Figure 1.
Measurement of oxalate concentrations in plasma versus serum. Oxalate concentrations were measured in plasma (POx) and serum (SOx). For each patient, an EDTA tube and a serum tube were drawn at the same time, immediately put on ice and processed. (a) SOx concentrations tend to be slightly higher than POx concentrations (n = 10, P = 0.10, mean coefficient of variation 0.10). The red line indicates the mean values of all POx/SOx concentrations. (b) SOx/POx ratio depending on the POx concentration.