10% of total cells plus at least one of the following:
End-organ dmaage attributable to the plasma cell proliferation (CRAB criteria) - hyperclacaemia, renal insufficiency, anaemia, bone lesions: >=1 lytic lesion on skeletal x-ray, CT or PET/CT
Biomarkers of malignancy
Treatment of plasma cell myeloma
Asymptomatic myeloma (smouldering) -> watch and wait Symptomatic (determined by CRAB) criteria) -> requires treatment
Chemotherapy usually including a steroid and thalidomide
Radiotherapy -> e.g. severe bone pain
Supportive therapy - bisphosphonates - reduce pain, hypercalcaemia and reduces need for radiotherapy; Blood transfusion/EPO; surgery; interventional radiology
Prognosis of myeloma
incurable
Variable - median 5.5 years
Lymphoma is malignancy derived fro…
lymphocytes, either from B-lymphocytes, T-lymphocytes or natural killer cells.
Unlike leukaemia it generally presents with a tumour mass
Risk factors for lymphoma
Immunosuppressive disorders/treatments - organ trasnplant, HIV
Infections - EBV, h.pylori (MALT lymphoma od stomach)
Age - increased chance of genetic change
Having a close relative with lymphoma
Lymphoma arises as a consequence of ___ damage
DNA damage
Altered expression subverts normal regulation of growth:
Cell birth/division (proliferation) - usually increased and autonomous
Cell death (apoptosis) - often reduced
Difference between leukaemia and lymphoma
Leukaemia - widespread involvement of bone marrow and peripheral blood
Lymphoma - discrete tissue masses
There are 4 broad categories of lymphoid neoplasms based on cell lineage and stage of development at which neoplasms arise i.e.
Precursor B-cell and T-cell neoplasms (mostly leukaemias)
Mature B cell and T-cell neoplasms (mostly lymphomas)
Where is the malignancy in plasma cell myeloma based on?
What type of immunoglobulin is it associated with?
Bone marrow
Cloncal immunoglobulin production (usually IgG)
General categories of lymphoma
Non-Hodgkins (75%) - Nodal (60%), extranodal (40%)
Hodgkins (25%)
How can u differentiate between low grade and high grade lymphoma on immunohistochemistry
Ki67 is a protein expressed by cells in cell cycle (S-phase) i.e dividing or proliferating cells express this protein.
High grade - lot stained
What do activated platelets express on their surface membrane
Phospholipids
Describe primary and secondary haemostasis (briefly)
Primary - recruitment of platelets (platelet plug)
Secondary - activation of coagulation factors (initiation, propagation, thrombin generation, fibrin clot)
Occurs simultaneously
How to assess primary and secondary haemostasis
Primary - invivo - bleeding time; ex vivo - FBC, platelet function
Secondary - PT (stimulates activation via the extrinsic pathway), APTT (stimulates activation via the intrinsic pathway (activated through collagen)), TCT (measurement of conversion of fibrinogen to fibrin clot), individual coagulation factor assays
What are the 3 types of antithrombotic agents
Anticoagulants (inhibit one or several components of cascade to inhibit formation of fibrin clot) e.g. heparin, warfarin
Fibrinolytic agents (enhance lysis of fibrin clot)
Anti-platelet agent - inhibit platelet activation or aggregation
What factors does Warfarin act on
IIa, VIIIa, IXa, Xa
Mechanism of action of heparin
Mixture of glycosaminoglycans of differing polysaccharide chain length. Particularly acts on IIa and Xa Heparin does not cross placenta Short half life Administered parenterally
Side effects of heparin
HIT (heparin induced thrombocytopenia)
Osteoporosis
Hyperkalaemia
The effects are less with LMWH than with UFH
LMWH vs UFH
LMWH have superior pharmacokinetic profile
LMWH have safer side effects.
