Role of Morphology in the Era of Advanced Cellular Analysis. Barbara J Bain

Transcription

1 Role of Morphology in the Era of Advanced Cellular Analysis Barbara J Bain

2 Role of Morphology Speedy diagnosis Providing a context for interpreting sophisticated modern tests Indicating a likely diagnosis that directs which tests are performed Detecting erroneous automated counts or explaining the significance of an automated instrument output

3 Speedy diagnosis

4 When does speedy diagnosis matter? Acute promyelocytic leukaemia Any acute leukaemia with leucostasis Burkitt lymphoma Haemophagocytic lymphohistiocytosis Thrombotic thrombocytopenic purpura Certain infections

5 Acute promyelocytic leukaemia Easy Not so easy Even more difficult

6 Acute promyelocytic leukaemia If you suspect acute promyelocytic leukaemia, use your automated instrument output to confirm (if MPO- or SBB-based) Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

7 Acute promyelocytic leukaemia Thinks of this diagnosis when there is thrombocytopenia and only mild anaemia and search the film carefully However sometimes circulating leukaemic cells are absent

8 Leucostasis Leucostasis is prognostically adverse so rapid notification of the diagnosis and the WBC to the clinician is important In a series of 29 AML patients (acute promyelocytic leukaemia excluded) presenting with headaches, dizziness and visual symptoms the median WBC was /l (range ) Lieberman et al. (2017) Acta Haematologica, 138, 116.

9 Leucostasis A third of patients had intracranial haemorrhage (ICH) Subdural in 5 patients Intraparenchymal in 3 patients Subarachnoid in 1 patient In the patients with ICH the median survival was 10 months Lieberman et al. (2017) Acta Haematologica, 138, 116.

10 Leucostasis Leucostasis is associated with a poor prognosis not only because of ICH but also because of an association with Hypoxia Tumour lysis syndrome Coagulopathy Lieberman et al. (2017) Acta Haematologica, 138, 116.

11 Leucostasis Leucostasis occurs mainly in acute leukaemia It is more likely in acute monocytic/ monoblastic leukaemia because of the greater size of the cells This is a coronary artery at autopsy in a patient who died with leucostasis due to acute myelomonocytic leukaemia with a WBC of /l Thornton and Levis (2007) New Engl J Med, 357, 1639.

12 Leucostasis Hyperleucocytosis in T-ALL

13 Burkitt lymphoma Peripheral blood (PB) involvement is more likely in AIDSassociated Burkitt lymphoma

14 Haemophagocytic lymphohistiocytosis Usually this is not a diagnosis that can be suspected from the PB Usually there is just pancytopenia However here we have activated monocytes in a case following transplantation Davies, Hart, de la Fuente and Bain (2018) Am J Hematol, in press.

15 Thrombotic thrombocytopenic An emergency because of the need for urgent plasma exchange This is a classic case purpura From Vallespi T and Garcia-Alonso L, Atlas of Blood cells and Blood Disease.

16 Thrombotic thrombocytopenic purpura Sometimes it is not so easy A 26-year-old Indian woman living in the United Arab Emirates Homozygous for haemoglobin E Hb 88 g/l (normally c. 96) with reticulocyte count 3.8% and platelet count < /l

17 Thrombotic thrombocytopenic purpura She was given three platelet concentrates The next morning she was confused and then lost consciousness ADAMTS13 <5% There were only rare schistocytes Hazarika B and Bain BJ (2012) Thrombotic thrombocytopenic purpura in a patient with hemoglobin E disease-the importance of timely examination of a blood film. Am J Hematol, 87, 996.

18 Other MAHA Ca pancreas Splenectomy Gemcitabine MAHA Acute kidney injury Many pathological processes revealed in the blood film Erblich et al. (2015) The complex morphology of acute kidney injury with microangiopathic hemolytic anemia and hyposplenism. Am J Hematol, 90, 674.

19 Certain infections 29-year-old woman in Accident and Emergency Department Hb 152 g/l, white cell count /l and platelet count /l A citrate sample for coagulation tests was unclottable What is it?

