l3 Flashcards
what is Anaemia?
and what clinical consequence does it have?
when the Haemoglobin level falls below defined levels.
Insufficient o2 delivery
what are the causes of anaemia ?
A decrease: in RBCs
Haemoglobin content
and altered haemoglobin content doesn’t carry sufficient o2
What are the symptoms?
Koilonychias-spoon shaped finger nails Lethargy Shortness of breath Palpitations Headaches Non-specific
what are the signs?
Pale conjunctivae
Tachypnoea-breathing
Tachycardia-heart rate
What are the 5 main broad causes?
Bleeding Deficiency in Fe, B12, folic acid Haemolytic Bone marrow dysfunction poor o2 saturation
3 other minor causes?
Diet
Increased requirements-Pregnancy
Poor O2 utilisation
Which 3 categories can help classify anaemia?
Size of the red blood cells
Acute/ chronic
other underlying aetiology
What can cause Fe deficiency?
Bleeding
nutrition
Increased requirements
What diagnostic tests can be done to confirm suspicions?
Serum Ferritin-storage form of Fe
Serum Fe- Labile as reflects recent intake of iron
Serum Transferrin-Carrier molecule for Fe, Homeostatically goes up if Fe deficient.
% Transferrin saturation- Sensitive
Blood film-quick and easy
what do we measure in the category of size of red blood cell?
Mean Corpuscular volume
what describes the 3 size states of red blood cells and any info on them?
Microcytic -small: Fe deficiency Thalassaemia indicator Macrocytic-large: B12 and folate deficiency Myelodysplasia Normocytic-normal
What does myelodysplasia mean?
Group of disorders caused by poorly formed cells
what is a reticulocyte count?
Represents RBC production rate by bone marrow
What 2 reasons would the count be low?
1) bone marrow is infiltrated
2) Precursor deficiencies
What 2 reasons would cause the count to be high
Haemolysis
chronic bleeding
what if they are in normal range but are anaemic
Bone marrow is not responding appropriately
How is it measured
Flow cytometry- count nucleic acid
What ae the 4 features of the blood film diagnosis?
Hypochromia- Pale red blood cells
Microcytosis- Small rbcs
Pencil cells-cigar shaped
Target- cells with dark centres
what 3 things classify is megaloblastic anaemia
when Macrocytic cells are above 100
B12 and Folate deficiency
Insufficient Reticulocyte precursors for cell division
What does B12 and Folate contribute to making
DNA Nucleotides
Info on B12 Deficiency
Dietary Malabsorption Crohns disease pernicious anaemia: -autoimmune -Intrinsic factor
what is crohns disease?
Inflammatory bowels disease affecting lining
Folate deficiency?
Dietatry Malabsorption Excess utilisation:-pregnancy Alcohol Drugs
Causes of chronic anaemia
Chronic: -Inflammation -Infection Autoimmune Rheumatoid arthritis Cancer
3 Main causes of chronic anaemia
1) Poor utilisation of Fe in body:
stuck in macrophages of reticuloendothelial system
and so can’t be mobilised by erythroblasts
2) Dysregulation of Fe homeostasis
- decreased transferrin
- Increased hepodin
3) Impaired proliferation of erythroid progenitors
-Fe unavailable
-n response to erythroprotein
Information on sickle cell anaemia?(3)
Point mutation in Beta globin gene causing Hbs
Autosomal recessive
Forms long spiky filamentous strand which is insoluble at low o2 tensions, leading to crisis
Effects of sickle cell anaemia
low blood o2 levels
Vaso-occlusive
Ischemia-pain
Managing SCA
Hydration
transfusion
What is Thalassaemia
& Clinical features
detection
When there is insufficient Hb produce Due to altered gene expression Bones misshapen enlarged spleen liver and heart Blood film
What are the 3 causes of bone marrow infiltration
Leukaemia: Bone marrow failure Lymphoma: Lymphadenopathy Weight Loss Myeloma: Anaemia Hyperkalaemia Renal failure
where to take a bone marrow biopsy/aspiration
iliac crest
Management of acute anaemia (1)
Transfusion
Management of chronic anaemia
Fe Supplement-oral
Folic acid -oral
B12- injections
Erythroprotein in patients with kidney failure
Why avoid long term transfusion for patients with chronic anaemia
Fe overload
May cause alloimmunity and antibody production against it
Symptoms of acute anaemia
Melena-dark stools
Hematemesis-vomiting
