Fistula - Genetic Cause?

Im in a somewhat similar boat- my uncle (my moms brother) had one (abscess followed by fistula) in 2011 and i had one in 2014. Neither of us have Crohns or diabetes. The fact is that, although fistulas are proportional much more common in people with Crohns, most anal fistulas (90-95%) are not Crohns related. 

There is no known genetic component to the development of an anal fistula itself. However, there ARE genetic causes of conditions that, over long term or bad luck, can increase the chance of fistula.

Chronic straining on the toilet or constipation can occasionally cause fistulas, particularly on the long term if the straining is consistent over years. This can happen in two ways- the stool clogs the anal glands which lie just inside the anus (the most common cause, to the best of my knowledge) or the anus is torn (fissure) and this tear becomes infected and creates a fistula. The chance of a fistula developing from a fissure is around 1 in 50000 but if you consistently have fissures without remedying them this chance increases and lifestyle choices that impact the immune system (e.g. Smoking cigarettes) also increases the chance. Actually, cigarette smoking has been shown to have some correlation with perianal abscesses, probably due to its impact on the immune system. Lastly, holding in bowel movements for long periods also could have a factor on the long term. 

My best advice is to have the fistulotomy. Its the gold standard and, so long as you dont have Crohns, its unlikely to come back (90-98% success rate). People often worry about incontinence, but i never had any problem. The surgery was actually relatively painless. The hard part was keeping the area clean, since when i switched to a high fiber diet following the surgery i started pooping 3-4 times per day. But infection of the fistulotomy wound is very rare. 

Its unlikey to happen again, but its best to avoid constipation (this includes holding poops) at all times. I now take Metamucil every night and it works wonders. 

Hi Birdie, I had my first abscess 7 years ago. Then bang this summer I got a lovely perianal abscess. Had that drained and packed for weeks only for it not to heal and then it was discovered that I had a fistula. I'm 5 weeks post fistulotomy and healing great. But in the middle of all this I found out my dad suffered a lot when he was younger with abscesses and he had fistulas. No one else in my family has had them just myself and my dad. I'm really hoping that it's just bad luck and not genetic, as I really don't think I could deal with it all over again.