haematology Flashcards
what cells are specific to sickle cell?
Howell-Jolly cells are characteristic of sickle cell disease
blood film- sickle cell
classical ‘target’ appearance
what test is most specific for diagnosing sickle cell?
haemoglobin electrophoresis
in sickle cell what medication is started to reduce incidence of complications and crises?
Hydroxycarbamide reduces the frequency of painful episodes and the risk of life-threatening illness or death. However, it can also increase your risk of infections. It is advised not to be taken in pregnancy.
Hydroxycarbamide essentially makes your red blood cells bigger, stay rounder and more flexible. Therefore, less likely to turn into a sickle shape. This is achieved by increasing a special kind of haemoglobin called haemoglobin F.
investigations in autoimmune haemolytic anaemia
Investigations
general features of haemolytic anaemia
anaemia
reticulocytosis
low haptoglobin
raised lactate dehydrogenase (LDH) and indirect bilirubin
blood film: spherocytes and reticulocytes
specific features of autoimmune haemolytic anaemia
positive direct antiglobulin test (Coombs’ test).
management of autoimmune haemolytic anaemia
steroids (+/- rituximab) are generally used first-line
how often should adults with sickle cell receive the pneumococcal polysaccharide vaccine?
Sickle cell patients should receive the pneumococcal polysaccharide vaccine every 5 years
what drugs can cause aplastic anaemia?
cytotoxics, chloramphenicol, sulphonamides, phenytoin, gold
toxins: benzene
what is aplastic anaemia characterised by?
pancytopenia and a hypoplastic bone marrow
what type of anaemia does sickle cell cause?
Sickle cell disease causes a normocytic anaemia with raised reticulocyte count – due to haemolysis
presentation of ALL
anaemia, neutropaenia and thrombocytopaenia
serious complication of polycythaemia rubra vera
Polycythaemia rubra vera - around 5-15% progress to myelofibrosis or AML
most common type of Hodgkins lymphoma
Hodgkin’s lymphoma - most common type = nodular sclerosing
multiple myeloma presentation
Calcium
Hypercalcaemia occurs as a result of increased osteoclast activity within the bones
This leads to constipation, nausea, anorexia and confusion
Renal
Monoclonal production of immunoglobulins results in light chain deposition within the renal tubules
This causes renal damage which presents as dehydration and increasing thirst
Other causes of renal impairment in myeloma include amyloidosis, nephrocalcinosis, nephrolithiasis
Anaemia
Bone marrow crowding suppresses erythropoiesis leading to anaemia
This causes fatigue and pallor
Bleeding
bone marrow crowding also results in thrombocytopenia which puts patients at increased risk of bleeding and bruising
Bones
Bone marrow infiltration by plasma cells and cytokine-mediated osteoclast overactivity creates lytic bone lesions
This may present as pain (especially in the back) and increases the risk of fragility fractures
Infection
a reduction in the production of normal immunoglobulins results in increased susceptibility to infection
myeloma- investigations
Bloods will show anaemia (FBC) and thrombocytopenia (FBC); raised urea and creatinine (U&E) and raised calcium
Peripheral blood film: rouleaux formation
Serum or urine protein electrophoresis: raised concentrations of monoclonal IgA/IgG proteins will be present in the serum. In the urine, they are known as Bence Jones proteins
Bone marrow aspiration and trephine biopsy: confirms the diagnosis if the number of plasma cells is significantly raised
Whole-body MRI (or CT if MRI is not suitable) is used to survey the skeleton for bone lesions
A common X-ray finding is a ‘rain-drop’ skull. This is numerous randomly placed dark spots seen on X-ray which occur due to bone lysis.
