Thrombotic thrombocytopenic purpura following one anastomosis gastric bypass surgery: a rare case report.

Introduction and importance: One-anastomosis gastric bypass (OAGB) is a common bariatric intervention with recognized safety but rare hematologic complications. Thrombotic thrombocytopenic purpura (TTP) has not been reported following OAGB. Case presentation: A 20-year-old female with morbid obesity (BMI 49.5 kg/m Clinical discussion: TTP is recognized as an emergency medical condition that can mimic surgical postoperative complications. Unlike previous reports of TTP following sleeve gastrectomy or cardiac surgery, this case occurred after OAGB, which is a procedure not previously associated with this complication. In this case, early gastrointestinal symptoms initially suggested surgical causes, but the acute decrease in platelet count and microangiopathic hemolysis were two diagnostic indicators. Plasma exchange therapy remains the cornerstone in treatment and significantly increases survival rates when started early. Conclusions: Although clinically rare, TTP should be considered in post-OAGB patients presenting with unexplained cytopenia and neurological symptoms. Early diagnosis and prompt initiation of plasma exchange are critical for lifesaving outcomes.