Thiamine deficiency-related neuropathy: A reversible entity from an endemic area

Abstract

Background and purpose: Despite thiamine deficiency being a lesser-known entity in modern times, beriberi in various forms, including thiamine deficiency-related neuropathy, remains endemic in Kashmir due to the consumption of polished rice as a staple food. This observational study investigates cases of peripheral neuropathy of unknown etiology and their potential responsiveness to thiamine administration. Methods: This prospective study enrolled adult patients presenting to the emergency department with weakness consistent with thiamine deficiency-related neuropathy and conducted a therapeutic challenge with thiamine on 41 patients. Response to thiamine therapy was monitored based on subjective and objective improvements in weakness and power. Patients were divided into thiamine responders (n = 25) and nonresponders (n = 16) based on their response to thiamine therapy and nerve conduction studies. Results: Most of the baseline characteristics were similar between responders and nonresponders, except the responders exhibited lower thiamine levels and higher partial pressure of oxygen and lactate levels compared to nonresponders. All patients had a history of consuming polished rice and traditional salt tea. Although weakness in the lower limbs was present in both groups, nonresponders were more likely to exhibit weakness in all four limbs. Clinical improvement was observed within 24 h, but proximal muscle weakness persisted for an extended period of time. Conclusions: Thiamine deficiency-related neuropathy presents with predominant lower limb weakness, exacerbated by vomiting, poor food intake, psychiatric illness, and pregnancy. Thiamine challenge should be followed by observation of clinical and biochemical response.