If you have a temp ileostomy, it can be perfectly normal to pass stool via your rectum and anus. This is because with a loop ileostomy, there are two stoma openings, one (the mucous fistula) that connects to your anus and the other (the 'working' stoma) that connects to your upper digestive tract.
Both stomas are housed in the same bag and sometimes stool can go from the bag into the mucous fistula and out via anus and rectum. It's something the surgeon often forgets to warn people can happen and consequently, the patient can panic when they feel that nothing should be coming out their back end. Often, it can just be mucous that's coming out (it can sometimes be pasty like stool though) which, again, is perfectly normal.
If your op was recent, I would expect old blood to be present as a remnant from your op and should stop soon (old blood is usually a darker brown, fresh blood is a brighter red. If it's fresh blood, it is probably an idea to see your doc to find out what's going on there, I wouldn't panic about it though).
As with anything, if you are worried, seek medical advise, if only to put your mind at ease.
I have had an ileostomy for 32 years now due to UC.
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