Adolescent Bariatric Surgery and Thiamine Deficiency: What Do We Know So Far?
We read with great interest the recent article by Armstrong-Javors et al1 published in the December 2016 issue of Pediatrics that describes a case of Wernicke encephalopathy (WE) 2 months after Roux-en-Y gastric bypass (RYGB). The authors report a rare case of WE resulting from thiamine deficiency in a 15-year-old white girl who underwent RYGB. According to the article, WE was suspected because of the progressive neurologic symptoms (nystagmus, irritability, ataxia) and frequent vomiting. The aforementioned case is important because it reports not only a rare but also an acute complication after bariatric surgery with notably increased mortality and morbidity. Furthermore, this review revealed that the overwhelming majority of the cases of WE after bariatric surgery occurred during recent years. There are 3 solid reasons for the aforementioned increase.
Firstly, adolescent obesity has dramatically increased worldwide in recent decades, and the prevention strategies for obesity are failing. Because pharmacological and behavioral treatment options have had mainly poor results in the treatment of obesity, bariatric surgery has emerged as an alternative treatment option. Bariatric surgery in adult populations has proved effective with superior outcomes in terms of weight loss and remission of obesity-associated comorbidities; however, long-term results and complications after bariatric surgery in obese adolescents are not yet available. According to Armstrong-Javors et al,1 there are only 9 definitive adolescent cases of WE after bariatric surgery reported in the literature. Our review of the literature revealed that there is also a dramatic increase of the published cases of WE after bariatric procedures in adult populations during recent years.2,3 Because bariatric surgery in pediatric patients has been used increasingly within the last few years, there is a consequential rise in complications, mainly severe micronutrient deficiency, protein-calorie malnutrition, gastrointestinal obstruction, and pulmonary embolism.
Secondly, RYGB is the most commonly performed procedure in adolescents with obesity in the United States, and the risk of severe micronutrient deficiencies after malabsorptive procedures such as RYGB is significantly higher than restrictive bariatric procedures such as sleeve gastrectomy and laparoscopic adjustable gastric band. The RYGB reduces the absorption of thiamine mainly because it bypasses the duodenum and more than 30 cm of jejunum beyond the ligament of Treitz. Moreover, small intestinal bacterial overgrowth because of altered gut ecology is associated with the development of thiamine deficiency and WE.4 Last but not least, the majority of patients undergoing bariatric procedures do not receive adequate and appropriate nutrition supplements, including supplemental vitamin B1, not only after but also before the operation, and for this reason, these patients are more likely to develop WE.5
Overall, bariatric surgery in adolescents should be offered only within authorized adolescent obesity prevention programs provided by interdisciplinary adolescent obesity teams, and only within specialist centers, to minimize detrimental complications and improve outcomes. Furthermore, patients and family should be informed and educated about the risks and benefits, expected complications, potential eating behavior changes, careful nutritional follow-up, and lifelong requirement for multivitamin supplementation.
CONFLICT OF INTEREST: The authors have indicated they have no potential conflicts of interest to disclose.
- Copyright © 2017 by the American Academy of Pediatrics