Anaemia Flashcards
What is anaemia?
A decreased haematocrit (HCT/Hct)/packed cell volume (PCV) or haemoglobin (Hb)
Anaemia indicates a deficiency in red blood cells or hemoglobin in the blood.
How is haematocrit calculated?
HCT = (MCV x RBC count) + 10
HCT can be affected by machine errors.
What is PCV?
A directly measured percentage of packed red cells in blood volume
PCV can be affected by how RBCs pack together.
What are some signs that may indicate anaemia during a clinical examination?
- Inadequate perfusion/oxygenation
- Compensatory mechanisms
- Other signs
- Signs related to underlying pathology
Examples include pale mucous membranes, lethargy, tachycardia, and splenomegaly.
What is apparent (non-pathological) anaemia?
Anaemia observed in young animals, anaesthesia, or overhydration
It is not caused by underlying pathology.
What does categorizing anaemia help with?
It helps diagnose the cause and monitor the condition
Severity categorization can guide clinical decisions.
What are RBC indices?
- Mean corpuscular volume (MCV)
- Mean corpuscular haemoglobin concentration (MCHC)
These indices categorize RBCs by size, color, shape, and cellular contents.
What indicates regeneration in anaemia?
The presence of reticulocytes and anisocytosis
Nucleated RBCs and Howell-Jolly bodies are also indicators.
What is non-regenerative anaemia?
Decreased bone marrow production of RBCs or pre-regenerative anaemia
It can occur due to chronic conditions or nutritional deficiencies.
What are some common causes of RBC destruction?
- Toxicity
- Infection
- Immune-mediated issues
- Mechanical damage
These can lead to haemolysis.
What is the most common form of non-regenerative anaemia in small animal practice?
Anaemia of inflammation (chronic disease)
This type is usually normocytic and normochromic.
What clinical signs are associated with anaemia?
- Pallor
- Icterus
- Tachycardia
- Tachypnoea
- Weak pulses
- GI signs (e.g., melaena)
Severity of signs can vary with the speed and volume of blood loss.
How do you diagnose the cause of anaemia?
- History and clinical examination
- Severity assessment
- Regenerative status
- Presence of abnormal RBCs
Important clues include signs of bleeding or known toxic exposures.
What are the emergency treatments for anaemia?
- Triage and stabilization
- Fluid therapy
- Blood product transfusion if needed
Treatment should address underlying causes such as haemorrhage or haemolysis.
What is the role of fluid therapy in treating anaemia?
To treat hypovolaemia and improve tissue perfusion
IV fluid therapy is essential during the peracute period.
What are some treatments for haemorrhage in anaemia?
- Diagnose and treat coagulopathy
- Physically stop bleeding
- Address internal causes (e.g., GI diseases)
This may include using GI protectants or performing surgical interventions.
True or False: All blood loss is initially regenerative.
False
All blood loss is non-regenerative to start with.
What are spherocytes?
Sphere-shaped RBCs lacking central pallor, smaller and denser than normal RBCs
Commonly associated with immune-mediated hemolytic anaemia (IMHA).
What is the significance of schistocytes on a blood smear?
Indicates mechanical injury and possible vascular damage
Associated conditions include DIC and glomerulonephritis.
What does microcytosis with anisocytosis indicate?
Increased zone of central pallor, suggestive of hypochromic anaemia
This finding can indicate iron deficiency.
Fill in the blank: The most common cause of haemolysis seen in clinical practice is _______.
[Immune-mediated hemolytic anaemia (IMHA)]
It involves a reaction to normal self-antigens.
What are the types of blood products mentioned?
Whole blood, pRBCs, FFP/FP, platelets
Platelets help in the moment but don’t increase platelet count in the long term.
What should be diagnosed and treated in cases of haemorrhage?
Coagulopathy
If possible, physically stop the bleeding and address internal causes.
What are examples of internal causes of haemorrhage?
- GI diseases (melaena, haemorrhagic D+, haematemesis)
- Genitourinary diseases (urinary or reproductive losses)
- Intracavitary bleeding
Treatment may include surgery, GI protectants, or addressing coagulopathy.
What is the first line treatment for immune-mediated hemolytic anemia (IMHA)?
Glucocorticoids
Adjunct agents may be required if response is not favorable.
Name some adjunct agents for IMHA if glucocorticoids are insufficient.
- Azathioprine
- Mycophenolate Mofetil
- Ciclosporin
- Leflunomide
What infectious disease is known to cause anaemia via haemolysis?
Babesia
It is transmitted by ticks and is an intracellular protozoon.
What are the clinical signs of Babesia infection?
- Pallor
- Jaundice
- Pyrexia
- Haemoglobinuria
- CV compromise
- Weakness
- Inappetence
What treatments are effective for Babesia infection?
- Imidocarb (unlicensed)
- Azithromycin
- Doxycycline
- Supportive treatment (including transfusion)
What type of damage is caused by oxidative stress?
Oxidation of haem iron to form methaemoglobin and Heinz bodies
Heavy metals and certain foods can lead to oxidative damage.
Which heavy metals are particularly toxic to farm animals?
- Zinc
- Copper
Sheep are especially susceptible.
Name some foods that can cause oxidative damage in animals.
- Onions
- Leeks
- Garlic
- Rape
- Kale
- Cabbages
What is the main drug associated with oxidative damage in small animals?
Paracetamol (acetaminophen)
Cats are especially susceptible to paracetamol toxicity.
What is the treatment for paracetamol toxicity?
- N-acetylcysteine
- Methionine (if acetylcysteine is unavailable)
- Ascorbic Acid (for cats)
- Supportive care (Oxygen therapy, IVFT)
What type of bacteria is Ehrlichia?
Rickettsial bacteria
It is transmitted by ticks and infects macrophages and monocytes.
What are the clinical signs of Ehrlichia infection?
- Thrombocytopaenia
- Hyperglobulinaemia
- Depression
- Fever
- Weight loss
- Poor appetite
- Enlarged lymph nodes
- Epistaxis
- Petechiae
- Ecchymoses
What is the treatment for Ehrlichia infection?
- Doxycycline
- Imidocarb (unlicensed)
Both treatments are cheap and very effective.
Fill in the blank: The first step in managing a 3-year-old cat with pyrexia and anaemia is _______.
blood transfusion
True or False: Steroids should be given to treat IMHA secondary to an infectious cause.
False
Steroids can worsen the condition.
What is the significance of reticulocytes in anaemia?
They indicate bone marrow response to anaemia
Reticulocyte counts help assess regeneration in anaemia cases.
