Case Presentation: Thiamine deficiency is a known complication of bariatric surgery presenting commonly as Wernicke encephalopathy or dry beriberi. Pure sensory ascending neuropathy as a presenting complaint, however, is rare, which we describe here in the acute setting after intragastric balloon (IGB) placement. A 48 year old obese but otherwise healthy female underwent an uncomplicated placement of an IGB for weight loss therapy. Post-operatively, patient experienced persistent gastric discomfort and nausea, prompting premature removal of the IGB 3 months post-placement. Her BMI decreased from 37.4 pre-procedure to 30.5 at the time of IGB removal. Post-removal, patient endorsed immediate relief of her nausea and abdominal discomfort. However, at 8 weeks post-IGB placement, patient initially noticed symmetric numbness starting in her ankles and ascending rapidly. Patient was hospitalized for evaluation. Exam was significant for symmetrically decreased light touch, pinprick, and temperature in the distribution of the medial malleoli, inner thighs, and abdomen/thorax. Weakness, areflexia, or respiratory compromise was not noted. MRI imaging of the brain and spine was normal. Expanded nutritional labs revealed low serum thiamine at 57 nmol/L (70-80 nmol/L). Otherwise, labs were normal. Patient was prescribed oral thiamine supplementation and reported improvement in symptoms within weeks, with almost complete resolution at one year follow up.

Discussion: Although bariatric surgery has multiple benefits via weight reduction, many possible complications exist as a result, including metabolic derangements with which patients are admitted to the hospital. In addition to pre-existing micronutrient deficiencies in obese patients, poor dietary compliance and malabsorption post-operatively can result in nutritional deficiencies, exacerbated by persistent vomiting as in this patient. In particular, thiamine deficiency can occur early after bariatric procedures due to low storage reservoirs in the body, presenting typically as Wernicke encephalopathy or dry beriberi. Isolated ascending sensory neuropathy is a rare presentation, which was seen in our patient.

Conclusions: As bariatric procedures become more popular in clinical practice, it is important for hospitalists to be aware of the potential complications, including nutritional deficiencies and their various clinical presentations. A known late complication is thiamine deficiency, but it can also occur early post-procedure as described in this case with a unique presentation. After ruling out common causes of neuropathy, a diagnosis of ascending sensory neuropathy secondary to thiamine deficiency can be made in the setting of low serum thiamine. Patients with mild symptoms can be treated with oral thiamine supplementation instead of high doses of IV thiamine typically given for serious manifestations of Wernicke’s encephalopathy or dry beriberi. Thus, it is important for hospitalists to recognize this easily treatable, but unique, condition.