Haem - ix

Question 1

Iron deficiency anaemia on blood film

Answer 1

Anisopoikilocytosis
Pencil cells
Hypochromic + microcytic

Question 2

Iron studies in anaemia of chronic disease

Answer 2

Decreased/Normal transferrin
Decreased TIBC
Normal transferrin saturation
Increased ferritin
Increased herpcidin 
Normocytic or mcrocytic anaemia

Question 3

Iron studies in iron deficiency anaemia

Answer 3

Increased transferrin
Increased TIBC
Decreased transferrin saturation
Decreased ferritin

Question 4

Hb electrophoresis to ix 2 diseases

Answer 4

Sickle cell disease

Thalassaemia

Question 5

Sickle cell anaemia ix

Answer 5

Hb electrophoresis
Blood film
Howell- Jolly bodies (usually removed by spleen, therefore also a marker of hyposplenism (elderly patient))
Sickle cells

Question 6

G-6-PD deficiency on blood film

Answer 6

Heinz bodies (occur in oxidative stress not specific to G-6-PD but most cases of oxidative stress are caused by G-6-PD deficiency) - active haemolysis
Bite cells - previous haemolysis

Question 7

Mutation classically assosciated with polycythaemia vera and myelofibrosis

Answer 7

JAK2 V617F

Question 8

E coli strain causing HUS

Answer 8

EHEC O157H7

Question 9

HUS ix

haemolytic uraemic syndrome

Answer 9

• FBC – anaemia, thrombocytopenia
• Blood film – schistocytes
• LDH – increased
• Haptoglobin – decreased
• LFTs - increased unconjugated bilirubin
• U+Es - increased Cr, low Na, high K, low HCO3 (acidosis), high PO43- – abnormalities may be present due to diarrhoea + AKI

• PT, PTT – normal (to rule out other causes of thrombocytopenia e.g. DIC) but reduced values may be seen during active HUS

• Stool culture on sorbitol-MacConkey agar
o To detect Shiga producing E. coli
o Shiga-toxin producing E. coli cannot ferment sorbitol + appear as white colonies
• PCR
o To detect Shiga toxin 1/2

• Proteins involved in complement regulation
o Ordered initially if familial disease is suspected
o Abnormal levels of complement

The clotting screen is normal in HUS

Question 10

Myelofibrosis ix

Answer 10

• FBC - ?anaemia
• Peripheral blood film
o Hallmark of PMF – promyelocytes, myelocytes, metamyelocytes, myeloblasts, nucleated RBC
o Other findings – leuko-erythroblastosis, TEARDROP POIKILOCYTOSIS, large platelets, megakaryocyte fragments
o Thrombocytosis more common than thrombocytopenia

• BM aspiration
o “Dry tap” – buzzword!
o Unable to aspirate marrow because of presence of marrow fibrosis

• BM biopsy
o Marrow fibrosis (increased reticulin deposit)

• XRays – increased bone density, prominence of bony trabeculae
• JAK2 V617F mutation present in 45-68% of patients

Question 11

Diagnosis of PMF as defined by WHO

Answer 11

A1+A2 plus any 2 B
• A1 – bone marrow fibrosis >3 (0-4 scale) - dry tap, increased reticulin deposit
• A2 – pathogenic mutation (e.g. in JAK2 or MPL) or absence of both BCR-ABL1 (CML) + reactive causes of bone marrow fibrosis

• B1 – palpable splenomegaly
• B2 – unexplained anaemia (anaemia is normocytic)
• B3 – leuko-erythroblastosis
• B4 – tear-drop RBC
• B5 – constitutional symptoms
• B6 – histological evidence of extramedullary haematopoiesis

Question 12

DIC ix

Answer 12

• Low Hb (MAHA is a component of DIC)
• Low platelets
• PT + APTT - prolonged

• Fibrinogen - low
o Low due to excessive consumption

• D-dimer/fibrin degradation products/soluble fibrin – high
o Evidence of plasmin-mediated biodegradation of fibrin + fibrinogen

• Peripheral blood film – schistocytes (MAHA)
• Other findings – low natural anticoagulants (antithrombin, protein C)

• Factor V, VIII, X, XIII - low
o Ix to consider
o If specific/multiple coagulation factor deficiencies are suspected, measurement of coagulation factors helps in choosing a specific replacement therapy

