Dr. Agar Stuart Mott wanted me to share this with you


I have a dark circle on my fistula arm that started as an itchy rash two years ago. The area is now a “dead zone.” I can’t cannulate in that area. I have flares where it the circle becomes itchy, raised and red and then stops. I have pictures but I can’t figure out how to attach them to this post.


Dear Michelle

That is an impossible one to even come close to an answer without seeing, touching, scrapings for culture - particularly fungal cultures with microscopy for fungal hyphae or spores - and possibly (even likely) a biopsy … etc etc etc.

Sending a picture wont help much, nor is it likely to get you closer to the diagnosis - or its’ treatment.

Have you discussed this with your nephrologist, or a primary care physician? If they haven’t provided a satisfactory answer, then have you seen a dermatologist? Has it been biopsied? What treatments have already been tried?

This is not a question that can be answered over the Internet. It needs vision, hands on, and possibly a tissue diagnosis. At first reading, it does not sound like an issue primarily with the fistula, but with the skin - the dermis. It might be an area of chronic inflammation overlying, for example, a superficial tributary vein venous thrombosis, but that is for a hands-on doctor to assess. There are so many options in diagnosis here, most of which are unlikely to be directly related to the fistula.

I would suggest that you get it seen to … and stop casting wildly about on the Internet for advice. It won’t be productive. A dermatologist would be a good place to start.


Dr. Agar,

It has been seen by several doctors and biopsied. They are not sure what it is. I only posted it on this site because Stuart Mott asked me to bring it to your attention. I won’t be doing that again. Sorry to bother you.



Michelle, I wonder if https://www.crowdmed.com could help you? They do have a free version. You can post your history and the photos, and doctors and other clinicians and laypeople from around the world can weigh in. They may suggest tests that you haven’t had yet and would need to see a dermatologist for (I know it can take forever to get in to see one). Since your biopsies haven’t yet sorted out what this is, it might be helpful.


Thanks Dori, i have never seen anything like this before and I thought Dr Ajar might know