Pruritus ani is a condition typified by intense itch as well as anal pain, and itching doesn't appear to be your primary complaint. As such, I am a little skeptical of this diagnosis, at least as the principal one involved. Yes, you could suffer from pruritus ani (not uncommon), and hence you would find some relief from diet and other lifestyle modifications recommended to treat the disease. But I'm of the opinion that there may be something else involved here, as well.
I think making another appointment with a proctologist is definitely in order. Perhaps return to the one you already saw, if you were comfortable with him/her; but the lack of response to your email, and apparent lack of ideas for follow-up is not, in my opinion, a real confidence-inducer. If you agree, you might try and set up an appointment with another proctologist.
Hopefully, a second opinion will help here. I don't think seeing another generalist (e.g. internal medicine physician, etc.) is indicated, since I don't think that they'll have much to add. Another exam will probably take place, and they may decide to perform a colonscopy at some point. An external exam might not be providing enough information at this point (you didn't mention if any anoscopy was performed), and a colonscopy might be of some help.
Pruritus ani is itchy and painful, and can lead to irritation and bleeding, but it doesn't sound like, to me, that you ever experienced much itching. Yes it could be a component, but I am of the opinion that there is likely something else going on, another diagnosis.
One more thought - it sounds as if you are doing everything right, with the dietary modifications, vegetarian diet (I, myself, am vegan), and trying all of the different available over the counter preparations.
I hope this helps. Please let me know if you have any further questions - I'm more than happy to help. Take care.
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