Thinking caps for a feline medical mystery ...

A small AstroMystery ....

When I got home from vacation, I noticed that Astrophe's eyes had changed. (She had been started on cyclosporin 10 days prior to this, due to a relapse in her IMHA.) At the 6 o'clock position on each iris, directly below the pupil, was a large area of extra pigment. It was not a pool of liquid (altho' the positioning made it look like the colour had drained from her eye and pooled at the bottom!) It was pretty similar to her own eye colour (coppery), but more intense. I pointed it out to Dr R, who wondered if I had perhaps just not noticed it before. Uh ... no.

Add to that, extremely miotic (constricted) pupils. Almost pinprick pupils. Even the vet noticed that- was quite noticeable. (Astrophe usually has adrenalin-dilated pupils at the vet, not constricted!)

Within a few days of taking her off the cyclosporin (not just for this, but also because it gave her pancreatitis), the iris pigment began to return to normal, as did the pupils.

I can't find any literature that connects iris/pupil changes to cyclosporin. Or anything else, for that matter!

Anyone ever see this? Any ideas?

 

I found this as a listed side effect of cyclo...

Ocular

A rare manifestation of neurotoxicity induced by cyclosporine (which has occurred in transplant patients more frequently than in other indications) is optic disc edema including papilledema, with possible visual impairment, secondary to benign intracranial hypertension.

Ocular side effects have included reports of pseudotumor cerebri, which resolved rapidly upon discontinuation of cyclosporine, and optic disk edema. Permanent blindness has been reported in one patient. A case of cyclosporine-induced retinal toxic blindness has also been reported.

Read more: http://www.drugs.com/sfx/cyclosporine-s ... z0oCeq8jAx

 

Thanks, Sheryl. I saw that when I was researching, and it scared me at first, but it don't that's it. Pseudotumour affects cranial pressure (terrible headaches), and internal eye pressure, etc., but shouldn't affect the iris pigmentation. And I think that the pupils usually dilate with it, not constrict.

But thanks for playing! :lol:

 

Hi Karen

Miosis and iris pigment changes could both be from uveitis, you can ask your vet about this possibility since she saw the changes herself. It could be more related to a potential underlying condition than the cyclosporine -- that may have been coincidental. I'm not sure if cyclosporine, as an immune suppressant, could allow something to flare up within the eye? rather than it being the cause of it, if that makes sense. I think it's more likely than as a side effect of the cyclosporine. I'll poke around and let you know if I find anything out.

 

Thanks, Jess. I had considered uveitis and iritis, but couldn't figure out how to test for them in a cat! LOL! There was no tearing, no third eyelid, no redness of the conj, etc. The iris pigmentation was not diffuse and was oddly symmetrical. She was not pawing at the eyes.

The extra pigment faded equally and is now gone.

I even considered bilateral Horners, but that didn't fit either.

Looking forward to seeing what you dig up. Thanks!!!

 

It seems that those symptoms can be caused by cyclosporin drops (0.1%) applied directly to the eye:

http://www.ncbi.nlm.nih.gov/pubmed/9594542

So maybe her symptoms were some sort of toxicity to the cyclosporin?

FYI Restasis is 0.05%, but it still makes you wonder about it.