20 Certain infections Meningococcal septicaemia Uprichard and Bain (2008). Am J Hematol, 83, 672.

21 Certain infections An 81-year-old Czech woman, previous lymphoma, previously splenectomised, who had been bitten by her dog three days earlier She died of septic shock 21 hours after admission What is it?

22 Certain infections Capnocytophaga canimorsis Zazula et al. (2015) Clin Microbiol, DOI: /

23 Certain infections Patient with an indwelling venous line Candida glabrata Note: fungi may falsely elevate the platelet count

24 Certain infections A febrile North African child The laboratory were asked to look for malaria parasites What is the diagnosis? Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

25 Certain infections A febrile North African child The laboratory were asked to look for malaria parasites What is the diagnosis? Borreliosis

26 Acutely ill patient 32-year old Italian woman presenting to emergency room Lymphocytosis led to a blood film being examined What do you suspect?

27 Acutely ill patient 32-year old Italian woman presenting to emergency room Lymphocytosis led to a blood film being examined What do you suspect? Cocaine poisoning Fumi M, Pancione Y, Sale S, Rocco V and Bain BJ (2017) Botryoid nuclei resulting from cocaine abuse. Am J Hematol, 92,

28 Providing a context for interpreting sophisticated modern tests

29 Providing a context acute myeloid leukaemia A blast (plus promonocyte) count remains essential CD34-positive cells are not necessarily equivalent to blast cells (monoblasts and promonocytes can be CD34-negative; myeloblasts in NPM1-mutated AML can be CD34-negative)

30 Providing a context acute myeloid leukaemia Morphology can provide the basis for a diagnosis of acute myeloid leukaemia with myelodysplasia-related changes Morphology is essential for the diagnosis of the prognostically poor pure erythroid leukaemia Morphology can provide a clue to a diagnosis of blastic plasmacytoid dendritic cell neoplasm

31 Providing a context acute myeloid leukaemia Morphology can provide the basis for a diagnosis of acute myeloid leukaemia with myelodysplasia-related changes Morphology is essential for the diagnosis of the prognostically poor pure erythroid leukaemia Morphology can provide a clue to a diagnosis of blastic plasmacytoid dendritic cell neoplasm

32 Indicating a likely diagnosis that directs further tests from the everyday to the exotic

33 What do you expect the blood film to show? A 77-year-old woman has fatigue and a burning sensation in her tongue after eating 6 years earlier she had had a total gastrectomy as part of treatment for carcinoma of the pancreas Lee and Jo (2009) A smooth shiny tongue, New Eng J Med, 360, e8.

34 What do you expect the blood This is what it showed Serum B 12 was 55 pg/ml (NR ) film to show? Lee and Jo (2009) A smooth shiny tongue, NEJM, 360, e8.

35 Megaloblastic anaemia Don t be confused by schistocytes Watch out for cases with a normal MCV (RDW is high) Bain BJ (2010) Schistocytes in megaloblastic anemia. Am J Hematol, 85, 599.

36 Megaloblastic anaemia Be aware that vitamin B 12 assays are sometimes erroneous the blood film can be crucial Look out for oval macrocytes, teardrop cells and hypersegmented neutrophils

37 Microcytosis and a low MCH what might it be? Iron deficiency very straightforward Iron deficiency emerging during treatment of folic acid deficiency Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

38 Microcytosis and a low MCH This is more tricky what might it be? The blood film tells you why the patient has developed iron deficiency anaemia Why has this happened? Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

39 Microcytosis and a low MCH what might it be? There is mechanical haemolytic anaemia from a prosthetic heart vale Intravascular haemolysis has led to iron deficiency Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

40 Microcytosis and a low MCH what might it be? Beta thalassaemia trait the range of abnormality Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

41 Microcytosis and a low MCH Rare but important causes what might it be? Congenital sideroblastic anaemia Acquired HbH disease Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

42 Microcytosis failure to interpret the instrument output and examine the blood film can lead to misdiagnosis

43 Microcytosis and a low MCH what might it be? A patient was mistakenly treated for iron deficiency anaemia What do the blood film and histograms tell us?

