Hematology Flashcards
Components of Blood
Plasma
Buffy coat
Erythrocytes
Function of leukocytes
destroy microorganisms at site of infection, remoce foreign substances and body debris
classification of WBCs (leukocytes)
granulocytes eosinophils basophils mast cells neutrophils
dendritic cells
involved in stimulating immune system
polycythemia
an increase in RBCs due to drug doping, physiological factors (altitude, hypoxic disease), genetic abnormaility in Hb O2 release, disease related
symptoms of polycythemia
headache, vertigo, enlarged spleen, liver, itchiness, reddish skin, ringing in ears
anaemia
reduction in total number of erythrocytes
decrease in quality and quantity of haemoglobin
decrease in hematocrit
causes of anaemia
blood loss, decrease production of RBC, altered haemoglobin synthesis, altered DNA synthesis, stem cell dysfunction, bone marrow infiltration, renal disease
diagnosis of anaemia
hematocrit, size of RBC, colour of RBCs, MCV (measure of cell size, MCH (concentration meausres Hb production
Iron deficiency symptoms
difficulty swallowing, lesions may progress to malignancy, enzyme changes, mental confusion, memory loss, increased infections
pernicious anaemia
caused by vitamin B12 deficiency
normocytic anaemia
increased RBC destruction
blood loss
increased haemolysis
thalassaemia
inherited autosomal recessive blood disorder
weakening and destruction of red blood cells
less haemoglobin
major thalassaemia - major
impairs growth, produces skeletal abnormalities of maxilla and frontal bone
extramedullary haematopoiesis in liver and spleen
bronze coloured skin
changes in gonads
progresses to death before age 20
Haemorrhage
loss of blood escaping from the circulatory system
Can be internal or external
Haemostasis
stopping or controlling of bleeding
- vasospasm: constriction of blood vessels, first response to injury, chemicals released by endothelial cells and platelets
- formation of platelet plug
- activation of coagulation cascade: platelets form temporary plug, clotting factors activate factor X (thrombin), converts fibrinogen to fibrin
- formation of clot
- clot retraction
Coagulation defects
defects or deficiencies of clotting factors
large ecchymoses or haemotomas into GIT, urinary tract and joints after injury or surgery
Haemophillia A
genetic deficiency in clotting factor VIII
causes increased bleeding, inherited as X-linked
can lead to joint deformity
Von Willebrand disease
hereditary deficiency of factor VIII:vWF
Haemphillia B
christmas disease (hereditary deficiency of factor IX x-linked recessive variable effect ranging from asymptomatic to severe haemorrhage as in haemophillia A
signs and symptoms of haemophillia B
prolonged bleeding from cuts, wounds or during surgical procesures
unexplained excessive bruising or nose bleeds
unexplained blood in faeces or urine
pooling of blood in joints
Haemophilia C
hereditary deficiency of factor XI
Leukaemia
cancer of white blood cells and their precursers
bone marrow makes abnormally larage number of immature white blood cells - blasts or leukaemia cells
results in: neoplastic cells in peripheral blood, suppression of other marrow elements leading to symptoms of lack of RBC, WBC, platelets
symptoms of leukaemia
weight loss fever frequent infections short of breath muscular weakness pain or tenderness in bones and joints fatigue loss of appetite night sweats easy bleeding and bruising speen and or liver enlargement
types of laeukaemia
acute lymphocytic leukaemia (ALL)
acute myelogenous laekaemia (AML
chronic lymphocytic leukaemia (CLL)
chronic myelogenous leukaemia (CML)
Acute lymphoblastic leukaemia
leads to overproduction of immature WBCs which leads to lymphoblasts
causes of ALL
exposure to very high doses of radiation, industrial chemicals, certain types of infections
Chronic lymphoblastic leukaemia
slow growing, affects immature B cells
it is incurable
ACute myelogenous laukaemia
overproduction of immature WBC (myeloblasts)
overcrowding in bone marrow
symptoms of AML
anaemia fever bleeding hepatosplenomegaly no significant lymphadenopathy
Chronic myelogenous laukaemia
increased proliferation of the graanulocytic cell line without the loss of their capacity to differentiate
leads to increased myeloid cells, erythroid cells and platelets in blood and marked myeloid hyperplasia in the bone marrow
originate in single abnormal haematopoietic stem cell
Causes of Leukaemia
high level of radiation viruses genes chemicals mostly unknown
TReatment of Leukaemia
chemo immunological products radiation bone marrow transplant drugs, TK inhibitors
Lymphoma
malignant neoplastic lymphocytes = downstream unlike leukaemia
cancer of lymphatic system - lymph nodes
tend to be solid tumours
Non-Hodgkin’s lymphoma risk factors
environmental agents, irradiation, chemicals, anti-neoplastic agents inherited genetic abnormalities more common in males >50 yrs immunosuppression (transplants, AIDS) EBV virus
Non-Hodkin’s lymphoma symptoms
painless firm lymphademopathy fever, night sweats, weakness weight loss eosinophila pleural effusion abdo pain splenomegaly
Burkitt’s lymphoma
most common paed malignant tumour mostly occurs in africa and new guinea caused by epstein-barr virus often in the jaw area closely packed B cells in the affected lymph nodes
Hodgkin’s lymphoma
originates from lymphocytes
history of EBV increases risk
characterised by the orderly spread of disease from one lymph node group to another and by the development of systemic symptoms with advanced disease
Symptoms of hodgkins lymphoma
enlarged painless mass in neck
mediastinal mass on xraay
mediastinal growth can affect lungs, trachea, bronchi, pleaura, nerves, spinal cord, ureters
skin lesions, itching, scratching
fever, night sweats, loss of 10% body weight
treatment of hodgkins lymphoma
radiation
chemo
hematopoietic stem cell transplantation
