Seeking Input: What Tests Should I Ask For?

[Kirikou]

I’m looking for advice from all “armchair vets” about my 22-year-old retired OTTB gelding. He’s had an ongoing series of health issues for the past year, that we’ve been addressing as they come up, but I’m trying to figure out the bigger picture. Here’s the backstory:

1. Initial Issue: A year ago, he developed what appeared to be a single, hard, egg-sized lump near his retropharyngeal lymph node. No fever or symptoms. Vet suspected a benign growth common in older horses and said to just keep an eye on it.
2. Spring Allergies: About five months later, he had a cough and clear nasal discharge. Vet treated with Dex, and while the nasal discharge stopped, the cough persisted.
3. Leg Issues: A month later, he developed what looked like scratches on a white hind leg. Treated with our usual remedies which didn’t work - called the vet but when the vet applied his preparation, the leg became hot, swollen, and non-weight bearing. Swelling resolved within 24 hours with cold hosing/icing, but the leg has since had periodic flare-ups that always resolve quickly.
4. Full Workup: Late summer, I asked for a comprehensive exam due to the “not quite right” picture:

• Crackly lungs, tachypnea, no fever.
• Bloodwork: Elevated WBC values prompted a second round sent to Cornell. Nothing glaring except a low T4 (0.56).
• Vet prescribed levothyroxine, saying the mass near the throatlatch was probably a thyroid mass then. (Now, I myself am hypothyroid, and he doesn’t show the typical symptoms I’d expect, like lethargy or sluggishness. He’s always been an energetic, typical hard-keeping TB.).

Current Status:

• Mass near the throatlatch is still there.
• No cough since the fall.
• Bright, happy, good appetite, shiny coat, but has lost weight on levothyroxine (likely not helped by winter/polar vortex).
• Leg still occasionally flares up.

Questions:

• Should I continue treating with levothyroxine?
• Are there additional tests I should request?
• What could explain the combination of symptoms?
• Any ideas for managing this locally? (We’re rural, with only a general large-animal farm vet nearby. The nearest equine hospital is a 7-hour round trip, and pony is not a great traveler - like not at all…)

Thank you in advance for any advice or insights!

[Simkie]

I’d be awfully tempted to ask about biopsying that lump. Not sure if you’re looking at a straight forward fine needle aspirate or if you’d need ultrasound guidance? But since you feel that kicked off all this, it’s not unreasonable to take a look at what it actually is.

[Kirikou]

@Simkie

I’d be awfully tempted to ask about biopsying that lump. Not sure if you’re looking at a straight forward fine needle aspirate or if you’d need ultrasound guidance? But since you feel that kicked off all this, it’s not unreasonable to take a look at what it actually is.

Thanks, @Simkie! I asked about a biopsy when the lump first appeared, but the vet wasn’t comfortable doing it at that point and said it would require ultrasound guidance given its location. I’m still really curious about what it is, though, so I may bring it up again and see if it’s worth revisiting now. Appreciate the suggestion!

[JB]

The lump is most likely a benign adenoma,especially if it’s movable and you can push it in. My TB mare developed one a few years ago when she was 19/20, and now has another one. My vet has felt them both, and isn’t concerned at all, stating what yours did - they’re relatively common in older horses and aren’t a problem. Obviously keep an eye on it, and if it gets painful, or grows large, then maybe time to biopsy

At his age, with some of these issues, I’d test for PPID.

How lot was his T4? Is there by chance any previous baseline?

If it were ME, I’d wean off the levo, then test for PPID. From now until end of June you ideally want the TRH Stim test. If you do the ACTH test, you could get a false negative

[Simkie]

That’s a bummer. Does your local vet have the ability to scope? Taking a look at the gutteral pouches etc might tell you something.

Any chance there’s a specialist vet who travels into your area? I was able to use a boarded internist from a couple states away when I had a weird case once. She came to my farm. If you share your general area, people here might have some ideas for you along those lines?

[NaturallyHappy]

This suggestion won’t solve your problem, but we had one w a lump in a similar area. Our vet did want to biopsy (he’s a surgeon) but the owner didn’t. It was rather firm. Another vet thought it might be an infected salivary gland and recommended leaving it alone w Icthamol on it. It eventually burst- just a tiny bit of drainage - and now you can’t even tell where it was. Good luck…I hope you get to the bottom of this. Your pony has been checked for PPID??

[NaturallyHappy]

I think the three of us posted at the same time😀

[Kirikou]

@Simkie

Any chance there’s a specialist vet who travels into your area? I was able to use a boarded internist from a couple states away when I had a weird case once. She came to my farm. If you share your general area, people here might have some ideas for you along those lines?

