[Determination of protein in cerebrospinal fluid: comparison of the Coomassie-Blue method and the Cu-Folin differential test].

Comparison of within-run and between-day imprecision of protein assays using CSF controls as well as 96 random CSF samples from the routine laboratory shows that the Cu-Folin differential test and the Coomassie-Brilliant-Blue method from Bio-Rad are equally suited to total protein determination in cerebrospinal fluid. Problems possibly arising with very low concentrations of CSF or urine protein and the influence of some drugs often used in the neurological clinic are presented and discussed.