44 Microcytosis and a low MCH what might it be? Patient Normal control

45 Microcytosis and a low MCH what might it be? Patient Normal control Platelet count is likely to be wrong Low MCV is not due to microcytosis Bain BJ, Varu V, Rowley M and Foale R (2015) Mechanical hemolysis: a low mean cell volume does not always represent microcytosis. Am J Hematol, 90, 1179.

46 Some clues to rare but important conditions What is this? Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

47 Some clues to rare but important conditions What is this? Lead poisoning However the clinician had already made the diagnosis Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell

48 Some clues to rare but important conditions However this diagnosis really mattered The child had microcytosis due to β thalassaemia heterozygosity But what else is going on?

49 Some clues to rare but important conditions Sitosterolaemia was suspected Confirmed by analysis of serum lipids including plant sterols Treated with ezetimibe Due to bi-allelic mutation of ABCG5 or ABCG8 Bain and Chakravorty (2016) Phytosterolemia. Am J Hematol, 91, 643.

50 Some clues to rare but important conditions 21-year-old Kuwaiti woman with severe anaemia Anaemia, jaundiced and transfused at birth Premature gallstones, increased bilirubin and LDH What do you suspect? Al-Jafar et al. Am J Hematol, 88,1089.

51 Some clues to rare but important conditions Pyrimidine 5ʹnucleotidase deficiency Confirmed by assay at St Thomas s hospital Red cell P5ʹN was 1.0 nmol/h/mg Hb (NR 9 20) Al-Jafar et al. Am J Hematol, 88,1089.

52 The platelet count is low what might it be?

53 Detecting erroneous automated counts or explaining the significance of an automated instrument output

54 Detecting erroneous automated counts A count is too low A count is too high Hb is too high A cell has been falsely identified

55 Detecting erroneous automated counts the platelet count is falsely low

56 Detecting erroneous automated counts true platelet count is lower than the automated count Microcytic red cells and red cell fragments White cell fragments Cryoglobulinaemia Hyperlipidaemia Bacteria Fungi Malaria parasites

57 Explanation of abnormal platelet indices, histograms and scatter plots A 37-year-old male who had recently been treated for malaria while in Kenya presented with fever, malaise, headaches and haematuria FBC showed WBC /l, Hb 73 g/l and platelet count /l However platelet histograms were abnormal

58 Explanation of abnormal platelet indices, histograms and scatter plots

59 Explanation of abnormal platelet indices, histograms and scatter plots There was severe thrombocytopenia (optical platelet count /l) ADAMTS13 was undetectable The patient died after suffering a cardiac arrest during plasma exchange Innes AJ and Matthey F (2017) Red cell fragmentation can mask severe thrombocytopenia. Blood, 130, 1484.

60 Erroneous automated counts 49-year-old African male being treated for adenocarcinoma of the colon Weakness, fever, chills Platelet count /l (Sysmex XN 1000, fluorescence channel) Pai and Bhat (2017) BJH, 179, 528

61 Erroneous automated counts Impedance channel, /l What is the explanation? Pai and Bhat (2017) BJH, 179, 528

62 Erroneous automated counts Malaria Schizonts and gametocytes of P. falciparum Fluorescent dye binds to RNA Pai and Bhat (2017) BJH, 179, 528

63 Thrombocytosis and falsely normal or overestimated platelet counts Is the count true? Red cell fragments White cell fragments Fungi Cryoglobulin Are there clues as to aetiology? Basophilia Polycythaemia Leucoerythroblastic

64 Pseudothrombocytosis or falsely normal or overestimated Red cell fragments due to snakebite platelet count Bain BJ (2014) Interactive Haematology Imagebank, 2 nd Edn, Wiley-Blackwell, Oxford

65 Pseudothrombocytosis A routine antenatal blood count sent to the laboratory by a midwife doing a domiciliary visit gave a highly abnormal blood count WBC /l Hb 107 g/l MCV 82.6 fl RDW 20.6 Platelet count /l

66 Pseudothrombocytosis Blood film

67 Pseudothrombocytosis H2 scatterplots

68 Pseudothrombocytosis or falsely normal or overestimated White cell fragments Leukaemia Lymphoma Pseudoplatelets in Burkitt lymphoma platelet counts

69 Conclusion morphology to the rescue