Haem Flashcards
what is multiple myeloma?
neoplastic proliferation of bone marrow plasma cells. Excess immunoglobulins (paraprotein) produced, leading to organ dysfunction
When are Rouleaux formations seen? What are they?
Multiple myeloma. Aggregation of RBC
What is the presentation of multiple myeloma?
OLD CRAB
- old age
- calcium increase (bones, stones, groan, psychic moans)
- renal impairment (light chain deposition –> bence jones proteins in urine)
- anaemia (normocytic normochromic anaemia)
- bone lytic lesions (due to immunoglobulins activitating osteoclasts)
Dx of multiple myeloma?
- FBC: anaemia
- Films: rouleaux formation
- U and Es: increased calcium, urea, creatinine
- xray: lytic punched out lesions. Salt and pepper skull
- serum/urine electrophoresis: Bence Jones Proteins
- bone marrow biopsy: increased plasma cells
what do most cases of multiple myeloma develop from?
MGUS (pre malignant stage)
what are causes of microcytic anaemia? (low MCV)
Iron deficiency, anaemia of chronic disease, thalassemia
What are causes of normochromic anaemia?
Acute blood loss, anaemia of chronic disease, haemolytic anaemia
What are causes of macrocytic anaemia?
Megaloblastic, vitamin B12 deficiency, alcohol, liver disease, hypothyroidism
What do reticulocytes indicate?
- reticulocytes are young RBCs recently released from bone marrow
- reticulocyte count: guide to erythroid activity.
- increases after haemorrhage, haemolysis
Where is most of the body’s iron absorbed? What factors promote iron absorption?
duodenum. Factors that promote iron absorption: gastric acid, iron deficiency, increased EPO activity
How is B12 absorbed?
liberated from protein complexes y gastric acid and pepsin, then binds to intrinsic factor, formed by parietal cells
What is the presentation of iron deficiency anaemia?
- microcytic - brittle hair and nails -atrophic glossitis (tongue papillae worn down) -angular stomatitis (ulcers)
- HIGH total iron binding capacity in blood
What is the causes of iron deficiency anaemia?
blood loss, increased demands (growth and pregnancy), decreased absorption, poor dietary intake
What is pernicious anaemia, causes and its presentation?
- low B12, macrocytic anaemia
- causes: autoimmune conditions can mean destruction of parietal cells. Also impaired absorption and low B12 in the diet
- presentation: neurological defects (peripheral neuropathy, but spinothalamic tract intact). Lethargy, fatigue, dyspnoea, faintness.
What is the treatment of pernicious anaemia?
B12 injection: hydroxocalamin (IM)
What is the presentation of folate deficiency, and how long does it take to develop?
- general anaemia presentation, and glossitis and depression. Macrocytic anaemia (folate needed for Hb DNA maturation)
- takes 4 months to develop, as body has 4 month reserve
What are the causes of folate deficiency?
poor intake (old age, poverty, alcohol excess), malabsorption (coeliac disease, Crohn’s), excess utilisation (pregnancy, malignant and inflammatory disease). Some drugs
What are general anaemia symptoms:
fatigue, lethargy, dyspnoea, palpitations, headache, pallour
What is the presentation of haemolytic anaemia, and what are examples of it?
- examples: sickle cell anaemia, thalaessmia
- presentation: jaundice, gallstones, leg ulcers
What is the pathophysiology/aetiology of haemolytic anaemia?
RBC destroyed before normal 120 day lifespan. Destruction can be intravascular or extravascular
- aetiology: inherited –> red cell membrane fect (sphereocytosis), haemaglobin abnormalities, metabolic defects
- -> acquired: autoimmune, infections (eg, malaria), systemic failure (liver failure)
What is the dx for haemolytic anaemia?
Reduced Hb, increased MCV, increased reticulocytes, spherocytes
What is the tx for haemolytic anaemia?
folate acid and iron supplement. Immunosuppression if immune cause. splenectomy if all else fails
What is aplastic anaemia? what is the presentation?
- bone marrow failure, due to reduction in number of pluripotent stem cells, leads to lack of haemopoesis
- presentation: increased susceptibility to infection and bleeding gums and nosebleeds
What is pancytopenia?
low red blood cells, white blood cells and platelets
What is the dx of aplastic anaemia? Tx?