Question 13

DIC scoring system + scores

Answer 13

• Platelet count
o >100,000 – 0
o 50,000-100,000/microL – 1
o <50, 000/microL - 2

• Increase in fibrin markers (e.g. d-dimer, fibrin degradation products)
o No increase – 0
o Moderate increase – 2
o Strong increase – 3

• PT prolongation (N: 11-12.5s)
o <3s – 0
o >3 - <6 – 1
o >6 – 2

• Fibrinogen level
o >1 g/L - 0
o <1 g/L -1

> 5 – overt DIC, repeat score daily
<5 – non-overt DIC – repeat next 1-2 days

Question 14

TTP ix

Answer 14

• Plt count – decreased
• Hb - <80
• Haptoglobin – decreased (as a result of haemolysis)
• Blood film – schistocytes (hallmark of the disease)
• Reticulocyte count – raised
• U+Es – raised
• LDH – raised
• Unconjugated bilirubin – raised
• Serological tests – HIV, HBV, HCV, auotantibody screen, pregnancy test
• Urinalysis – proteinuria, microscopic haematuria
• Direct Coombs’ test – to rule out MAHA Ix to consider
• ADAMTS-13 activity assay – decreased activity
• Anti-ADAMTS13 antibodies

Question 15

ITP ix

Answer 15

• FBC + blood film
o Isolated thrombocytopenia (<100 x 10^9 /L) (in the absence of an identifiable cause)
• Clotting screen (normal PT, APTT, fibrinogen)

• No testing for ab or BM examination - Autoantibodies (antiplatelet antibody may be present but not used routinely for diagnosis, anticardiolipin antibody, antinuclear antibody)

Question 16

Hodgkin’s lymphoma ix

Answer 16

• CXR – mediastinal lymphadenopathy

• Excisional lymph node biopsy
Multinucleated giant cells (Reed-Sternberg cell aka Owl’s eyes)
Popcorn cells (lymphocytic + histiocytic cell)

• PET-CT – staging, most common radiotracer is fluorodeoxyglucose (FDG), after chemotherapy to confirm response before commencement of consolidative radiotherapy
• BM biopsy for staging
• Immunohistochemical studies – to differentiate HL from other lymphomas, CD30+
• Ann Arbor staging system

• FBC
o Low Hb + plt 2y to BM involvement
o Exclude leukaemia, mononucleosis, other causes of lymphadenopathy

• ESR - elevated
• Metabolic panel – performed to evaluate baseline liver + renal function prior to commencement of treatment (increase in LDH, decrease in albumin has prognostic significance)
• HIV tests – necessary in patients with suspected Hodgkin’s lymphoma

Question 17

Non-Hodgkin’s lymphoma ix

Answer 17

•	FBC
o	Thrombocytopenia (liver or BM involvement)
o	Pancytopenia (BM involvement))

• Blood smear
o Nucleated RBC
o L shift (BM involvement), L shift – early WBC precursors
o NO Reed Sternberg cells

• Tissue sampling (e.g. skin, lymph node, BM)
o Helpful in establishing dx + staging (should be sent for flow cytometry, immunohistochemistry, cytogenetics)

• CXR
o Mediastinal adenopathy
o Pleural or pericardial effusions
o Parenchymal involvement

• Basic metabolic panel – assesses kidney, electrolyte, glucose function
• LFTs – liver involvement with lymphoma
• LDH – indirect indicator of the proliferative rate of lymphoma
• Serology – HIV, HTLV-1, HCV

• To determine tumour surface markers - establishes type of lymphoma

• Flow cytometry (performed on blood, BM, lymph node suspensions, body fluids)
• Immunohistochemistry (performed on tissues)

• To distinguish malignant lymphoma from benign conditions (hyperplasia, inflammation)

• PCR for tumour markers (when little material is available)
• Immunoglobulin gene rearrangement studies

• Cytogenetics studies +/- fluorescence in situ hybridisation (FISH)
o Identifies chromosomal translocations
o Essential for dx of Burkitt’s lymphoma

• LP
o Any lymphoma with neurological signs
o Lymphomas with high risk of CNS relapse
o Abnormal cells, low glucose, high protein, high pressure

