Haematology: General

Question 1

name the condition:
excess proliferation of RBCs, WBCs and platelets.
mutation in JAK2 present in >95%
hyperviscosity symptoms(itching after hot bath, headaches, dizziness, tinnitus, erythromyalgia(burning sensation in fingers/toes)
facial plethora and splenomegaly
marrow shows hypercellularity with erythroid hyperplasia
low serum erythropoietin
treated with venesection (if low risk) or hydroxycarbamide(if high risk along with aspirin 75mg OD
transition to myelofibrosis occurs in 30%, or acute leukaemia in 5%

Answer 1

polycythaemia vera

Question 2

persistently raised platelets(>1000x10 to the power of 9/L)
can cause bleeding, or arterial/venous thrombosis
clonal proliferation of megakaryocytes
microvascular occlusion symptoms can occur(headaches, atypical chest pain, light headedness and erythromelalgia)

Answer 2

essential thrombocythaemia

Question 3

megakaryocyte hyperplasia leads to increased production of platelet derived growth factor (PDGF)–>marrow fibrosis and haematopoeisis. This causes massive hepatosplenomegaly.
Presents with: hypermetabolic symptoms (night sweats, fever, weight loss and abdominal discomfort due to splenomegaly, and bone marrow failure (low Hb, infections, bleeding).
On film there is leukoerythroblastic cells (nucleated red cells); and characteristic teardrop RBCs
treatment is with marrow support; allogenic stem cell tranplant may also be curative in young people but has a high risk of mortality.
median survival is 4-5 years.
due to proliferating fibroblasts

Answer 3

myelofibrosis.

Question 4

list some causes of increased thrombocytosis (remembering it may be a reactive phenomenon, if only >450x10 to the power of 9/L; seen with many conditions).

Answer 4

bleeding
infection
chronic inflammation
malignancy
trauma
post-surgery
iron deficiency

Question 5

1) monclonal protein band in serum/urine electrophoresis
2) increased number of plasma cells on marrow biopsy
3) evidence of end-organ damage (hypercalcaemia, renal insufficiency, anaemia)
4) bone lesions

Answer 5

myeloma (diagnostic criteria).
Myeloma is also known as a plasma cell dyscrasia(PCD). Myeloma occurs due to the abnormal proliferation of a single clone of plasma/lymphoplasmacytic cells leading to secretion of immunoglobulin or an Ig fragment, causing the dysfunction of many organs(esp. kidney).
In 2/3rds, there are Bence Jones proteins in the urine(free Ig light chains that are filtered by the kidney)

Question 6

what are these complications of?
hypercalcaemia
spinal cord compression
hyperviscosity (treated with plasmapharesis to remove light chains)
acute renal injury

Answer 6

complications of myeloma