Changes

==Causes of Hypoalbuminaemia==

==Causes of Hypoalbuminaemia==

The synthesis of albumin may be reduced or it may be lost in greater quantities than normal:

The synthesis of albumin may be reduced or it may be lost in greater quantities than normal:

*Reduced synthesis of albumin

 

**'''Severe malnutrition''' resulting in the inability to synthesise sufficient albumin, also known as '''protein energy malnutrition'''.

'''Reduced synthesis of albumin'''

**Elaboration of an '''acute phase response''', in which the production of positive acute phase proteins (such as globulins and c reactive protein) is favoured at the expense of negative acute phase proteins like albumin and transferrin.  Globulins will be elevated in this response, with a reduced albumin: globulin ratio.

*'''Severe malnutrition''' resulting in the inability to synthesise sufficient albumin, also known as '''protein energy malnutrition'''.

**'''Severe hepatic insufficiency''', as in chronic liver failure or with congenital porto-systemic shunts.

*Elaboration of an '''acute phase response''', in which the production of positive acute phase proteins (such as globulins and c reactive protein) is favoured at the expense of negative acute phase proteins like albumin and transferrin.  Globulins will be elevated in this response, with a reduced albumin: globulin ratio.

*Increased loss of albumin

*'''Severe hepatic insufficiency''', as in chronic liver failure or with congenital porto-systemic shunts.

**'''Severe exudates''' that contain large quantities of protein may deplete the plasma proteins:

 

***'''Dermal protein loss''' after severe thermal or chemical burns.

'''Increased loss of albumin'''

***'''Septic peritonitis''' involving copious amounts of exudative peritoneal fluid.

*'''Severe exudates''' that contain large quantities of protein may deplete the plasma proteins:

**[[Protein Losing Enteropathy|'''Protein-losing enteropathy''']] (PLE) caused by [[Inflammatory Bowel Disease|inflammatory bowel disease]], [[Lymphangiectasia|lymphangiectasia]] or [[Lymphoma|alimentary lymphoma]].  Globulins and, in severe cases, whole blood are lost with albumin in this condition.

**'''Dermal protein loss''' after severe thermal or chemical burns.

**'''Protein-losing nephropathy''' (PLN) caused by primary glomerulopathy, glomerulonephritis or amyloidosis.  Albumin, having a smaller molecular weight, is lost in great excess of globulin.  Severe PLN results in Nephrotic Syndrome characterised by severe hypoproteinaemia, hypercholesterolaemia, ascites, hydrothorax and subcutaneous oedema.

**'''Septic peritonitis''' involving copious amounts of exudative peritoneal fluid.

**'''Acute haemorrhage''' followed by autotransfusion (movement of fluid into the circulation from the interstitium) will result in dilution of the remaining plasma proteins.

*[[Protein Losing Enteropathy|'''Protein-losing enteropathy''']] (PLE) caused by [[Inflammatory Bowel Disease|inflammatory bowel disease]], [[Lymphangiectasia|lymphangiectasia]] or [[Lymphoma|alimentary lymphoma]].  Globulins and, in severe cases, whole blood are lost with albumin in this condition.

*Apparent hypoalbuminaemia may occur in '''overhydrated or hypervolaemic animals''' suffering from primary (pyschogenic) polydipsia or which have received intra-venous fluid therapy.

*'''Protein-losing nephropathy''' (PLN) caused by primary glomerulopathy, glomerulonephritis or amyloidosis.  Albumin, having a smaller molecular weight, is lost in great excess of globulin.  Severe PLN results in Nephrotic Syndrome characterised by severe hypoproteinaemia, hypercholesterolaemia, ascites, hydrothorax and subcutaneous oedema.

*'''Acute haemorrhage''' followed by autotransfusion (movement of fluid into the circulation from the interstitium) will result in dilution of the remaining plasma proteins.

 

 

Apparent hypoalbuminaemia may occur in '''overhydrated or hypervolaemic animals''' suffering from primary (psychogenic) polydipsia or which have received intra-venous fluid therapy.

==Consequences of Hypoalbuminaemia==

==Consequences of Hypoalbuminaemia==

Albumin is the major plasma protein contributing to the maintenance of plasma oncotic pressure (also known as colloid osmotic pressure).  This force opposes hydrostatic pressure and prevents the loss of intravascular fluid into body cavities and the interstitial space.  Hypoalbuminaemia may therefore lead to the following conditions when the concentration of albumin falls below 10-15 g/l:

Albumin is the major plasma protein contributing to the maintenance of plasma oncotic pressure (also known as colloid osmotic pressure).  This force opposes hydrostatic pressure and prevents the loss of intravascular fluid into body cavities and the interstitial space.  Hypoalbuminaemia may therefore lead to the following conditions when the concentration of albumin falls below 10-15 g/l:

*'''Ascites''' and '''hydrothorax''' composed of transudate fluid.

*'''Ascites''' and '''hydrothorax''' composed of transudate fluid.

==Diagnosis==

==Diagnosis==

Total serum protein concentration can be estimated by refractometry but this technique does not differentiate albumin from the plasma globulins.  This is important because, in some chronic inflammatory liver diseases, albumin may be reduced by hepatic insufficiency while total protein concentration may remain normal due to the production of globulins in the inflammatory process.

Total serum protein concentration can be estimated by refractometry but this technique does not differentiate albumin from the plasma globulins.  This is important because, in some chronic inflammatory liver diseases, albumin may be reduced by hepatic insufficiency while total protein concentration may remain normal due to the production of globulins in the inflammatory process.