• For staging
o PET scan
o CT scan

• Ann Arbor staging system

Question 18

Malaria ix

Answer 18

• Giemsa-stained thick and thin blood film - gold standard
o Venous blood specimen in an EDTA tube
o Detection of asexual or sexual forms of the parasites inside erythrocytes
o Thick – identifies that parasites are present, thin – identifies species
o Where the blood film is negative, at least 2 further films should be obtained over the subsequent 48h before excluding the diagnosis

• PCR
o Useful in specimens where parasitaemia may be below the detectable level of blood film examination
o Species identification if difficulties on microscopy

• Rapid diagnostic tests (RDTs)
o Immunochromatographic tests
o Detect presence of malaria antigen or enzyme
o Give a visible band after 15 minutes if positive

• FBC
o Anaemia common with all species
o Thrombocytopenia common with Plasmodium falciparum

• Urinalysis
o Severe Plasmodium falciparum infections - massive haemolysis + acute tubular necrosis - acute renal failure with haemoglobinuria + proteinuria

• ABG
o Severe malaria - tissue hypoxia due to - microvascular obstruction, impaired RBC deformability, anaemia, hypovolemia, hypotension - lactic acidosis, impaired level of consciousness
• U+Es – may show low Na+, increased creatinine
• LFTs – often abnormal
• Low glucose

Question 19

How is the diagnosis of myelodysplasia made?

Answer 19

Diagnosis of MDS is typically made by
•	Excluding other non-MDS causes of cytopenias
 •	Presence of some combination of
   Dysplastic cell morphology
   Increased marrow blasts
   Karyotypic abnormality

Question 20

Myelodysplasia ix

Answer 20

•	FBC – one or more cytopenias
o	Anaemia – Hb <100g/L
o	Normocytic or macrocytic RBC 
o	Neutropenia
o	Thrombocytopenia 

• Blood film
o Dimorphic RBC
o Oval macrocytic red cells
o Pappenheimer bodies
o Basophilic stippling
o Dysplasia evidenced as –> erythrocytes with anisocytosis (varying sizes) and poikilocytosis (abnormal shape)
o Granulocytes with ABSENT granulation + HYPOSEGMENTED nuclei

• Reticulocyte count
o Inappropriately normal or low – inadequate reticulocyte response for degree of anaemia

• Serum EPO
o Elevated
o Except in concurrent renal failure where it’s low

• BM aspiration with iron stain
o Amount of dysplasia + proportion of undifferentiated myeloblasts
o Single or multilineage dysplasia
o Bone marrow blasts <20%
o Prussian blue iron staining of BM aspirate – ringed sideroblasts (abnormal erythroid precursor cells which have granules around the nucleus)

• BM core biopsy
o Hypercellular marrow due to ineffective haematopoiesis
o Commonly shows megaloblastoid erythropoiesis

• BM cytogenetic analysis
o Can detect chromosomal abnormalities, characteristic of MDS
o Deletion, monosomy, trisomy usually affecting Chr 5, 7, 8

• HLA typing
o For candidates for haematopoietic stem cell transplantation
o For candidates requiring extensive platelet transfusions

• RBC folate, Serum B12, Iron studies (serum iron, TIBC, ferritin) – to rule out other causes of anaemia
• HIV testing – to rule out other causes of cytopenias

Question 21

Haemophilia ix

Answer 21

• APTT – prolonged (intrinsic pathway affected)
• Plasma factor VIII + IX assay – decreased or absent
• FBC – anaemia if significant bleeding, performed to rule out thrombocytopenia
• PT, bleeding time, fibrinogen levels, von Willebrand factor - normal (extrinsic pathway not affected)
• Mixing study – correction of the APTT with mixing patient plasma w normal plasma suggests coagulation factor deficiency

For complications
CT head – haemorrhage
MRI, Doppler US – arthropathy
Abdominal US + endoscopy – GIB

Question 22

Haemochromatosis ix

Answer 22

•	Haematics
o	TIBC – low
o	Transferrin – low
o	Transferrin saturation – high
o	Serum ferritin - high
o	Serum iron - high

• Serum fasting transferrin saturation
o Phenotypic hallmark of the disorder
o First laboratory test to become abnormal
o >45%

• Serum ferritin
o Most widely used biochemical test for iron overload – high sensitivity
o Acute inflammatory protein – low specificity
o >674 picomols/L (>300 ng/mL) in meno
>449 picmols/L (>200 ng/mL) in women