LMWH have higher drug costs but lower consumable costs and do not require monitoring
LMWH can be used in out-patients
What is inhibited by warfarn
VKOR - Vitamin K Oxide Reductase
Is an oral vitamin K antagonist –> dysfunction factors II, VII, IX, X
What is haematinic?
folic acid
Hyposplenism does not cause increased risk of?
a) Meningococcus
b) Pneumococcus
c) Haemophilus
d) E Coli
e) Malaria
e.coli
Diagnosis of baby anaemia
a. Alloimmune anaemia of the foetus
b. Rhesus haemolytic disease of the newborn
c. α-thalassaemia minor
d. β-thalassaemia major
e. Vitamin K deficiency
Rhesus haemolytic disease of the newborn
Management of acquired warm type haemolytic anaemia
- Corticosteroids - Prednisolone (60-100mg per day, subsequenlty reducing). Haemolysis should be dramatically reduced in 80% of patients within 3 weeks
- Blood transfusion - transfusion of packed red cells may be required depended on the patients symptoms
- Folic acid - such may be the demands for red cell production that folic acid stores may be compromised and supplementation may be required in sever cases
- Splenectomy - - in patients whose anaemia is refractory to prednisolone, or in those who require long term high dose therapy to suppress the haemolytic state. Such patients are liable to develop the serious complications of steroid therapy
Risks of splenectomy
The spleen is an important organ in sieving out micro-organsims including streptococcus pneumoniae, Haemophilus influenzae and neisseria meningitis
Such organisms can cause overwhelming post splenectomy infections (OPSI).
Patients must be vaccinated against these organisms pre-operatively. In addition life long antibiotic prophylaxis (penicillin V) is recommended.
Patients must be informed of this risk, understand they require antibiotic in the event of an infection and carry a ‘splenectomy’ card with them at all times.
The mechanism of destruction of RBCs in haemolytic anaemia is of 2 main types:
Intravascular - the destruction fo red cells occuring directly in the circulation
Extravascular - occurring within the reticuloendothelial system of the spleen, liver and bone marrow
Features of intravascular anaemia
can occur by mechanical trauma to the red cell - so called red cell fragmentation.
Intravascular haemolysis can also follow ABOincompatible blood transfusion (anti-A and Anti-B and IgM antibodies).
Other causes include malaria and Cold (IgM) autoantibodies. Cold autoantibodies cause the RBCs to agglutinate on the blood film. Cold antibody is difficult to treat. The patient must be advised to keep warm as the antibody only fixes to the RBCs in colder parts of the body i.e. cold hands etc.
Causes of cold autoimmune haemolytic anaemia (usually IgM antibodies)
a. Primary (idiopahtic)
b. Secondary including:
Infection-Mycoplasma pneumoniae
Infectious mononucleosis (Glandular fever)
Lymphoproliferative disorders
Main laboratory findings in intravascular haemolysis are
- Anaemia, reticulocytosis and raised unconjugated bilirubin
- Haemoglobinaemia and haemoglobinuria
- Haemosiderinuria
Features of extravascular haemolysis
Extravascualr is more common than intravascualr and occurs in the reticuloendothelial system, particularly the spleen. This type of haemolysis is often related to the production of ‘warm’ (incomplete) antibodies, usually IgG
The IgG attaches to the red cell antigen and damages the RBC membrane. The damaged RBCs become spherocytic and are phagocytosed by the RES, particularly the spleen. As a result the spleen enlarges. A positivedirect antiglobulin test indicates the presence of antibodies (or complement) on the RBC surface. Serum bilirubin is usually elevated and is of the unconjugated variety (hence alcoholic jaundice)
Causes of warm type AIHA
Primary (idiopathic) - 55-60%
Secondary causes include lymphoproliferative disorders such as chronic lymphocytic leukaemia and non-Hodgkins lymphoma, other neoplasms, SLE, other connective tissue disorders and drugs
B cell development
B cells are produced in bone marrow from commited stem cell progenitor
Mature B-cells circulate in peripheral blood and populate lymphoid and other organs
Interaction with antigen results in production of:
- Memory B cells
- Plasma cells
T cell development
T-cells originate in bone marrow from committed stem cell progenitor
Precursor T-cells migrate to thymus where they develop into mature T-cells
Mature T-cells circulate in peripheral blood and populate lymphoid and other organs
Mechanism of normal red cell destruction
Senescent red cells (100 + days are old) are destroyed by the cells of the reticuloendothelial system particularly in the spleen. Intravascular haemolysis (break down of red cells in the general circulation) plays a little or no part in red cell destruction under normal circumstances.
Mechanism of abnormal RBC destruction
Haemolysis may be defined as an increase in red cell destruction. The bone marrow has the ability to increase red cell production some six to eight fold. Thus the red cell span would have to be <15-20 days before anaemia develops.
