Haemotology Flashcards
Where are RBCs produced and where are they disposed?
Bone marrow
Spleen and liver
Name 3 functions of RBCs
Carry Hb
Generate ATP
Maintain osmotic pressure
What is a normal Hb level for a male and female?
M - 130-180 g/L
F - 115-165 g/L
Name 3 factors in which ‘normal’ Hb levels can vary?
Age
Sex
Ethnicity
What is the definition for anaemia?
Where Hb conc is less than normal range
Name some general underlying mechanism for anaemia
Abnormal RBC production Abnormal Hb synthesis Abnormal mature RBC structure, function, metabolism Excessive blood loss Abnormal reticuloendothelial system
Explain how the reticuloendothelial system works
O2 levels reduce, kidneys release erythropoietin, stimulates RBC production and reduces apoptosis in bone marrow, RBC levels rises (and 02)
Negative feedback
Explain the significant of reticulocyte count
Reticulocyte = immature RBC
Gives to clue to anaemia cause
If low - problem with bone marrow?
If normal - RBCs being destroyed later on?
What is the definition of microcytic, normocytic and macrocytic anaemias?
Mic - small RBCs
Nor - nor sized RBCs
Mac - large RBCs
Name two conditions in which you would find macrocytic RBCs.
Myelodysplastic syndromes
Vit B12 / folate deficiency
In what condition would you find microcytic RBCs?
Thalassaemia
What condition would you find teardrop shaped RBCs?
Myelofibrosis
Where would you find Howell - Jolly RBCs?
In patients with a splenectomy
Microscopically, what would you observe of the RBCs of Vit B12 or folate deficient patients?
Megablastic RBCs
Large nuclei and open chromatin (cannot synthesis DNA), cytoplasm small
Macrocytic RBCS
What would you observe of the RBCs of a patient with Thalassaemia?
Target cells
Hypochromic RBCs
Microcytic RBCS
Large nucleated RBCs
What is haemolytic anaemia?
Anaemia of high RBC destruction
Name 3 causes of haemolytic anaemia.
Autoimmune HA
Myelofibrosis
Anaemia of chronic disease
What investigations would you ask for in haemolytic anaemia?
Bilirubin
Reticulocyte count
Macrophage count
What are some signs and symptoms of Vit B12 / Folate deficiency?
Low mood Fatigue Pallor Neurological signs - depression, dementia Jaundice
What investigations would you ask for in a suspected Vit B12 / Folate deficiency?
Vit B12 and folate count Hb level Mean cell volume WBC count Platelets
How does anaemia of chronic disease differ from iron deficiency?
AOCD - Associated with inflammatory conditions and chronic disease.
Increase macrophage production - increased RBC destruction.
Increased cytokines - increased Hepcidin - reduces iron absorption.
Iron deficiency - due to insufficient intake, poor absorption, increase use - not increased destruction
What are some microscopic markers of iron deficiency?
Hypochromic RBCS
Microcytic (low MCV)
Pencils cells, target cells
Change in size and shape (anisopoikilocytosis)
What is the gold standard test for diagnosing iron deficiency?
Reticulocyte haemoglobin content (CHR)
How would you treat an iron deficiency?
Dietary advice
Oral supplements
Intramuscular injections
Transfusions
Some signs and symptoms of iron deficiency?
Tiredness Pallor Exercise intolerance Tachycardia Angina Respiratory changes - smooth nails Increased resps
What is Polycythaemia?
High conc RBCs
High haemocrit
What is Polycythaemia Vera?
Cancer Bone marrow produces too much RBCs and haemocrit Leads to blood thickening Can lead to hypoxia, gout. Treatment - venesection, aspirin
What are some functions of the spleen?
RBC recycling
Phagocytosis
Immune functions
Stem cell proliferation
Name some causes for splenomegly.
Myelofibrosis
Leukaemia
Endocarditis, Hepititis (infection)
Viruses e.g. Glandular fever
What can splenomegly lead t?
Portal hypertension
Increased RBC production
Cancer
What is leucopenia?
Low WBC count
What is leucocytosis?
Increased WBC count
What are some common causes for neutrophilia?
Smoking Cancer Inflammation Tissue damage Myeloproliferative disease
What are some reason for neutropenia?
Reduced production - B12/folate deficiency, aplastic anaemia, viruses, chemo
Increased removal - sepsis, splenic pooling
What are some reasons for eosinophilia?
Parasitic infection
Allergic disease - Asthma, hay fever
Hodgkin Lymphoma
Myeloproliferative conditions
What is pancytopenia? What are some signs and symptoms?
Reduction in WBCs, RBCs, platelets
Fatigue, shortness of breath, thrombocytopenia (bleeding, bruising) , neutropenia (infection)
How would pancytopenia look microscopically?
High number of fat cells to other cells ratio