• HFE genetic testing
o Initial HFE mutation analysis should evaluate C282Y and H63D polymorphisms in all patients with otherwise unexplained increased serum ferritin + increased transferrin saturation
o C282Y mutation homozygosity is the most common genetic abnormality associated with the disease in patients of northern European descent
o Should only be performed in those with increased transferrin saturation

• MRI liver
o Detects + quantifies hepatic iron excess

• Liver biopsy
o The most sensitive + specific test for measuring liver iron content
o No longer necessary to diagnose haemochromatosis, genetic testing is very reliable

•	Hand XR
o	Squared-off bone ends 
o	Hook like osteophytes
o	Joint space narrowing
o	Sclerosiso	Chondrocalcinosis (radiographic calcification in hyaline +/or fibrocartilage)
o	Cyst formation 

• Echocardiogram
o Should be performed in patients with a raised ferritin level
o Haemochromatosis can lead to cardiomyopathy + conduction abnormalities leading to arrhythmias
o Mixed dilated-restrictive or dilated cardiomyopathy

• Testosterone, FSH, LH assays
o Hypogonadism is the second most common endocrine disorder associated with the disease after diabetes

Question 23

How to exclude differentials for hyperferritinaemia

Answer 23

• Inflammation – check CRP
• Chronic alcohol consumption
• Liver cell necrosis – check ALT
• Metabolic syndrome – check BP, BMI, triglycerides, glucose
• Anaemia – check Hb, MCV

Question 24

ALL ix

Answer 24

• FBC with differential
o Normochromic normocytic anaemia with low reticulocyte count
o Leucocytosis, neutropenia, thrombocytopenia

• Blood film
o Leukaemic lymphoblasts

• BM aspiration + trephine biopsy
o Presence of >20% lymphoblasts
o BM hypercellularity
o Wright or Giemsa stain

• Immunophenotyping (on BM or peripheral blood)
o ALL blasts express surface antigens + molecular markers that help to identify their specific lineage (i.e. the fact that they are lymphoid cells)
o In ALL blast cells are +ve for terminal deoxynucleotidyl transferase
Lack staining for myeloperoxidase
Will not have granules in the cytoplasm(compared to AML)

• LP - to detect cerebral involvement
• FISH can detect t(12;21) forming the ETV6-RUNX1 fusion gene on Chr12
• Check liver (infiltration) + kidney (uric acid deposition) function

• Clotting
o DIC may occur – this produces an elevated PT, decreased fibrinogen, presence of FDP

• Serum electrolytes
o Degree of uric acid elevation – reflects extent of tumour burden
o Hypercalcaemia – bony infiltration, ectopic release of PTH
o Hyperphosphatemia – ineffective leukopoiesis, chemotherapy induced tumour lysiso Hyperkalaemia - leukaemic cell lysis
o LDH – raised

Leucocytes smear + stain with Periodic acid achiff stain

Question 25

AML ix

Answer 25

• FBC with differential o Macrocytic anaemia o Leucocytosis, neutropenia, thrombocytopenia • Blood film o Hypergranulated blasts with AUER RODS o Not sufficient to establish dx of AML, BM biopsy required • BM aspiration + trephine biopsy – diagnostic procedure o Presence of >20% blasts o BM hypercellularity o Auer rods o Immunophenotyping + immunochemistry required to confirm the dx • Immunophenotyping (on BM or peripheral blood) o To distinguish between AML+ ALL o Granules in cytoplasm, will express myeloid peroxidase in those granules, may have auer rods • Coagulation panel o PT, APTT, D-dimer (may be mildly prolonged with normal fibrinogen + d-dimer) o If all tests are abnormal (prolonged PT + APTT, raised d-dimer) - suspect DIC • Serum electrolytes o Degree of uric acid elevation – reflects extent of tumour burden o Hypercalcaemia – bony infiltration, ectopic release of PTH o Hyperphosphatemia – ineffective leukopoiesis, chemotherapy induced tumour lysis o Hyperkalaemia - leukaemic cell lysis o LDH raised stains with Sudan black (preferentially stains myeloblasts against lymphoblasts and so is useful in the differentiation of AML and ALL)

