Does anyone here have or suspect having an autoimmune disease causing the fissure and if yes, what are the symptoms ?

Hello PinkSparkle,
The only information that I have on fissures and autoimmune disease is the position of the fissure. Most fissures are in the anterior position (90%, both men and women), while fissures in any other position can mean an autoimmune disease is the cause, but there are other reasons. I have an autoimmune disease but was told it had nothing to do with the fissure in this case.
This is a good link, and it has information about the position of the fissure on the first http://www.medicinenet.com/anal_fissure/article.htm

Thank you for answering. That link is very useful.
I have read before about the location and found this picture which makes it quite clear.

I was afraid of an autoimmune because I had about 3 or 4 fissures until now (but they came after hard stools) and some abdominal pain (it seems to be gone at the moment). I'm the kind of person that freaks out when hearing about diseases and I find hard controlling these feelings. I have read on the Internet that autoimmunes give more persistent and annoying reactions than what I have been experiencing, so I'm trying to calm down. The doctor I went to see said I wait a little longer before worrying because it takes time to heal fissures...(plus the method of finding out would be a colonoscopy which, again, scares me as hell).
How have you found out what your condition was? Were the symptoms "yelling" it was something serious?I would really appreciate if you answer that, I don't have any friends suffering from an autoimmune condition to ask

Great pic, PSparkle!
Don't worry, we have all freaked out on this wretched voyage of the Anal Fissure (had this for over two years now).
I would not worry about an autoimmune disease unless you have been diagnosed with one, or you have something else going on that you think is more than the fissures. I have Behcet's Disease, but it has nothing to do with the fissures. A bit difficult for me to go into the inns and outs of it, but you can have a look on the web. I don't have the most serious variety, and don't take strong drugs for it. It did not scream out - had a few symptoms for years and years and did nothing until I got quite ill with mouth ulcers.
I have not had a colonoscopy (don't want to), and CRS are pretty loathe to give younger people like yourself these unless they think cannot find an answer, hence why your doctor possibly wants to do that. (Is this a colon and rectal surgeon, by the way.) I have, however, had a sigmoidoscopy and an anoscopy. Anoscopy hurt like hell, but for the sigmoidoscopy I had a sedative and it was done in hospital. All they came back with was diverticulosis, hemorrhoids and healing fissure. Have also had an MRI and a CT scan.
Abdominal pain is not a common feature of fissures, but could be diverticulosis, as I get this if there is a flare-up from me eating something that irritates. I watch my diet carefully...very boring, but necessary.
Hope this helps a bit. Sorry you are going through all this

Here most doctors tend to recommend colonoscopy just to see if there is something else wrong, sometimes even to patients that present to the doctor with only one symptom.
I decided to wait some more time as I have adjusted my lifestyle (again) and if I see no improvement I will definitely go see another doctor. I had an anuscopy and it didn't hurt (just uncomfortable) but I read it is not good to have them too often as might make the fissure worse. Don't know if this is for real, but I'm really tired of seeing doctors and I hope I will do better this time.
I sometimes fear an autoimmune because I had one fissure that healed and then another one and so on. This is the 3rd or 4 th time.Although I have made major changes in my diet, the fissures came after making little mistakes such as wipe, not drinking enough water and eating enough fiber for 1 or 2 days, so...maybe it's just me and not an autoimmune...
Don't want the colonoscopy either, I'm so scared! :( (unfortunately I am the kind of person that freaks out only when hearing about a disease ).
Can you please tell me what age were you when your symptoms started?
For the hemorrhoids you could use a special pillow. I don't have hemorrhoids but I have been using one for another purpose but it also kept me from sitting on my fissure. I have described it and talk about it on the user TLTOSU 's thread in the "new to the forum " section. You probably did the proper research and already know about it, but anyway please take a look, I think it might help).
Good luck!