serum proteins and dysproteinemias Flashcards
serum protein concentrations reflects balance between:
intake/production and losses
dilution/concentration
what are serum proteins used for?
structural protein
generate energy
site of synthese for plasma proteins
liver
immune system
small quantities of structural proteins and enzymes also present
impact of age on proteins: birth
globulins and albumin are low
immunological inexperience
high body water content
may see a transient spike in gobulins post-colostrum
impact of age on proteins: elderly
progressive increase in Ig
small decrease in albumin
refractometry
estimates protein
“line” refraction of light passing through materials with different densities
temperature dependent
measures total solids-includes “other” stuff
CBC total protein by refractometry is HIGHER than total protein on chem profile
dye binding methodology
serum protein measurement in wet chemistry analyzers based on dye binding
affected by dye and species
beware of human labs
electrophoresis
separates by migration in an electric field
rate of migration related to charge, size, electric field and media
immunoelectrophoresis can sort out different kinds of Ig but is rarely available
pre-albumin
most rapidly migrating fraction
most often seen in birds
known function in thyroxine binding and transport
albumin
only individual protein seen in electrophoresis
made in liver
transporter and storage pool
75% of plasma osmotic activity
binding prevents renal loss of plasma constituents
globulins
alpha-mostly lipoproteins and acute phase reactants, may increase with inflammation
beta-more acute phase reactants, some Igs
Gamma-mostly Igs
acute phase response
multiple inflammatory stimuli elicit
on activation, cells secrete proinflammatory cytokines
in liver, cytokines such as IL-6, IL-1 and TNF-alpha results in synthesis of acute phase proteins
interpretation
age-colostrum intake can markedly increase globulins
pregnanct-albumin may decrease, globulins may increase then decrease with colostrum production
nutrition-generally require marked starvation or combined with increased losses
selective hypoproteinemia
low albumin with normal or increased globulin
decreased liver function
increased selective loss-glomerular
nutritional-uncommon, must be severe
pan hypoproteinemia
low albumin and globulins
generally non-selective losses: hemorrhage, third space, burns, gastrointestinal
may be dilutional: physiologic-age/pregnancy, iatrogenic fluid overload, diseases (Heart failure)