That’s a great idea! My dentist travels too and comes from out of state, I should ask her if she knows of anyone.
I’m in rural Iowa, so if anyone here has recommendations for a traveling specialist in the area, I’d love to hear them. Thanks so much for the suggestion!

[Kirikou]

@JB

At his age, with some of these issues, I’d test for PPID.

How lot was his T4? Is there by chance any previous baseline?

Thanks for this @JB ! We’ve actually done a couple of ACTH tests over the past three years, and both came back “within range,” but I’ll definitely ask about the TRH Stim test—appreciate the tip about timing it!
His T4 was at 0.56, but unfortunately we don’t have any previous baseline to compare it to as that was the first time we tested for that.
It’s also reassuring to hear about your mare’s benign adenomas—thank you for sharing that!

[Kirikou]

@NaturallyHappy

This suggestion won’t solve your problem, but we had one w a lump in a similar area. Our vet did want to biopsy (he’s a surgeon) but the owner didn’t. It was rather firm. Another vet thought it might be an infected salivary gland and recommended leaving it alone w Icthamol on it. It eventually burst- just a tiny bit of drainage - and now you can’t even tell where it was. Good luck…I hope you get to the bottom of this. Your pony has been checked for PPID??

Thanks for sharing your experience @NaturallyHappy! I have some Ichthammol in the tack room, so I’ll give that a go—can’t hurt to try!
And yes, we’ve tested for PPID in the past, including the most recent bloodwork we sent to Cornell, but it was the ACTH test. I’m now thinking we should follow up with the TRH Stimulation test @JB mentioned, especially since it sounds like the ACTH might not always give the full picture. I will have to check with the local vet on whether he can/is willing to do that. Thanks again for the suggestion and the good wishes!

[JB]

@Kirikou

We’ve actually done a couple of ACTH tests over the past three years, and both came back “within range,”

Do you know what dates, and what the numbers were?

[Kirikou]

@JB

Do you know what dates, and what the numbers were?

I’ll have to go back in my record book for the actual numbers when I get home tonight. One was in the Spring and the latest one was (unfortunately as I understand it’s not ideal) in late September.

[JB]

Late September is excellent for the ACTH test. That’s the peak of the seasonal rise, and many early PPID horses will spike higher than the seasonal rise allows for. So if that was normal, then the odds are low that was a false negative. But, knowing the number will be helpful too.

For the Spring, it’s helpful to know if it was more middle to low normal, or high normal.

[NaturallyHappy]

@Kirikou

Thanks for sharing your experience @NaturallyHappy! I have some Ichthammol in the tack room, so I’ll give that a go—can’t hurt to try!

I clipped the area first. It was messy (of course) and took a couple of weeks to work. My grandparents were from IA💗.

[Simkie]

@Kirikou

My dentist travels too and comes from out of state, I should ask her if she knows of anyone.

Dr Julie Parks? I loooooooved her when we lived in Minnesota!! Miss her a ton. I hope she has some ideas for you (if that’s who you’re talking about, anyway!)

[kaya842]

Put me on the PPID bandwagon. I would also hazard a guess the lump and leg issues are unrelated (but the NQR, sickly ish makes me think PPID). I also agree a biopsy should be relatively straightforward and may provide some peace or at least more info.

[luvmyhackney]

Ask your vet about this program for testing? It covers the costs for at least 1 year.

https://idppid.com/testing-program

[Kirikou]

@JB

Late September is excellent for the ACTH test. That’s the peak of the seasonal rise, and many early PPID horses will spike higher than the seasonal rise allows for. So if that was normal, then the odds are low that was a false negative. But, knowing the number will be helpful too.

For the Spring, it’s helpful to know if it was more middle to low normal, or high normal.

Thanks so much for this—super helpful to know about the timing, @JB ! I checked my record book last night, and his ACTH was 29.7 in September and 12.6 in March of the previous year. I’m unsure if the increase is just seasonal? But I’ll chat with my vet about possibly resting or testing differently to determine if he might be borderline or in the early stages of PPID.

I really appreciate everyone who took the time to respond. If you have any other ideas or suggestions, please keep them coming—thank you all again!

[Kirikou]

@Simkie

Dr Julie Parks

Dr Parks is amazing! But unfortunately I don’t believe she still travels for dental work. Last I heard she was in practice in the Twin Cities area (which is a bit of a trek for me).

[Kirikou]

@luvmyhackney

Ask your vet about this program for testing? It covers the costs for at least 1 year.

This is SO helpful, thank you! Will be sure to mention it to the vet!