The mechanism of destruction in the haemolytic anaemias is of 2 main types:
Intravascular - that is destruction of red cells occurring directly in the circulation
Extravascular - occurring within the reticuloendothelial system of the spleen, liver and bone marrow
Causes of intravascular haemolysis
Intravascular haemolysis can occur by mechanical trauma to the red cell - so called red cell fragmentation syndrome i.e. RBC breakdown by defective mechanical heart valves (RBC fragmentation also seen in HUS and MAHA).
Can also follow ABO compatible blood transfusion (anti-A and anti-B are IgM antibodies).
Other causes include malaria and cold (IgM) autoantibodies. Cold autoantibodies cause the RBCs to agglutinate on the blood film. Cold antibody haemolysis is difficult to treat. The patient must be advised to keep warm as the antibody only fixes to the RBCs in colder parts of the body i/e/ cold hands.
Explain the term ‘pancytopenia’
Reduce WBCs, Hb and platelets
Caused by variety of bone marrow disease. Can also be caused by hypersplenism and peripheral consumption of blood cells
Treatment of immune thrombocytopenia
Steroids - Prenisolone. Possibly splenectomy
No splenomegaly with ITP though
MOA of warfarin
Warfarin is a Vitamin K Antagonist.
- Inhibits Vitamin K epoxide reductase
- Prevents recycling of Vitamin K to reduced form after carboxylation of coagulation factors II, VII, IX, X.
- Prevents thrombus formation
MOA of heparin
Enhances activity of antithrombin III.
Antithrombin III inhibits thrombin
Heparins also inhibit multiple other factors of the coagulation cascade (particularly II and X)
This produces its anticoagulant effect.
Examples of Direct Oral Anti-Coagulants (DOACs)
Factors IIa inhibitor - Dabigatran etexilate
Factors Xa inhibitors - Rivaroxaban, Apixaban, Edoxaban
Pros and Cons of DOACs v Warfarin
Warfarin: Slow onset slow offset: results in smooth coagulation Requires very individualised dosing Required INR monitoring Many drug, food and alcohol interactions Renal impairment may increase bleed risk Rare s/e other than bleeding Rapid reversal with PCC and Vitamin K
DOACs:
Rapid onset and offset: anti-coagulated within 3h of 1st dose.
May require dose adjustment based on CrClRequires annual review
Few drugs and no food or alcohol interactions
Renal impairment may be a contra-indication
More minor s/e
Currently no rapid reversing agent
Causes of intravascular haemolysis
Can occur by mechanical trauma to the red cell - so called red cell fragmentation syndrome.
Can also follow ABO incompatible blood transfusion (anti-A and anti-B are IgM antibodies.)
Other causes include malaria and cold (IgM) autoantibodies. cOld autoantibodies cause the RBCs to aglgutinate on the blood film. Cold antibody haemolysis is difficult to treat - stay warm.
How is purpura caused?
Either due to platelet problem (usually thrombocytopenia) or vasculitis (i.e. Henoch Schonlein)
Purpura is seen in ALL
(Petechiae in AML)
Purpura can also be seen in immune thrombocytopenia (ITP)
What is DIC?
An acquired syndrome characterised by activation of coagulation pathways, resulting in formation of intravascular pathways, resulting in formation of intravascular thrombi and depletion of platelets and coagulation factors
Clinical history and examination consistent with DIC
Clinical history can include haematuria, oliguria, cough, dyspnoea, epistaxis, fever, delirium and coma.
Physical examination may reveal petechiae, ecchymosis, gangrene, mental disorientation, hypoxia, hypotension and GI bleeding
Diagnosis + Investigations for DIC
Diagnosis is based on presence of >=1 known underlying conditions causing DIC plus abnormal coagulation tests: decreased platelet count, increased prothrombin time, elevated fibrin-related marker (D-dimer/fibrin degradation products), and decreased fibrinogen level
Investigations - Lumbar puncture and blood culture
What is the bacteria responsible for meningococcal septicaemia (than can cause DIC - presenting with nuchal rigidity)
Neisseria meningitides
Treatment of meningococcal septicaemia causing DIC
IV antibiotics
Young female presents with exudation tonsillitis, cervical lymphadenopathy, slightly enlarged spleen and fever.
WBC shows atypical mononuclear cells.
What is the diagnosis?
What is the causative organism?
Describe the tests used to diagnose this condition.
Should she be given Amoxicillin while awaiting confirmation of diagnosis?
