Nystagmus Response to Thiamine Replacement, a Predictor of Wernicke-Korsakoff (WE) Syndrome Outcome. A 21-patient Cohort Study (S12.002)

Abstract

<h3>Objective:</h3> To identify an easily recognizable clinical marker of thiamine deficiency to procure timely diagnosis <h3>Background:</h3> Wernicke’s Encephalopathy (WE) treatment outcome depends on genetic factors, duration of insufficient thiamine, metabolic demand and comorbidities. Nystagmus is by far the most frequent ocular motor finding abnormality in thiamine deficiency. Its response to treatment predicts outcome. <h3>Design/Methods:</h3> This is a retrospective series of 21-patient cohort, 16 acute patients, studied as on-going acute vestibular syndrome/ataxia cohort (two telemedicine), and 5 outpatients. All underwent neurological and neurophthalmologic examination and nystagmus recordings, they had at least one abnormal ancillary test; low serum pre-treatment thiamine, or abnormal head MRI. <h3>Results:</h3> Nine patients had horizontal (h) nystagmus (two types: vestibular and gaze holding nystagmus); thiamine replacement led to rapid nystagmus resolution, and prevented encephalopathy in all (including one, who had also upbeat nystagmus/truncal ataxia (UBN/TA), one patient has chronic UBN/TA for one year with improving WE at a slower pace. Six patients had conversion from UBN to permanent downbeat nystagmus/truncal ataxia (DBN/TA), and slower WE recovery; one patient had improved UBN/TA. Three outpatients with permanent DBN/TA had a previous history and labs compatible with thiamine deficiency. One patient did not have nystagmus. None of the study-cohort patients developed Korsakoff’s syndrome (KS). <h3>Conclusions:</h3> In patients at WE risk, h-nystagmus was the earliest sign of thiamine deficiency in this cohort, had the fastest response to thiamine, which also prevented WE. Vertical nystagmus had longer WE recovery, and six patients had enduring DBN/TA. Interestingly, none of the 21 patients developed KS. This series highlight the key role of nystagmus analysis in thiamine deficiency. Adding nystagmus to Caine’s diagnostic criteria may enhance the early features of thiamine deficiency. <b>Disclosure:</b> Dr. Kattah has received personal compensation in the range of $500-$4,999 for serving as an Expert Witness for Bonezzi, Switzer , Poilitto and Hupp Legal Firm.