We have upgraded our Endocrinology Analysers and are proud to introduce the Immulite 2000 xpi System.
Our driving ethos at Liphook has always been to stay ahead of the game and offer the latest and best to all of our laboratory users. Thus, we have recently purchased two Siemens Immulite 2000 xpi analysers, the newest and most proficient chemiluminescent immunoassay system available in this format which supersedes the older Immulite 1000 system used by most other labs. These new analysers allow greater precision, accuracy and throughput and, given that we have duplicate machines, this means that we can guarantee uninterrupted output of results even in the unlikely event of a machine malfunction.
It is well recognised that different assays and analysers generally return different results, and even the change from Immulite 1000 to Immulite 2000 xpi is no different in this respect. We have spent the past 6 months validating the new analysers and re-establishing appropriate cutoffs for diagnostic use and so you will see slight differences on forthcoming laboratory reports.
We apologise as I’m sure we’d all prefer to stay with our previous familiar values, but this change not only improves test reliability, but will in time be inevitable as the old Immulite 1000 system is withdrawn. We felt that as reference intervals (for ACTH at least) are about to change with the season in any case, this was the best time to implement this change. Should you require any assistance with interpretation or comparison with previous results then don’t hesitate to contact us to discuss.
Effects on ACTH reporting
As a general guideline the newly generated ACTH values will be slightly lower than previously (by around -10%) meaning lower cutoffs. In general terms this means a cutoff between 23-26 pg/mL for most of the year, rising slowly from July to a peak of 50 pg/mL in late September and returning to baseline by mid-November. Liphook Equine hospital remains the only laboratory internationally with valid ACTH reference ranges available for every week of the year, allowing greater accuracy of interpretation.
Effects on Insulin reporting
As a general guideline the newly generated insulin values will be higher than previously (by around +30%) meaning higher cutoffs. Resting insulin values in normal horses are expected to be no higher than 30-50 mU/L depending on the diet, and the response to 0.45 mL/kg Karo Light Corn Syrup should be no higher than 63 mU/L between 60-90 mins post-dosing.