Anatomical Reconstruction After Metabolic Bariatric Surgery (MBS): Indications and Biochemical Responses in Post-Bariatric Hyperinsulinemic Hypoglycemia Patients—A Single-Center Case Series

Introduction: Anatomical gastrointestinal reconstruction following metabolic bariatric surgery (MBS) is a revisional procedure used for refractory complications, including malnutrition, intractable reflux, recurrent marginal ulcer disease, and post-bariatric hyperinsulinemic hypoglycemia (PBHH). Objective: This study aims to describe the indications, perioperative outcomes, and short-term results of laparoscopic anatomical reconstruction in a single-center series, focusing on patients with PBHH. Methods: We retrospectively reviewed 11 consecutive patients who underwent reconstruction following MBS at a single tertiary center. Perioperative outcomes, weight changes, and biochemical responses to standardized dual-modality (oral and intravenous) glucose suppression testing were analyzed. Results: Between 2018 and 2025, 11 patients completed laparoscopic anatomical reconstruction. The anatomy immediately preceding reconstruction was OAGB in nine patients (81.8%) and RYGB in two (18.2%). The indications overlapped; the most common were severe malnutrition (n = 9), marginal ulcer disease (n = 6), and PBHH (n = 4; three biochemically confirmed, one clinically diagnosed). Ten of eleven procedures (90.9%) were completed laparoscopically, with no 30-day Clavien–Dindo grade III–IV complications. Among the four PBHH patients, symptomatic resolution was achieved in all four, with residual asymptomatic biochemical hypoglycemia in one. Weight gain occurred in 10 of the 11 patients (mean 8.1 ± 4.9 kg) at a median follow-up of 7 months (IQR 3–12). Conclusions: In this preliminary series, laparoscopic anatomical reconstruction was feasible, though the small sample precludes conclusions regarding safety. Incretin hormones were not measured; the mechanistic contribution of restored foregut anatomy is inferred from prior literature rather than demonstrated here. Standardized dual-modality glucose suppression testing was central to patient selection and to documenting the biochemical response.