Question 26

CLL ix

Answer 26

• FBC with differential o Absolute lymphocytosis (>5000 monoclonal B lymphocytes/mcL in peripheral blood for at least 3 months) o Anaemia (31%) o Thrombocytopenia (16%) • Hypogammaglobulinaemia (predisposes to persistent infections) • Blood film o Lymphocytosis o Smudge cells/smear cells present o Small mature lymphocytes o Narrow border of cytoplasm o Dense nucleus lacking discernible nucleoli + having partially aggregated chromatin o Spherocytes + polychromasia if there is active haemolysis (autoimmune haemolytic anaemia) • BM aspirate o Lymphocytic replacement of normal marrow elements • Flow cytometry of peripheral blood (immunophenotyping) o Most valuable test to confirm CLL o Circulating clonal B lymphocytes express cell surface markers typical of CLL (dim surface Ig, CD5, CD19, CD20, CD23)

Question 27

CML ix

Answer 27

• FBC with differential o Elevated WBC o Normochromic normocytic anaemia o Differential – granulocytes at all stages of development, increased number of eosinophils + basophils ``` • Blood film o WBC are mature/maturing myeloid cells o Elevated basophils and eosinophils o Myeloblasts o Granulocytosis ``` • BM biopsy o Granulocytic hyperplasia o Hypercellular BM • Cytogenetics o Philadelphia chromosome t(9,22) • Quantitative reverse transcription PCR (qRT-PCR) incl breakpoint analysis o Detection of BCR-ABL fusion ``` • FISH (fluorescent in situ hybridisation) o t(9,22) positive ``` • Complete metabolic profile o K, LDH, uric acid – may be elevated due to extensive cell turnover

Question 28

Multiple myeloma ix

Answer 28

• Serum/urine electrophoresis + Bence Jones protein urine assessment o Diagnostic test for MM o Serum protein electrophoresis - MONOCLONAL IgG (or IgA) band o Urine - positive for Bence Jones protein (immunoglobulin light chain) o Paraprotein spike (IgG > 35 g/l or IgA >20 g/L + light chain urinary excretion >1g/day) o Hypogammaglobulinaemia • BM aspirate + trephine biopsy o Diagnostic test for MM o Monoclonal plasma cell infiltration in the bone marrow >10% ``` • Peripheral blood film o Rouleaux (aggregations of RBC) ``` • Serum free light-chain assay o Increased concentrations of free light chain in serum • Immunofixation of serum + urine o To confirm the presence of a paraprotein ``` • MRI o Gold standard to determine the extent of myeloma bone disease (also used to investigate possible spinal cord compression) o Osteopenia o Osteolytic lesions o Pathological fractures ``` • FBC o Normocytic + normochromic anaemia o Reduced blood cell counts resulting from bone marrow infiltration ``` • Serum calcium, plasma viscosity, ESR, CRP, Urea + Cr, ALP o Hypercalcaemia o Hyper viscosity o Elevated ESR o Elevated CRP o Elevated Urea + Cr o NORMAL ALP ``` • Serum urea, creatinine, electrolytes, albumin, ALP o Increased tumour cell turnover - raised uric acid o Cr >176 mmol/L in renal impairment o Total protein concentration usually raised in MM o ALP is NORMAL (osteoblasts produce ALP whereas in MM only osteoclasts are activates) • XR of symptomatic areas for people with bone pain o To rule out pathological fractures o Skull - multiple “punched out” lucencies within the skull vault

Question 29

Criteria for the diagnosis of MM (all 3 needed)

Answer 29

* Monoclonal plasma cells in marrow >10% * Monoclonal protein in serum or urine • Evidence of myeloma-related organ or tissue impairment o Hypercalcaemia (>2.6 mmol/L) o Renal insufficiency (serum Cr >176.8 μmol/L) o Anaemia (Hb <100g/L or 20g below normal range) o Lytic bone lesions, osteoporosis, pathological fractures (osteolytic lesions, pepperpot skull, pathological fractures)) [CRAB – calcium, renal impairment, Anaemia (+ neutropenia, thrombocytopenia), Bone pain/lesions]

