BLOOD Flashcards
(32 cards)
DEFINE ANAEMIA
Decreased:
> erythrocytes
> hemoglobin
> hematocrits
all below their normal ranges
ETIOLOGY OF ANAEMIA
> haemorrhage
destruction of RBC
decreased production in bone marrow > hematopoeisis is low
WHAT CAUSES LOW HEMOGLOBIN?
> Low diet of IRON
> genetic + acquired conditions that affect production + function/ structure of Hb
CLASSIFICATION OF ANAEMIA DUE TO HAEMORRHAGE?
> Acute blood loss > acute post hemorrhagic anaemia
> chronic blood loss
CLASSIFICATION OF ANAEMIA DUE TO RBC DESTRUCTION?
> inherited genetic defects
> acquired genetic defects
> Ab mediated destruction
> mechanical trauma
CLASSIFICATION OF ANAEMIA DUE TO DECREASED RBC PRODCUTION IN BONE MARROW?
> inherited genetic defects
> defects leading to stem cell depletion (aplastic anaemia)
> defects affecting maturation of RBC (thalassemia)
> nutritional deficiencies
> deficiencies affecting synthesis of DNA (via B12 deficiency anaemia)
> deficiencies affecting Hb production (iron deficiency anaemia)
> bone marrow failure due to systemic disease
> inflammatory, infectious disease, renal failure, cancer)
WHAT ARE THE RESULTS OF ANAEMIA?
TISSUE HYPOXIA
> RBC carry O2 to tissue cells so reduces RBC»_space; low O2 supply to tissue cells > hypoxia
> prolonged anaemia > CHRONIC HYPOXIA
> CHRONIC HYPOXIA > tissue + organ damage > FATTY LIVER > FATTY HEART > FATTY BONE MARROW
WHICH ORGANS ARE AFFECTED IN ANEMIA + HOW?
> FATTY LIVER
> FATTY HEART
> FATTY BONE MARROW
DESCRIBE FATTY LIVER IN ANEMIA?
FATTY LIVER = STEATOSIS
> too much fat build up in liver
> hypoxia in liver tissue due to anemia > unable to break down fat build up
MACRO:
> ENLARGED
> YELLOW
> SOFT + GREASY
MICRO:
> fat as vacuoles
> displaces nucleus to periphery of hepatocytes
DESCRIBE FATTY HEART IN ANEMIA?
TIGER HEART
> bands of yellow affected myocardium + bands of darker red brown unaffected myocardium
> papillary muscles affected in right ventricles
intracellular deposits of fat along small venues
DESCRIBE FATTY BONE MARROW IN ANEMIA?
INACTIVE FAT BONE MARROW replaces by red, hematopeotic bone marrow
OUTLINE CLINCIAL FEATURES OF ANEMIA
> cyanosis > pallor > tachycardia > palpitation > dyspnoea > dizziness > weakness + fatigue > glossitis
ALL DUE TO LOW OXYGEN > HYPOXIA
ETIOLOGY OF ANAEMIA DUE TO BLOOD LOSS?
> trauma + rupture to blood vessels > increased menstruation > GI bleeding > gastric/ duodenal ulcer > varices of esophagus > genital system disease > childbirth trauma
MORPHOLOGY OF ANEMIA DUE TO HEMORRHAGE?
> blood loss
low erythrocytes
increased erythropoeisis in bone marrow after 48-72h
CHRONIC BLOOD LOSS
> development of IRON deficiency anaemia
WHAT TYPE OF ANEMIA DOES HEMORRHAGE CAUSE?
IRON DEFICIENCY ANAEMIA
OUTLINE CHARACTERISTICS OF IRON DEFICIENCY ANEMIA?
> smaller erythrocytes > microcytic
hypo chromic
bone marrow regeneration > red bone marrow replaces yellow inactive bone marrow
WHAT IS MEGALOBLASTIC ANAEMIA?
ERYTHROCYTES EXTREMELY LARGE BUT LOW IN NUMBERS
> macrocytic
> due to defective DNA synthesis leading to delayed maturation of RBC nucleus
ETIOLOGY OF MEGALOBLASTIC ANAEMIA?
> Vitamin B12 deficiency - cobalamin
Vitamin B9 deficiency - Folate
pernicious anaemia
WHAT IS PERNICIOUS ANAEMIA?
> autoimmune disorder
inability of gastric mucosa to produce intrinsic factor (IF)
antibodies:
> anti-parietal antibodies against parietal cells of stomach mucosa
> anti-intrinsic factor antibodies
intrinsic factor = important for absorbing + transferring vitamin B12 across intestinal mucosa
vitamin B12 - important for healthy RBC
CLINICAL FEATURES OF PERNICIOUS ANEMIA?
> fatigue
dyspnoea
tachycardia
> NEUROLOGICAL > Vit.B12 maintains integrity of myelin sheaths
> NERVOUS SYSTEM DYSFUNCTION
parathesia (burning, prickling sensation)
loss of proprioceptive ability
ataxia ( no coordination)
hunters glossitis (painful, tender, glossy tongue)
MORPHOLOGY OF MEGALOBLASTIC ANEMIA?
Blood: macrocytic + oval shaped
Bone marrow: hyper cellular due to increased erythropoiesis > producing abnormal large RBC cells with mature cytoplasm + less mature nuclei
Stomach > chronic gastritis > atrophy of fundic glands stomach > affected chief + parietal cells >> producing low intrinsic factors > affecting with Vit. B12 absorption
Nervous system:
> central nervous system lesion
> demyelination of dorsal + lateral tracts sometimes with loss of axons
ETIOLOGY OF IRON DEFICIENCY ANAEMIA?
- Increased blood loss - haemorrhage
- Increased demand during periods of increased growth
- infancy
- childhood
- adolescence
- premature children
- pregnancy + lactation - Inadequate dietary intake
- poor economic status
- anorexia
- elderly due to poor dentition
- apathy - Decreased absorption
- partial/ total gastectomy
- achlorhydria
- intestinal malabsorption
OUTLINE WHAT CAUSES INCREASED BLOOD LOSS FOR IRON DEFICIENCY ANEMIA?
> UTERINE
- menstruation
- repeated miscarriages
- post menopausal uterine bleeding
> GIT
- peptic ulcer
- haemorrhoids
- hookworm infestation
- cancer of stomach + large bowel
- oesophageal varices
- hiatus hernia
- chronic aspirin ingestion
- ulcerative colitis
- diverticulosis
> RENAL
- hematouria
- hemoglobinuria
> NASAL
- epistaxis
> LUNGS
- hemoptysis
EXPLAIN PATHOGENISIS OF IRON DEFICIENCY ANAEMIA?
> Inadequate supply of iron for required Hb synthesis
> negative iron balance > compensated by mobilisation of iron from tissue deposits > maintains Hb synthesis
> depletion of iron deposits in tissue > IRON DEFICIENCY ANEMIA
