Chronic Myeloproliferative Disorders Flashcards
What are myeloproliferative disorders?
Clonal haemopoeietic stem cell disorders with an increased production of one or more types of haemopoietic cells
How do MPD compare to acute leukaemia on microscopy?
AL - lots of cells, all primitive blasts - no variation/maturation
MPD - more cellular, evidence o fmaturation even tho increased number
What are the 2 subtypes of myeloproliferative disorders?
BCR-ABL1 positive (chronic myeloid leukaemia)
BCR-ABL negative (PRV, essential thrombocythaemia, idiopathic myelofibrosis)
What presentation would make you consider a MPD?
High granulocyte count High red cell count High platelet count Eosinophillia/Basophillia Splenomegaly Thrombosis in an unusual place
What is chronic myeloid leukaemia?
Proliferation of myeloid cells
consists of chronic phase,accelerated phase and blast crisis
Clinical features of CML?
Asymptomaticoften
Splenomegaly
Hypermetabolic symptoms
Gout
What are the lab features of CML?
Normal or decreased Hb
Leucocytosis with neutrophilia and myeloid precursors
What is the philadelphia chromosome?
Hallmark of CML
Reciprocal translocation between chromosome 9 and 22 - results in new gene BCR-ABL1
What drugs can be used in the management of CML?
Tyrosine kinase inhibitors (e.g. Imatinib)
What is PRV?
High Hb/haematocrit accompanied by erythrocytosis (a true increase in red cell mass) but can have excessive production of other lineages
Causes of pseudopolycythaemia
Dehydration
Diuretics
Pregnancy
Obesity
What can polycythaemia by secondary to?
Chronic hypoxia
Smoking
Epo-secreting tumour
Epo therapy
Clinical features of PRV
Splenomegaly Weight loss Gout Marrow failure Thrombosis Headache Fatigue Aquagenic pruritis
What mutation is common in PVR?
JAK2
What does a JAK2 mutation do?
Loss of autoinhibition of Epo - constant erythropoesis
Treatment of PRV
Venesect to reduce haematocrit <0.45
Aspirin
Cytotoxic oral chemo (e.g. Hydroxycarbamide)
What is essential thrombocythaemia?
Uncontrolled production of abnormal platelets
How is ET diagnosed?
Exclude reactive thrombocytosis
Exclude CML
JAK2 mutation (50%)
Characteristic bone marrow appearances
How is ET treated?
Aspirin
Cytoreductive therapy to control proliferation
Clinical features of myelofibrosis
Marrow failure
Splenomegaly
Hypercatabolism
What can be seen on blood film in MF?
Tear-drop shaped RBC and leucoerythroblastic film
What are the causes of a leucoerythroblastic film?
Reactive (sepsis)
Marrow infiltration
Myelofibrosis
Treatment of myelofibrosis
Supportive care (transfusion)
Stemcell transplant
Splenectomy
Jak2 inhibitors?
