Pernicious Anaemia Flashcards
What is pernicious anaemia?
It is defined as an autoimmune condition in which there is antibody formation against gastric parietal cells ± intrinsic factor – resulting in reduced vitamin B12 absorption
What is the most common cause of vitamin B12 deficiency?
Pernicous Anaemia
Describe the physiological process of intestinal vitamin B12 absorption
It is dependent upon intrinsic factor, which is a protein produced by gastric parietal cells
There is binding between vitamin B12 and intrinsic factor, resulting in the formation of the IF-B12 complex, which can then be absorbed by the distal ileum
What are the two functions of vitamin B12?
Red blood cell production
Myelination of nerves
Describe the pathophysiology of pernicous anaemia
There is antibody formation resulting in reduced intrinsic factor binding sites or reduced intrinsic factor production, ultimately leading to reduced vitamin B12 absorption
This results in the development of megaloblastic anaemia and neuropathy
What four risk factors are associated with pernicous anaemia?
Middle Aged
Female Gender
Autoimmune Disorders
Blood Group
What are the eleven clinical features of pernicous anaemia?
Fatigue
Pallor
Dizziness
Dyspnoea
Palpitations
Jaundice
Glossitis
Paraesthesia
Muscle Weakness
Poor Concentration
Memory Loss
In pernicious anaemia, individuals present with a lemon tinge to their skin. Explain
This is due to the combination of mild jaundice and pallor
What is glossitis?
It is defined as an inflammed, sore and smooth tongue
What two investigations are used to diagnose pernicous anaemia?
Blood Tests
Blood Film
What seven blood test results indicate pernicous anaemia?
Decreased Haemoglobin Levels
Increased MCV > 100
Decreased WBC Levels
Decreased Platelet Levels
Decreased Vitamin B12 Levels < 200
Positive Anti-Intrinsic Factor Antibodies
Positive Anti-Gastric Parietal Cell Antibodies
Which is the gold standard antibody test used to diagnose pernicous anaemia?
Anti-Intrinsic Factor Antibodies
What are the two features of pernicous anaemia on blood film?
Hypersegmented Polymorphs
Oval Macrocytes
What are the two pharmacological management options of pernicous anaemia?
Vitamin B12 Replacement
Folic Acid Supplementation
What is the gold standard management option of pernicious anaemia?
Vitamin B12 Replacement
Describe the vitamin B12 replacement treatment course used to manage pernicous anaemia - in the absence of neurological features
It involves administration of three intramuscular 1mg hydroxocobalamin injections per week for 2 weeks, followed by administration every 3 months
Describe the vitamin B12 replacement treatment course used to manage pernicous anaemia - when there is development of neurological features
It involves administration of intramuscular 1mg hydroxocobalamin injections every other day until features are resolved
When are folic acid supplements used to manage pernicous anaemia?
When there is development of folate deficiency
When there is development of both vitamin B12 and folate deficiency, which should be corrected first? Explain
Vitamin B12 deficiency
In order to prevent subacute combined degeneration of the spinal cord
What are the four complications associated with pernicious anaemia?
Peripheral Neuropathy
Subacute Combined Spinal Cord Degeneration
Neuropsychiatric Disorder
Gastric Cancer
