Severe lumbosacral polyradiculopathy secondary to micronutrient deficiencies in a patient on semaglutide therapy following bariatric surgery.

Summary: Bariatric surgery and glucagon-like peptide-1 receptor agonist medications (GLP-1RAs) are common and effective methods for treating obesity. Since bariatric surgery is associated with an increased risk of malnutrition, there are extensive post-operative dietary recommendations and nutritional monitoring guidelines. There is, however, less evidence regarding the risk of malnutrition with GLP-1RAs and little research on the use of GLP-1RAs in patients post-bariatric surgery. We present a clinical case in which a 39-year-old male on semaglutide therapy presented with severe weakness and inability to ambulate. His symptoms had developed over the prior 3 months following transoral outlet reduction surgery and worsened with an increase of his semaglutide dose to 1.7 mg/week. Physical examination demonstrated severe distal-predominant bilateral lower extremity weakness, loss of lower extremity reflexes, and impaired sensation distal to the T4 dermatome. Laboratory serum testing revealed thiamine and vitamin E deficiencies. Lumbar magnetic resonance imaging demonstrated mild homogeneous enhancement of the cauda equina nerve roots, neural foraminal narrowing, and disc protrusions without significant spinal canal stenosis. Given the absence of structural abnormalities, he was diagnosed with lumbosacral polyradiculopathy due to micronutrient deficiencies. Treatment included discontinuation of semaglutide and initiation of thiamine and vitamin E supplementation. He was admitted for inpatient rehabilitation therapy and demonstrated improvement of motor and sensory symptoms over the next month. With the increasing use of GLP-1RAs, it is crucial for clinicians, dietitians, and pharmacists to understand the risk and pathophysiologic processes of these medications when used in combination with other weight-loss therapies such as bariatric surgery.

Learning points: While there are robust pre- and post-operative micronutrient screening guidelines for patients undergoing bariatric surgery, nutritional monitoring guidelines are limited for patients on GLP-1 receptor agonist therapy or for patients with a history of bariatric surgery who are on GLP-1 receptor agonist therapy. The use of multiple weight-loss therapies that suppress appetite and nutrient intake may increase the risk of micronutrient deficiencies. Micronutrient deficiencies can have severe neurological manifestations, which may be correctable with nutritional supplementation. Avoid initiating GLP-1 receptor agonist therapy in close proximity to bariatric surgery. Further research is needed focusing on patients using multiple weight-loss therapies. This may contribute to the development of specific nutritional and micronutrient monitoring guidelines for this population. Endocrinologists, bariatric surgeons, and primary care providers must work together to care for patients undergoing weight-loss interventions.