Liphook Equine Hospital Laboratory Newsletter winter 2012/13
- Liphook now using ACTH > 39 pg/ml as indicating positive for PPID and < 19 pg/ml as indicating negative.
- In 206 paired ACTH samples (5 - 15 minutes apart) from horses suspected of having PPID, 5 horses had both positive and negative results. However, Liphook suggest that the TRH stimulation of ACTH is a better test than testing 2 baseline ACTH samples.
- Post-mortem evidence suggests that using ACTH as the sole test for PPID is likely to underdiagnose the condition - this agrees with findings in the USA that none of the currently available tests for PPID will pick up early histological signs of pituitary dysfunction.
- Liphook is finding the TRH stimulation of ACTH a useful test, and is now using 81 pg/ml (10 minutes after administration?) as the cut-off.