Infectious mononucleosis
EBV
Tests - Monospot test (Non-specific for Epstein Barr virus (EBV) infection. IgM antibodies agglutinate red cells from other species (sheep, horse, goat, bovine).
Commonly used Monospot test is a rapid qualitative slide agglutination test using horse or bovine red cells.)
- EBV titres
No amoxicillin will cause a rash in IM patients. If diagnosis is not clear the patient could be given simple Penicillin V to cover against potential Strep throat.
What is meant by the term heterophile antibodies?
They are agglutinins that appear in blood during IM (infectious mononucleosis) infection that react with sheep RBCs ie. they react across species barriers
A young male presents with a facial rash (butterfly distribution) and polyarthritis.
What is the likely diagnosis?
What is the likely cause of her prolonged PTT?
SLE
(systemic lupus erythematous)
Prolonged PTT - due to Lupus anticoagulant (LA) - an antiphospholipid antibody found in many people with lupus. LA increases your body’s ability to clot. DRBVT - to test for LA
Signs of Haemolytic Uraemic Syndrome
Bloody diarrhoea following travel. Anaemic Thrombocytopenic Uraemic Jaundices
Likely causative organism of haemolytic urease syndrome (following travel)
E. Coli 0157
What is the expected RBC appearance with HUS?
RBC fragmentation
Describe the Reed Sternerg (RS) cells
Large cels, abundant cytoplasm, 2 nuclear lobes each with prominent nucleolus, Owl’s eye appearance.
Found in Hodgkins lymphoma.
What are the different stages of lymphoma?
Stage I - single lymph node group
Stage II - more than one lymph node group on SAME side of diaphragm
Stage III - lymph node groups on BOTH sides of the diaphragm (includes spleen)
Stage IV - extranodal involvement e.g. liver, bone marrow.
A or B added after to signify absence or presence of B symptoms:
- Night sweats
- Weight loss
- Unexplained fever
Early stage = 1 or 2A
Advanced stage = 2B, 3, 4
What type of lymphoma is usually seen in older patients?
Non-Hodgkins lymphoma
An elderly woman is found to have painless cervical lymphadenopathy. She is otherwise well. She has rubbery nodes (1-2cm) in all areas and splenomegaly of 2 fingerbreadths.
High WBC, high haemoglobin, N platelets.
What is the likely diagnosis?
CLL
- Has monoclonal B cells
Hoes does CLL differ from CML
CLL does not change to acute leukaemia. It can progress but stays as CLL.
CML on the other hand has a tendency to change to acute leukaemia. Oddly CML can change to AML or aLL as well.
Staging of CLL
A <3 involved nodes (10yr survival)
B > 3 involved nodes, liver, spleen (7yr)
C - Anaemia or thrombocytopenia
Elderly man presents with sudden onset severe low back pain.
He has 3 months history of fatigue, but most recently developed polyuria and polydipsia.
Neurological examination normal.
What is the likely diagnosis?
What cells will be present in the bone marrow?
Why does the patient have raised calcium and back pain?
Multiple myeloma
Cells present in the bone marrow:
Abnormal plasma cells - derived from B lymphocytes.
>10 abnormal plasma cells = myeloma.
Back pain and inc. Calcium:
Myeloma causes lytic bone lesions with calcium release. Patient is likely to have had acute collapse of a vertebral body. Normal neurology would indicate that the spinal cord is intact. Patients are at risk of spinal cord compression.
Typical presenting complaints of a patient with multiple myeloma
CRAB:
C - Calcium elevation
R - Renal disturbance e.g. polydipsia, polyuria
A - Anaemia - fatigue, recurrent infections
B - Bone disease - back or rib pain
Why are urea and creatinine elevated in a patient with multiple myeloma?
Myeloma kidney - can result from hypercalcaemia, infection or damage to the kidneys by the paraprotein (monoclonal antibody).
Hypercalcaemia requires urgent IV rehydration
Why is the globulin level elevated in a patient with multiple myeloma?
What protein might you find in the urine?
The abnormal plasma cells release their immunoglobulins, producing an abnormal monoclonal antibody called the paraprotein (or M protein).
Protein in the urine - Bence Jones i.e. light chains
What cancers (non-haematological cancers) metastasise to bone?
LP Thomas Knows Best:
Lung Prostate Thyroid Kidney Breast
