Myeloproliferative disorders Flashcards
Definition of myeloproliferative disorders
Group of conditions characterized by clonal profliferation of one or more haemopoietic components
Raised red cell mass, Hb, red cell count and packed cell volume
Polycythaemia
Causes of polycythaemia
Primary: Polycythaemia vera
Familial polycythaemia
Secondary: Increased EPO
Disease states (renal Ca), high altitude, chronic hypoxia
Red cell mass normal, plasma volume reduced
Relative (Pseudo) Polycythaemia
Causes of Relative polycythaemia
Dehydration, burns, vomiting, diarrhoea, cigarette smoking
An MPD where erythroid precursors dominate the BM
Incidence rises with age
JAK2 point mutation
Polycythaemia rubra vera
Clinical feature of PRV
Hyperviscosity, hypervolaemia, hypermetabolism
Blurred vision, headache
Plethoric (red nose), gout thrombosis and stroke, retinal vein engorgement, erythromelagia
Splenomegaly
Histamine release > aquagenic pruritus and peptic ulcers
Investigations for PRV
Raised Hb, HCT, possibily plateletsWCC
Low serum EPO
Treatment for PRV
Venesection
Hydroxycarbamide, aspirin
Myeloproliferation leads to fibrosis of the BM or replacement with collagenous tissue
Myelofibrosis
Clincal features of myelofibrosis
Elderly Pancytopaenia Extramedullary-related symptoms Extramedullary haematopoeisis - hepatosplenomegaly, WL, fever Budd-Chiari
Investigations of myelofibrosis
Tear drop poikilocytes, leukoerythroblasts
BM - fibrosis, dry tap
Treatment of myelofibrosis
Support with blood products
Sometimes splenectomy
Hydroxycarbamide, thalidomide, steroids and SCT
MPD where megakaryocytes dominate the BM
50% associated with JAK2
Essential Thrombocythaemia
Clinical features of essential thrombocythaemia
Incidental finding
Venous and arterial thrombosis, gangrene, haemorrhage
Erythromelalgia
Splenomegaly, dizziness, headaches, visual disturbances
