A fluorescent artefact resembling BB-creatine kinase in sera of patients with prostatic disease

A fluorescent zone with mobility towards the anode almost equal to that of human BB-creatine kinase has been detected after electrophoresis on cellulose acetate of sera from each of 28 patients with prostatic carcinoma. The zone is not due to the BB isoenzyme and its appearance does not depend on the presence of substrates of creatine kinase. It therefore appears to be a further example of a fluorescent artefact resembling a creatine kinase ieoenzyme. These observations indicate a need for caution in assessing the possible value of BB-creatine kinase in patients with prostatic disease.