Sponsors

You're browsing as an anonymous user. Join the community today to view notes at your university, edit pages, and share knowledge!

Anaemia

From Mediwikis

Reduced ability of the red blood cells to carry oxygen

 Clinical Features

  1. Shortness of breath on exertion
  2. Palpitations
  3. Weakness, lethargy
  4. Headaches
  5. Heart failure symptoms
  6. Vascular symptoms
  7. Visual disturbances

Signs

  1. Pallor of mucous membranes
  2. Hyperdynamic circulation
  3. Tachycardia, bounding pulse, systolic flow murmur
  4. Congestive cardiac failure
  5. Retinal haemorrhages
  6. Specific signs (koilonychia)

Normal Values and Requirements

Average child needs 1.1g Fe

Male

  • 0.5-1g Fe
  • 135-175 Hb(g/L)
  • 0.40-0.52 % RBC
  • 80-95 MCV (fl)

Female

  • 0.5 - 3g Fe depending on menstruation and pregnancy

115-155 Hb(g/L)

  • 0.36-0.48 % RBC
  • 80-95 MCV (fl)

Microcytic- MCV <76 fL

 Causes

IDA (iron deficiency anaemia) - IDA is not a diagnosis

  • Increased demands from growth/pregnancy
  • Coeliacs disease
  • Poor diet, uncommon due to humans only absorbing a small percentage of iron in their diets anyway

Thalassemia - abnormal haemoglobin chain production

Chronic diseases (those with blood loss or GI absorption problems)

Other

Normocytic-MCV 80-100 fL

Caused by:

  • Anaemia of chronic disease
  • Sickle Cell Disease
  • Haemolysis/ haemorrhagic anaemia
  • Pregnancy

Macrocytic- MCV >100 fL

Causes

 Pernicious Anaemia

B12 deficiency anaemia associated with neuropathy caused by:

  1. Lack of intrinsic factor
    1. Autoantibodies to IF (50% of PA cases)
  2. Crohn's disease
  3. Ileal resection

Folate Deficiency Anaemia

B9 deficiency anaemia NOT associated with neuropathy caused by:

  1. Pregnancy
  2. Haemolysis
  3. Coeliacs
  4. Alcoholism (Dietary deficiency)

Haemolytic Anaemia

Haemolytic anaemia can be acquired or hereditary, and involved the premature breakdown of RBCs before their normal lifespan of ~120 days.

Acquired haemolytic anaemia can be caused by:

  • Drug induced: formation of RBC autoantibodies or production of immune complexes
  • Autoimmune haemolytic anaemia: 'Warm' type may be caused by SLE, CLL, lymphoma. 'Cold' type can be caused by cold haemagglutinin disease or viral infections (i.e. EBV)
  • Infection (i.e. malaria, blackwater fever)
  • Trauma
  • DIC

Hereditary haemolytic anaemia can be due to:

  • Membrane defects
    • Hereditary spherocytosis
    • Hereditary elliptocytosis
  • Enzyme defects
    • Glucose-6-phosphate dehydrogenase (G6PD) deficiency
    • Pyruvate kinase deficiency
  • Haemoglobinopathies
    • Sickle cell disease
    • Thalassaemia

Aplastic Anaemia

This is a rare stem cell disorder causing pancytopenia and hypoplastic marrow. It can be caused by infections, drug reactions, autoimmune pathology or irradiation. It may also be inherited in the form of Fanconi Anaemia.