Hi Anna all,
I just found your post, and thought I should write. About 10 years ago, I discovered a little white bump under the stoma, and it was quite painful. I gave it some time, but it didn't heal, and I learned to adjust the fitting of my flange, so it didn't irritate it. I didn't really have an "ostomy" doctor, but when I mentioned it to my gastro, he wanted to see it, but didn't know what it was, and thought I should see a surgeon. That thought freaked me out, and I just let "well enough alone". Hmmmm It stayed the way it was...sometimes more irritating than others, but didn't cause a problem.
A few years later, I was visiting a friend, got up early to use the bathroom, and emptied a pouch full of blood into the bowl. Scary. I took off my appliance, and blood started spouting all over her all white bathroom. I covered the stoma, and staunched the blood flow (which was coming from where that white "pimple" had been). I called the doctor and he had me rushed to the hospital.... No real diagnosis that day, but they cauterized the area, sent me home, and then it happened again the second day. Back to the hospital I went. This time, I was seen by a surgeon's team...but not the doctor himself. Was cauterized again....and made an appointment to see the doctor.
Diagnosis.... Pyoderma Gangarosum = Ulcerative Colitis (Ulcers) on the skin. Not uncommon with people who have had ulcerative colitis. That's when I found out that it's a systemic disease, and the body loses its resistance to fight off the disease, even though the large intestine is gone. I've had 3 more "bouts" with it.... It can burst, bleed, and then take months to heal. Or it can begin as an irritation (on my belly on my scar) and instead of healing becomes a "hole". That too took months to heal. I had another lesion on my waist from elastic that irritated my skin, and instead of healing a quarter-sized hole just kept getting bigger.
So, it really does pay to check it out, but don't be surprised if most doctors don't realize it. I actually diagnosed it on a friend of mine, who also had an ileostomy due to UC. We're both also diabetic, so that adds to the difficulty in healing. But you can see pictures of it online.
Best of luck to you.