Haem - ix Flashcards
Iron deficiency anaemia on blood film
Anisopoikilocytosis
Pencil cells
Hypochromic + microcytic
Iron studies in anaemia of chronic disease
Decreased/Normal transferrin Decreased TIBC Normal transferrin saturation Increased ferritin Increased herpcidin Normocytic or mcrocytic anaemia
Iron studies in iron deficiency anaemia
Increased transferrin
Increased TIBC
Decreased transferrin saturation
Decreased ferritin
Hb electrophoresis to ix 2 diseases
Sickle cell disease
Thalassaemia
Sickle cell anaemia ix
Hb electrophoresis
Blood film
Howell- Jolly bodies (usually removed by spleen, therefore also a marker of hyposplenism (elderly patient))
Sickle cells
G-6-PD deficiency on blood film
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
Mutation classically assosciated with polycythaemia vera and myelofibrosis
JAK2 V617F
E coli strain causing HUS
EHEC O157H7
HUS ix
haemolytic uraemic syndrome
- 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
Myelofibrosis ix
• 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
Diagnosis of PMF as defined by WHO
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
DIC ix
- 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
DIC scoring system + scores
• 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
TTP ix
- 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
ITP ix
• 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)
Hodgkin’s lymphoma ix
• 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
Non-Hodgkin’s lymphoma ix
• 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
Malaria ix
• 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
How is the diagnosis of myelodysplasia made?
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
Myelodysplasia ix
• 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
Haemophilia ix
- 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
Haemochromatosis ix
• 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
How to exclude differentials for hyperferritinaemia
- Inflammation – check CRP
- Chronic alcohol consumption
- Liver cell necrosis – check ALT
- Metabolic syndrome – check BP, BMI, triglycerides, glucose
- Anaemia – check Hb, MCV
ALL ix
• 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
