Complications of bariatric surgery: dumping syndrome, reflux and vitamin deficiencies.

Bariatric surgical procedure are increasingly and successfully applied in the treatment of morbid obesity. Nevertheless, these procedures are not devoid of potential long-term complications. Dumping syndrome may occur after procedures involving at least partial gastric resection or bypass, including Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy. Diagnosis is based on clinical alertness and glucose tolerance testing. Treatment may involve dietary measures, acarbose and somatostatin analogues, or surgical reintervention for refractory cases. Gastro-esophageal reflux disease (GERD) can be aggravated by vertical banded gastroplasty and sleeve gastrectomy procedures, but pre-existing GERD may improve after RYGB and with adjustable gastric banding. Nutrient deficiencies constitute the most important long-term complications of bariatric interventions, as they may lead to haematological, metabolic and especially neurological disorders which are not always reversible. Malabsorptive procedures, poor postoperative nutrient intake, recurrent vomiting and poor compliance with vitamin supplement intake and regular follow-up are important risk factors. Preoperative nutritional assessment and rigourous postoperative follow-up plan with administration of multi-vitamin supplements and assessment of serum levels is recommended in all patients.