Endo Barostat Study: Determining the role of visceral hypersensitivity or chronic Intestinal inflammation in the generation of gastrointestinal symptoms in endometriosis

The study involves questionnaires, rectal barostat procedures and rectal biopsies. Most participants would routinely receive rectal barostat procedures or rectal biopsies as part of their standard endometriosis care, Initially participants will be required to complete a screening survey and/or have a conversation with the Study coordinator to determine their eligiblity to participate in this study. If the screening survey or study coordinator determines they are eligible to participate in this study, they will have an initial screening appointment (via Zoom) with the study doctor (Dr Rebecca Burgell) who will confirm from a medical perspective they are suitable for the study and to provide the participant sufficient information about the study that they can complete an informed consent form (electronically at home, takes ~10 mins). Consenting participants are then emailed a link to the study questionnaire and posted kits (and instructions) for collecting stool and vaginal samples. The questionnaire + stool and vaginal samples can be collected from home in the days preceding your appointment at the Alfred for the rectal barostat and biopsy procedure (described below). The questionnaire is a one-off cluster questionnaire that takes ~30 minutes to complete and asks questions about gastrointestinal symptoms, endometriosis, quality of life and mental health. The stool and vaginal samples take ~ 10 minutes to collect. On the day of the barostat procedure, participants are required to fast overnight, then in the morning, attend the Gastrointestinal Physiology Laboratory at the Alfred Hospital to complete the rectal barostat procedure. On arrival, participants are asked questions about their gastrointestinal symptoms and bowel habits. If required, they may be given a water enema to clean out the lower part of their bowel. Participants are then asked to lie on their side with their legs bent. After a brief rectal examination, a thin tube with a bag attached is eased gently into place inside the rectum. First, the bag is inflated slowly with a little air and then deflated to ensure that it is lying correctly within the last part of the bowel. The sensation of the bowel are then tested by a series tests where varying amount of air is put into the bag. Participants are given a keypad to register the sensations they feel. Participants are given a button they can press to terminate the procedure immediately. Immediately following the barostat examination, 4 x rectal biopsies are taken. A rectal biopsy is a procedure involving the removal of a small amount (~ 1mm) of tissue from the rectum. To perform this procedure a telescope is passed across the anal canal and special forceps are used to take a tiny piece of the lining of the bowel. The tissue is sent to pathology for testing. Possible complications - possible discomfort during the barostat procedure and rectal biopsies. Small risk of infection and bleeding (which very rarely can be significant) or damage to the rectal mucosa or bowel wall from a rectal biopsy, but this is considered extremely low, less than 1 in 10,000 patients experience this problem. If this did occur, there may be a need for surgery to repair the area. If an abnormality is found on either examination or on biopsy that could impact the participant's health, they will be contacted by the study team and follow up will be arranged through the Department of Gastroenterology at Alfred Health or an alternative clinician (depending on the participant's preference) Total duration of involvement - 1-2 months, depending on when the barostat procedure is scheduled after the initial Zoom screening appt with the study gastroenterologist.