Plasma proteins diagnostic tests

Iopanoic acid is as potent a uricosuric agent as probenecid and this effect might explain some renal complications aspirin reduces the uricosuric effect but can also impair X-ray visualization because of competition at plasma protein-binding sites. Fluctuations of serum urate after oral cholecystography can interfere with diagnostic tests and even precipitate an attack of gout (578). 

Plasma proteins. Oestrogens cause an increase in proteins, particularly the globulins that bind hydrocortisone, thyroxine and iron. As a result, the total plasma concentration of the boimd substances is increased, though the concentration of free and active substance remains normal. This can be misleading in diagnostic tests, e.g. of thyroid function. This effect on plasma proteins passes off about 6 weeks after cessation of the oestrogen. 

The first tumor marker reported was the Bence Jones protein. Since its discovery in 1847 by precipitation of a protein in acidified boiled urine, the measurement of Bence Jones protein has been a diagnostic test for multiple myeloma (a tumor of plasma cells). More than 100 years after its discovery, the Nobel Prize-winning studies of Porter... 

Hamolsky, M. W., A. Golodetz, and A. S. Freedberg. 1959. The plasma protein-thyroid hormone complex in man. IB. Further studies on the use of the in vitro red blood cell uptake of Ij3j triiodothyronine as a diagnostic test of thyroid function. Journal of Clinical Endrocrinology and Metabolism 19 101-116. 

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