A recent request for CKMB revealed a total CK of 778 IU/L and a CKMB of 1449 IU/L (both were measured using Roche reagents). Other tests and controls in the batch did not reveal any such anomalies. I have a vague recollection of this sort of effect possibly being caused by binding of the enzyme to an immunoglobulin. Any other ideas? Dr D G Williams FRCPath ---------------------------------------------------------- This message was sent using http://uk2.net NEWS - CHEAPEST DEDICATED SERVERS IN THE WORLD - 29/month UK's FREE Domains, FREE Dialup, FREE Webdesign, FREE email %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%