Versatility of Duodenal Transit Bipartition: Duodenoileal Anastomosis at the Third Portion of the Duodenum

Context: Duodenal transit bipartition is a metabolic and bariatric surgical concept proposed by De Melo, representing an adaptation of the classic concept of intestinal transit bipartition proposed by Santoro [1]. The architecture of the procedure is versatile and, owing to the postpyloric positioning of the duodenoileal anastomosis, allows its performance at different anatomical portions of the duodenum. Recently, we published an article demonstrating the versatility of this technique. The classic procedure is performed at the first portion of the duodenum. At the first postoperative outpatient evaluation, 30 days after the procedure, the patient presented a weight loss of approximately 11 kg, corresponding to approximately 10% of her initial body weight, with excellent clinical tolerance. Case Presentation: Female patient, 30 years old, with a 15-year history of progressive class III obesity, presenting an initial body weight of 112.2 kg, height of 1.62 m, and baseline body mass index (BMI) of 42.8 kg/m². The patient had a documented history of repeated failures of clinical and pharmacological strategies for weight management. Previous interventions included lifestyle modifications, hypocaloric nutritional regimens, and the use of semaglutide, a glucagon-like peptide-1 (GLP-1) receptor agonist, which resulted in an initial weight loss of 12 kg but had to be discontinued due to fatigue symptoms. Subsequently, a therapeutic attempt with tirzepatide was carried out for two months, without measurable weight reduction. Her surgical history included a previous cholecystectomy. The patient had no diagnosis of type 2 diabetes mellitus, systemic arterial hypertension, or active symptoms of gastroesophageal reflux disease, and denied tobacco and alcohol use. Preoperative evaluation by upper digestive endoscopy revealed moderate antral gastritis, with a negative rapid urease test. Abdominal ultrasonography identified grade 2 hepatic steatosis. Laparoscopic sleeve gastrectomy combined with duodenal transit bipartition was indicated and performed. During the surgical procedure, an anatomically unfavorable duodenal configuration was identified, characterized by a short and plunging first portion of the duodenum, precluding its safe mobilization for the performance of the duodenoileal anastomosis. Consequently, the surgical strategy was adjusted to establish the duodenoileal anastomosis at the horizontal third portion of the duodenum, via an inframesocolic approach. After careful retroperitoneal dissection, a 4.5 cm