Hematological Disorders Following Bariatric Surgery

Bariatric surgery is a highly effective therapy for morbidly obese patients. Roux-en-Y gastric bypass (RYGB) is usually the most common bariatric surgery procedure performed worldwide. It not only produces significant and durable weight loss, but also results in improvement of obesity-related comorbidities. However, the major problems related to this surgery are nutritional deficiencies and chronic hematological complications, like anemias pertaining to anatomical and associated physiological alteration of the gastrointestinal tract. Anemia after RYGB has been associated with insufficient intake and malabsorption of micronutrients such as iron, vitamin B12, folate, and copper concomitantly with obesity-mediated chronic inflammatory anemia. The crosstalk between chronic inflammation, immune dysregulation, and long-term sequelae of nutritional deficiency may lead to a complex suppression of normal hematopoiesis, manifested as persistent anemia only partially responsive (or nonresponsive) to nutritional supplementation. Clinical follow-up and early diagnosis are essential to allow appropriate intervention before potentially irreversible clinical manifestations occur.