Albumin, synthetised primarily by the liver, represents 50 to 60% of total serum proteins. Because of its small size and its high plasmatic concentration, albumin is the major protein component of most extravascular body fluid, including CSF, interstitial fluid, urine
and amniotic fluid. Albumin’s primary function is the maintenance of colloidal osmotic pressure in both extravascular and vascular
spaces, with continuous equilibration. Albumin also binds and transports a large number of compounds (ions, free fatty acids, bilirubin, drugs…). Albumin is a mobile reserve of amino acids.
Increased levels of albumin are present only in acute dehydratation, especially critical for newborn. Hypoalbuminemia is seen in a
multitude of diseases bound to different pathological states: 1) acute and chronic inflammation, 2) decreased synthesis: hepatic insufficiency, malnutrition, analbuminemia, 3) increased loss : nephritic syndrom, gastrointestinal loss, sever and large burns, bedsore,
4) increased catabolism : fever, hyperthyroidism…