This topic is about a person who has an ileostomy and is experiencing an unexpected change in the color of their ostomy output. They are on a diet consisting solely of chocolate-flavored Fortisip, a nutritional drink, and have noticed their output has turned dark green, which is unusual for them.

Here are some helpful insights and advice regarding this situation:

1. Dark-green ileostomy output is often due to bile moving quickly through the gut, especially when there is little or no solid food intake. This is usually harmless but should be kept an eye on.

2. While a diet rich in leafy green vegetables can cause green output, this does not apply here since the person is only consuming Fortisip.

3. If the output is bright, fluorescent green, resembling "slime-green," it could be a sign of a Clostridioides difficile (C-Diff) infection, which requires immediate medical attention.

4. Changes in the volume or concentration of bile can also cause the color to shift from yellow to dark green. This change does not necessarily indicate a serious issue.

The person also has an existing ESBL E. coli gut infection and is waiting to start treatment with Carbapenem antibiotics. They have had their gallbladder removed, which means they often see yellow bile output after fasting overnight. However, this new dark green color is different from what they usually experience. They have had similar experiences with green output after extensive bowel surgeries and are concerned this might be related.