Changes

* Haemolytic anaemias often result in a degree of hyperbilirubinaemia which, if sufficiently severe, will be evident as icterus. RBC destruction leads to an increased level of unconjugated bilirubin which exceeds the rate of hepatic excretion. Acute severe anaemia may also cause hypoxic or toxic hepatic injury, resulting in decreased bilirubin metabolism and cholestasis. Although hyperbilirubinaemia results primarily from increased unconjugated bilirubin, conjugated bilirubin also increases and leads to bilirubinuria. Evaluation of unconjugated versus conjugated bilirubin is often not helpful when trying to differentiate between pre-hepatic and hepatic jaundice.

* Haemolytic anaemias often result in a degree of hyperbilirubinaemia which, if sufficiently severe, will be evident as icterus. RBC destruction leads to an increased level of unconjugated bilirubin which exceeds the rate of hepatic excretion. Acute severe anaemia may also cause hypoxic or toxic hepatic injury, resulting in decreased bilirubin metabolism and cholestasis. Although hyperbilirubinaemia results primarily from increased unconjugated bilirubin, conjugated bilirubin also increases and leads to bilirubinuria. Evaluation of unconjugated versus conjugated bilirubin is often not helpful when trying to differentiate between pre-hepatic and hepatic jaundice.

References: [[NationWide Laboratories]]  

Haemolysis References: [[NationWide Laboratories]]  

Haemolysis may occur in the following processes:

Haemolysis may occur in the following processes:

*'''Hypophosphataemia''' which occurs in post-parturient cattle (causing post-parturient haemoglobinuria), with refeeding syndrome and when animals with [[Diabetes Mellitus|diabetes mellitus]] are stabilised with insulin.

*'''Hypophosphataemia''' which occurs in post-parturient cattle (causing post-parturient haemoglobinuria), with refeeding syndrome and when animals with [[Diabetes Mellitus|diabetes mellitus]] are stabilised with insulin.

*Exposure to '''toxins''' including rape and kale (which contain SMCO radicals) in cattle, onions and garlic in dogs and paracetamol in cats.

*Exposure to '''toxins''' including rape and kale (which contain SMCO radicals) in cattle, onions and garlic in dogs and paracetamol in cats.

*'''Microangiopathic anaemia''' which occurs when red blood cells are forced through small meshworks of fibrin as with [[Haemangiosarcoma|haemangiosarcomas]], [[Disseminated Intravascular Coagulation|disseminated intravascular coagulation]] (DIC) or bacterial endocarditis.This is usually a mild, often subclinical anaemia unless there is concurrent haemorrhage from, for example, a tumour. RBCs are damaged as they pass through abnormal vessels or regions of turbulent blood flow, giving rise to schistocytes. These fragmented red cells are phagocytosed by the mononuclear phagocytic system, causing anaemia. Numerous schistocytes in a smear are always significant. References: [[NationWide Laboratories]]

*'''Microangiopathic anaemia''' which occurs when red blood cells are forced through small meshworks of fibrin as with [[Haemangiosarcoma|haemangiosarcomas]], [[Disseminated Intravascular Coagulation|disseminated intravascular coagulation]] (DIC) or bacterial endocarditis.

This is usually a mild, often subclinical anaemia unless there is concurrent haemorrhage from, for example, a tumour. RBCs are damaged as they pass through abnormal vessels or regions of turbulent blood flow, giving rise to schistocytes. These fragmented red cells are phagocytosed by the mononuclear phagocytic system, causing anaemia. Numerous schistocytes in a smear are always significant. References: [[NationWide Laboratories]]

Haemolysis usually results in a more strongly regenerative response than haemorrhage and can be differentiated by plasma protein concentrations; these will fall with haemorrhage, but not with haemolysis.

Haemolysis usually results in a more strongly regenerative response than haemorrhage and can be differentiated by plasma protein concentrations; these will fall with haemorrhage, but not with haemolysis.

'''Proliferative disorders.''' Can also cause nonregenerative anaemia as neoplastic cells over-run the bone marrow (myelophthisic disease).

'''Proliferative disorders.''' Can also cause nonregenerative anaemia as neoplastic cells over-run the bone marrow (myelophthisic disease).

References: [[NationWide Laboratories]]

Primary Anaemia References: [[NationWide Laboratories]]

'''[[Immune Mediated Haemolytic Anaemia|Pure red cell aplasia]]'''

'''[[Immune Mediated Haemolytic Anaemia|Pure red cell aplasia]]'''

'''FIV.''' May be associated with nonregenerative anaemia possibly with concurrent neutropaenia.

'''FIV.''' May be associated with nonregenerative anaemia possibly with concurrent neutropaenia.

References: [[NationWide Laboratories]]

Infections References: [[NationWide Laboratories]]

=== Secondary Anaemia ===

=== Secondary Anaemia ===

'''Hypothyroidism and hyperadrenocorticism.''' These endocrinopathies may result in mild, clinically insignificant anaemia.

'''Hypothyroidism and hyperadrenocorticism.''' These endocrinopathies may result in mild, clinically insignificant anaemia.

References: [[NationWide Laboratories]]  

Secondary Anaemia References: [[NationWide Laboratories]]  

=== Iron Deficiency Anaemia ===

=== Iron Deficiency Anaemia ===