Ileal interposition (metabolic surgery for type two diabetes) in Turkey

Ileal interposition is a metabolic operation for type two diabetes in which a segment of the ileum, the last part of the small bowel, is cut out with its blood supply and re-connected higher up, close to the stomach, usually together with a sleeve gastrectomy. The idea is that food reaches the hormone-producing lining of the ileum early in digestion, so that the gut releases more of the hormones that stimulate insulin and reduce appetite, improving blood sugar control in people who are not necessarily severely obese. It is done laparoscopically, takes several hours, involves several bowel joins, and needs days in hospital.

The honest position is that ileal interposition is not a standard operation. The evidence comes from a small number of centres reporting their own series without control groups, the long-term results are thinly documented, and international bariatric and diabetes societies do not recommend it outside research settings. The operations with strong evidence for type two diabetes are gastric bypass and sleeve gastrectomy in people with obesity. A clinic in Turkey offering ileal interposition as the end of diabetes is offering an experimental operation with a promise that no operation can keep.

The published results of ileal interposition come from a handful of surgical teams reporting their own patients, mostly from one country, with remission defined in different ways and follow-up often short. Reports of high remission in early years are real but come from selected patients with short diabetes duration and preserved pancreatic function, the group that also does well after bypass and often with medication alone.

Bypass and sleeve, by contrast, have been compared with intensive medical treatment in randomised trials with years of follow-up, which is why guidelines recommend them for type two diabetes with obesity. No such trial exists for ileal interposition, and the professional societies that set bariatric standards list it as investigational. That is the sentence a patient should hear before the price.

• Leak at a bowel join. Several joins mean several places to leak; a leak is a serious complication needing re-operation or drainage.
• Obstruction and internal hernia. Rearranged bowel can twist or trap; months or years later, and needs a surgeon who understands the anatomy.
• Malabsorption and deficiencies. Iron, vitamin B and fat-soluble vitamins, protein. Lifelong supplements and blood tests.
• Diarrhoea and dumping. Food reaching the lower bowel early causes loose stools, cramps and post-meal low blood sugar in some patients.
• Relapse of diabetes. Remission is not permanent for everyone and depends on the pancreas more than on the operation.
• Difficult revision. Complex to undo or convert, and few surgeons outside the originating centres have done so.
• Sleeve-related risks. Reflux, staple-line leak and the usual risks of a sleeve gastrectomy.

• Ask for the surgeon's own results. Published, with follow-up of years, not a figure on a website.
• Ask why not bypass or sleeve. The evidence-based operations should be offered first, and the reason for choosing something experimental should be specific.
• Ask about C-peptide and duration. If they were not measured, the prediction of remission is a guess.
• Check the hospital. Accredited, with intensive care and a surgical team able to manage a leak at night.
• Arrange home follow-up before you go. A diabetes physician willing to manage falling medication needs and a doctor who will order the vitamin bloods.
• Plan the stay. Several days in hospital and enough time before flying for early complications to declare themselves.

• International Federation for the Surgery of Obesity and Metabolic Disorders, position statements on metabolic surgery for type two diabetes and on investigational procedures.
• American Society for Metabolic and Bariatric Surgery, guidance on metabolic surgery and on emerging procedures.
• American Diabetes Association, standards of care in diabetes: obesity and weight management, metabolic surgery.
• Cochrane Library, surgery for weight loss in adults, systematic review.
• Republic of Türkiye Ministry of Health, register of healthcare providers authorised for international health tourism.