Question 30

Sickle cell disease ix

Answer 30

Diagnosis made during a sickle cell crisis if there is no newborn screening To confirm dx • Hb Electrophoresis o Most commonly used test to determine the presence of HbS FBC • Normocytic anaemia • Normal MCV (80-100) • Increased reticulocyte production index >2% Due to intravascular + extravascular haemolysis • Increased LDH • Decreased haptoglobin + decreased free plasma Hb • Increased Unconjugated bilirubin • Blood film o High reticulocyte count (do not have a nucleus, but you can see the rRNA staining) o Nucleated RBC o Anisocytosis o Sickle cells o Howell Jolly bodies (hyposplenism) o Target cells (hyposlenism) o Reticulocytes increased in haemolytic crises + decreased in aplastic crises o In patients wit very low reticulocyte counts (<1%), parvovirus infection should be strongly considered • DNA based assays/ high performance liquid chromatography o Confirm diagnosis + further identify the genotype o Allow distinction between heterozygotes + homozygotes Other tests • Sickle solubility test – a mixture of HbS in a reducing solution (e.g. sodium dithionite) gives a turbid appearance (precipitation of HbS), whereas normal Hb gives a clear solution • Sickling of red cells on blood film with 2% sodium metabisulphite

Question 31

Thalassaemia ix - generally

Answer 31

``` Blood • FBC o Decreased Hb o Low MCV, Low MCH o Increased RBC o Increased reticulocytes o Increased WBC - from bone hyperplasia o Platelet count may be decreased in splenomegaly or increased in bone hyperplasia ``` ``` • Blood film o Microcytic, hypochromic anaemia o Reticulocytes o Target cells o Polychromasia o Red cell fragments o Tear drops ``` • Bone marrow o Hypercellular with erythroid hyperplasia * Increased serum Fe * Increased ferritin • Electrophoresis o HbA2 >3.5% * If microcytosis is found - tests for iron deficiency + anaemia of chronic disease, testing for thalassaemia considered in patient of appropriate family originImaging * Skull XR – “hair-on-end” appearance, facial deformity and non-pneumatisation of the maxillary sinuses * CXR may show an enlarged heart + cardiac failure * CT/MRI – used to evaluate amount of iron in the liver in patients on chelation therapy Other tests • ECG + echo – monitor cardiac function • Liver biopsy to assess iron deposition + degree of haemochromatosis

Question 32

Thalassaemia ix specifically for HbH or Hb Bart

Answer 32

All the general ix and • Electrophoresis – only for diagnosing HbH + Hb BartHbH • Brilliant cresyl blue staining of RBC o HbH inclusions in peripheral RBC - Heinz bodies represent β-chain tetramers • HbH is unstable + precipitates in the erythrocyte, giving it the appearance of a golf ball

Question 33

Thalassaemia B ix

Answer 33

All the general ix and • Haemoglobin analysis o Beta thalassaemia trait – mostly HbA, increased HbF, increased HbA2 o Beta thalassaemia major - decreased HbA, increased HbF, increased HbA2 • LFTs o Performed in patients with beta-thalassaemia intermedia + major o Increased unconjugated bilirubin - jaundice, gallstones o Increased LDH

Question 34

VWD ix

Answer 34

Type 1+3 or type 2 depends on if there is or if there’s not of FVIII deficiency • Factor VIII measurement o FVIII binds to VWF which in turn prevents breakdown of factor VIII - deficiency of VWF can also lead to factor VIII deficiency (Type 1 + Type 3) o In type 2, VWF-FVIII levels are normal - studies of platelet aggregation with sub-endothelium are necessary • PT – measures extrinsic pathway, normal (12-15s) * APTT – measures intrinsic pathway, prolonged if FVIII activity is decreased (>34s) * Normal platelet count + morphology * Decreased platelet aggregation, presence of ristocetin * Abnormal PFA-100 test (because of decreased platelet aggregation) • Plasma levels of VWF o Quantitative deficiency – detected by VWF antigen assay (diagnostic for VWD if <30%) o Qualitative deficiency – glycoprotein binding assay, ristocetin cofactor, risocetin-induced platelet agglutination • Type 2 VWD o Ratio of VWF: VWF antigen <0.6 • Collagen-binding function reduced ↑ APTT, ↑ bleeding time, ↓ vWF levels, N plts, normal PT, (↓ factor 8 if VWD T1 or T3)

Question 35

PV ix polycythaemia vera PCV

Answer 35

