Hi Lesley.  I reviewed your CH- but its not current, so I apologize for the additional questions: 
1. 9-12-22 you tested ACTH levels- this is part of the seasonal rise time frame- Did Sophie have symptoms of PPID?  Why were you testing ACTH?
2. 10-18-2022- You did a full panel of bloodwork- but the insulin was still pending- do you have an insulin result for that date?
3. Pergolide was started 9/14/22  and her retest was down to 44.  What were the reference parameters? I don't see that bloodwork uploaded or added to your Case history. 

If you  are wanting the pergolide to be altering the ACTH to be therapuetic- we like to see horse be high teens to low 20's year round. ( That is when they definitely are diagnosed with PPID). Testing during the seasonal rise, can skew the diagnosis. 
Retesting in the spring with the TRH test seems reasonable. Keep Sophie on the pergolide till seasonal rise is over- would be my "safety net" if she were my horse. Here's some info on the TRH test. 

The Thyroid-Releasing (TRH) Stimulation Test: Thyroid releasing hormone (TRH) stimulates release of ACTH. In normal horses the rise is very small but in PPID horses it is pronounced. Samples for ACTH are drawn before and 10 minutes after TRH injection. This test has more false positives than endogenous ACTH but because of its higher sensitivity is a good test for horses strongly suspected to be early PPID horses but which test negative by endogenous ACTH. Results are not reliable during the fall seasonal rise.

When able, it would be super helpful to update your CH. If you could also add a comment of your current situation to the comment section that would help the next volunteer who answers your questions. Thanks! 

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Trisha DePietro
Aug 2018
NH
Primary Responder
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