Can PTHrP be measured in serum or do I really need to submit plasma?
Plasma is preferred for PTHrP measurement. In a study that did here at MSU, we looked at PTHrP concentrations in paired plasma and serum samples. PTHrP was negative in about 50% of the serum samples when the plasma sample showed an elevated concentration of PTHrP. Thus, false negative results are obtained with serum, most likely due to the degradation of PTHrP.