• Increased Hb o >165 g/L in men o >160 g/L in women o In the setting of hypoxia repeat test several weeks after the hypoxia has been corrected • Increased HCT o >52% in men o >48% in women • Increased RBC mass o Gold standard in ruling out PV when Hb/Hct is equivocal or affected by certain clinical conditions e.g. volume overload o Therefore in secondary polycythaemia RBC are raised • Decreased ferritin o In polycythaemia vera, ferritin is often low because of increased demand for iron o In secondary polycythaemia it is usually normal • BM biopsy – can also be normal o Hypercellularity with trilineage growth (panmyelosis) o Prominent erythroid, granulocytotic, megakaryocytic proliferation o Pleomorphic, mature megakaryocytes o Tear drop cells o Leucocytosis o Thrombocytosis o Can also look for signs of fibrosis in the spent stage • JAK2 V617F gene mutation usually present * Increased WBC * Incrased Plt * Decreased MCV * Decreased EPO • Increased serum uric acid o Due to rapid cell turnover from expanded haematopoiesis o Elevated levels predispose to gout + urate kidney stones

Question 36

Criteria for PV dx

Answer 36

Need 2 major + 1 minor criteria Or 1st major criterion + 2 minor criteria Major criteria • Hb >185 g/L (M), >165 g/L (F) (or elevated RBC mass >25% above mean normal predicted value) • Presence of JAK2 V617F mutation (or other functionally similar mutations such as the exon 12 mutation of JAK2) Minor criteria • BM biopsy o Hypercellularity o Prominent erythroid, granulocytic, megakaryocytic proliferation • Serum EPO level below normal range • Endogenous erythroid colony formation in vitro

Question 37

Antiphospholipid syndrome ix

Answer 37

• Anti-phospholipid antibodies must be positive on 2 occasions, 12 weeks apart: o Anticardiolipin antibodies o Anti-b2-glycoprotein I antibody o Lupus anticoagulant • FBC o Thrombocytopenia may be present often due to an immune mechanism or the presence of another autoimmune disease (ITP) o APTT prolonged due to antibodies against phospholipids

Question 38

Diagnosis of antiphospholipid syndrome

Answer 38

For the diagnosis you need at least one of the clinical criteria + at least one of the laboratory criteria to be present Clinical criteria • Hx of vascular thrombosis - >1 episodes of arterial, venous, small vessel thrombosis • Pregnancy complications Laboratory criteria • Anti-cardiolipin antibody • Anti-b2-glycoprotein I antibody • Lupus anticoagulant

Question 39

How would you differentiate ITP from TTP on a blood film?

Answer 39

ITP Normal morphology of RBC, WBC, thrombocytopenia TTP fragmented RBC (schistocytes) thrombocytopenia

Question 40

Blood film - hyposplenism

Answer 40

Howell Jolly bodies Target cells Pappenheimer bodies Siderotic granules

Question 41

Blood film - iron deficiency anaemia

Answer 41

Target cells pencil poikilocytes if combined with B12/folate deficiency a "dimorphic" film occurs with mixed microcytic + macrocytic cells

Question 42

Blood film - myelofibrosis

Answer 42

Tear drop poikilocytes

Question 43

Blood film - intravascular haemolysis

Answer 43

Schistocytes

Question 44

Blood film - megaloblastic anaemia

Answer 44

Hypersegmented neutrophils

Question 45

Most appropriate ix to determine iron stores in the body

Answer 45

Serum ferritin (because it originates from the storage pools in the BM, spleen and liver) only accurate if CRP is normal

Question 46

Aplastic anaemia ix

Answer 46

``` LOW o RBC o WCC o plt o reticulocytes ``` RAISED • EPO • MCV • bleeding time (low platelets) o For dx, at least 2 of the following peripheral cytopenias must be present  Hb <100g/L  Plt <50 x 10^9/L  Absolute neutrophil count <1.5 x 10^9/L PANCYTOPENIA • BM biopsy – hypocellular bone marrow with no abnormal cells o Required for definitive dx o decreased counts of haematopoietic stem cells with normal cellular morphology o HYPOCELLULAR marrow – dry tap o Absence of any infiltrative disorder (e.g. malignancy, fibrosis, dysplasia, blasts) – no abnormal cells o MACROCYTIC anaemia

Question 47

Pernicious anaemia ix

Answer 47

90% demonstrate anti-parietal ab | 60% have anti-IF ab (more specific) intrinsic factor

Question 48

Ann arbor system for the staging of lymphoma

Answer 48

I – one node region involved II – 2+ ipsilateral regions III – bilateral node involvement IV – extranodal disease A – B symptoms abent B – symptoms present (worse prognosis)