- FBC: pancytopenia, low reticulocytes
- biopsy of bone marrow: hypocellular marrow with increased fat spaces
- Tx: blood and platelet transfusion. immunosuppression., bone marrow transplant
What is sickle cell anaemia?
inherited haemolytic anaemia. Deformation of faulty Hb molecule. Leads to HbS. In deoxygenated state, HbS are insoluble and polymerise, leading to sickling. Can lead to haemolysis and vaso-occlusion
- autosomal recessive, more common in africa
What is the presentation of sickle cell anaemia?
- foetal haemaglobin is normal, so presents when this is out of circulation at 6 months
- vaso-occlusion: early childhood acute pain in feet and hands due to occlusion of small vessels. Avascular necrosis of bone marrow. Affects (in adults) long bones, ribs, spine, pelvis
- retinal ischaemia
- often symptoms of anaemia as HbS release oxygen early
What is the treatment of SCA?
- avoid precipitating factors
- folic acid supplements
- NSAIDs
- BMT from HLA matched siblings
What is thalassemia?
One or multiple gene defects leading to reduced rate of production of globin chains. Can be alpha or beta thalassemia depending on which is affected. Unbalanced Hb synthesis, so unmatched globins precipitate, damaging RBC membranes, causing damage
What is the presentation of thalassemia?
- alpha presents in utero. excess beta chains
- beta presents in infancy. excess alpha chains
- asymptomatic if heterozygote
- severe anaemia in homozygotes
- failure to thrive, bone deformities
- iron overload
How is thalassemia diagnosed? What is the tx?
- dx: Hb electrophoresis
- tx: blood transfusion to avoid compx. Iron chelating agent for overload. Ascorbic acid increases iron excretion in urine, to offset overload
What is glucose-6-phosphate dehydrogenase deficiency?
G6PD is an enzyme that maintains glutathione in a reduced state. This protects against oxidant injuries in the RBC. Thus, increased G6DP leads to increased haemolysis.
What is the presentation of G6PD deficiency? what is the tx?
neonatal jaundice, haemolytic anaemia, acute haemolysis (precipitated by fava beans)
- tx: avoid fava beans. Transfusion if necessary
What is the inheritance of G6PD deficiency?
x-linked recessive
What is polycythaemia Rubra Vera?
most common myeloproliferative disorder. Type of blood cancer. Excess production of RBC, WBC and platelets: increased viscosity of the blood.
What is a myeloproliferative disorder?
uncontrolled clonal proliferation of cell lines: namely erythroid, myeloid, megakaryocyte lines. Differentiation from leukemia as there is no accumulation of abnormal product.
What is the genetic mutation in myeloproliferative disorders?
Group of stem cell disorders that share mutations to JAK2, which leads to prolonged survival of RBC
What is the presentation of polycythaemia rubra vera?
Signs and symptoms due to hypervolaemia and hyperviscosity.
- pruritus (urge to itch), especially after exposure to warm water. Headaches. Dizziness. Sweating.
- thrombotic compx: MI, stroke, DVT
- sometimes erythromelalgia (sudden, severe burning in hands and feet with red/blue discolouration)
What is the dx and tx of polycythaemia rubra vera?
- dx: blood count showing increased WBC, platelets and red cell volume. Gain of function JAK-2 mutation. Decreased serum EPO
- Tx: low dose aspirin. Myelosuppression (hydroxycarbamide). Venesection
What can polycythaemia rubra vera transform to?
acute myeloid leukaemia
What is the composition of a DVT?
RBC and few platelets. Forms in direction of blood flow
What is the Dx of DVT?
USS, d-dimers, contrast venography
What is disseminated intravascular coagulation?
acquired coagulation disorder, alongside vitamin K deficiency. Leads to widespread intravascular deposition of fibrin with consumption of coagulation factors and platelets. Then associated haemorrhagic or thrombotic syndromes as platelets used up
What is the aetiology of DIC?
secondary to many things that cause cytokine release: systemic inflammatory response syndrome, sepsis, septic shock, multiple organ dysfunction, malignancy, trauma. Major trigger: exposure of blood to a potent tissue factor: eg, brain tumour, placental rupture